Hi, I want to rebuild a T25 turbo, anyone know where to get the bearings and seals? Thanks

are you going to do them yourself ??

 

steve

I know that Colin Dick - dick300 has done it - try a pm to him

Thanks Willeo, I looked and he dosnt want emailing, so maybe he will read this and contact me. I thought I would have a go, cant be hard they are too simple, some people say they have to be balanced afterwards, not sure why but I dont know. Kits are on Ebay for about 50 dollars and there is nothing to them!

some people say they have to be balanced afterwards, not sure why but I dont know.

 

Because the assembly will end up rotating at 120,000 RPM, so any tiny imbalance ends up creating enormous forces, which destroys the bearings & seals in double quick time.. (and/or the housings, if you're unlucky)

 

It can be done yourself, but you need to mark the location of each piece that assembles onto the main shaft relative to each other piece, so you know that you are assembling them all back in exactly the same position they were in before.. Otherwise you'll be doing it all again after a week.. (actually, the last off balanace turbo I had lasted a whole 15 miles...)

 

The reason it costs a bit to get them done professionally is the time and the machinery used - machines that can balance a rotating assembly to the degree necessary (without having to spin everything up to operating speeds) are very, very expensive (think.. house..) :)

 

HTH,

Aaron

Thanks Aaron, so if you re-assamble as it was dis-assembled are they OK?

Because the assembly will end up rotating at 120,000 RPM, so any tiny imbalance ends up creating enormous forces, which destroys the bearings & seals in double quick time.. (and/or the housings, if you're unlucky)

 

It can be done yourself, but you need to mark the location of each piece that assembles onto the main shaft relative to each other piece, so you know that you are assembling them all back in exactly the same position they were in before.. Otherwise you'll be doing it all again after a week.. (actually, the last off balanace turbo I had lasted a whole 15 miles...)

 

The reason it costs a bit to get them done professionally is the time and the machinery used - machines that can balance a rotating assembly to the degree necessary (without having to spin everything up to operating speeds) are very, very expensive (think.. house..) :)

 

HTH,

Aaron

 

Got to agree with Aaron here this is one job that really is not a DIY job , as Aaron says turbo's are usually tested to in excess off 150,000 RPM if that is even slightly out off balance you could cause a massive amount of damage

 

Ryan

Thanks Aaron, so if you re-assamble as it was dis-assembled are they OK?

 

Theoretically yes - Ash Powers (AshsZ I think) on TTnet rebuilt his own turbos and they're still fine.. however, that man can build just about anything out of duct tape and bailing wire, so...

 

Personally, I wouldn't risk it - if you get it even a millimeter off you're going to end up pulling the engine again to change the turbos, and you might even wind up with cores that are totally toast and no longer rebuildable..

 

In short - it could end up more costly than just shelling out to get them rebuilt in the first place..

 

BTW - do enough Googling and you'll find a write up on how to rebuild a turbo in the end, I know it's out there as I did find it once.. just can't find it again, d'oh!

Oh yes - forgot to add.. The worst case scenario if you don't get it exactly right:

 

You end up with an unbalanced core assembly, which smashes the bearing to bits, flails around and slices big chunks of aluminium compressor housing off, before firing them through all your cylinders..

 

Now that'd hurt ;)

 

Also, FWIW, I believe that if your turbos ended up needing rebuilding then the core assembly is probably no longer in balance anyway, and could do with putting on a balancing machine - afterall, it's been doing 150,000RPM for what.. 10 years probably, that's a lot of wear - and the initial failure could well have been caused by an out of balance condition..

 

Hard to tell without expensive measuring gear sadly..

I hear what you say, I would not try this on my Z, but IF I try, and I am not at all sure I will now, it will be on a 200sx, loads cheaper and easier to work on. (I know I am a coward) Thanks again

Ahh well then, that's ok.. doesn't matter if it dies.. Er.. I mean.. ;)

 

At least you can pull the turbo without pulling the engine in the SX (IIRC), just listen out for the turbo squealing - if it squeals badly, it's out of balance (generally speaking)

Thats exactly what I thought, 3/4 of an hours and its off.