How To: dismantle CT12A's

[wiso]

ok most 1J have the classic rear turbo leaking oil right.

mine started suddenly but mine also has other problems not just oil leaks.

So anyway, i don't have the cash atm that i want to spend in singles, rebuild or even hilfowed twins off ebay. so the only other option is obviosly second hand. I found a set the owner said was in good nick, no oil. when i got them there was heaps of oil.

Most second hand units are like this. But what about the front turbo, most of the time this turbo is perfect, its just the rear is shot. now you can usually pick up a stock set cheap in this condition.

so here is how you dismantle the front turbo and turn it round to sit on the rear position.

your probably thinkg the turbos are the same so why don't you just turn one upside down, because it won't work unles you want to make custom pipework for oil feed, inlet, water. you have to rotate them.



ok.


once the turbos are separated off the dump, get the water lines and wastegate actuators off and out of the way.

you will see a large clip with a bolt either side around the centre of the turbo, undo the nuts and remove the clip. where this join is where you must separate, soak in wd40, then hold the intake side and gently tap around the exhaust housing of the turbo till the exhaust housing separates, make sure to hold it straight down so you do not damage the exhaust wheel as it falls off.



you will need to actially pull apart both turbos for this job to make the one good one to replace the rear.

front housing comes off by removing the large circlip. there is an o-ring seal to seal the turbo so it may just need a gentle leavering to get the turbo out of the housing.



in the front houisn there are 2 locating pins to rotate it to the front or rear position. same thing in the ehaust housing. I could not get the pinn out of the front housing so i dismantled the rear stuffed rear turbo and used that with the pin already in position.



put the turbo back in and circlip back into place to assemble the front. Now the exhaust side. you will need to use the original rear exhaust housing from the rear turbo. they look almost the same but there is a slight differance with the cloing position of the rear wastegate. if you use the front the wastegate will never close when connected to the acctuator.

carefully lower the front half of the turbo into the exhaust housing, line the pin up an push into position. refit the main clamp, and continue to put the waterlines and wasteagte actuator back on..

and there we go, you now have one almost new turbo for the rear without any leaks.




I found the rears with the oil leaks the oil tends to eat away at the ceramic wheel, so you are actually missing bits of it, so its can't be boosting very effieciently.


took me about 2hrs as i pulled hte dud apart first to see what they were like, i advise it.

[TC1600]

Cool, nice work.

+rep

[richzx]

Wow that's fantastic!!! Good on you I was only wondering today if they could be switched around when I was looking at my turbo's. Mine seem ok but no doubt the rear one will go at some stage. Defintaely +++reps for you.
Rich

[Ribfeast]

I heard that they could be clocked around like this, but had never seen it done Good writeup man! +rep
You may also want to make a list of what tools are required, eg circlip pliers etc

[BMWTurbo]

You can do roughly the same for 2jz turbo's also

[wiso]

hmm, there aren't many tools needed to do this. i just used a;

12mm spanner
10mm socket
long nose pliers (instead of circlip pliers)
can of wd40

thats all i used

[TTMX83]

Thanks for this write up. Awesome ++

[JZA70 R]

wiso when you say the rear turbo is prone to oil leaks, where does the leak come from? ...is it a internal or external oil leak and why is it always the rear turbo?

[Ribfeast]

I think it was the oil seal around the shaft on the exhaust side, but someone might be able to confirm.

[JZA70 R]

wiso where have you gone?

[wiso]

wiso when you say the rear turbo is prone to oil leaks, where does the leak come from? ...is it a internal or external oil leak and why is it always the rear turbo?

sorry man. the seal is internal, its inside tha main turbo you can see in the pics, the oil just leaks out into the exhuast housing and gets blown around by the exhaust wheel.


as for why the rear usually goes, i dunno, but in most cases it is true. maybe caused by heat, or i read somwhere once its due to the oil breather design of the series one having all the oil feed to the rear turbo cause extra strain on the turbo. there was some recall on it and got changed for the series two.

I have no idea pick your favourite

[wiso]

ohh and i have now since tested these turbos and they both work well, good spool, so the swap of housings has caused no issues

[JZA70 R]

reason i ask is because i just wanted to confirm that the oil leak problem you were talking about was the common one that causes smoke, that everybody gets and not a new problem you had found...

my turbos smoke (which one i dont know) im in the market for another pair of second handies in good condition obviously, however mine are back yard steel wheeled so it would be a shame to throw those away... any recommendations?

[JZA70 R]

wiso?








10char

[wiso]

well from what i can gather its the common problem, but i can't confirm unless i pull lots of rear turbos apart. but mine was leaking from the rear seal right behind the exhaust wheel