tham1992

Anybody know what size piston I would order with a rebuild kit for a 1991 22re

bswarm

You need to measure the bore diameter to see...
A: if it already has oversize pistons.
B: if boring to next size is required.

tham1992

OK I was just wondering its an original motor

scope103

http://personal.utulsa.edu/~nathan-b...ne/69cylin.pdf (page 107)

What I believe BSWarm is saying is that even though your motor is "original," your cylinders could be sufficiently worn that you need to rebore them.

Why are you ordering new pistons? Your truck is close to 25 years old; if you're going to the trouble of getting new pistons, you might as well go to the trouble of getting the right ones.

tham1992

I am ordering new pistons cause I'm rebuilding the motor just don't have it tore down yet 3 and 4 valves barely have any compression and was told by the way the motor shut off going down the road it was probably the rings on the pistons

bswarm

You need to take it apart and measure the bore in many places. this will tell you if cylinder taper, excessive ridge near the top, etc. indicate if sending the block to a machine shop to bore it out to the next size will be necessary.

scope103

Reboring the block and fitting oversized pistons is, in my personal opinion, a BigDamnDeal. I think you'd be better off getting it apart before you start ordering pistons. Who knows, you might get yourself the correct bore gauge (even the cheap ones aren't very), and find out that your cylinders are okay. Or, just as likely, you'll find so much damage in the engine that you'll rethink the whole idea of rebuilding it.

I sure can't say which way it will go.

tham1992

I'm gonna tear it down before ordering

Shady Cadence

Yeah, let us know what you find.

With pictures.

tham1992

I will

shadowbirdie

Sounds like a huge deal for a 25 year old vehicle, doing it or having it done?
Unless you have the tools already, seems you're looking at a huge investment?
Long or short block seems a shorter way to go considering the investment you are talking about, that and the 22 plant, a great engine(all versions are a product made for US vehicles, not put in Toyota sold in other parts of the world) so I've always heard. I'm not experienced or motivated enough to take on something huge like that...
I picked one with a good strong engine to begin with, great deal for $1500, lots of fun smaller things to do, even a boneyard one after doing a thorough inspection and tests.

J Good Luck with that, yeppers keep us apprised..

wyoming9

iTrader: (1)

As was said there is no way to know just what you have.

Not only do you need to worry about piston size but bearing size as well.

This could get expensive real fast.

As you still have no idea of what is really wrong.

One cylinder with bad rings will not cause the engine to shut off going down the road.

I had one of these I could turn the engine over by hand with all the plugs in with just my hands .

not much power but it ran fine.

skypilot

iTrader: (1)

Get a hold of engbuildr.com and get a complete master rebuild kit from him. Now until you have the heads off and a micrometer and an inside mic you cannot tell how big an overbore you need. Mine I got away with a .020 oversize piston. but I know from experience that .010 wear at the top of the cylinder will cleanup with a .020 unless something happened besides 200k normal wear.

You don't want to punch it the full .060 without checking for core shift so you really want the minimum, and your machinist can tell you what that number is.