Jump to content
Volvospeed Forums

My Pistons Are Happy


Speedbump

Recommended Posts

:) :) :) :) :) :)

They did it 4 teh LOLz

IMG_0079.jpg

IMG_0078.jpg

IMG_0082.jpg

( PREVIOUS COMPRESSION SAID 2 cyls no compression at all , 1 cyl 45psi , 2 cyls good )

I guess it's possible cyl 1 is in "up" stroke, and cyl 5 is in "down" stroke.

But for some reason this doesn't look right. Have I got a bent/broken piston rod as well?

I'll have to pull the wheel off to spin the crank. My point is... is it necessary?

FROM TOP OF CYLINDAR

Cyl one 3.25"

Cyl two 1.75"

Cyl three UP

Cyl four 1.5"

Cyl five 3.5"

Link to comment
Share on other sites

Not sure what you're asking here. The pistons and liners appear to be ok. If you have low or no compression, maybe take a look at the head. Do you have valves with holes in them? Since that is a N/A motor, I can't imagine you breaking a rod unless you had a major seizure or a hydro lock event. If you broke a rod, it would surely be through the block. A piston comes to the top every 72 degrees so your numbers don't reveal much.

Link to comment
Share on other sites

Unless you have very accurate measuring tools and are very precious in your measurements you can not tell with the pistons and rods in the block. I was working on a M3 and everything looked ok with the head off. Once the piston and rods were out it was obvious that the #1 rod was bent. Not much more work to pull the pan and take the piston & rods out. Good Luck.

AG

Link to comment
Share on other sites

Thanks guys. No it wasn't intended to be a precise measurement. I just didn't expect two cylinders so far down. Looked weird so wanted to ask.

My tensioner quit and hammered the valves.

If piston damage is not typical, then I'll proceed as planned and throw a bone yard cylinder head on it.

Link to comment
Share on other sites

With the scenario just pull the cams, put the plugs back in and fill each combustion chamber with oil. If it leaks out the ports you have bent valves.

Link to comment
Share on other sites

Handy trick.

I'm pretty confident these valves are bent.

I can still flip the head over with scrap plugs in it and dump some sauce in it and see it the valve seals leak.

Tomorrow in the backyard so I won't have a mess to clean up in the garage..

That sounds good for the environment :blink:

Link to comment
Share on other sites

Unless you have very accurate measuring tools and are very precious in your measurements you can not tell with the pistons and rods in the block. I was working on a M3 and everything looked ok with the head off. Once the piston and rods were out it was obvious that the #1 rod was bent. Not much more work to pull the pan and take the piston & rods out. Good Luck.

AG

Even if a rod was bent, it wouldn't lead to zero compression. I agree however that pulling the pan is easy and a good idea if in doubt about the rod condition, or to install new rod bearings.

Link to comment
Share on other sites

Even if a rod was bent, it wouldn't lead to zero compression. I agree however that pulling the pan is easy and a good idea if in doubt about the rod condition, or to install new rod bearings.

I went and looked at the head today and under closer examination I can see cylindar 3 and cylindar 5 both have an intake valves that are not seating. I'll do the head and timing kit and hopefully that's as far as the damage goes .

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...