91 318i, pulled my valve cover, pics enclosed, is my timing OK???

[90pioneer]

1991 318i, 178k, recently purchased. Last night the car ran great for 9 miles, shut it down, started it up 15 minutes later, and it shakes very badly, sounds awful, hardly runs, but gets a little "better" over 3500rpm. Engine is missing significantly.

Guy in my other thread suggested I pull the valve cover and see if my timing chain jumped a tooth. Well I pulled the valve cover off, everything to me looks clean and in good condition. The teeth don't show hardly any wear...

I can wiggle the chain with my finger but not much. Another member said there should be arrows on the chain or sprockets that point to each other to tell you when the timing is on. Well I don't see any arrows or marks indicating where or what exactly needs to line up.

Here are the pictures:







What do you think???

[dude8383]

The teeth look good the sprockets... doesn't mean that the guides are in great shape though.

[90pioneer]

The teeth look good the sprockets... doesn't mean that the guides are in great shape though.

So now what do I do?? How can I check to make sure the timing is correct?


What else could make the engine go from running great to awful?

There are no stored engine codes. All the spark plugs look good. Also despite it running like crap, the timing chain didn't appear to be making any noise??

[dnguyen1963]

Man, did you check for vacuum leak before doing all this work?

[roguetoaster]

Timing on the M42 is verified in 2 ways, if both line up timing is good, the only reasonable adjustment you can make is to the cams. Cams, when the rear square sections are flat (use a straight edge across them) and the front two lobes point up and at each other like / \. Crank, when the arrow on the block points to the window (missing area or teeth) on the crank sprocket/vibration dampener. Start by rotating the engine to TDC at the crank, then lock the flywheel (with an 8?mm device, like a drill bit), then look at your cam timing, adjust by rotating the cams.

Hard to know why the car is running poorly now, was it sitting for a long time before you drove it?

[roguetoaster]

To add, if you want to check to see if your guides are good, you either need to pull the upper timing cover (best) or remove the lower pan and look for bits of plastic. I would think that your guides are in good shape as your cam gear teeth look fairly square. My bet for bad running is a bad coil/driver or bad fuel/fuel shortage.

[Dj Buttchug]

the engine didnt jump time. op dont waste youre time checking timing. thats not the issue here.

Check engine managent things first. just cause you have no mature codes doesnt mean you crank sensor isnt shitting out.

dew work.

[90pioneer]

I found the problem. The number 4 spark plug cylinder gasket failed and puked a bunch of oil up into the spark plug tube that goes between the wire and the plug...

[mangomango]

Timing on the M42 is verified in 2 ways, if both line up timing is good, the only reasonable adjustment you can make is to the cams. Cams, when the rear square sections are flat (use a straight edge across them) and the front two lobes point up and at each other like / \. Crank, when the arrow on the block points to the window (missing area or teeth) on the crank sprocket/vibration dampener. Start by rotating the engine to TDC at the crank, then lock the flywheel (with an 8?mm device, like a drill bit), then look at your cam timing, adjust by rotating the cams.

Hard to know why the car is running poorly now, was it sitting for a long time before you drove it?

Question, and i did not want to start a whole new thread on it. I just

replaced all my timing gears and chain and guides but, when i opened up

the motor for the first time I was getting it lined up to square it off and

lock everything down, I found that the two square ends that you'd put the

cam locking tool on didn't line up flat. The cam closest to the drivers side

was rotated a small amount so that a straight edge would not sit flat on it

when placed across both ends. So my question is, should I loosen the cam

gear bolts and rotate the cam itself so it lines up with the other one?

[Massimo]

Probably best to keep them that way then. Could be a correction from new. When I did mine I didn't use the cam tool. I simply marked everthing. like so

Cam to sprokets
Sprokets to chain

Once I did that I pulled everything off. I had a new chain so I found the same space between the chain links that I marked on my old chain and marked the same spot on the new chain.

As long as you mark everything and keep the engine at TDC there will be no issues. If you want to get particulart you can run a strair ruler along the two sprokets and draw a line across them and across the cams. Then when you put everything back on as long as thoughs lines match the ruler you are all good.

[Mc85]

knowledge

i noticed mine have a lil oil in the sparks as well, mainly the first.. i myself never done work past replacing a the vc gasket.. how is this problem resolved..

I found the problem. The number 4 spark plug cylinder gasket failed and puked a bunch of oil up into the spark plug tube that goes between the wire and the plug...

[Massimo]

i noticed mine have a lil oil in the sparks as well, mainly the first.. i myself never done work past replacing a the vc gasket.. how is this problem resolved..

Simple as. Simple remove the valve cover. Which requires removing the bolts and the hose. remove old gasket, clean area, reinstall cover. The only hard part is not tightening the bolts to much. Simply tighten them till the rubber washer has been squashed.

Thats it, would take about 30min.

[vpilarrt]

The VC bolts on an M42 have a step so you tighten them down all the way and the spacing on the bolt squashes the gasket the right amount. Just be careful not to over-torque the bolts and strip the threaded holes in the aluminum head - just good and snug.

[Mc85]

cool... i wasnt sure if that would fix it... so i guess i need to buy a vc gasket kit..

[mangomango]

Probably best to keep them that way then. Could be a correction from new. When I did mine I didn't use the cam tool. I simply marked everthing. like so

As long as you mark everything and keep the engine at TDC there will be no issues. If you want to get particulart you can run a strair ruler along the two sprokets and draw a line across them and across the cams. Then when you put everything back on as long as thoughs lines match the ruler you are all good.

i didnt have the locking tool i just used two big adjustables and criss-crossed them with a c-clamp so they wouldn't move. and the flywheel locked with the drill bit thing hole thing.

I've had it running since the new parts were installed and it runs great in the higher rpms but is a little finicky down low.

I just thought i had read somewhere that the two square ends on the back of the cams should line up with eachother. The PO could have done this too, it already has the 4 pintle mustang injectors installed so that was a nice surprise. too bad they're extremely dirty