Top-end engine ticking after track session
Thread Starter
Joined: Jan 2012
Posts: 690
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From: SF Bay Area
Finally got a chance to dive back into this project today. I removed the valve cover and didn't find any smoking guns, at least not right away. Upon pulling the spark plugs it was evident that #2 and #4 are oil-fouled. These were fresh plugs installed approximately 300 miles ago.
I'm planning to get a borescope to check things out (I'd like to have one anyway) but I'll be starting the search for a replacement motor in any case...
I'm planning to get a borescope to check things out (I'd like to have one anyway) but I'll be starting the search for a replacement motor in any case...
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Joined: Jul 2002
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From: Long Island, New York
A spun bearing will knock a few times on cold start, disappear completely, then return as the engine warms.
Your noise frequency is too slow to be Tct, it sounds like a piston skirt/cylinder issue.
Your noise frequency is too slow to be Tct, it sounds like a piston skirt/cylinder issue.
Thread Starter
Joined: Jan 2012
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From: SF Bay Area
In any case, I think it's prudent to start looking for a new motor... :\
Joined: Sep 2008
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Hi Bill, I tend to agree. I've thought about it quite a bit and from all the evidence I'm guessing it's "piston slap". Seems like the bore(s) rapidly wore down and created excessive clearance between the piston and bore. That's my current hypothesis anyway...
In any case, I think it's prudent to start looking for a new motor... :\
In any case, I think it's prudent to start looking for a new motor... :\
1.) you haven't bore scoped, which would confirm your thoughts
2.) If you are correct compression should be effected and/or you would be burning oil.
3.) Unless you are going to try for an OEM rebuild what is to gain by not running the motor till it blows up? Even then say you spin a bearing, just sleeve and stroker build it.
Thread Starter
Joined: Jan 2012
Posts: 690
Likes: 12
From: SF Bay Area
IDK if I would jump to a new motor just yet.
1.) you haven't bore scoped, which would confirm your thoughts
2.) If you are correct compression should be effected and/or you would be burning oil.
3.) Unless you are going to try for an OEM rebuild what is to gain by not running the motor till it blows up? Even then say you spin a bearing, just sleeve and stroker build it.
1.) you haven't bore scoped, which would confirm your thoughts
2.) If you are correct compression should be effected and/or you would be burning oil.
3.) Unless you are going to try for an OEM rebuild what is to gain by not running the motor till it blows up? Even then say you spin a bearing, just sleeve and stroker build it.
Registered User
Joined: May 2014
Posts: 594
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From: Pittsburgh
I once had a valvecover that was bead blasted, for peace of mind I decided to wash it out before installation and I was shocked how much grit came out of it. Plus all threaded holes were jam packed which killed some of the threads and I had to clean them out with a tap. Never getting that done again.
Thanks.
Thread Starter
Joined: Jan 2012
Posts: 690
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From: SF Bay Area
Replacement engine is sourced and I'm picking it up tomorrow. 
Hoping I can get away with dropping the subframe/engine/trans as a unit so I don't have to dick around dropping the tranny in my garage, without a lift. Also planning to install a lightweight flywheel and replacing hard-to-reach components while everything's out.
Hoping I can get away with dropping the subframe/engine/trans as a unit so I don't have to dick around dropping the tranny in my garage, without a lift. Also planning to install a lightweight flywheel and replacing hard-to-reach components while everything's out.