How many of you adjust your own valves, and how often?

I haven't done this since the mid 1970s on a Datsun 240Z, and it could be done with standard mechanics' tools because the SOHC operated the valves using rockers. All my cars since then have had hydraulic tappets, requiring no adjustment. According to the FAQ, the 740's valves can only be adjusted using special tools and special shims, like a Jag or Ferrari.

The 740 I recently bought has about 470,000 km on it, but runs reasonably quietly, with no alarming rattles. I have the original maintenance record book up to 240,000 km plus a notebook and some receipts up to the present time. According to the owner's manual it looks like valves should be adjusted every 30,000 miles (48,000 km), so I presume the dealer service done for the original owner up to around 180,000 km included doing the valves, even though it's not mentioned. However, there is no mention of valves in any other entries up to the present time, even though trivial stuff like filters, plugs and oil changes are noted, and of course, bigger stuff like brakes, suspension, water pump, timing belt, etc.

So, what I'm thinking is that the valves were never adjusted in the last 290,000 km (180,000 miles). I don't think that's such a drastic assumption, because nobody adjusts valves these days except on motorcycles, or when they have their high priced mechanic do it on exotic imports.

Okay, my question is, do my valves need to be adjusted ASAP to avoid imminent disaster, or can I put it off until I get around to it? Also, is the 30,000 mile interval critical, or do you let things slide once the motor is past 180,000 miles? What is the flat rate for adjusting the valves by a shop with the right tools?

One trick I learned with VW's a long time ago, identical head setup, is to use an air blow gun, preferably with a rubber tip, right in that little slot. A quick burst of air, with a rag holding over the disk, will usually pop it loose from the hydraulic seal the oil gives it. MUCH easier task.

Otherwise it's a silly PITA, luckily it don't need to be done often. Shoot for loose, they wear tighter over time.

So ... you'll have to measure your clearance gap to begin with and then remove the camm and measure the thickness of the existing shim(s) that are out of spec. After you've determined their thickness, some have it stamped on them but you can't be sure, you'll have to locate another shim of the correct thickness to make up the difference. That's why this is usually a dealer/service procedure because they have a supply of different thickness shims. Unless you have that at your disposal you'll have to order new ones and wait. BTW you probably should remove the buckets and replace the valve stem cushions. They've probably worn out long ago. So unless the gaps are really out of spec I'd just let it go.

Just curious, is there a picture of these shims available anywhere? Can they be stacked? Could you make them out of steel shim stock?

They're just machined metal discs of various precise thicknesses. Definitly are NOT designed to be stacked. If Volvo doesn't make one thick enough for your engine then the camm shaft is probably worn out. But this is very unlikely. I've managed to pick up a bad full from various engines I've come across in the local PYP yard.

Looks like something I could make out of tool steel or drill rod and surface grind both sides to thickness. Or are they dimpled as well?

They are not dimpled.

They are 33mm +or- diameter.

Probably a particular hardness that has a small margin of error (guessing).

You can buy them for $2.25 at FCP Groton.

Even if you had the material, a lathe, and a surface grinder..........?

Makes sense. Not worth my time to make the shims and at that price, eight of them are less than $20. If I couldn't scrounge the material, it would cost me more than that to buy it. I just recently received some bits from FCP Groton and was pleased with the fast delivery and the fact that even though they used UPS, I didn't get raped for any cross-border brokerage fees or taxes.

Ops...I mean "BAG full".

That's a good idea to grab shims from junkyard. I also want to get practice taking a cam apart, so I can do that this weekend and get two birds stoned at once.

Thanks for all your help. I plan to dive into this job tonight.

Adjusting the valves may or may not be necessary. You won't know until you check them.

This is an easy process involving a set of feelers gauges and rotating the engine until the cam lobe is nearly opposite the follower on the valve you are currently checking. The specs are readily available but my Bentley's is in the garage; memory tells me .014-.016" cold.

If they are a little loose (couple of thousands over) I don't worry about them. If they are a couple under (tight) I will probably swap in a shim to loosen them up a bit.

I adjust mine when I am changing the timing belt. I simply remove the cam after deciding what adjustments need to be made and adjust those in need. I have used the tool designed for the procedure with the cam in place and I find it to be a real PITA.

When removing or reinstalling the cam it is important to loosen/tighten the nuts a little at a time so as not to put an uneven load on the cam (possibly breaking it). This is talked about in the FAQ's.

I wouldn't worry about adjusting the valves until you see if they are out of specs. My experience is that the red block Volvo engines seldom need adjustment if the valve train has a goodly number of miles on it.

Randy

300,000 miles valve clearances within spec. How do I know - had to replace head gasket and was in there. However, did replace rubber dampners under followers as were smashed - much quieter at idle. Seems you can't kill the RED brick.

1988 740 GLE

Today at the junkyard I found an engine that someone started taking apart, so I finished removing the camshaft to learn how they are put together. Seems like the distributor pretty much has to come out as well. Anway, yes I found that once you have the camshaft out, you can pull out the follower cups with your fingers. But it is frustratingly difficult to separate the shims from the tops of the followers. I had to use the point of a utility knife to separate the shims at those little notches cut into the top rims of the follower cups to get them off. Now I have 8 spare shims and am familiar with how these things come apart.

But it is frustratingly difficult to separate the shims from the tops of the followers. I had to use the point of a utility knife to separate the shims at those little notches cut into the top rims of the follower cups to get them off.

So you can imagine how difficult it might be to remove the shim using the tool that compresses the follower to supposedly allow you to remove the shim?? This is why I simply remove the cam; I find it much easier to do it that way.

You can use a micrometer to measure those shims you scored and hopefully you will have the ones you need for any adjustments.

Randy

Agreed. However, I do have one big reservation: What is the exact torquing sequence for the camshaft bearing cap nuts? I do have a brand new torque wrench (with a fresh calibration) so that won't be an issue. But I am concerned about tightening them in the incorrect order, to the right torque, and the correct torquing sequence (for example, 30 in-lbs for all of them, then start over and go another 20 in-lbs (this could be the case if the intention was to avoid crosstalk between the caps and along the shaft)).

Or are you supposed to use a torque angle gauge? I do have one of those too.

I know this is all mentioned in the faq, but if possible, if someone has the actual factory repair manual I would love to see a scanned copy of that page. I'd really love to have the book but I don't know where to get one besides that volvo technical info webpage, and I don't understand what exactly you are getting for each of those listings on there.

Finally, those rubber valve stem seal things (or hushers as someone called them), do you just take them off and put new ones on or do you have to compress the valve springs and fiddle with the keepers to replace them? Taking apart that one today I found that all of them inside there were crunchy and came out by simply picking them up with your fingers. And if I go to the dealer to get new ones, what should I ask for? I"m sure he'll look at me funny if I say I need hushers.

I hsould mention too that before taking my car apart, when I drove it there was a distinct ticking sound, noted by both a mechanic acquaintance and the previous owner. He thought it was valve lifters, but there aren't really lifters on this thing, at least not what I would consider lifters as compared to a pushrod engine. It must be excessive valve lash in one or two of the valves. It would be extremely satisfying to alleviate that noise all by myself.

It's too late for this right now and I can't think straight because of all the turkey... (it's Thanksgiving in Canada this weekend)

I have never seen a sequence for torqueing the nuts. I just get them all started on and then start from the center. I work my way out towards the ends much like head bolts would be torqued. Working with a rachet I give each nut a full revolution and then start back at the center repeating until they snug up. I then give them half of the final torque and finally torque them to specs.

The hushers simply push on the end of the stem. They are also called dampers.

Randy

I have to check mine too, and I will try to do it tonight. Today my crank holder tool 5284 finally came from IPD, so I can finish the timing belt replacement.

With Randy's experience concluding that the IPD rental tool is more trouble than it's worth (am I interpreting that right?), then I will try the alternate method, removing the camshaft. Seems like a scary thing to do. I will study the faq first. Do you have to replace the camshaft oil seal when you take out the camshaft? Fortunately I have a new one on hand, but it's the red kind, made by Elring.

Now I wish I had taken apart some camshaft assemblies at the junkyard on the weekend.

concluding that the IPD rental tool is more trouble than it's worth (am I interpreting that right?

The tool I used was not like the one from IPD. It was the type that levered under the cam against the edge of the follower. Sometimes the shim is difficult to remove from the follower; seems the oil between the shim and follower creates a suction. I don't know if the IPD tool is easier or not.

With the timing belt removed (remember I try to do my adjustments when I am changing the timing belt) it is rather simple to remove the cam. Although on the 7/900 series with the distributor on the cam you probably need to remove the cap and rotor to make it a bit easier.

Randy

Randy, thanks for the tip about removing the cam to avoid using the special tool.

When I bought the car I asked the mechanic that did the government safety check to look at the timing belt and he replaced it because it had gone 100,000 km, so I won't need to touch it for some time.

What is the easiest way to turn the engine for checking the valve clearances? Can I use a remote starter switch? Can it be done with a socket on the crankshaft pulley bolt with the plugs removed, or do I even need to remove the plugs?

With the plugs out you can rotate it by hand using the crankshaft pulley, but if you have the correct sized socket it is easiest to use a ratchet.

Randy

Point 1. Valve seat recession - Valves do need adjustment but not often due to seat erosion. My 240 has 518,000 km and last had valve shims adjusted 10 years ago at 370,000 km. Since the job is very tedious you can get away with only doing the exhaust valve shims as they get most erosion. For example my cold clearances for valves 1 (front)to 8 (rear) in sequence were less than 1.5 thou(smallest feeler gauge leaf), 12, 6, 12, 4, 11, 12, 13 thou. Note the huge difference in recession between exhaust valves for cylinders 1 and 4. Also worth noting is that I ran my 240 on LPG since 1991 which is supposed to cause more valve seat erosion than gasoline. Compression on cylinder 1 is fortunately OK (100 psi (cold)) but I think I came too close to burning #1 valve and having the car towed to a head shop for an expensive fix. BTW I have never used upper cylinder lubricant (eg Flashlube) with LPG. Although there are horror stories about valve recession on the Internet at least Volvo (240) valves and seats must be tough to do 300,000 km on LPG and still work.

Point 2. Adjustment tools - Its possible to use homemade tools to replace shims. To depress the cam bucket I used 2 screwdrivers, one to initially depress bucket and then the other to hold it down at the edge of the bucket after removing first screwdriver. The main hassle with this is that inserting the first screwdriver rotates the bucket sometimes "hiding" the slots that are used to grab the shim, so use another screwdriver in the slots to rotate bucket to get the slots in a good position. To remove the shim use a small pointed screwdriver and bend its end 90 degrees to poke in the bucket slots. Since the oil between the shim and bucket provides some suction against shim removal I found that it was easier to get better shim extraction with a tiny flat blade screwdriver than a pointed one, though I used a stone to grind the blade edge very thin to get into the gap between the shim and bucket.

Point 3. Cam rotation limitations. To remove several shims its necessary to rotate the camshaft but rotation is very limited since the cam lobe goes right down into the bucket and then the top of the cam lobe will jam against the edge of the bucket limiting rotation. Nevertheless I extracted 3 shims with this partial rotation though I found it necessary to turn the engine both forwards and backwards to do so.

Point 4. Mechanic cost - After doing this job (at no cost but considerable stress) I spoke to the local mechanic about his cost of doing this job. He said it would take him two and half to three hours for all 8 shims at $100 per hour labor - presumably with Volvo special tools. The he said why dont I do it myself because the job is not easy, and then he said sometimes he pushes this job out to a "head shop" - I guess he has a gofer drive the car to the head shop then takes his cut for doing nothing. Before you start this job make sure you are in a good mood with plenty of patience as you'll need it.

sutherml @ Adelaide, Australia
1979 244 @ 518,000 km
Converted to LPG in 1991

"Before you start this job make sure you are in a good mood with plenty of patience as you'll need it."

Well I'm rarely in a good mood, and I have no patience for anything at all...

But thanks for the tips. Unfortunately at this point since I haven't actually taken it all apart yet it's hard to visualize what you are talking about. As soon as I get into it I'm sure I'll understand.

Seems it would be alot easier to just loosen up the timing belt and take the camm out. You'll need to do this anyway if you replace the stem cushions.