The Resurrection of (10/1998 to 01/2021, 11/21- 11/25) Elizabeth 1999 V70T5M56 Cylinder Head Job Topic is solved

[erikv11]

What Neil said - the compression test is just for checking cylinder health. Won't give you any clues on the valve stem seals but sounds like you have a handle on them already. Will only tell you about valves if one is really bad - you'd know already.

[scot850]

Yep! I'd say they are well past due! LoL!

[misha]

Thanks guys...i'm gathering all info i can get.
I trust my mechanic....but i would like to be prepared for this...for myself.

So....compression on warm engine first.

Opinions are divided on this....somebody says on cold engine....somebody on warm engine.

[scot850]

Warmer engine is better but you can do both and compare. It may give you a read on the piston ring condition or bore wear. Argument for not doing when engine is cold is engine is harder to turn over and may not give consistent results

Neil

[foggydogg]

There is a lot of carbon build up in that head. I am wondering if the issues we are having with valves burning is due to stem seals leaking into the cylinders and burning causing hot spots taking the valves out?

I think this exactly what happened to me. I didn’t burn a lot with Castrol High Mileage Synthetic but the Pennzoil synthetic burned nasty.

I started smoking on overrun at about 180k miles, 80k ago.

I got lucky in the valve drop, 5 miles from home on a 500 mile round trip, didn’t even need a tow.

I think the other part of the 'luck' equation was the errant piece escaped, instead of dancing around for a while on top of the piston. We lost a big chunk of an intake valve on the racecar once, it imbedded itself on top of the piston and stayed there for the rest of the race. We weren't running all that well that day, so the poor thing didn't even slow down much. Quite a scramble at the shop that night to swap motors and be ready for the afternoon race the next day. I was fresh out of the Navy, so I was still used to operating on no sleep.
Ah, those were the days. Sure glad I don't do that anymore.

[abscate]

Ah, Navy. I knew I liked you for a good reason?

What do the Air Force, Army, and Navy all have in common?

They all want to be in the Navy.

[bmdubya1198]

Warmer engine is better but you can do both and compare. It may give you a read on the piston ring condition or bore wear. Argument for not doing when engine is cold is engine is harder to turn over and may not give consistent results

Neil

That and all tolerances are closer to proper spec when warm, so you'll have more accurate numbers. There's no real reason to do a compression test on a cold engine unless you're trying to diagnose a cold running issue.

[abscate]

Got my valves in from FCP,today, waiting on the valve stem seal kit from Tasca to drop,off at machine shop

Reflections....on my engine there are none of those semi circle divots that look like valve hits on any of my piston tops

I also got the front end up supported up in preparation for the steering rack replacement, on order.

The four large subframe bolts, 18mm hex heads, cracked easily with the 2 foot breaker bar and a 1/2 inch drive impact socket

[foggydogg]

Ah, Navy. I knew I liked you for a good reason?

What do the Air Force, Army, and Navy all have in common?

They all want to be in the Navy.

When some of my Shipmates felt like getting frisky at the bar, they would remind any Marine in earshot that we were happy to give them a ride - and that at the top of their paycheck, it said 'United States Navy'.
Submariners never consider themselves part of the Navy, mostly because wherever we went, we were utterly alone and on our own.
Plus, some of them fellers were slightly off-center.
I, however, am nearly normal.
Looks like your machine shop/part delivery pause was timed right for weather.

[abscate]

Submariners are their own breed, indeed.

There is another joke about Marines and sheep being too obvious which will definitely start a bar fight