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Hi All,
My 940 is from 1997, B200FT, 2.0L SW with 277000 Km.
About a month ago, I started to hear a ticking sound while accelerating.
Due to the pandemic, I drove the car only 250Km during the winter 2020, I was just driving it 15 min. every week.
However, starting from this summer, I could drive it more frequently, and now I drive it about 300Km/week.
The ticking increases as I accelerate, but it is always there, also on the highway, although not as evident due to the background noise of the car.
For this car, I have always used Castrol Edge Synthetic 5w-30.
Although I only drove 250km with the oil during the pandemic, I have changed it with the hope to get the ticking away, but no go.
As an additional info, since a number of years, when accelerating, the car slightly bogs down, but this never really concerned me because it is mainly at full acceleration, for the rest it drives smoothly, even now that it is ticking.
Distributor and spark cables are brand new.
I never cleaned the injectors, so I was thinking if that could be a possible cause.
As always, any advice is very welcome.
Thank you!
Alex
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Hi guys,
Finally, I got the new manifold, so I have re-assembled everything, including the turbocharger, the down pipe, all the hoses and filled in the cooling system.
I have turned the engine on, the car started, I left it idle (it is still on my cribs), but for whatever reason the turbo smokes, in the area between the downpipe and the clamp that retains the turbo to the wastegate housing.
I have no idea why it is smoking, I left the engine on for 3-4 minutes, but the smoke was increasing, so I turned the engine off.
Initially I thought it was because I cleaned everything, including the turbo (outside only), so I used CRC and there might be some oil/grease on the downpipe.
I have also used Permatex on the threads, but it seems a lot of smoke, and that should disappear after a few minutes, right?.
I checked under the car, there are no leaks.
I also changed the gasket between the oil filter and the adapter.
Since I just removed the filter, I expected the oil level to decrease at least 0.6L from the dipstick, but it seems to be on the same level so far.
There are no warning lights anywhere in the dashboard.
I do not think to have forgotten anything, in terms of hoses.
Any help is appreciated.
Alex
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Dear Metallo,
As you know I don't have turbo. In NA setup the exhaust side of the engine is normally clean of any oil. Even if it smokes usually it came from oil leaking from valve cover or any recent exhaust repair. Some new exhaust gaskets do smoke during first start.
So I'd imagine in your turbo setup the additional sources of oil leaking could be from oil feed pipes for the turbo and oil spray from leaked oil cooler beneath the turbo. New exhaust manifold could sometimes be coated with protective oil at the factory.
If the smoke is not much like those happen during fogging for dengue mosquito (in my tropical country Malaysia) then I think not much to worry about there.
Amarin
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Hi Amarin,
I have recorded a video of the turbo charger smoking, while the engine was idle.
https://www.mediafire.com/file/w5mz5i3wr1hc51g/VID_20220207_201459.mp4/file
It stopped after about 30 mins.
I believe the cooling fluid was not fully circulating in the system, because when I started to push the gas pedal, I heard for a few seconds the liquid going through all the circuit, as if there was some trapped air.
Then I started to drive the car, and it was driving very smooth.
It does no longer smoke and everything seems to run very well.
I just want to say thanks to all the Bricks community for the great help and support you offered me during this project.
It was a long way, given that I had to purchase the exhaust manifold twice, but eventually I got the result I was hoping for.
In a couple of weeks, I will have a long drive, about 4000 Kms, which is the real test :)
Thanks again, and will stay in touch on my next project!
Alex
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Dear Metallo,
Thanks for the update! Yes I'd say thats still normal amount of smoke after exhaust parts change. I've seen the video - smooth running engine! Glad this one sorted out.
Amarin.
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Hi guys,
Hopefully, I will receive soon my new exhaust manifold.
I cannot find the Nm torque specs for:
- 3 nuts on the back of the turbo to the header downpipe
- 4 nuts on the turbo to exhaust manifold
- 8 nuts + 1 under that connect the exhaust manifold to the block.
Does anybody know/
Thank you
Alex
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Dear Metallo,
Hope you're well and stay so. Further to my reply, the "copper paste" seems to be the sealant, to be used in place of a gasket. In your photos of the failed manifold, the gaps between the manifold and the turbo - and between the turbo and the down-pipe - likely resulted from deterioration of the factory-installed "copper paste".
I would be sure to use the Volvo-specified "copper paste", unless someone well-experienced in this sort of "plumbing" can recommend an alternative. I also hope such a person will describe in detail how to install the "copper paste", i.e., how much to use and how it is to be "cured".
Hope this helps.
Yours faithfully,
Spook
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Looks like there are marked difference on the port holes of the new vs old manifolds. However, do a trial fitment first using the 4 exhaust gaskets. The exhaust gaskets are metal-lined and you can't alter it. Hopefully those 4 are still within acceptable tolerance. I can't comment on the turbo hole on the manifold as I never had any turbo.
Amarin
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Man,
I do not need to try the four holes to the head for matching, my major concern was the slot of the Turbo hole, in fact, it does not fit as the original, on one side there is at least 1 mm of air.
I am so disappointed, I had to wait two weeks and I received this peace of junk made in Poland, unbelievable!
Tomorrow morning I will send some pictures to Volvo in Toronto and will ask for a refund.
The question is: what to do next?
I could order a new one in Europe, but how can I be sure that I will not receive another piece of junk, after 5 weeks?
Tomorrow I am going to see a machine shop who builds engines, performance hot rods and muscle cars, they may be able to tell me if welding the old manifold is a good option or not.
Are stainless steel exhaust manifolds better than cast ones?
Thank you,
Alex
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Hi Metallo,
"I do not need to try the four holes to the head for matching"
Yes you do. Its the sum of these small gases thats going to arrive at the big hole later. Your system is low pressure turbo where careful matching is not that crucial. Your turbo is to slightly increase engine power at overtaking and high speed. Unlike full turbo.
"The question is: what to do next?"
If it was me, I'd just bolt on the new manifold. The cast iron manifold is considered "Stage 0" in turbo scheme of upgrade or "baseline" if you prefer. I thought you wanted to get rid of that ticking noise in the first place.
"they may be able to tell me if welding the old manifold is a good option or not."
Welding is always an option in case of any cracked cast manifold. Its the longevity issue thats going catch you later on.
"Are stainless steel exhaust manifolds better than cast ones?"
Of course steel is better. They're custom made with better gas flow, better heat transfer at the expense of cost, increased noise and space to install. Cast iron is cheaper to make, more practical for normal user and compact to install. Unless you're going to upgrade the turbo's performance in stages later, cast iron is good enough.
Amarin.
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Hi Amarin,
Thank you for your comments.
I meant to be sarcastic when I wrote that "I do not need to try the four holes to the head for matching", in fact, the slot of the Turbo hole does not fit as the original, on one side there is at least 1 mm of air. The issue is where the indents are, in that point the groove is not perfect and it just does not slot in completely. This manifold cannot be used.
The machine shop I mentioned in my previous post, will re-open tomorrow, let's see what they say with regards to the old manifold.
Thanks,
Alex
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For the copper paste, you may wish to refer to this old brickboard thread
RWD: Hi Temp exhaust sealant (900)
I initially assumed it was just the Volvo priced version of a standard high temp, copper based anti-seize compound such as used on brake calipers, but it is obviously higher temp than most so it can also be used on exhaust manifold stud and turbo bolt threads and as well is used surface to surface. When used surface to surface it enables slight movement between extremly hot surfaces with quite different coefficients of expansion and also protects where corrosion may be present or likely to form. I've never seen it called for on the RWD red block engines, only the FWD/AWD turbo'd white blocks, but I can't imagine it would hurt if you don't mind spending that gross amount of money and have a specific problem you're trying to deal with.
I see there's a high temp white ceramic grease rated for 1,400 degC (2,500 degF) used for O2 sensors and brake calipers that cross references to the Volvo p/n 1161408 for considerably less money made by Febi Bilstein (p/n 26711 for a small tube, p/n 26712 for a small tub). It's apparently OE for Mercedes, VW, etc. brakes, so may well be available from other import parts counters under various part numbers. The Bilstein website says it can be used on 'cylinders', meaning spark plugs and anything on the block I presume. It is sold on Amazon/eBay and other places, but I don't see it listed in stock in North America at the moment. From what I can tell, the hot compressed gas side of most auto turbos runs closer to 1,000 degC, so it should be quite okay to use. Product sheets for most of the high temp copper pastes I see out there are rated more like 1,200 degC, which should still be adequate for most exhaust applications, with turbos at the high end of temperature.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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Dear Metallo,
Hope you're well. Yes! According to the Volvo Pocket data booklet - Cars (700, 900, S/V90, 850, S/V/C70) 1991-1998, p. 38, the torque values are:
Turbocharger-to-Manifold ............... 30Nm (22 pound/feet)
Turbocharger-to-Exhaust Pipe ....... 30Nm (22 pound/feet).
There are two notes:
(a) Use special tools 999 5411 (90-angle to torque wrench)
(b) Use copper paste (P/N 1161408).
The copper paste - known in Volvoese as "bolted joint paste" - should be available from a U.S.-based Volvo dealer for about $50.00.
For the exhaust manifold to head, the torque spec is 25Nm = 18.4 pound/feet ( ibid., p.48).
Hope this helps.
Happy Holidays!
Yours faithfully,
Spook
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Hi Spook,
Thank you very much for the info you have provided.
I cannot find the Pocket data booklet - Cars (700, 900, S/V90, 850, S/V/C70) 1991-1998.
Any chance you can point me to a link I can download it?
I searched here https://www.volvoclub.org.uk/volvo_workshop-datasheets.shtml but as you can see, that specific book is not there :(
Thank you!
Alex
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I.used a dremel tool with a thicker cutting disc and shaved each exhaust nut on one flat of each nut until I could see.the stud thread. It doesn't hurt the stud to have the stud threads shaved a little while shaving. There will still be plenty of threads. I did this after breaking a few studs.
Horizontally shaving each exhaust nut is now my method of getting those rusted exhaust nuts off. No more busting studs.♻⚠♻⚠♻⚠♻⚠
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Hi guys,
Eventually, I know now what causes the tic tic:
Now, what's the best way to go?
I know welding is cheaper but, you need to find someone who knows what he's doing.
Otherwise, a new manifold? I see Tasca still sell it for $481.55
Alex
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Hi Alex,
You said a mouth full! “ I know welding is cheaper but, you need to find someone who knows what he's doing.”
There are a couple ways to go either with acetylene gas welding or electric arc welding with a cast iron welding rod. They have been out for many many years!
Check into local welding store knowledge base for hobbyists or a professional.
Gas welding brazing with a brass filler rod would expand the metal and fill the crack.
The crack came from stresses in the casting and repetitive contractions and so forth over the years.
I believe brazing might work best if the crack is properly prepared with a slight “V” gouged and some face surfacing to spread the seal some.
The same would needed to be done with a cast iron rod and from both sides as well.
The cast rod would show less but high temperature paint makes all of that mute.
The electric arc method there would induced some stress into the joint and I would advise having the manifold “Shot Peened” afterwards but you crack is small and you might pass on that!
This treatment vibrates the cast surface around and below the weld metal to relieve cooling stresses.
Someone with a sand blasting cabinet can knock it out in short order. Otherwise a lot of tapping with a ball peen hammer might be enough. Again it’s a small project.
The brazing heat sort automatically relieves its own stresses as it is applied.
In either method of using preheat, I suggest covering up the manifold afterwards to slow down the cooling process to something like bolted an engine head would do naturally.
In other metal treatments, a big bin of crushed animal bones, ash and fine rock is used. Even packed in dry dirt when desperate.
So, if someone who is into that kind of work will have access to these tools and methods is the go too guy or gal!
Their are lots of hobbyist or want to be blacksmiths around if you get into those circles around community colleges.
$500 for one four banger exhaust manifold is ridiculous as we know if the manufacturers paid those kinda prices we couldn’t afford to buy a production car and why we don’t drive exotic automobiles!
Too network, is to find ones options!
Trust me, manufacturers do!
Phil
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Dear Metallo,
Hope you're well and stay so. Go to a custom exhaust shop - likely to have someone, well-experienced in welding manifolds - and find out if the cracks can be welded. Severe corrosion may leave so little metal beside a crack, that there's no way "to overlay" the crack with new metal, and so to seal the leak.
If the manifold is too far gone to save, you might find a good used unit. As your need is immediate, buy only if you can get a 30-day guarantee. Having the unit inspected. If it is sound, all's well. If not, return it and get a new manifold from Tasca.
Hope this helps.
Stay well and Happy Holidays!!!
Yours faithfully,
Spook
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Casted metal thats welded usually cracks again next to the weld. Order a good use manifold. So much expansion and contraction with exhaust temps.
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Dear Metallo,
Hope you're well and stay so. You can ease the task of replacing exhaust manifold gaskets by: (a) using a hand-held rotary tool (e.g., Dremel) and a wire brush to remove rust from the ends of the studs; (b) saturating the clean stud ends with PB Blaster or other penetrating oil, for several days; (c) before trying to remove the nuts, turn each nut as if you wanted to tighten it.
Doing (a) reduces the amount of energy needed to remove the nuts. Doing (b) helps to break the corrosion bond between the nut and stud, as the penetrating oil works its way through micro-channels in the corrosion. Doing (c) - even if you move the nut by .001" - also helps to break the corrosion bond.
When you re-assemble, use the rotary tool to clean all corrosion from the stud. Then apply a nickel-based anti-seize compound, which should have a temperature rating of 2,500°F. Copper-based anti-seize compound have a lower temperature rating, so may make it harder to remove the nuts.
Finally, you can get a little bit more work room, if you can remove the exhaust pipe brace, that connects the pipe to the transmission housing. Removing the brace allows the exhaust down-pipe and manifold to be pulled a little further away from the head.
That eases: (a) cleaning the surfaces of the manifold and head, which cleaning helps to ensure a better seal between the gaskets and the mating surfaces and (b) inserting the replacement gaskets. A fine sandpaper will remove: (a) any bits of gasket material and (b) any corrosion.
Hope this helps.
Yours faithfully,
Spook
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Thank you all for your recommendations.
I will see what I can do, as the time to do the job is the real pain for me.
I am also scared that I end up to do the job and discover that the gaskets are not the issue. :(
Let me think how to best handle this.
Thank you guys!
Alex
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Most likely a bad gasket. Manifolds don’t crack very often. Suggest doing the smoke test as Amarin mentioned. Also, this method goes back to my crazy younger days… So be very careful if you decide to try this. When the engine is stone cold you can use your fingers to help locate the leak. Don’t touch the manifold! Just feel the air for a leak. It will probably take multiple tries to test all the gaskets using this method as the exhaust manifold warms quickly. Again, only do this when the engine is stone cold!!
--
Will I buy another Volvo??? We'll see....
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Dear jwalker,
Hope you're well and stay so. To leverage your idea, before start-up, wrap clean, damp rags snugly around each exhaust manifold arm, where it meets the head.
Damp rags won't burn. Damp rags are more easily compressed and so more likely to form a tight seal.
Start the engine and listen for a moment. If there's no noise, that suggests one of the gaskets has failed.
Then, remove each of the rags and listen for a moment. When the noise is heard, that points to the failed gasket. At once turn-off the engine.
It should be possible to finish this test before the manifold is so hot, that touching it will cause a burn. When doing this test, there's no reason not to wear gloves: sound - not touch - conveys the test results.
Hope this helps.
Yours faithfully,
Spook
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Hi Spook,
Your idea is great, but unfortunately there is no noise when the engine is idle.
Even the Volvo mechanic could not hear it.
However, it is loud and clear when you drive the car.
What are the main gaskets to check?
I guess the 4 of the manifold and the one that connects the downpipe?
Alex
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Hi Alex,
Ok no exhaust leak during idle using the prescribed test.
Just a thought. I think most of us 940 owners are using auto transmission cars which changes to appropriate gear during acceleration. I've owned manual gear non-Volvo cars in the past and noticed some peculiar symptoms during acceleration. If I accelerate without changing gear (lets say in 4th or 5th gear) the engine did produce some metallic ticking sounds. No exhaust leak of the cars. Just inappropriate gear.
My question is did you accelerate without changing to appropriate gear first? If so, try accelerating using 2nd or 3rd gear to see if the ticking sound still there. Just a thought here. And I still think you're a wonderful driver : -)
Again, a smoke test would be more helpful b'cause you could see the leak (if any).
Amarin.
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Dear Metallo,
Hope you're well and stay so. If the leak-noise increases with power used (engine speed), have someone press the accelerator to bring the revs up to 2,800-3,000/minute. That is the equivalent of driving at 65-70 miles/hour.
Then remove the damp rags, one manifold arm at a time.
It is possible that the leak is in at the "Y" in the down-pipe. The same test as above described will help. Tightly wrap the "Y" with damp cloths. Bring the engine up to speed and then remove the cloths. If the noise then is audible, there's a leak. A down-pipe leak may be repaired by a skilled welder.
Hope this helps.
Yours faithfully,
Spook
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Simply revving the engine in park or neutral with no load on it won’t always make an exhaust leak obvious. Try putting the car in gear, hold the brake firmly, and then give it the throttle.
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Great idea, Spook!
--
Will I buy another Volvo??? We'll see....
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As long as we're suggesting easy and safe ways to locate a blown gasket exhaust leak -- I'll suggest a length of vacuum hose (something like 1/4 inch or so) -- one end gets held into your ear - the other end gets probed around the possible areas. You'll hear it for sure. - Dave
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Hi Dave,
My 940 has been ticking for a while now. Car runs well but the sound is obvious, especially when the car is still cold. I will try your technique to see if I can run down where it is coming from. Thanks for the tip.
Bob
p.s. all the other issues you shepherded me through have been doing fine. Horn works, high brake light works, etc. Thanks again for your valuable input.
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The B230’s with with the shorter (reduced friction) piston skirts are known to develop piston slap as they age. Loudest when cold and/or accelerating. They often quiet down as they warm up.
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Hi Alex,
+1 on exhaust components, namely gaskets leak. Check them. Doing smoke test is easier to detect. I use Marvel Mystery Oil into intake manifold. Lots of white smoke.
Amarin.
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Hi All,
Thank you for offering your advice.
Today I went to see the Volvo dealer, one the mechanics came outside to take a quick look, I asked him to drive the car in the parking lot as the sound is evident only when you drive under load.
His opinion is that the ticking is coming from the exhaust manifold or downpipe, but he said it is hard to know for sure without a proper inspection.
The mechanic was younger than my car!
I have never changes those gaskets in 25 years, so I guess it could be possible.
I found this post in the forum: https://www.brickboard.com/RWD/index.htm?id=1668229&show_all=1
It seems a difficult job to do, considering the risk of snapping the various studs.
I have done many jobs on my car, but this one seems to be tough.
Also, the only time I would have to do it, is during the Christmas festivities, but it is bloody cold in the garage.
I can heat the air, but when it comes to laying on a creeper is not fun.
Assuming the mechanic is right, what happens if I postpone this job to the spring?
I drive the car regularly, including highway, about 300Km/week.
Alex
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I wouldn't postpone the job. Too easy to have it let go and leave you stranded at an inopportune time, possibly also damaging the manifold.
I had a ticky/puffy noise start up that I soon visually determined was an exhaust gasket leak hiding below #4 runner. I’d been dragging my feet for a couple of weeks about taking it in to my indie as I was busy. Typical gotcha, waited til I was en route coming home on the highway after a relaxing weekend trip, already planning to make an appointment in the next couple of days to have it done, when it let go. People must have thought I was jake braking as I pulled off to the side to limp off at the exit that was luckily right there. Fortunately no additional damage done other than a tow bill I wasn't planning on. Lesson learned, yet again.
On some engines there’s an EGR pipe that runs around behind the block that can occasionally rot through close to where it attaches to the manifold making similar sounds or crack open during movement of the manifold. My understanding is that pipe is difficult to source and may require some custom welding, so be prepared for that possibility.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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Alex, more information required!!
If it ticks at idle (tickover as we call it - the clue is in the name,,,) then it could be valve noise. My 945 (1991 B200F with circa 300k miles) began to tick a while ago. Valve clearances are all OK so just wear I guess. I can live with it.
Another possibility if it is louder could be a cracked exhaust manifold.
You need to have a good look and listen under the bonnet/hood to check for engine noises.
Ian F
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Agreed. My previous 245 (same engine) developed the same symptons which turned out to be a blown exhaust manifold gasket.
I sounded somewhat like as if the engine had gained an extra cylinder.
I took the manifold off struggling with rusted nuts and bolts and snapped one stud on the head and one on the flange end.
The stud could be removed by locking two nuts together and the manifold was sent to a shop to have a new one fitted (which also needed a helicoil) and the mating surfaces machined flat (the manifold had slightly curved leading to the leak).
It took some time, but I never had to go back in and do the work again.
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Hi,
A 240 man here, but that ticking sound might be your first sign the the engine is now officially “broke in!” (:-)
Being over 24 years of age means the youth days are over and it’s starting its middle aged era!
Just like us humans do! It emulating its heritage! (:-)
Maybe the universal joints are just a hair dry and a shot of attention in that area might help?
Since you said it does it mainly under acceleration and no mention of noise during an idling period of cold or hot.
Could it be a driveline noise? The Background noises drowns it out?
While comparing our cars to our frailties and of course any injected characterizations,I’ll add this to the wonderments!
People hurt worse it they sit too much and dry out if in the sun, the same.
Was the car outdoors a lot?
Phil
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Hi All,
Tonight, I decided to use my wall inspection camera and take a look right under the joint between the turbo and the exhaust manifold.
I have taken multiple pictures, some with the inspection camera, some others with my phone pointing to the mirror I placed under the turbo.
What I need to know is the following:
1) Do you think this is the reason why the engine is ticking?
2) If yes, how do I fix it?
3) I think I should remove the whole turbo block, but from the pictures it looks like the gasket is not the only problem, as part of the turbo collector is corroded.
I am aware that it is difficult to diagnose by looking at some pictures, but I am pretty sure this is the cause of the problem.
I have zipped all the pictures I took in the folder below:
https://www.mediafire.com/file/foxeemrgli1srwy/Exahust_Manifold.zip/file
Thank you for your help.
Alex
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Hi all,
Did anyone have a chance to take a look at the pictures I linked in my post of the 29th?
Thank you!
Alex
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Alex, I didn't as I couldn't open them easily. You could upload to the forum image library?
Ian F
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Hi Ian,
I see that Amarin kindly uploaded the photos I took. Thank you!
Honestly, I have always used a different server for images because it is not clear to me the process to upload them on this site.
I see Amarin did it 'one by one', so I think it is not possible to upload a .zip.
Anyways, I would like to have your opinion on what you see.
I think corrosion is the root cause of my 'ticking' lady :)
I hope to find the time this weekend to disassemble the turbo, first I need to spray with PB Blaster the 4 + 3 nuts and pray I do not snap them, that is the biggest challenge I think. I have already sprayed the nuts I can see, but I need to find a way to extend the spray straw to get to the others.
Best,
Alex
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Hi Metallo,
You're right the corrosion might be causing these gaskets to fail. Its normal for gaskets to fail after a long long time. The metal content of the gaskets exposed to water vapour in exhaust gases year after year.
Replacing them take some bit of work. Start by using some penetrant (like WD40) to the bolts BUT don't use them too much. I had my O2 sensor failed (with CEL) when some got into the exhaust pipe after I replaced mine years ago. Yes too much WD40 could clog the O2 sensor. This I only know after putting back new gaskets and start the car. So take care there.
By the way, I revived back by the O2 sensor by burning the tip until red hot at the kitchen stove. Just to let you know.
Amarin.
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Dear Amarin,
Hope you're well and stay so!! I think PB Blaster would be more effective than is WD40, to help loosen heavily-corroded exhaust manifold nuts. PB Blaster is formulated to penetrate the micro-channels in corrosion, and so to weaken the corrosion bond.
PB Blaster is available in Malaysia, see: https://shopee.com.my/PB-Blaster-Penetrating-Catalyst-311g-i.9148574.9953408251 ) . At MR80/can, it is not a "cheap date". But a can should last a long-time. And if using it prevents a broken stud, it seems to me to be worth the money.
Before applying PB Blaster, I use a hand-held high-speed rotary tool - with a stainless steel brush - to remove as much as possible of the corrosion on the stud end, that projects from the nut. Cleaning the stud-tip helps the PB Blaster to penetrate. I saturate the eight nuts repeatedly over several days.
I then turn the nut as if I were going to tighten it. A movement of a few hundredths of a millimeter suffices. I then reverse and gently "rock" the nut, until it starts to move. I've done this to change two sets of exhaust gaskets, so far without snapping a stud.
Hope this helps.
Stay Well!!!
Yours faithfully,
Spook
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Hi All,
I lifted my car on my cribs and went down.
The good news is that there is no corrosion as it seemed from the previous pictures. It is really a visual effect, I can scratch away the black dirt with a screwdriver, there is no hole in there.
However, the carbon-type discoloration at the joints could signify a leak.
Please see the pictures, my apologies, they came up too big, I wanted to delete and re-upload them reduced, but I cannot see how to delete the existing ones.
In the meantime, I put a rag in the tail pipe, turned the engine on, went down and yes, I can confirm smoke is coming out from both the joint with the downpipe and the joint turbocharger-exhaust manifold.
So my conclusion is that the issue is caused by the two gaskets, what are your thoughts?
Alex
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Dear Amarin,
Hope you're well and stay so. These photos show the gasket is "gone"! If the ends of the bolts are wire-brushed to remove corrosion, and then the bolts/nuts are repeatedly saturated with PB Blaster (or similar penetrating oil), gasket replacement should be relatively straight-forward.
Stay well and Happy Holidays!
Yours faithfully,
Spook
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Hi Spook,
I guess you refer to both gaskets right?
Turbo to exhaust manifold
and
Turbo to downpipe.
I did follow your advice, soaked with PB Blaster for 4-5 days in a row and the downpipe nuts came out without any problem.
I will work on the rest this afternoon, more questions:
1) Do I really need to drain the coolant system? Couldn't I simply plug the rubber pipe once I remove it from the turbo?
2) I would take this opportunity to change the exhaust manifold gaskets too, anything else I should change given that I am on it?
3) I tried to find the P/Ns of both gaskets "Turbo to exhaust manifold"
and "Turbo to downpipe" but I cannot find them. I am searching the category 25 in VIDA but no luck. Can you help?
Thank you!
Alex
Alex
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Dear Metallo,
Hope you're well. As I've never owned and so worked on a turbo-equipped 940, please tell me if your car has a single down-pipe from the turbo all the way to the catalytic converter, or if the down-pipe in a "Y" format, i.e., has two arms that join just before the catalytic converter?
Stay well!!
Yours faithfully,
Spook
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Hi Spook,
As per image below, there is only one pipe. You can see that I removed the nuts already.
I did drain the coolant and I am almost done disconnecting all the pipes from the turbo, there is more staff than I expected really.
I was also able to push back the flange from the downpipe, but obviously, until I do not undo the nuts that keep the turbo attached to the exhaust manifold,I will not be able to see if there is a gasket between the downpipe and the turbo.
I hope there is, otherwise I cannot explain the leak from that area too.
Thank you,
Alex
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Dear Metallo,
Hope you're well. As I've not worked on turbo-equipped cars, I'm guided by the diagrams in Volvo VADIS, a superseded dealer parts/service database.
the diagrams do not show a gasket between the down-pipe and the turbo housing or between the turbo housing and the exhaust manifold. I presume these metal-to-metal joints are ground precisely and so are leak-proof.
So, any exhaust leaks there result from corrosion.
Based on some quick "research", I find a product - Silkolene 762 - engineered to stand-up to the super-high temperatures in a turbo application. An eight-ounce tube is about $125. I've never used this product, so can't assess its durability, etc.
This product is intended for joints, where there's no movement, as it has no elasticity. The heat "cures" it rock-hard.
I think I should "hand-off" this issue to someone, who has hands-on experience with turbos.
Hope this helps.
Yours faithfully,
Spook
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Yes, I confirm that there are no gaskets.
In addition the exhaust manifold gasket kit P/N 271704 has been discontinued.
I will have to go for Elring, but they are difficult to find here in Canada.
What would you recommend as an aftermarket top quality brand?
Is Victor Reinz any good?
What's the best way to clean the turbo (externally) and make sure joint is perfectly clean two?
Thank you,
Alex
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Hi Alex,
I would like to suggest you try industrial and bearing supply houses in your area.
It’s a shame that Volvo didn’t use a standard exhaust donut bring for that!
Ask about a gasket companies and products in compression gasket commodities.
These are made of carbon or graphite with fiberglass webbing.
Over my years ago I dealt with a global company called “Garlock.” Their huge!
I’m sure there are plenty of catalogs and representatives to guide you to getting what I call “packing rope” that you can cut to fit the inner circle of the flange.
The stuff can be cut to overlap ends!
This company also makes high temperature, flat gasket materials or have contacts to standard made shapes that can be purchased over the counter by a part number!
It’s the best way and to go is keep things standard to fit in the space needed or make the space fit standard!
Be flexible and you will be surprised what’s out there in the woodwork!
Phil
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Hi Spook,
Hope you're well too. Thanks for the tip. I'll give it a try. I agree at RM80 (RM is Ringgit Malaysia ie the currency) is not cheap by average Malaysian standard. Its just I don't use Shopee as much as the next Malaysian as it always disturb me by its sale ads during youtube viewing. Well we all have our pet peeves. Anyway no worries here!
Stay well! Stay safe!
Amarin
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Hi Spook,
Thank you very much for your advice.
I was able to spray with PB Blaster all the nuts during the last three days, all of them but the lower one of the downpipe which I can only reach from under the car.
So, on Saturday, I will lift the cat on my cribs and spray the remaining nut.
In the meantime, I will empty the cooling system, disconnect all the pipes that are going to the turbocharger and perhaps, I will try to undo one of the nuts to see what happens.
Fingers crossed.
Thank you!
Alex
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Coming to this a little late. I've had good luck taping the blower portion of my shop vac to the tail pipe and examining all exhaust system joints. If any are leaking you will feel the air flow w your hand.
Marty
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Well, my 940 is normally aspirated, not a turbo, but that certainly looks like it could be the source of your ticking noise. Either way it needs sorting out.
Ian F
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Hi,
Since you want to extend the spray from the spray can you can use a piece of wire insulation to slip onto the spray tube that came with the spray can.
I also use short pieces to connect more than one spray tube together to make the sprays go farther!
I usually find a 12 or 14 gauge solid copper wires insulation works to fit the tube into.
If you need a really long piece, you might need to warm the wire coating up a little bit to help get it to slide off easier.
Phil
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