Author Topic: Need Timing Help (Read 6248 times)

Murdul · « **on:** August 26, 2009, 05:50:41 PM »

I replaced the right and left timing chain guides on a 91 318is this past weekend and did three things wrong. The car will not start need potential damage.

1) Rotated crank shaft backwards at least two rotations before I removed the crankshaft bolt. The chain was still on, I'm talkling about before I removed the pulleys, just getting close to TDC. Does rotating the crank backwards cause damage?

2) When locking the flywheel I pushed some of the plug through. I was unaware any was left in the hole, and when I pushed my drill-bit through I pushed the plug in.

3) Attempted to start the car with spark-plug wires in incorrect order. I know I'm dumb for this.

Those are the things I did wrong. I did lock the camshafts and crank, nothing turned while I replaced the guides, I replaced the sprockets excactly as they were, I installed a new tensioner as well, I unlocked it before I installed it.

As of now the car will try to start, but never does. The starter spins the flywheel and the crank, but after about 2-3seconds the crank stops spinning and only the starter turns over. What I am trying to find out is if I caused catastrophic failure.

Thank you.

bmwman91 · « **Reply #1 on:** August 26, 2009, 06:48:19 PM »

Did you ever try to turn the crank and have to force it to move? If things somehow got way too far out of alignment, you would end up with pistons hitting valves. Many years ago on my first M42, I did the timing job & things got misaligned to the point that the motor ran, but was hitting valves. Somehow it never caused damage & it ran fine.

When it turns over, are you hearing any abnormal noises? Pistons hitting valves sounds a lit like a diesel motor running, which can also be confused with really really loud lifter slap. When you say that the starter goes, but the crank stops...what do you mean exactly?

I would not worry too much about the piece of plug you pushed into the bellhousing, it won't get into the motor. Also, hooking the ignition up wrong should not be a big deal...worst case you would get heavy backfiring & have blown apart some stuff in the intake, but you would probably know. You might have also had some knock, but it would have been very brief before the motor stalled.

Any check engine lights? Perhaps you just forgot to reconnect the crank position sensor?

Murdul · « **Reply #2 on:** August 26, 2009, 09:39:34 PM »

I did hear some pretty loud slapping the first time I tried to start the car, but I stopped and poured a little oil down the chain sides which cleared that up.

What I mean about the starting is the starter turns over, but nothing else does, the starter just spins. The starter will catch and turn the crank and turn the engine over when I first turn the key over, but after holding it for a few seconds, the crank no longer turns over, I just hear the starter spin and crank does not.

nicknikolovski · « **Reply #3 on:** August 28, 2009, 08:50:20 AM »

As far as the timing is concerned. What you need to now do, is remove the drive belts and have good access to the crank bolt. Then get your ratchet and socket and try and rotate the crank clockwise. Go slowly and feel for any binding or knock. If the crank rotates and is free of any binding, lock-up or knocking noises.

If crankshaft rotates by hand is free of any noises, then proceed as follows: Try and rotate it until you get to Cylinder 1 TDC. Insert the flywheel pin and leave it there. Take the valve cover off and check that your camshaft timing is ok. The cam lobes on cylinder 1 should point in toward each other slightly and the square ends on the end of the camshaft should be parallel with the top of cylinder head surface. If the cam timing is out then you will have to rotate each camshaft in the direction they need to be. But to adjust the cam position, the chain needs to be off. If you have got to this stage let us know.

However,

If the crankshaft doesn't rotate at all:, Then forget it, the vehicle will need an engine. If noises present then the cylinder head will need to come off at bare minimum just to inspect the damage. (Bent valves for sure and maybe piston damage)

Murdul · « **Reply #4 on:** August 28, 2009, 10:03:44 AM »

Thanks for the reply. I will look into it this weekend.

B318M42W · « **Reply #5 on:** September 01, 2009, 08:22:01 PM »

Also, maybe your battery is dying and doesn't have enough power to keep the starter engaged. try boosting the car?
On the timing side, it is possible to change the camshaft timing without take out all of the chain. just undo the 4 sprocket bolts and rotate camshaft carefully. don't forget to identify where the pin on the sprocket goes.

nicknikolovski · « **Reply #6 on:** September 02, 2009, 04:15:15 AM »

Quote

On the timing side, it is possible to change the camshaft timing without take out all of the chain. just undo the 4 sprocket bolts and rotate camshaft carefully. don't forget to identify where the pin on the sprocket goes.

I didn't know this "B318M42W". What I meant was you just take the chain off the camshafts, not completely off. But thanks for the info anyway.

Murdul · « **Reply #7 on:** September 02, 2009, 05:17:02 PM »

I haven't had much time to work on it. I did rotate the crankshaft and it freely rotates by hand and did not bind up. But if I already bent the valves this would be true also, wouldn't it? One thing I didn't note above is the sparkplug wells had a lot of oil in them when I pulled the motor apart initially. I will check the timing one more time, and then check my spark. Hopefully I can get it running again.

Sean_318is · « **Reply #8 on:** September 03, 2009, 08:15:55 AM »

Quote from: Murdul;77785

One thing I didn't note above is the sparkplug wells had a lot of oil in them when I pulled the motor apart initially. I will check the timing one more time, and then check my spark. Hopefully I can get it running again.

Can't help on the timing but: Possibly just the cam cover seals under the plug holes? Easy fix if it is, pull the cover and replace the seals.

Murdul · « **Reply #9 on:** September 03, 2009, 09:41:27 AM »

Its not the seals, its the bolts, all but maybe 4 of them are stripped, thats another project. The seals are brand new.

Yesterday I put it at TDC and found the exhaust camshaft was off by the exact amount of adjustment within the sprocket itself. So I lossened the sprocket and aligned the camshaft so it was square. Tried to start and it did for about a half second. But it deffinitely sounded like a diesel. Left it until today I will see what I can do.

Murdul · « **Reply #10 on:** September 10, 2009, 08:57:53 PM »

After several small adjustments of both cam shafts the car starts. I never took the sprockets off, I just loosened the bolts and rotated the camshafts a bit so that they were square in the rear with one another. I started it and let it run for about 3 seconds before I shut it down. Pretty glad it started, but I think she's toast. I am hearing what sounds like knocking. I'm guessing the valves are bent for sure.

Am I right?

B318M42W · « **Reply #11 on:** September 10, 2009, 10:31:01 PM »

there is a cam sensor that, i think, controls spark... if you are somewhat off by more than IIRC 3 deg, the ECU won't like it much. and also, diesel sound is normal after a chain replacement. the tensioner need to build up pressure. some ppl say to rev it to 2000? RPM for 30 sec or so to build up pressure. i personally think that your valves are most likely fine as the car started. easy way to determine if valves took a hit: do a compression test! bent valve=lower compression. ( #'s vary from 190-225 psi)

good luck

Murdul · « **Reply #12 on:** September 11, 2009, 08:24:49 PM »

Well gave it a shot, she is not quieting down. She has a lopy idle and the knock and smoke coming out the tail pipe. She is running though. Any ideas are appreciated.

Thanks

Edit Actually my engine sounds just like the video on Youtube of the M42 after rebuild that was not getting Oil to the head. What would cause this, and what was the fix, anyone know?

nicknikolovski · « **Reply #13 on:** September 11, 2009, 11:13:57 PM »

Do a compression test to check for valve damage.

B318M42W · « **Reply #14 on:** September 12, 2009, 12:17:51 AM »

primed the oil system? oil in the engine?
to prime it: remove all spark plugs, unplug fuel pump, and crank her over for about 5 seconds. then wait a little then do it again until the oil pressure light comes off. ( if you crank it too much at once, you might overheat your starter= damage)