Heath

iTrader: (11)

I picked up a set of stock twins to tear apart just for the learning experience. One is leaky and the compressor wheel actually grazed the housing a bit. The turbine wheel must have eaten an apex seal because there are large chunks from the wheel. The other turbo has very minimal shaft play but appears it may be leaking some as well. I understand the stock Hitachi ht-12's use carbon seals, which are now old school.
Can anyone explain to me where the seals are located and what they look like? I notice what seems to be a thin metal seal (possibly carbon?) that is broken in multiple pieces, some still attached to the shaft near the turbine wheel. Is this indeed a seal? How many are there? What is the newer material used for turbo seals and can I use it on the ht-12's if I want to attemp a rebuild, again for the learning experience?
Since the turbine wheel is chewed it will definitely need to be replaced. Are the impeller shaft and the turbine wheel one unit or can the wheel be removed?
Any info pertaining to the questions above as well as anything else you have to share, such as where replacement components can be purchased and other misc. turbo info. is appreciated!

Heath

iTrader: (11)

So the stock twins are a mystery eh?

patriick

iTrader: (3)

I can't answer your questions about the seals, but I have a couple of rebuild kits I plan to sell. PM me if you're interested.

FEARED7

Hey Heath.

The stock twins are very finicky to rebuild. If you leave out one step, they will leak like a bastard.

Heath

iTrader: (11)

Hah, yeah that's what I understand. I'll have to be meticulous in my work I suppose. I don't know that they would even be used. I have gone to single. I just want the experience. I certainly wouldn't sell them if I wasn't sure of the quality.

redrotorR1

The carbon seals are located behind the backing plates in the turbine housings. You'll need some snap-ring pliers and a little patience to get them out. The metal that you found attached to the impeller shaft is a little weird. I've heard of turbos eating apex seals, but I've always thought that was someone's incompetent diagnosis. As far as replacing the carbon seals, I've been told that the seals are hard to come by. DO NOT re-use old ones. they will leak and your turbos will fail. If the compressor wheel has scored the inner surface, you will have to re-surface the housing. Glass-beading the housings and oil passages is critical. The buildup inside the turbos will result in early failure if not cleaned off. The turbine wheel can come off; but it would be smarter for you to replace the whole thing as the impeller shaft, turbine and compressor wheels have to be accurately balanced for the whole to thing to work.

Search on the web for turbo component vendors. There are tons of them ... although, many people who have rebuilt HT-12's complain about Turbo City and a couple other well-known vendor kits. Good luck.