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2G Did I get lucky? Broken timing belt.

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Bluedragondsm

20+ Year Contributor
350
2
Nov 14, 2002
Edmonton, AB_Canada
Timing belt broke a few years ago and while getting ready to pull and replace the engine i decided to pull the valve cover and i noticed that none of the valve lashes were loose and i couldn't move any of them by hand as you sometimes can when a valve is bent. They were all snug against the cam.

The engine spins freely and there's no noise, i looked in the spark plug hole with a light and didn't see any obvious marks in the piston.

I'm tempted to just put a new timing belt kit on it and try it since i have one here.

My only big worry is the kit i have i was going to use for the new engine since it's only coming with a belt and not the pulleys/tensioner etc.

What do you guys think.
 
The crank freely spins does not mean you have no bent valves. If valves are bent just slightly then it spins.
If I were you, I would do a compression and/or a leak down test first. You can't be so sure until do the test.
 
The only time I "got lucky" is when I jumped a tooth or 2 without bending a valve, if the belt broke under a pull or driving conditions I can almost guarantee that you have some bent valves, as suggested do a compression/leakdown test.
 
The only time I "got lucky" is when I jumped a tooth or 2 without bending a valve, if the belt broke under a pull or driving conditions I can almost guarantee that you have some bent valves, as suggested do a compression/leakdown test.

I'm buying a freshly rebuilt engine from a fellow dsm builder so I'll probably just wait and tear down the engine when it's out of the car.

I thought maybe i could salvage this engine but from the sound of it i can't so i might as well just pull it for the rebuilt one since the rebuilt one has all new seals and gaskets and internals anyway. Considering its almost the same amount of work pulling the engine as doing a timing belt it's not worth wasting time on a engine that needs new seals and gaskets in multiple places on top of a possible head rebuild.
 
My timing jumped when I turned my car off one time (eclipse). Prob jumped a tooth or two, but I was able to retime it and fix the issue. I believe it was a bad hydraulic tensioner. I definitely got lucky on that one. But car ran perfect after I fixed it. Running mid 12’s on small 16g . Worth checking the engine out more I would say. You could be lucky.
 
I've never actually done a leakdown test, how would i make sure the valves are fully closed (assuming they aren't bent)?

Would i just remove the cam shafts before doing the test? The car currently has no starter or timing belt on it.
 
I got my borescope as a 5 year gift from work, but it's a decent one. Whistler brand, Walmart has them for around 70-80 bux, or you can get one that hooks directly do your phone, they work pretty decent and are cheap at >$20.

WHISTLER

ANDROID IPHONE

I have one if each and both do the job well. But as I and @pauleyman have said, do a leakdown test. Pulling the cams ensures you won't cause any (further) valve damage, and it only takes about 15-20min to complete the whole test. It will tell you worlds more info with minimal effort.
 
Did the timing belt actually break or did it skip timing?
You might be lucky if you just skipped timing.
Usually not a big issue to get the valves replace and would be much easier than replacing the whole engine in my opinion.
As mentioned it's fairly easy to pop the valve cover and remove the cams, this would allow all the valves to close at which point you can pressurize the cylinders and see how fast they bleed down.
 
Timing belt broke a few years ago and while getting ready to pull and replace the engine i decided to pull the valve cover and i noticed that none of the valve lashes were loose and i couldn't move any of them by hand as you sometimes can when a valve is bent. They were all snug against the cam.

The engine spins freely and there's no noise, i looked in the spark plug hole with a light and didn't see any obvious marks in the piston.

I'm tempted to just put a new timing belt kit on it and try it since i have one here.

My only big worry is the kit i have i was going to use for the new engine since it's only coming with a belt and not the pulleys/tensioner etc.

What do you guys think.
Timing belt broke a few years ago and while getting ready to pull and replace the engine i decided to pull the valve cover and i noticed that none of the valve lashes were loose and i couldn't move any of them by hand as you sometimes can when a valve is bent. They were all snug against the cam.

The engine spins freely and there's no noise, i looked in the spark plug hole with a light and didn't see any obvious marks in the piston.

I'm tempted to just put a new timing belt kit on it and try it since i have one here.

My only big worry is the kit i have i was going to use for the new engine since it's only coming with a belt and not the pulleys/tensioner etc.

What do you guys think.
Hi! Hope you really get good luck with the engine, in my experience... if the timing belt is completly broken there listen be some (at least) bent valve... hope there is only one or two.. first do the leak down test.... If not, put the new timing belt, try to turn the engine then by hand and try to feel if the resistance to turn is the same in all cycles of the movement (compression stroke) if not take the cylinder head off... Good luck!!!
 
Did the timing belt actually break or did it skip timing?
You might be lucky if you just skipped timing.
Usually not a big issue to get the valves replace and would be much easier than replacing the whole engine in my opinion.
As mentioned it's fairly easy to pop the valve cover and remove the cams, this would allow all the valves to close at which point you can pressurize the cylinders and see how fast they bleed down.
I'm not 100% sure, the crank spins and the cams don't, i cut the old belt and wasn't able to pull it up. My theory is one of the pulleys striped the belt.

I got into the Bay and honestly I'm just going to replace it. The oil pan is dented, the entire bottom end of the engine is caked in oil so there's a serious leak somewhere. When i drained the coolant there was some rainbow in it so there might be a minor head gasket problem. I also removed the heat shield to get better access to the belts and an exhaust bolt literally broke in half with no effort.

I have to cut out some rust in the strut tower and w weld in New metal and with how cheap this guy is selling a never ran, fully rebuilt motor it would be the same price as a valve job plus i get a clutch and new timing belt included. Just seems easier to start new at this point.
 
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