Jump to content
SAU Community

Recommended Posts

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). :D

I've made a compressiontest with this result:

902833_8l1hzr.jpg

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

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 by sirmiro

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

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.

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

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 by RED513

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. ;)

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. :D

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

run the engine up to operating temp and then do it

nothing in the engine seals as well when its cold

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • That still isn't a lot to go on. I don't have a Y50 Fuga Head Unit wiring diagram. I can say that a lot of nissans of that age shared head unit plugs, so if you are in Australia something like this would probably help: https://aerpro.com/app091# You plug that into the car loom, then either plug the head unit ISO into that (if it has ISO), or you buy and ISO adapter harness that you wire in. Bit of stuffing around, but once you have ISO its easy to change things in future.
    • It is a kunfine Android screen . Does anyone know the wirering diagram of the fuga ??
    • just an update to this, poor man pays twice  Tried sanding down the pulleys but it didnt do the trick. Chucked another second hand alternator in the na car which I got for free off my mate and its fixed the squelling. Must have been unlucky with the bearings.    As for my turbo car, I managed to pick up a cwc rb alternator conversion bracket + LS alternator for 250 off marketplace, looked to be in really good nick. Installed it , started the car and its not charging the battery.... ( Im not good with auto elec stuff so im not sure if this was all I needed to do but I verified such by using a multimeter on the battery when the engine was running and I was only getting 12.2v )   I had to modify the earth strap for the new LS alternator , factory earth strap was a 10mm bolt which did not fit the bolt on the LS alternator which was double the size so I cut it off , went to repco bought some ring terminals that fit, crimped it onto the old earth strap and bolted it up to the alternator , started the car and same issue. Ran like shit and was reading 12.2 at the battery.  For a "plug and play" advertised kit thats not very plug and play but alas.  My question is , am I missing something ? Ive been reading that some people recommend upgrading the stock 80 amp alternator fuse to a 140 amp but I dont see how that would stop the alternator charging especially at idle not under load.  Regardless ive pulled it out and am going to get it bench tested by an auto elec tomorrow but it would be handy to know if ive missed something silly or have done something wrong.   
    • My wild guess is that you have popped off an intake pipe....check all of the hoses between the turbo and the throttle for splits or loose clamps.
    • Awesome, thanks for sharing!
×
×
  • Create New...