John if you're reading this I tried moving the cam gear one tooth forward and one back on the '87 740 N/A. It ran much worse with the gear rotated one tooth counterclockwise but ran better one tooth clockwise from where I originally had it. The idle is now a little lower than it was ( around 800 or a little less). It starts very quickly. I went and drove it, and the power seems a little better.

Are these older non-turbo 740's just sluggish? I don't have another NA 740 to compare to. My other 740 was a 16 valve, and that car had way more power obviously. My 760 is a turbo, so the only thing I can somewhat compare to is the '91 240 wagon. The 240 has much more punch when you floor the gas.

I don't think that this would be the case, but would changing the cam timing change the ignition timing? The immediate power upon flooring the gas is better, but seems to die off at higher rpms (still pulls right up past 5,000 though).

Thanks,
Dave

Maybe check for any exhaust restrictions. Connect a good vacuun gauge to the intake manifold after the throttle body. T off any convenient line. The reading should be around 15-17 inches when idleing. Run the engine up to around 2500 rpm. The vacuum should still be pretty much the same reading. Make sure the ac is off. If the vacuum drops more than 2 or 3 inches then you've probably got an exhaust blockage somewhere.

If it has good low end punch, but wants to flatten at mid range, you may still have the cam advanced one tooth too much.

Have you aligned the crank damper mark at TDC and the cam sprocket mark to its index mark on the rear timing belt cover? (See 700/900 FAQs on this site.)

If you have the cam-driven distributor mounted on the rear of the head, it's timing is related to cam timing. If you have the distributor on the side of the engine (driven by the intermediate shaft), then you won't know where you stand with that unless you you remove the lower belt cover to verify the index mark alignment.

Well, when I changed the belt I lined all of the marks up correctly. The car was sluggish, and I got a tip that the belt was off one tooth in either direction. When moving it counterclockwise one tooth off of the ribbed mark on the cam it made it even worse. When going clockwise one tooth the power was a little better ( would rev up more quickly ). I know that the cam pulley's mark is one tooth ahead of the mark on the top of the rear timing cover now. So, I'm going to put it back so that the marks lineup and assume the problem is something else. I've done lots of Volvo timing belts and was certain that I had things lined up the first time. Sure enough they were, so it's time to try something else.

An observation from last night's test drive was that when you floor the gas, the auto transmission will downshift, but the engine is really slow to rev under load. It will pull right up to 5000 + rpms, but man it takes it a while to get there. Once again it doesn't miss at all while doing this.

Thanks,
Dave

Ditto. Quick way to check. Pull upper timing cover. Pull #1 plug, rotate crank until #1 is TDC on the compression stroke. You can check this by putting a finger over the spark plug hole and should feel air blow back. The lower crank should be lined up at 0 degrees on the lower cover. Now look back at the cam sprocket and rear cover. The dot and raised rib should line up. And yes, the n/a doesn't have much get up and go. I converted my 85 740 n/a to a turbo via the turbo bricks. Makes a huge difference.
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When I first did the belt, I lined everything up correctly. I got a tip that said I should move the cam pulley CW or CCW one tooth. Moving it CW helped a little with power, but something still isn't right. Of all the Volvo timing belts that I have changed, I've always lined the marks up and never had a problem, so I know I did this one right. My point was that I wanted to see if it really was one tooth off, and it wasn't.

I should also note that the car was still sluggish before the belt change.

Thanks,
Dave

Guess get to the basics. Plugs, wires etc. Partially clogged cat? You should have a removable plug usually in front of the cat. Have you put a timing light on it? 87 is also the wiring harness issue.
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oh and the wiring harness looks to have been updated.

The plugs and wires are new. The plug is also out before the cat, but maybe it's not enough if the cat is really stopped up. The timing is where it should be.

What shape is your harmonic balancer in? Maybe the cam is timed right but the ignition timing is off because of a slipped pulley.

Just a wild shot... :)

Shifted

That's a really good point. I actually lined everything up before I put the harmonic balancer back on ( with the notch in the dished guard that goes on before the cover ). The balancer's mark also lined up accordingly.

Thanks,
Dave

Dave,

I was the guy who was trying to tell you to advance the timing mechanically by one tooth until the idle smoothed out to 750 RPMs. I had the exact problem with my Turbo at one time and once I moved the timing one tooth into the correct position, the car ran great, the idle dropped to 750, the power came back etc etc. ..

It sounds like you have/had the same problem with yours. I was perplexed too becuase I checked the pulley alignment at the crank. There was a key in mine and it was installed and lined up correctly. Everything LOOKED like it was lined up but, it was still off by one tooth until I jockeyed it back and forth one tooth at a time until the idle dropped down to 750 THEN everything was good.

-12 TDC @ 750 RPMs is the ticket with the vacuum plugged off.

The 740 B230s that are not Turbos have no balls whatsoever, they are tanks but, they run well and have less problems than the Turbos do. My '92 740 NA Wagon is like driving forklift but, I love it.


I hope you don't waste too much time scratching your head, just drive the car.

Cousin John


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'92 740 B230F Wagon::'92 B230F 240::'86 B230FT Wagon (RIP-Parts Car):'83 320I::'79 320I::'81 320I::'74 2002::'70 Torino GT Convertible(351C)::1970 Dodge Dart GT 340::'70 Monte Carlo::1979 Dodge Tradesman B300 Custom(360)::'84 SAAB 900S::2004 Dodge Dakota

Hi John,

Yeah, I remembered that it was you. I was trying to get your attention with the post in the first place. So, you're cam mark was still one tooth ahead when you had the crank pulley zeroed?

I haven't gone back to reset the timing, but will do so. Maybe it is off now since I moved the cam pulley CW one tooth? By plugging off the vacuum, do you mean pulling the FPR vacuum line when setting/checking the timing?

Thanks,
Dave

Dave,

NOT the one from the FPR, the vacuum advance that goes from the top of the intake manifold. I think there are 3 of them, you want the top one. (I believe it is the one).

If your idle is at 750 and the car starts right up, put a timing light on it and see what you have with the light.

Yes, I am telling you that for some weird reason, the timing marks LOOK to be lined up when you put it back together BUT the car runs like crap and idles at 900 +/- 100 (or so) and the power is really bad. If I remember correctly, the timing (I think) even was right about -12 TDC (or seemed to be pretty close, even though the car was idling at 900).

The older ones, '86-'89 have manually adjustable timing by the normal distributor rotation CCW - CW method, the 90 and later (90,91,92) have an electronic timing module so even if you twist the distributor, the timing goes to -12 TDC electronically. At least that is what mine did and it is a '92. My old '86 was manually adjustable.

I'll tell you right now, if you are idling at 750 (or close to it), the car AND the car starts right up AND you have noticed improved power, then in my opinion you do not have a timing problem. I am not a professional volvo guy by any means at all and I do not try to be one. It's trial and error with me and that Timing issue I had, just like yours, drove me NUTS for a week or so.

If you think you still have power issues, I would look into plugs, injectors (I use Lucas, some say Oh No ! Don't use that) - I have had very good experiences with Lucas FI cleaner.

Also look at the TPS switch and adjust it if you need to, it helps off the line a bit if you have that switch positioned so just a slight tension cracks the throttle plate. And clean the piss out of the Throttle Body, it makes a huge difference at idle if the TB is REALLY clean, I mean REALLY clean.

If it is not a Turbo, it is like driving a forklift, that is just the way it is. The car is underpowered. But, I love mine.

That's my two cents worth.

Cousin John







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'92 740 B230F Wagon::'92 B230F 240::'86 B230FT Wagon (RIP-Parts Car):'83 320I::'79 320I::'81 320I::'74 2002::'70 Torino GT Convertible(351C)::1970 Dodge Dart GT 340::'70 Monte Carlo::1979 Dodge Tradesman B300 Custom(360)::'84 SAAB 900S::2004 Dodge Dakota

Hi John,

Well, I have to say that the power is improved over what it was.The idle was down around 750 rpm.I'll check the timing Friday evening when I get back to town. My next plan is to get the exhaust system replaced. Everything from the manifold back is bad on mine.

Since all of the tuneup parts except the distributor cap are new, I'll also try some injector cleaner. You mentioned the TPS switch, but I found a receipt from the local Volvo dealer saying that was adjusted and cleaned last summer. I'll double check, but I remember hearing it click just as the throttle is opened. It's sort of a funny story with this car. We bought it from the original owners back in 2002 and sold it in 2003. The guy who bought it from us didn't take care of it and eventually donated it for a tax write off. I saw it sitting at a car lot and bought it back for $300. Now it needs some help to get it back to where it should be.

Thanks for your help.
Dave

Good to hear that things are going in a positive direction with the timing/power. Remember, if it ain't broke, don't fix it. I think you are all set with the timing belt problem.

Anytime Dave, glad to help. Soon the snow will be melting, the wrenches will come out, and I'll be driving these people with more dunce level questions about the '91 240 I got for free.

I may not always be right but, you know, even a blind squirrel finds an acorn once in while.

Cousin John
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'92 740 B230F Wagon::'92 B230F 240::'86 B230FT Wagon (RIP-Parts Car):'83 320I::'79 320I::'81 320I::'74 2002::'70 Torino GT Convertible(351C)::1970 Dodge Dart GT 340::'70 Monte Carlo::1979 Dodge Tradesman B300 Custom(360)::'84 SAAB 900S::2004 Dodge Dakota

If you replace the cap/rotor, go with Bosch. My 85 740 hates any after market caps. I believe its something to do with the manufacturing tolerances.
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If you got your idle around 750-+, I would put a timing light on it and confirm you're getting 12BTDC, and not wandering.
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