M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: arcter on February 09, 2010, 01:30:05 PM
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Hey guys, I own a '91 318iS in very good condition. It always has run great but recently I've been hearing some sort of rattling/vibrating sounds coming from the engine, mostly at idle. Not very loud though. So yesterday morning I go out to start it and it just stumbles and dies. So I had it brought to my mechanic and he says that the timing chain 'jumped time' and so I'm looking at a timing chain / hardware job. Does that sound right? I trust the mechanic but I just have never heard of one doing something like that so early, considering the noise wasn't so bad. He says the engine is fine, is it possible for it to jump time and not damage the engine? It was not running when this happened, it just died immediately upon trying to start it.
Any thoughts? Thanks!
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Yes. It should not be too difficult to correct though, unless you replace the timing chain which is a huge job. He can just re-index the timing by taking off the valve cover. You MUST get a new timing chain tensioner too. Amazing it did not break a valve....
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I have one inside that did that on Fri. It bent all the intake valves. The weak link is supposed to be the long chain guide. The 4 hole, driver side guide ,sheds the skin and drops the timing off. The chain looks OK but Iam putting a new one on anyway. I will measure it, and the new one for the guy that wanted to know the diff lenght. It has about a 1 in sag held sideways by the ends. This car ran perfect right up to quitting.(300K)
Also , I will pull the lower pan and clean out that mess and tighten up the oil pump tube and stuff...
Might as well fix the oil can leak also..
If it jumped Timing, it will be about 400$ parts and about 8-9hrs labor plus the head work.(8) valves
If it really skipped all of the valves, it is about $100more.
1000$ +- is fair and the car should be good for another 200K
HTH, MM
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So it sounds like it'd be very strange if it did skip all the valves? That makes me worry that it probably did and the mechanic isn't telling me (yet?).
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There are a few ways to see if they are bent with out removing the head. Air in the plug hole is the easiest. But keep in mind that if they hold pressure that it will turn the engine some to BDC. Also pull the cam and measure the valve ends to the surface. Bent will stay down some. A good bit on this engine. The valves are about 11-12$ each
Most 16V engines with chains, hit most of the whirlygigs. IMHO. More than about 20 * late should touch the valves.
It would surprise me if none were hit. I would bet 20$ that at least 4 are.
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There are a few ways to see if they are bent with out removing the head. Air in the plug hole is the easiest. But keep in mind that if they hold pressure that it will turn the engine some to BDC. Also pull the cam and measure the valve ends to the surface. Bent will stay down some. A good bit on this engine. The valves are about 11-12$ each
Most 16V engines with chains, hit most of the whirlygigs. IMHO. More than about 20 * late should touch the valves.
It would surprise me if none were hit. I would bet 20$ that at least 4 are.
Thanks for your replies and sorry but I just want to be prepared for what I might be in for. He told me $800 for the timing chain hardware replacement stuff but if we find out tomorrow, say, that 4 valves were bent, how much money am I probably looking at altogether?
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R &R head and repair. about 5 hrs over the front end labor ,maybe less. The head itself will be extra.
Just the head is usually about 800 -1000 complete, But you have labor stack time due to the timing chain also.
So for about what the car is worth, 1300-1400 for all??
I dont get that much at 60 per hour tho. I am slow also. old anal and careful. Good luck. MM
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arcter
where are you at, maybe you can find somone local to get you some advice
you can also check r3v club and look regional
but I would be surprised if you dont have bent valves
or it could be a simple fix and the shop where your at now is hosing you
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You don't want to sell the car do you?
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You don't want to sell the car do you?
Depends what the damage was or if there was any. The mechanic hasn't had time to work on it yet but he says he's very confident it didn't do any damage this time. They've run it a few times and it idles nice and smooth.
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Lucky. MM
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That's great news!
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Thanks! 175 across all cylinders. :) Fixing some other stuff while he's in there but I should be good as new on Monday.
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Buy a lottery ticket.
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Alright guys, I got the car back. It seems to be running well but there are a few things I noticed and thought I'd post.
First of all, it sounds a little different. Whenever the engine is revved you can hear an almost "winding" sound or something. I showed the sound to the two mechanics at the shop and they didn't think anything of it, but it didn't do it (maybe just not this loudly) before. Maybe just due to the new timing chain stuff?
The other thing is sometimes when I downshift now to slow down, I let my foot off the clutch slowly and it feels similar to the rumbling you get when a car is stalling but it doesn't and the revs are normal. Stops when I get the clutch to a certain point. Any ideas?
They did a lot of work so maybe I'm just expecting too much?
As far as the other stuff goes, it now is very quiet at idle and even in the morning when it's cold. It seems to idle as smoothly as before (I actually always did have an intake leak or something that sometimes caused a funny idle) and run as well.
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the "winding" sound is normal. New chain guides will cause that winding/whining. i find it is the loudest at about 2300-3000 rpm. The new tensioner should amplify the sound.
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Ditto on the whine. The new guides look like a hard plastic. The old ones look like a hard rubber and maybe were quieter.
The clutch may have some slack in the Dual mass. It is a rubber hub that will gain some movement over use. Sometimes you have to diegrind the holes to get to the bolts. Many DMF, have a little wind up when you let out the clutch. IMHO. MM
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Thanks guys. Okay, I have two more things to ask about.
For months now, before this happened, I've had some rough cold start issues as well as a low-dipping idle. Any time the car is cold, basically, it starts rough and if I don't give it gas it'll fall really low, almost feeling like it'll stall. If I give it gas for a couple seconds, it's fine. The past couple days I've had it happen worse than before but it's basically the same. Mechanic said it's probably the fuel injectors?
The other thing is when I'm driving, and it seems to get in moods when it wants to do it. When I'm driving and I push in the clutch and let the revs fall to idle, it'll dip low and start to shake. Usually not very low but low enough to make it rumble a little. It'll then correct itself and idle fine. I've had this since before the timing chain problem too, and the mechanic has been pointed to it several times but all he's ever said is might have something to do with the throttle cable, and he's adjusted the idle a few times but to no avail. Any ideas?
Car seems to be running quite well other than these problems!
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I have a 91 is that has a similar low/stalling idel. My son now drives the car so I have not been able to isolate the problem. I believe it is from a vaccum leak. Does you check engine light come on? His does, but when I test drive it, I am not always able to duplicate the idle problem. I have all the new vaccum hoses, but just have not had time to replace these original hoses. Most of the vaccum hoses are under or hiding under the intake so hard to detect where the vaccum leak might be.
:confused:
Norm
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My M42's new to me but I've been down the Bosch fuel injection road with 80's era SAAB 900 Turbos (Bosch LH) and I'd tend to suspect your Air Idle Control Valve and related hoses.
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I just found a MAJOR leak where the FI body attaches to the upper manifold. I Just tightened the bolts on the black 318 after re-installing the FI on the white 318, really as a way to delay the rest of the work I still need to do on that car. I'm looking at the hose routing in the black car, socket in hand, and decided to snug the FI body down. Shee-it, that bolt was loose. And look, this one is MISSING. 3 out of 4 were not secure. OK, fixed it up and resolved all kinds of poor running issues. So, look there for a leak also, not just the vac lines.
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http://www.m42club.com/forums/showthread.php?t=11009
Please watch the firs movie with the idle in cold start. If your problem is the same, it may be the timing or of course the damn vacum leaks. The next week I will have all the tools necessary for the job and start with the intake: all the gaskets brand new + replacement of all vacum tubes in hard plastic with ruber connection at each end, i have found some great ones at the parts shop. The injectors have already been checked.
After this, I will adjust the timing, I shall have the cam locking tool and flywheel pin done by next week.
If your problem is the same as mine, read the post so you can see what I have tried.
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Well it turned out my cold start roughness was caused by one of the cylinders not getting the right spark. So we changed the ignition coils and whatnot and that's solved. I also fixed a couple of leaking hoses connected to the ICV and the idle problem is a lot better, though when it's cold it does tend to dip down a little bit sometimes but it's much better than it was.