Turbo options for a B21FT

Hello board,

I have an 84 B21FT and the turbo seems to be pulling oil into the compressor housing, quite a bit on the highway. It may be leaking into the turbine housing as well, but not as much because I don't see any oil at the tailpipe. However I do smell burning oil from time to time, if that's from coming through the intake into the cylinder or into the exhaust I do not know.

I was thinking of either getting the turbo rebuilt or buying a new one. I don't know squat about turbos, but I know tech must have evolved over the 34 years. The car has a dealer installed intercooler, if that changes things. Can people on hear recommend if it is best to keep the turbo the same or change it to something more modern. And if they recommend changing, then to what turbos specifically. I know with mechanical fuel injection it is not necessarily easy to change things. I am not really looking for more performance, I just hate having to check the oil every time I get gas. Thanks in advance for the help!

Mario

There are several things you can check before convicting the turbo. First you can check the turbo itself. With a cool engine you can remove the intake pipe on the turbo and check for play. Side to side play and lengthwise. See how sloppy it is. If you can move the compressor blades enough to hit the housing. it is completely worn out and will destroy itself meaning it won't be a good rebuild core.

Check for oil leaks. The oil return pipe at the block very often leaks and is a easy repair. The PCV system clogs on these cars as well and can cause excessive oil use. In addition the intercooler fills up with PCV goop and it is a good idea to remove it and clean it internally.

While the tech has evolved greatly you sound like it would be a good idea to spend some time learning more and getting experience with these cars. So I suggest you stick with the stock turbo for now. You can get a lot of fun with the stock T3 turbo before you need any upgrades and there are a lot of great threads here about upgrades when you are ready.

I've checked the entire car for leaks, nothing really. I have a really slow leak at the bellhousing, I can't tell if it is the transmission input shaft seal or the RMS. I had the shop top off the tranny a ways back I really need to crack it open and see if its low, but damn its a pain. The oil return line is weeping at the block but definitely not loosing the quarter to half quart per oil change that I am seeing. So I'm pretty certain the turbo is to blame for high oil consumption. The whole compressor housing and turbo to intercooler pipe is caked with serious oil deposits. Also the turbo has some wet oil on the bottom of it, it's so dirty I can't tell if a supply or return line is to blame. I have not removed any piping because I am worried I'll cause a vacuum leak, recently had one over there fixed that was giving me a high idle. I bought this car a year ago and it was pretty neglected, so I'm finally making progress towards the oil consumption problem. I was planning on replacing the oil separator in the PCV system. But I did not think a clogged PCV would blow oil only into the compressor housing. About the intercooler, the mechanic just had it out not that long ago when they removed the radiator to clean inside and out along with flushing the coolant system and a new 88deg thermostat to try and help with overheating. It helped, but it still starts getting hot climbing hills when warm out. I assumed they at least drained the intercooler, but who knows how fast its getting filled up. Should I drain the intercooler, drive 500-1000 miles, then measure how much comes out to quantify how much oil is being pulled into the intake. Yes some oil is evaporating in the turbo from heat if its reached the impellers, but would this help test how bad the turbos status is?

DL242gt, do you think all my oil consumption woes could really be caused by a clogged PCV? If so that would be a cheap fix.
Does feeling for shaft play tell one the life of a turbo, the less play the better? I don't think either impeller is contacting the housing, I do not here any horrible grinding or rubbing sounds. Also does the exhaust side need to be checked separately? How often does one journal bearing get worn way more than the other?

Thanks for the help

I would say from your description of issues that pcv system problems are part of the overall problems. A neglected engine probably has a couple problems going on. Checking the shaft play in a turbo will give a good idea of how worn the bearings are. The turbo is a common shaft so if you check the compressor side you will have a basic idea of the hot side wear.

Well it seems like a good time to do a compression check. Clean up the engine and evaluate the condition of air handling hoses and check carefully for vacuum leaks. With a properly working PCV system your oil consumption will be less. Fixing small leaks and making sure PCV works will help a lot.

Last summer I rebuilt an OE water-cooled T3 to replace the leaky, oil-cooled only T3 on my ‘83 244T. It wasn’t the easiest job...but it was a direct replacement for the turbo that came with the car, so I didn’t have to re-engineer the oil feed and oil return lines. I did have to purchase the water-cooled conversion kit from Volvo (it was still available at the time, special ordered from Sweden, Volvo P/N: 270840) and install that, but the kit had instructions provided and wasn’t painful to install.

Definitely size up the condition of your engine before playing around with the turbo...it’d be terrible for you to dump a bunch of money, time and effort into something that’s not going to solve any of the issues you currently have. Definitely make sure you’ve got good compression and a functioning PCV system before going too far.

Hey Baileywhite,
I saw in Bentley that it is a pretty involved job. Luckily mine is water cooled. It is an 84 and it has an intercooler installed so I guess it also got an upgraded turbo. I took the car to the car wash to clean the engine a bit to better judge how much the turbo is leaking. I happened to pull out the flame trap and the thing is so dirty it was barely passing air. So now I plan on replacing the oil separator. In your experience does the oil return tube on the oil separator normally also need to be replaced when replacing the oil separator box? Thanks for the help

Don't touch that oil return tube unless the engine is on a stand! Pray it doesn't crumble, reinstall new breather & O-ring on the mounting flange.

Ref. your turbo.... if your stone age Garrett is dead, why not upgrade to a Mitsu. 13C? Parts as common as grass, millions made, gain the 90+ manifold and use all the factory cooling connections. Who knows, a standard 13c oil drain for the B230FT might drop right in.

Someone in FS has a T25 pretty much complete, up on the auction block right now...... seller in Houston.

DET17 said:

Who knows, a standard 13c oil drain for the B230FT might drop right in.

Click to expand...

I don't think so. The B21FT turbo drain location is a couple inches different than B230:



But it's easy enough to buy an AN block return fitting (yoshi or sts), a turbo to AN adapter flange, plus a flex hose.

On the cheap I would go to to junkyard and get a 15g and 1990+ manifold, but you would have to rework the oil feed and return. And good luck finding an uncracked turbine housing, especially conical housings.

For a direct bolt in upgrade, I would do something like a 60 trim compressor T3. Or a T4 compressor.

On an '84 Turbo car there should be no flame trap. The flame trap was only used on the non-turbo cars. Should be a straight hose from the motor to the intake hose.

I also ran full synthetic oil in my car. Just make sure that there are no leaks. My car got to 400,000 miles on synthetic oil. A compression test will tell you how good the motor is. I got about 200,000 miles or so out of the rebuilt turbo that I installed. Some will do the rebuild themselves. I used a local guy.

bobxyz said:

I don't think so. The B21FT turbo drain location is a couple inches different than B230:

But it's easy enough to buy an AN block return fitting (yoshi or sts), a turbo to AN adapter flange, plus a flex hose.

Click to expand...

Ah, so it is. No B21s in my herd.

OP, if you do flex hose, do NOT use pipe thread connections..... that 900*F oil will find it's way thru them every time. AN 37* flare only, and you will have a chance at no leaks.

1/4 to 1/2 quart per oil change is low normal on these motors. Sounds like you have leaks. Clean everything well. Any diesel shop can rebuild your turbo, or you could send it to The Gpop Shop.
When replacing a turbo, most shops won’t warranty the rebuild unless you replace the oil supply and drain lines with new lines.