I was wondering if anyone can shed some light on this.
This happened Saturday afternoon, was driving around not really getting on the gas. When all of a sudden the car shutdown, tried restarting it twice before I coasted to a stop. Looked under the car for leaks, looked under the hood, everything looked normal.
And then I noticed the timing belt, there was still some tension on it. But it seemed like it was coming off the cam gears, looking a little closer it looks like the timing belt tensionor spring somehow came loose and got chewed up. Also I didn’t hear any strange noises before it happened, it literally just died on me.
I guess my question is, is my motor toast? Is this type of thing normal? What could’ve caused the spring to come loose?
Can I just go back in there and replace the timing belt, tensionor, spring, and set the timing again and be ok?
You’ll have to tear into it to see if there’s any damage. It’s pretty much a crapshoot - you might be just fine and just need to redo the belt, or you may have internal engine damage. Pull the valve cover to see how many teeth skipped on the belt and how far out your timing is. If the car shut down then likely it’s pretty far off and there is quite possibly a bent valve or two. Once you get the new belt, tensioner…etc installed properly you can try to run the engine and see how it runs. You can also do a compression leakdown test to see if there’s leakage due to a bent valve. The other option would be to not redo the belt and instead pull the head off and have it inspected.
So apparently that’s the timing belt tensioner spring. Ugh, hoping it’s not as bad as you said Colin. Thanks for the help, I’ll dig in to it on Saturday and let you know what I find.
Yes, but “could” is the operative word here. Sometimes there’s damage, sometimes there isn’t, none of us can know for sure what happened to him until he actually checks to see what happened.
Thanks guys, I’ll let you guys know tomorrow. Gonna just go ahead and change the timing belt and reset the timing and hope for the best. I guess I’ll know once I start her up and do a compression test.
Also if by chance the valves did hit the pistons, besides replacing the valves wouldn’t the pistons have to be replaced at that point? I’m assuming the valve is the weaker of the two components so obviously it would bend, but wouldn’t there be some damage to the top of the piston.
Again, that’s tough to predict. A little cosmetic damage to a piston isn’t a big problem, so often all you’d need would be a new valve or multiple new valves. But depending on the situation there could be additional damage to the piston, cylinder walls or combustion chamber surface on the cylinder head.
So I was able to get everything apart and just waiting on the new parts to get here (was supposed to be delivered Saturday, thanks Fedex). Took the crank shaft pulley off to find this. So obviously it’s off by what seems a lot.
Nothing looks wrong to me. We’d need to see the cam pulleys to know how far off the timing is. And really you’d need to set the crank to TDC at the #1 cylinder and then compare to where the cams are at.
So when I’d try to set the cams at TDC the timing belt would jump. This is where I’m at with the cams. Also I noticed that when I turn the crank by hand there wasn’t any resistance, not sure that helps any. From what i understand, when you set the the cams to TDC or have the “UP” marks set, the marks on the crank should be lined up as well? When i had my friend help me do the headgasket I did notice that he had a hard time getting everything timed. "]
And when I’d set the crank to TDC the cams were at this point.
It’s best to turn everything at the crank, not the cams. At this point without the tensioner functioning properly it’s a waste of time to try and rotate the gears with the belt in place - as you noticed it’s just going to slip too easily. Resistance at the crank is dependent on where along the piston stroke you’re at. There’s also varying resistance at the cams depending on their orientation and how much pressure the valvesprings are exerting and on what part of the cam they are doing so.
From your last pic it definitely looks like the timing is way off - but you knew that, that’s why the engine shutdown. You need to remove the belt, set the cams and crank independently of each other, then reinstall the belt and fine tune the timing.
Yeah, you can, you do risk damage though. The safest technique would be to pull the valve cover and remove the cap caps so the cams are loose and the valves are allowed to push up all the way into the head. Then rotate the crank to #1 TDC and re-install the cam caps with the cams also at #1 TDC. Right now where the cams and crank are at you risk damage every time you rotate anything.
Well I was able to get the cam gear marks and the crank mark all lined up. Tensioned the belt, buttoned everything up. Went to turn her start her up and nothing. Turns over just won’t start. Anyone have any ideas? I’m stumped.
Don’t really feel like taking it to shop and having them put me over a barrel.
I’m not sure if it is the photographs but are the cam gears not set to “0” but advanced and/or retarded? I would set the cam gears straight up to 0, reset the cam timing and use a piston stop indicator on cylinder 1 to find TDC. As suggested above, if your engine timing is potentially way off I would take off the cam caps before setting the cams to correct timing, put the caps back on and retest. I would pull every spark plug and look down the bores with a flashlight and look for holes in pistons or pieces of valves because if the engine timing is good there are some serious issues to have compression numbers that low. I wish you all the best and hopefully the engine timing is still off causing the low numbers.
That’s what a friend suggested, was to double check the timing and try again. I’ll go back into it this weekend and let you guys know what I find. I’ll take the cam caps off and reset the timing hope fully it starts. I’ll let you guys know. Worst case I’ll have to pull the head, take the cams, valve springs, retainers and keepers out and put them in the new motor.
Well went back into it this weekend, and triple checked all the timing marks and everything. Tried starting her up and nothing, no compression on cylinders 1, 2, and 4. Cylinder 3 came read 100 lbs dry and 115 wet. I guess it’s safe to say the motors done.
Picking up a B20B this weekend, hopefully I can have it running in the next few weeks.
Well picked up the B20, went with the high compression one. Double checked it had the knock sensor on it and just bc I wanted make sure I pulled the head and saw PHK pistons :rockon:
Pulled the head cause I have to put all the parts from my B18 into the B20. Also when I pulled the head from the B18 I found this
I’m pretty sure it was possibly from the timing belt slipped. Took the head off and pulled the cams, valve springs, retainers and keepers, everything looked fine on the head none of the valves looked bent and the bottom end looked ok.
