Only 1 lifter bore tolerance is out.
Thread Starter
Teching In
Joined: Nov 2023
Posts: 6
Likes: 1
Only 1 lifter bore tolerance is out. L86 rebuild
Entry way (the top portion about 1/4" down) of one lifter bore is out of tolerance.004 only one is like this. Will this cause oil issues or any others?
Thanks in advance
Entry way (the top portion about 1/4" down) of one lifter bore is out of tolerance.004 only one is like this. Will this cause oil issues or any others?
Thanks in advance
TECH Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
If it ran OK that way before overhaul, it would run OK afterwards. Unless of course that looser top of the hole bled off too much oil pressure. Did it???
Think about it. Is the rest of the hole in spec? Is there a chance of oil pressure bleed off?
Think about it. Is the rest of the hole in spec? Is there a chance of oil pressure bleed off?
Thread Starter
Teching In
Joined: Nov 2023
Posts: 6
Likes: 1
The bore needs to be honed. Lifter bore clearance must be maintained over the entire bore. If it’s tight…even in one spot…it will cause the lifter to try to stick in the bore, and chew itself (or the block) up. If it’s loose you will have oil pressure problems. Fix it right and avoid the headache down the road. If the bore can’t be honed, it can be bored and a lifter bore sleeve installed, and it in turn gets honed to size. Been there, done that, and got the t-shirt.
Most machine shops are going to be particular to their favorite brands and install methods so to guarantee a successful outcome. Having said that there really nothing to it, just a sleeve of metal, usually aluminum or bronze. Very similar to a cylinder sleeve install, just much smaller, and has an oil hole in the center.
I like CHE bronze bushings, but as bthomas said, it will be up to the shop. Trust them. Typically not a very expensive repair either. Doing one is easy peasy. Doing all 16 is completely different and requires a CNC program to get them all correct.
