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I changed the belt and seals. Everything lined up as should be. The '92 240 starts fine, idles as it did before (very low) and drives quietly, meaning no valve noise most of the time.
But even though it accelerates smoothly, it seems to have less 'oomph', plus this...
Today I made an extended trip (50 miles on the interstate battling a strong headwind), exited off into some heavy traffic up a hill. Accelerating to merge, the valve train starts making racket, and I look behind and it is belching smoke. It stops pretty quickly and quietens down... does it no more the rest of the day.
It has done this one other time, but a shorter trip. I just stopped and started back right away... up a slight rise, and the valves did the same. I did not at that time notice any smoke.
This after the belt change, and it never did this before. Should I pull it back down and recheck, even though it is generally good running?
Can the timing belt be off just a little and give these results?
Thanks.
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"Do you think that's air you're breathing now'? (The Matrix 1999) '94 940T (400K+), 92 245 (250K+K)
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Smoke and noise should not be Timing related but having the acceleration a bit doggy could be that the Cam is off 1 tooth. Remember that if you line up the marks perfectly, Put the Belt on and have a bit of slack to the Right of the Gears as you look at the front of the engine then it is possible for the Tensioner to pull the Cam counter clockwise a bit as it takes up the slack.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html http://cleanflametrap.com/tony/
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Andrew,
If you don't have a mirror, get one. Use this mirror to check the marks on the lay shaft. This is truly the only way to check to see if your marks are on.
I use one every time I do the timing belt. Works every time.
Let us know what you find out.
Matt
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"If you don't have a mirror, get one. Use this mirror to check the marks on the lay shaft. This is truly the only way to check to see if your marks are on."
Confirm by checking that the index mark found on the rim of the distributor lines up with the rotor. Positioned there gives firing at 0 degrees TDC.
Since this is '92, further timing adjustments would be made by the ECU.
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1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.
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I use a mirror, it is the best way I have found to get timing correct.
Dan
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I use a mirror also. But a cell phone camera can be handy as well. Both beat guesswork and parallax error.
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Art Benstein near Baltimore
Raising teenagers is like nailing Jell-O to a tree.
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Note to Matt.
I actually do have a good mirror, have used it another time. I was away from my home base and did not have one available when putting it back together
Thanks for the comment.
Now I am wondering if someone will reply to the question ' To understand better' related to the distributor.
--
"Do you think that's air you're breathing now'? (The Matrix 1999) '94 940T (400K+), 92 245 (250K+K)
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From your initial post " Should I pull it back down and recheck, even though it is generally good running?"
Looks like that makes the most sense. If all is well you can then start to look elsewhere. I had my belt changed recently, it was due to time rather than mileage. There have been no negatives but have to say that for a short while the car felt a bit "different" to drive and the idle seemed to be up about 25 revs but now I don't notice any difference. Happily sits at a quiet 80, hour after hour if needed. It's a '92 SE Wagon, 2 litre, in the UK.
I believe there are 2 different belts with different shaped teeth. The type needed is means this needs to be checked when replacing. I don't know which engines have what type. Fitting the wrong type may cause it to jump teeth but someone else will have to make the call on that.
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If the timing belt was all that was changed, that's the place to look first.
Greg
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When lining up the three marks, it is easy to see the top and bottom marks... the auxiliary gear mark a bit harder.
So you get it back together, and suspect that the auxiliary position might have been off a tooth. Rather than tear it all back down, could one not just remove the top cover, make sure the # 1 is at TDC ...with the mark at the cam correct ...along with the bottom pully marks being straight up, and then make sure the rotor in the distributor was spot on for #1?
This sounds right, as all the auxiliary shaft does is position the rotor in the distributor.
Is there any downside to this thinking? Waiting for sage advice! 😊:)
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"Do you think that's air you're breathing now'? (The Matrix 1999) '94 940T (400K+), 92 245 (250K+K)
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"Is there any downside to this thinking?"
It is good theory, but in practice it makes more sense to fix the belt alignment because, even if you remove the dizzy's index position lock, the range of adjustment is small and your reference is imprecise. The rotor doesn't really "point" to reference mark like the older units timed at the distributor.
The work of TB replacement is in removing the crank pulley, but you've already done that. You can check its alignment without doing that (see my response to Randy) and you can fix it easily also.
It is worth doing it right, I think. The next person to change the belt will be happy to be able to install it on the right marks.
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Art Benstein near Baltimore
We childproofed our homes, but they are still getting in.
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A racket accelerating up hill with hot engine. Sounds more like severe detonation and associated poor combustion. Check the ignition timing and vacuum hoses. It may be the intermediate shaft is off a tooth or a vacuum hose was disconnected during the work.
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I don't believe the ignition timing is controlled by the position of the distributor on this car. The ECU controls the timing and as long as the distributor is set anywhere close to the right position the ECU will sort it out.
If you put a timing light on a post 1988 red block and watch it while moving the distributor the timing only changes for a very short period of time before the ECU steps in and puts it where it wants it to be.
I don't really know the mechanics or electronics of the knock sensor, but when one is functioning correctly it is pretty difficult to have pre-ignition (detonation); once again the ECU steps in to adjust the timing.
Randy
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Randy is correct.
The distributor position will not affect ignition timing. You can't compensate by twisting it for two reasons. One, the plastic lock is meant to discourage this, and two, you don't know where to put it.
What it will do is affect whether spark gets delivered in all conditions of spark advance. When it is adjusted by the computer, the position of the distributor rotor must align its lengthy edge with the correct plug, and if it doesn't the motor will misfire.
There's no way you can see the index mark, even with a mirror, unless you remove the lower timing cover, which means you must remove the harmonic balancer.
But you can determine if it is lined up right by rotating the index mark into view and counting the teeth on the belt back to the cam index. Use a straw or chopstick to verify crank is set at TDC when cam index mark is aligned.
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Art Benstein near Baltimore
"When I grew up, it was duck and cover! Now it's ... Tuck in them elbows, boys and girls!" - Phil
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It is a little difficult to judge the timing marks embossed on a plastic cover when looking from above. You should straight on from the front of the car as best you can for that intermediate shaft mark. It is very possible that you are off a tooth or so.
I would definitely re-check those timing marks according to the book. I have done this myself many years ago.
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OK... should have said. Engine temp good (dead center; comp board removed)
It is possible axillary was off a tooth (hard to see there). I can adjust this at the distributor a bit, right?
Thanks, guys.
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"Do you think that's air you're breathing now'? (The Matrix 1999) '94 940T (400K+), 92 245 (250K+K)
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I would recheck, but it could be just a coincidence. Other issues.
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Post Back. That's whats makes this forum work.
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