I have a GTX now, finally.

[1st Gen]

Got a new GTX for my 91 Pro and I have a couple of questions.



First off, theres carbon in the cold side of the turbo that runs to the intercooler. Does this mean that the turbo needs a rebuild, and if so, would it be better to simply replace it?



Can I postulate how many miles this engine has on it by the condition of the turbo?



I did a compression check turning the engine over by hand and found that all the cylinders are right around 125psi. Does that indicate a sound engine?



What is a good turbo to put on this engine if I do choose to upgrade?



Thanks for any feedback. I do appreciate it.

 

[BlkZoomZoom]

All turbos leak some oil. How much carbon is in the tubes?

Even compression readings for all cylinders is always a good sign.

 

[1st Gen]

It's kind of hard to tell from this pic but I can wipe it out with my finger.

 

[BlkZoomZoom]

Me personally I wouldn't be worried about it unless the vehicle smoked or fouled plugs rather quickly. If it does neither of these and it still makes power than I would say it is fine. All turbos leak some oil, who knows the last time those pipes had been cleaned?

 

[1st Gen]

Me personally I wouldn't be worried about it unless the vehicle smoked or fouled plugs rather quickly. If it does neither of these and it still makes power than I would say it is fine. All turbos leak some oil, who knows the last time those pipes had been cleaned?

Thanks, you've helped more than you know.

 

[ChopstickHero]

is it the original turbo? if it was taken care of, then it should run fine. however, you can always ask a shop knowledgable about turbo rebuilding to clean it.

 

[1st Gen]

I think the turbo is original because it looks to be in about the same condition as the rest of the engine.

 

[1st Gen]

my engine

 

[BoOsTiN]

Got a new GTX for my 91 Pro and I have a couple of questions.



First off, theres carbon in the cold side of the turbo that runs to the intercooler. Does this mean that the turbo needs a rebuild, and if so, would it be better to simply replace it?
NOt quite. Remove the J-pipe from the compressor inlet. Check to see if the wheel spins freely. Then move side to side to make sure the blades do not come in contact with the housing. It will move slightly.
Can I postulate how many miles this engine has on it by the condition of the turbo?
No


I did a compression check turning the engine over by hand and found that all the cylinders are right around 125psi. Does that indicate a sound engine?
Always a good thing.


What is a good turbo to put on this engine if I do choose to upgrade?
VJ-14/11 hybrid.


Thanks for any feedback. I do appreciate it.

Join this:
http://autos.groups.yahoo.com/group/323gtx/

 

[1st Gen]

Join this:
http://autos.groups.yahoo.com/group/323gtx/

Thanks for the heads up. I joined this moring when I got home form work.

 

[slayer4u]

www.mazda323performance.com/forum is a good place to ask. I'm the BG mod over there.

Btw this is the 1.8 or 1.6? if it's the 1.8 then it came with the VJ-20. the 1.6 cam with the VJ-14.


On the subject of the turbo upgrade the VJ-11/14 hybrid is an excelent upgrade for the 1.6 and will require no custom parts. Some people are using T-bird turbos but that will require some custom work.

 

[1st Gen]

www.mazda323performance.com/forum is a good place to ask. I'm the BG mod over there.

Btw this is the 1.8 or 1.6? if it's the 1.8 then it came with the VJ-20. the 1.6 cam with the VJ-14.


On the subject of the turbo upgrade the VJ-11/14 hybrid is an excelent upgrade for the 1.6 and will require no custom parts. Some people are using T-bird turbos but that will require some custom work.

It's a 1.8

 

[stef_nz]

your turbo isn't necessarily leaking oil, the black goo in your compressor side could be blow by which is being recirculated from the rocker cover breather.

 

[1st Gen]

your turbo isn't necessarily leaking oil, the black goo in your compressor side could be blow by which is being recirculated from the rocker cover breather.

If it was blue, then I would think yea, its oil, but its black, and almost powdery. It doesnt smell either. Carbon huh, ------.
?

 

[stef_nz]

blow by is normal, it's just a matter of how much you get and it would be unusual to see that much in your compressor housing. i'd have to say that the pcv would need to be mighty blocked to spew that much gunk out of the side breather but i guess it could happen.
usually most of the vapor/sludge settles in the intake manifold (lousy emmissions control (fight)) if the pcv is working properly but if it's not working (and you are pressurizing the crankcase) then the other breather will dump the oily, crappy stuff into your intake pipe before the compressor inlet.
if it were just leaking oil i'd expect it to be less carbon-like and more oily if you know what i mean? (confused)

 

[1st Gen]

blow by is normal, it's just a matter of how much you get and it would be unusual to see that much in your compressor housing. i'd have to say that the pcv would need to be mighty blocked to spew that much gunk out of the side breather but i guess it could happen.
usually most of the vapor/sludge settles in the intake manifold (lousy emmissions control (fight)) if the pcv is working properly but if it's not working (and you are pressurizing the crankcase) then the other breather will dump the oily, crappy stuff into your intake pipe before the compressor inlet.
if it were just leaking oil i'd expect it to be less carbon-like and more oily if you know what i mean? (confused)

I'll take a look at the PCV when I get home, right now, I gotta go. Thanks bunches.

 

[1st Gen]

Wouldn't there be carbon on the intake side of the compressor if it was the PCV valve?

The intake side is clean as a whistle.

 

[stef_nz]

there should be carbony s*** IN your intake manifold but the fresh air breather shouldn't be venting into the intake on the pressurized side of the turbo - that would be disastrous. the fresh air breather should exit to the low pressure side of the turbo.

that said, i do find it strange that the black s*** is only in the inlet of the compressor..... keep digging, someone else may have an idea

 

[mike_moss]

I'm sure whatever you're finding is normal for a motor of that age. No need to worry.

 

[1st Gen]

I'm sure whatever you're finding is normal for a motor of that age. No need to worry.

Thanks.