Lost Compression today !

[dadysev]

Originally Posted by Crowz

I wouldn't if it didn't bend or damage the valve that's fixable without even removing the head.

Come to think of it. I would get a bit of lifter noise when i first start the truck for about 5 seconds and then it would go away?!?!

i'm wondering if the lifter is stuck or something, or when i did the rocker cover gasket recently a piece broke from the hardened rubber and lodged it self somewhere in there?

The condition of the head is not the greatest either. Dark and sludgey One of the worst i've ever seen.
Hmmm? I will know this weekend when I take off the cams and lifters.

[scourtaud23]

Lifter noise would be from extra play between the cam and the lifter/valve so it wouldn't be stuck open.

Rubber in the combustion chamber or close to it would burn quite quickly, it would be very unlucky if it managed to keep a valve open and survive.

At this point, take the head out and at the very least clean it, you will necessarily find something wrong.

[dadysev]

So tomorrow i'm dropping in a scope to look in the cylinder. Have a really good one!
I took off the exhaust cam today to look for broken valve springs, etc. I want to try pressurize the cylinder with out the cams on it just to determine if its a lifter or not. The rocker area looks disgusting!

i forgot to mention, when i got the truck i found almost 11 litres of oil in it! that was about 3000 miles ago. i can tell who ever had this before did not do regular oil changes, and i'm guessing they used regular gas also.

I bought it cheap so i can't really complain about the work ahead to be fair.

The question i have is, can i lifter extend and stick keeping a valve slightly open when it should be closed? not enough to touch the piston but just enough to cause 40 pounds compression?

[Crowz]

https://www.youtube.com/watch?v=_Vo4fm0JDPY

[dadysev]

Yeah. Seen that video and tried that. Didn’t make a difference.

[dadysev]

Originally Posted by Crowz

https://www.youtube.com/watch?v=_Vo4fm0JDPY

Also did the leak down and proved the exhausts valves. Not the rings.

[Crowz]

Lifters don't extend past the resting point. So I cant see that being the problem.

[andrewwynn]

Originally Posted by dadysev;

Come to think of it. I would get a bit of lifter noise when i first start the truck for about 5 seconds and then it would go away?!?!



i'm wondering if the lifter is stuck or something, or when i did the rocker cover gasket recently a piece broke from the hardened rubber and lodged it self somewhere in there?

Totally normal to hear lifters until the oil pressure builds. (at least in both of my x5s). I count the seconds to determine if it's time to aid oil.

"Full " on the dipstick is the middle not the top FYI at least that's what I've read.

Back to the topic: severe loss of compression in one cylinder from exhaust valve not seating.

If you already have the valve covers off, actually doesn't even matter: take the fuel pump fuse out so the car can't "diesel" and poke an inspection camera in the cylinder and look.

If the VC are off, use a digital calipers to measure the change in height of all the valves. You may discover a critical difference, also look at the springs, a broken spring will reduce the close force and will allow all sorts of build up on the valve and valve seat.

There is a chance the valve or valve seat are actually damaged.

[dadysev]

Burnt valve!!

[Crowz]

Well cheap fix at least.