Rotating crank shaft - loud pop from cam area. Anything wrong here?
Aug 19, 2010, 02:43 AM
#1
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Rotating crank shaft - loud pop from cam area. Anything wrong here?
Hey guys. Tried searching but didnt find any info.
I am in the process of changing cams in my Evo 9.
Broke the timing belt tensioner tool of course and doing everything the long way. While i am rotating the crank shaft to set everything to TDC, the motor turnes over and there is a loud pop coming from the area under the valve cover (somewhere where cams are). This is all before the install of the cams. Spark plugs are still in. I did loosened intake cam bolts. I did try to slide int cam gear off while screwing the tensioner tool in and it didnt come out all the way. Gears were zip tied.
Could I damage something while rotating the crank shaft? Talking about bent valves or something? Also can I just leave the broken timing belt tensioner tool piece in that bracket or does it have to be taken out?
Any thoughts guys?
Thanks
I am in the process of changing cams in my Evo 9.
Broke the timing belt tensioner tool of course and doing everything the long way. While i am rotating the crank shaft to set everything to TDC, the motor turnes over and there is a loud pop coming from the area under the valve cover (somewhere where cams are). This is all before the install of the cams. Spark plugs are still in. I did loosened intake cam bolts. I did try to slide int cam gear off while screwing the tensioner tool in and it didnt come out all the way. Gears were zip tied.
Could I damage something while rotating the crank shaft? Talking about bent valves or something? Also can I just leave the broken timing belt tensioner tool piece in that bracket or does it have to be taken out?
Any thoughts guys?
Thanks
Aug 19, 2010, 10:47 AM
#5
Well if you were free rotating the crank with a tool while having the cam gears stationary installed in the head then it is possible you did some damage. If everything was hooked up in time then being driven together by the timing belt then you are probably fine.
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Aug 19, 2010, 02:06 PM
#8
how hard is it to take off the plastic covers to make sure nothing is wrong?
that way you can be 100% sure that the crank and oil pump is aligned correctly...
if could have broken the tensioner tool into 2 pieces, not just 1. then you'll start your car and blow up your engine.... >.<
better to be safe for the sake of 1hrs extra work
that way you can be 100% sure that the crank and oil pump is aligned correctly...
if could have broken the tensioner tool into 2 pieces, not just 1. then you'll start your car and blow up your engine.... >.<
better to be safe for the sake of 1hrs extra work
Aug 19, 2010, 03:06 PM
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1. Engine should have been at TDC before starting disassembly, this may just be my OCD but that's how it should be done.
2. By "loosened intake cam bolts" do you mean the cam cap bolts or the cam gear bolt? If you loosened all of the cam cap bolts then the "pop" could have been the spring tension pushing the cam caps out and hitting the bolts that are loose but still threaded in partially.
3. Cam gear attempted to be removed then rotate the engine? was the dowel pin still turning the cam?
4. Like a few people have already stated I would go ahead and take the extra time to remove all the covers and double check timing and then carefully install the cams correctly. Carefully check the cam caps and journals for any damage from rotating the motor over with the cam caps loose. When all is said and done do a compression check or leak down check to make sure nothing was damaged.
Josh
Aug 19, 2010, 04:28 PM
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1. Engine should have been at TDC before starting disassembly, this may just be my OCD but that's how it should be done.
2. By "loosened intake cam bolts" do you mean the cam cap bolts or the cam gear bolt? If you loosened all of the cam cap bolts then the "pop" could have been the spring tension pushing the cam caps out and hitting the bolts that are loose but still threaded in partially.
3. Cam gear attempted to be removed then rotate the engine? was the dowel pin still turning the cam?
4. Like a few people have already stated I would go ahead and take the extra time to remove all the covers and double check timing and then carefully install the cams correctly. Carefully check the cam caps and journals for any damage from rotating the motor over with the cam caps loose. When all is said and done do a compression check or leak down check to make sure nothing was damaged.
Josh
2. By "loosened intake cam bolts" do you mean the cam cap bolts or the cam gear bolt? If you loosened all of the cam cap bolts then the "pop" could have been the spring tension pushing the cam caps out and hitting the bolts that are loose but still threaded in partially.
3. Cam gear attempted to be removed then rotate the engine? was the dowel pin still turning the cam?
4. Like a few people have already stated I would go ahead and take the extra time to remove all the covers and double check timing and then carefully install the cams correctly. Carefully check the cam caps and journals for any damage from rotating the motor over with the cam caps loose. When all is said and done do a compression check or leak down check to make sure nothing was damaged.
Josh
The broken tool piece is sticking out of that housing thats under the lower timing cover. It is not in contact with anything and the is no way to take it out. Its in there tight. Ive been trying for a while. I am thinking just to leave it there unless someone will convince me otherwise. I did some research and many people leave them in. It just looks pretty tough to remove that side mount piece where this tool is threaded. Not sure how to do that.
The cam gear bolts were loosened not, cams were untouched.
Both cams were always turning when i rotated the engine.
I took the plugs out and the sound was almost gone.
But now as I recall it did sound something like a spring popping sound.
Btw here is a pic of broken piece
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Last edited by tboboy; Aug 19, 2010 at 04:47 PM.
Aug 19, 2010, 08:56 PM
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No worries
Aug 19, 2010, 10:23 PM
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Just wanted to clear up one more thing.
When there is no oil pressure inside Mivec cam gear, does it make the gear rotate a bit back and forward without rotating the cam? (thats of course with the timing belt off)