Old block, bad rings?

[Jordan325iC]

I'm looking at a S-ETA block for my stoker project, but the problem is it's been sitting for 1.5+ years. I am worried to piston rings might have gone bad while it sat. Supposedly it was in good condition before it began its sitting.

Opinions?

Any way to check the piston rings w/o the head on?

[JasonC]

Wouldn't you freshen the motor up anyway, before you stuck it in the car?

[PiercedE30]

Put some Kroil on the cylinder walls/rings and let it sit for a few days before turning the crank over. Should help free up some stuff.

[StereoInstaller1]

Other than checking the bore and checking the ring gap, there is no real way.

2 things that might make it more obvious what you really have there is to check the walls of the cylinders for remaining "crosshatch" and look for "ring ridge".

[Jordan325iC]

Wouldn't you freshen the motor up anyway, before you stuck it in the car?

I fear that I would screw up a bottom end rebuild since I've never done one before.

Other than checking the bore and checking the ring gap, there is no real way.

2 things that might make it more obvious what you really have there is to check the walls of the cylinders for remaining "crosshatch" and look for "ring ridge".

You can see the crosshatch on the cylinder walls still. What is "ring ridge"?

[jlevie]

"ring ridge" is a ring at the top of the cylinder bore that resulted from wear of the bore by the rings. If you can still see the cross hatch on the cylinder bores, there can't be enough wear to form a ring ridge.

[Jordan325iC]

"ring ridge" is a ring at the top of the cylinder bore that resulted from wear of the bore by the rings. If you can still see the cross hatch on the cylinder bores, there can't be enough wear to form a ring ridge.

So if you can still see the crosshatch, the piston rings are still good?

As I said before, presumably they were good before the block was taken out. I am worried that they have went bad while sitting for so long (1.5+ years). Do rings go bad while sitting?

[jlevie]

So if you can still see the crosshatch, the piston rings are still good?

Seeing the cross hatching only tells you that the cylinder bores aren't worn. It doesn't say anything about the condition of the rings. You have to pull the pistons and check clearances and end gap to assess the condition of the rings.

[Jean]

If you have it out of the car might as well do it properly and do a once over ;) Bearings,rings,gaskets. The bottom end is actually simple, compared to top end imho.

[Miasma]

If the gap in between the pistons and rings look clean and not marred up, No visible rust, There is no ring ridge, And the cross hatch is still good you have a good chance they are still good. But I would rebuild the bottom end after letting it sit for so long. I can help you with that if you decide to delve into it mang, I have rebuilt a few motors.

[Jordan325iC]

If the gap in between the pistons and rings look clean and not marred up, No visible rust, There is no ring ridge, And the cross hatch is still good you have a good chance they are still good. But I would rebuild the bottom end after letting it sit for so long. I can help you with that if you decide to delve into it mang, I have rebuilt a few motors.

May take you up on that. Though right now I am leaning toward your block if it came out of a running car, and you still have it.

[StereoInstaller1]

OK, here is the deal. If you have any significant ring ridge, time for a bore/hone/pistons and rings and bearings full on rebuild. Ring ridge means it is shot. Rare as hell on an M20, especially under 300,000 miles. These things are TOUGH!

Personally, here is how I see it: No ring ridge and LOTS of cross hatch means the rings never "seated" well.. Likely, glazed to hell and back...but you could try and run it as is, but beat the crap out of it to build cylinder pressure to force the rings to seat...good luck. Might not be a bad idea to pop the pistons out, hone the cylinders and clean the hell out of the rings if you can see the glazing. Might never have been broken in properly, some people try and "baby" their motors, which never builds enough pressure in the cylinders, never forces the rings to seat. I am personally convinced these cars need to see redline every day, if not several times daily.

If it works, great, but otherwise, time for a tear down.

So if you have visible crosshatching, still no ring ridge, pistons look nice and clean (relatively clean, of course) I would buy a quart of Marvel Mystery Oil (MMO), squirt a goodly amount in each cylinder and rotate the crank. If you get huge smears of rust up and down each cylinder, or have extreme difficulty rotating the crankshaft, tear it down.

If it spins nice, no funny feelings or odd sounds, not a whole bunch of rust or nasty crap in general...AND...it isn't a major, life threatening deal to pull out a used motor and replace it, just run with the damn thing. M20s are tough as hell and will generally tell you if there is major trouble afoot.

Why tear down a perfectly good bottom end when it has 200,000 healthy miles to left in it?

If money is no object (what the hell are you doing on R3V?) and you want bragging rights, by all means, rebuild the bitch. If you want you car together sooner, concentrate on the top end. Get your valve springs tested to make sure they are all within 10% of each other, make sure the top of each valve is totally flat, of course new seals everywhere, find those 19lb injectors and MarkD chip (don't be an ebaychipbuyingfag, pay the man for his bad ass work!) maybe even find a mild cam...what the hell, $4.50 a gallon at 18MPG is STILL cheaper than $30,000 spent on a hybrid, and you cannot smile while driving a fucking PRIUS!

JMO, YMMV.

Luke

[Jordan325iC]

Thanks for the advice Luke. My car is actually turbocharged, so I'm already past the 19lbers/MD stage. The head on my current engine was rebuilt in 2005, so the top end should be good. And, I still get 17mpg.

[nando]

it's an M20.. it's like rebuilding a tupperware container. just take it apart and refresh it properly. bearings, rings, rod bolts, hone and polish the cylinders/pistons. put it back together. done.

[StereoInstaller1]

Thanks for the advice Luke. My car is actually turbocharged, so I'm already past the 19lbers/MD stage. The head on my current engine was rebuilt in 2005, so the top end should be good. And, I still get 17mpg.

So...wait a minute...SETA bottom end on boost?