1FZ-FE compression and valve leak tests... Cylinder head rebuild impending (1 Viewer)

[Fearnofish!]

Hello All,
Short story: ~200,000miles. 1996 1fzfe. drinking oil-qt/250 miles. replaced PCV valve and grommet. Can smell burning oil at start and in exhaust. goes away while driving. Engine still feels strong and pulls fairly hard but definitely sounds different than it used to sort of "valve slappy" or "sticky". A few months ago added a can of Restore for 6cyl engines. Had it tested at a shop that rebuilds engines and has all the tools on had to handle high perforce jobs so I know their analysis is accurate.

Looks like the following:
1. the lower end perhaps has had a ring job previously or been rebuild because the compression is STRONG.
2. the leaky valves suggest the head hasn't been rebuilt and is on its way out. Impending head rebuild.

So naturally im looking for a head to rebuild and any additional conclusions/info that the great and wise to-Yoda folks have.

 

[450LX]

What oil do you use? These things love to drink synthetic 5w30 like Colorado Kool Aid! Try some good ol 15w40 Rotella and see what your consumption is.

 

[Fearnofish!]

I haven't used synthetic. high mileage castrol 10w40. I've read the posts here about changing to synthetic and having all sorts of leaks spring up.

 

[Fearnofish!]

Hey all, those compression #s seem high to me. Any thoughts?

 

[mingles]

According to the FSM (attached) the compression numbers should be greater than 171 psi and no greater variance between cylinders than 14 psi. Your compression numbers pass under that test. I would think the actual psi# is largely dependent on how fast the engine turns over during the test.

With respect to the oil consumption, my '97 LX was burning 1 qt of 5W30 every 300-500 miles. I switched to Rotella 15W40 and now burn about 1 qt every 1000 miles. That was 2 years and 50K miles ago. Eventually I will need to do a top end rebuild to address worn valve guide seals but in the meantime, oil is cheap and the truck runs great. FWIW - my compression numbers @ 300K are all between 178 psi and 187 psi.

 

[Fearnofish!]

Great feed back. Thanks.

 

[Malleus]

With that much oil use, I have to ask how wet the bottom of the engine is. The pan arch seal notoriously leaks.

 

[Fearnofish!]

actually no leaks! leaky power steering pump reservoir but thats it.