low compression in Cyl#2 after head rebuild, new lifters to blame???

importvic · Jan 9, 2003

I know this is not a DSM, but this is a topic related to the updated lifters sold by Dave Mckinney, I hope my DSM brotherin can help me out because I don't know who else to ask.

I just had the heads rebuilt on my Montero(3.5 DOHC 24V 6G74) with the new style lifters, & an OEM head rebuild kit. the mechanic is telling me today that there is now low compression in Cyl #2 & that the new lifters could be to blame. since I supplied the lifters I think he's trying to find a way he could blame his possible F-up on me.
I was puzzled as how a lifter could cause this, & he said it something to do with the lifter not being properly compressed, or possibly a defective lifter, & this will cause the valves not to fully close.
I'm thinking to myself, "hmm, high compression engine = very little, to no room at TDC" if the valve isn't fuly closing its probibly bent by now, no?"

my question:
is my mechanic full of S?
if so what do you think might have caused this low comp?
any help would be greatly appreciated. thanks! :rudolph:

Redsand187 · Jan 10, 2003

Have him do a leak down and prove that it is the valve that is leaking. I would doubt that the lifter is to blame.

funkeymonkey202 · Jan 11, 2003

i agree with redsand187

have him prove it to you im almost thinkin he just wants something else to blame it on BESIDES HIMSELF

Taboo · Jan 11, 2003

importvic said:
my question:
is my mechanic full of S?

Nope, the mechanic may be actually right. Happened to me.

importvic said:
I'm thinking to myself, "hmm, high compression engine = very little, to no room at TDC" if the valve isn't fuly closing its probibly bent by now, no?"

You may be actually right as well. The only way to find out if it's the valve or the lifter is removing the rocker (which should cause the valve stay 100% closed at all times) and then running a leak-down and/or compression test. If the compression stays low, it's the (bent) valve, if the compression goes up to specs, it's most likely the lifter. Good luck.

importvic · Jan 13, 2003

well got the truch back. sounds stronger, & quieter. mechanic says it was the uncompressed lifter, & he fixed the problem. I want to get a compression test done, just to be safe, but it'll be expensive because the 3-piece intake plenum sits right over the sparg plug wells, which requires alot of hours of labor. the only problem I'm having is the idle goes very low sometimes, & the gas pedal is sticky in the morning.

low compression in Cyl#2 after head rebuild, new lifters to blame???

importvic

Redsand187

funkeymonkey202

Taboo

importvic

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