Where Do I Find Pistonrings For Rb25det?

[sirmiro]

Hi.

I wonder where i can find relatively cheap pistonrings, bearings and gaskets.

I've searches ebay but you in here might know more (as you always do).

I've made a compressiontest with this result:

Is there enough to change the pistonrings, headgasket and get sure the valves fit tightly?

The plan is to get RB26-rods into the engine when it's open and change the bearings to get the bottom ready for all my future plans. Do i need something specific to do this?

Or do you have better suggestions what to do?

Which parts do I need that i haven't wrote?

Which sizes on bearings/pistonrings? (I don't know anything about the engine and rather don't want to wait for parts...)

Edit: The engine has run 97000km according to dashboard.

Med vänlig hälsning

Micke

Edited April 14, 2010 by sirmiro

[pipster11]

pour a tiny bit of engine oil into each cylider and re measure the compression

if it evens out the rings need changing, if it stays the same then the head it at fault (or head gasket)

have a go at that and report back to us

[SRX720]

Is there enough to change the pistonrings, headgasket and get sure the valves fit tightly?

no it isn't enough, first you need to find out why you have low compression (doing what pipster11 has said is a good start) then work out what needs to be done from there. if the rings are worn you can;t just put new rings in.

you should talk to your mechanic or engine builder about what needs to be done.

unsure if RB25 and 26 rod lengths are the same, but this would probably be a good time to put them in.

[Stinky Rooster]

the only way a head issue would allow that much of a compression drop is if it has dropped a valve, or a valve seat, and the noise the engine would be making would make that quite apparent

I would be tearing the whole engine down myself, because that much variation is a lot more than just worn rings. Could be broken rings (in which case the bore may be damaged) or even a ring land - quite common for an RB that has been leaned out.

Either way, not good news

[32TAXI]

Who done the test? Was it at operating temp with throttle wide open, all spark plugs removed and even cranks (6-7) on all cylinders.

I would double check readings and also oil cylinders to see if readings change.

If compression comes back up with oil in cylinders = posibly rings - If no change on readings = posibly ring lands, holed piston or headgasket blown between cylinders..

Edited April 14, 2010 by RED513

[sirmiro]

I shall redo the test with oil in when possible.

We did the test in the garage with a cold engine, all plugs out and even cranks.

We did 2 tests and they show the same.

Do you think i shall disassemble the engine before ordering parts? This looks like it gets bigger for each time I think about it.

[pipster11]

I shall redo the test with oil in when possible.

We did the test in the garage with a cold engine, all plugs out and even cranks.

We did 2 tests and they show the same.

Do you think i shall disassemble the engine before ordering parts? This looks like it gets bigger for each time I think about it.

run the engine up to operating temp and then do it

nothing in the engine seals as well when its cold

[KiwiRS4T]

Do the compression test with the hot engine and try the oil trick.

If you do pull it down and find it needs a rebore and you want forged rods and pistons etc to make big power later it will cost thousands. Do the costings on parts and machining and then consider an RB30 block from RIPS:

http://www.ripsltd.com/products.html

[SRX720]

Do you think i shall disassemble the engine before ordering parts? This looks like it gets bigger for each time I think about it.

definitely! otherwise how are you going to know what you need to replace?