99 Volvo 3l, Bad compression, leak down tests shows valve blow-by, pictures inside

[northernterritory]

My manifold had a crack in it causing water intrusion. The first compression test shows erroneous results; some cylinders with no compression. The second compression tests showed cylinder one 80/90, cylinder two 140/150, cylinder three 95/100, and cylinder four 90/159. That?s dry/wet numbers. I went ahead and did a leak down test. All cylinders had significant air blow-by past the valves. There was so much valve blow-by on cylinder four, I don?t see how it created so much compression wet.

I removed the head. I have attached pictures. Piston three looks like, to me, to have detonation signs. Would you look at the pictures please and give me an assessment? What should be my next move? Note, that the whiteness on the other pistons is from the flash.

 

[northernterritory]

No Title

More photos...

 

[Scott Danforth]

Piscs show water intrusion. Head needs to be gone thru, the rusty valves should be at least dressed, i would replace

 

[northernterritory]

Piscs show water intrusion. Head needs to be gone thru, the rusty valves should be at least dressed, i would replace

Do you have a link to what I need to do? I am a little clueless when it comes to working on heads.

 

[Scott Danforth]

you take the head to a machine shop. when they are done, you pay them $150

 

[Bondo]

Ayuh,..... I see a rebuildable core motor,.... Not a fixable runner,....

 

[northernterritory]

Is there anywhere I can buy a remanufactured head for around the price of having a machine shop redo mine?

What do you think is going on with cylinder three's piston?

Is it economically feasible to get the head redone, a new head gasket, put the head back on, do a compression test, and then buy a remanufactured short-block if the numbers aren't there?

 

[Lou C]

It's do-able but then you will be doing the same work twice. Risky but I can understand the desire to try it.

 

[Bondo]

What do you think is going on with cylinder three's piston?

Ayuh,.... #3 is why it needs to be rebuilt,.... Ya don't do just 1 cylinder, ya do 'em All,....

Probably caused by a lean condition,....
So fix yer fuel system before ya burn up another motor,....

 

[northernterritory]

Ayuh,.... #3 is why it needs to be rebuilt,.... Ya don't do just 1 cylinder, ya do 'em All,....

Probably caused by a lean condition,....
So fix yer fuel system before ya burn up another motor,....

Is there any scenario were the engine is not ruined from the detonation on the cylinder three piston? It seems like there is minimum damage to the piston compared to a lot of other detonation damaged pistons I have seen. Can a blown head gasket create a lean environment, and thus the detonation?

Is there anywhere I can buy a remanufactured head for around the price of having a machine shop redo mine?

Is it economically feasible to get the head redone, a new head gasket, put the head back on, do a compression test, and then buy a remanufactured short-block if the numbers aren't there?

 

[Bondo]

Is it economically feasible to get the head redone, a new head gasket, put the head back on, do a compression test, and then buy a remanufactured short-block if the numbers aren't there?

Ayuh,.... Logical at this point is to buy a reman Long Block motor,....







'n fix the fuel system,...

 

[northernterritory]

you take the head to a machine shop. when they are done, you pay them $150

Scott, if I do take the head to a machine shop, what do I tell them to do with the head? I don't want to say a blanket statement like "make it like new again," because I am afraid that will be like a blank check.

 

[Scott Danforth]

you are obviously new to working on motors

any good machine shop would pressure check, inspect the guides, inspect the valves, and only perform the work needed. they will also give you a quote up front.

however I would post a better picture of cylinder #3. you may be better off with a replacement motor