Need Help! Timing Belt Issue - Engine won't turn over
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Need Help! Timing Belt Issue - Engine won't turn over
Hey everybody, I'm in the process of replacing my timing belt and have run into a weird issue. I've searched on Google and the forum and I can't seem to find exactly what my issue is.
Here's the problem: I marked the old belt at TDC not 50deg ATDC as seen on some of the guides (may be part of my issue). I removed the old belt, the cams did not spin that I saw. I put my new Gates belt on and the marks all matched up with the cam gears and crank gear. But when I try to turn the engine over by hand it stops at about 60 to 70 deg ATDC and sound like valves are hitting a piston. I don't know how it could have got out of time.
What is the correct way to retime the engine now if the cam or crank gears have moved from when I took the belt off? I've tried to turn both cams and crank to TDC, put the belt back on and still have the same issue. I just have a really hard time believing the engine could be so out of time enough to be contacting valves with the piston.
Any help would be greatly appreciated. I can post pictures if that will help.
Thank you!
Here's the problem: I marked the old belt at TDC not 50deg ATDC as seen on some of the guides (may be part of my issue). I removed the old belt, the cams did not spin that I saw. I put my new Gates belt on and the marks all matched up with the cam gears and crank gear. But when I try to turn the engine over by hand it stops at about 60 to 70 deg ATDC and sound like valves are hitting a piston. I don't know how it could have got out of time.
What is the correct way to retime the engine now if the cam or crank gears have moved from when I took the belt off? I've tried to turn both cams and crank to TDC, put the belt back on and still have the same issue. I just have a really hard time believing the engine could be so out of time enough to be contacting valves with the piston.
Any help would be greatly appreciated. I can post pictures if that will help.
Thank you!
#3
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There are, and I thought I matched them up to the new belt before installing it. After reading some more online, I think I bent a valve or two when I bumped the starter if it was out of time.
I'm in the process of pulling the driver side head. At this point that is the only thing that makes sense. I have the intake off and will be pulling the head shortly.
If anyone has any other advice before I pull the head, that would be great, but I think that is my issue.
I'm in the process of pulling the driver side head. At this point that is the only thing that makes sense. I have the intake off and will be pulling the head shortly.
If anyone has any other advice before I pull the head, that would be great, but I think that is my issue.
#4
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So you turned the motor over with the starter ???!!!??? Ouch
This is the issue with aftermarket timing belts, some come with perfect markings, some with slightly ambiguous markings, and some come with no markings at all. Gates makes great belts but IIRC the marks on a Gates belt can be a bit confusing. But if you already have a bent valve and a head almost off no belt related discussion is going to help...
This is the issue with aftermarket timing belts, some come with perfect markings, some with slightly ambiguous markings, and some come with no markings at all. Gates makes great belts but IIRC the marks on a Gates belt can be a bit confusing. But if you already have a bent valve and a head almost off no belt related discussion is going to help...
#5
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Most important thing to remember is - Do not rotate the crankshaft counter-clockwise!
The crankshaft and the two camshafts must align properly for the engine to work. You can start with verifying if your current installation is "close" to where things should be by counting "teeth" on the 3 gears. Refer to the sketches below, first count how many teeth you have rotated the crankshaft from the TDC mark. Second, count and confirm if each of the two camshaft pulleys had rotated from their respective timing mark by the same number of teeth. If not, you will have to remove the timing belt to adjust.
Take you time and always rotate clockwise.
The crankshaft and the two camshafts must align properly for the engine to work. You can start with verifying if your current installation is "close" to where things should be by counting "teeth" on the 3 gears. Refer to the sketches below, first count how many teeth you have rotated the crankshaft from the TDC mark. Second, count and confirm if each of the two camshaft pulleys had rotated from their respective timing mark by the same number of teeth. If not, you will have to remove the timing belt to adjust.
Take you time and always rotate clockwise.
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Thank you guys for the responses. I really do appreciate it.
UPDATE: I pulled the driver valve cover and it does appear the exhaust valves on cylinder 1 and 7 are slightly bent as they are not returning to full close when I turn just that cam (timing belt off)
Looks like it's time to pull the head and get some new valves installed by a machine shop.
I'm besides myself right now and still confused as to how this happened.
UPDATE: I pulled the driver valve cover and it does appear the exhaust valves on cylinder 1 and 7 are slightly bent as they are not returning to full close when I turn just that cam (timing belt off)
Looks like it's time to pull the head and get some new valves installed by a machine shop.
I'm besides myself right now and still confused as to how this happened.
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