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EA82T Turbo Cooling


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I did a bit of searching, but didn't come across much info on this.  In my seemingly neverending (but getting closer!) quest to rid my EA82T of all coolant leaks, I think I found that my turbo may be seeping coolant.  This would explain the coolant smell (as in turbo=hot, coolant seeping onto it=smell), and the fact that I still have coolant disappearing.  Though after replacing intake gaskets/waterpump/etc the coolant loss rate has dropped drastically.  

 

Has anybody experienced a coolant leak from their turbo before?  I was looking at rebuild kits, but they seem to only come with bearings and such, no seals.  Any advice on sealing this sucker back up?  I'm relatively new to turbo's and hoping for some advice before tearing into it.

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The coolant chamber on the turbo is a casting with no seals except at the 2 hose connections.  The top hose gets very brittle due to very hot fluids in it (I have had a couple literally crumble during attempts to remove them), and the bottom hose (which snakes up under the turbo from its fitting in the right-side head) is a pain to get at and almost impossible to routinely check.

 

I have heard of one or two people claim that there turbo was leaking internally, but I have never seen any proof, just anecdotal information.

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Can those hose connections be drilled out, tapped and an aftermarket tab put in there?

 

Just trying to think outside the box.

Also to help with general coolant temps I've got a mate that has put a small motorcycle radiator between the turbo's return line and the engine - the radiator mounts neatly out the front of the stock AC radiator up front.  He's done this with both of his EA82Ts and reports no heat issues in summer stop start traffic (35+ deg C).

 

Cheers

Bennie

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Can those hose connections be drilled out, tapped and an aftermarket tab put in there?...

Is this a typo, or am I getting tripped up by our "common language" issue?  Not quite sure what an "aftermarket tab" is.

 

Not sure what if any good your mate's extra radiator offers.  My understanding (subject to being corrected by reality :rolleyes:  ) is that there is little flow through those hoses while the engine is running.  Their main purpose is to be a thermosiphon cooling system after the engine is shut off to prevent excessive coking in the bearing housing. 

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Can those hose connections be drilled out, tapped and an aftermarket tab put in there?

 

Just trying to think outside the box.

 

Also to help with general coolant temps I've got a mate that has put a small motorcycle radiator between the turbo's return line and the engine - the radiator mounts neatly out the front of the stock AC radiator up front.  He's done this with both of his EA82Ts and reports no heat issues in summer stop start traffic (35+ deg C).

 

Cheers

 

Bennie

I don't understand how a small heater core size radiator could be put on the turbo return.For one even though not alot of fluid actually flows out the return while its running,It has to be as free flowing as possible-straight down into the oil pan with minimal bends, otherwise oil would back up into the turbo and leak into either the exhaust or intake.If what your are describing is true I bet that your friend has blue smoke out of the exhaust pipe on decel,maybe even a bit on hard acceleration.Not to mention oil consumption issues. 

 

On the other hand an oil cooler is almost mandatory on turbocharged engines.An oil cooler would even help an EA82T run cooler.

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Is this a typo, or am I getting tripped up by our "common language" issue?  Not quite sure what an "aftermarket tab" is.

 

Not sure what if any good your mate's extra radiator offers.  My understanding (subject to being corrected by reality :rolleyes:  ) is that there is little flow through those hoses while the engine is running.  Their main purpose is to be a thermosiphon cooling system after the engine is shut off to prevent excessive coking in the bearing housing. 

 

Use one of these appropriately sized:

 

large_2378_2378_90hb-4x4-hose-barb-brass-photo-1.jpg

 

Sorry about the image size, I've borrowed it from another site...  This is what I meant by aftermarket tab - I couldn't remember what it was called, but it's a barb over here...

 

I don't understand how a small heater core size radiator could be put on the turbo return.For one even though not alot of fluid actually flows out the return while its running,It has to be as free flowing as possible-straight down into the oil pan with minimal bends, otherwise oil would back up into the turbo and leak into either the exhaust or intake.If what your are describing is true I bet that your friend has blue smoke out of the exhaust pipe on decel,maybe even a bit on hard acceleration.Not to mention oil consumption issues. 

 

On the other hand an oil cooler is almost mandatory on turbocharged engines.An oil cooler would even help an EA82T run cooler.

 

Ummm... I'm talking about coolant, not oil!

 

I would recommend an oil cooler too - not that I've got an EA82T, as mentioned it's a mate's EA82T and it must work as it's his daily drive for work, the other is his dedicated offroad tourer with the same engine setup.

 

I hope this clears things up a bit!

 

Cheers

 

Bennie

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I know them as barbs, too.  I am not sure what advantage you might be thinking of in using a barb fitting, but IMHO there isn't anything useful to be gained with substituting a barb: the existing fitting doesn't tend to leak at that part of the connection, and I think the barb would make hose removal near impossible without slitting the hose. 

 

Going to hard-lines might reduce maintenance worries, and that could be done either with the re-tap as you suggested, or (better, in my opinion) would be to go to an hydraulics shop and get a banjo fitting that you can connect to a hard-line.

 

To OP:  Sorry for the deviation from your topic. :)  The upshot is, in my (limited) experience, the turbo itself does not leak coolant.  It doesn't need to leak, as the rest of the engine has plenty of places to leak.

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I did a bit of searching, but didn't come across much info on this.  In my seemingly neverending (but getting closer!) quest to rid my EA82T of all coolant leaks, I think I found that my turbo may be seeping coolant.  This would explain the coolant smell (as in turbo=hot, coolant seeping onto it=smell), and the fact that I still have coolant disappearing.  Though after replacing intake gaskets/waterpump/etc the coolant loss rate has dropped drastically.  

 

Has anybody experienced a coolant leak from their turbo before?  I was looking at rebuild kits, but they seem to only come with bearings and such, no seals.  Any advice on sealing this sucker back up?  I'm relatively new to turbo's and hoping for some advice before tearing into it.

 

You more than likely have either a cracked cylinder head or loose cylinder head bolts.  You can retightened the cylinder head bolts in a couple of hours by removing the camtower cover, removing the top oil lubication tube and getting a 3/8" x 17 mm socket in there.  If you find that they are all tight, then you should think about removing the cylinder head and replacing it with a GEN 3 cylinder head.

 

The heads can crack between the valves or crack at the fin in the dual exhaust outlet that separates the individual cylinder exhaust outlet.  If you are getting considerable white exhaust on startup, then you likely have the exhaust outlet crack.

   

If you look on the bottom of the cylinder head, there are the raised letters "EA 82".  If there is a line beneath the letters, then it is a GEN 2.  If there is a rectangular box around the letters, then it is a GEN 3.  If you have neither, then it is a GEN 1.  From my experience GEN 3 last longer than either GEN 1 or GEN 2.  But there are others here who have a different opinion.

 

If you want some GEN 3's that you want to take a chance and have some cracks rewelded, then I can sell you some for $50 plus shipping.  You will likely have difficulty in finding any GEN 3's and it will be nearly impossible to find some that have no cracks.

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Going to hard-lines might reduce maintenance worries, and that could be done either with the re-tap as you suggested, or (better, in my opinion) would be to go to an hydraulics shop and get a banjo fitting that you can connect to a hard-line.

 

The banjo bolt idea is a much better way to go in my book.  I only thought of the barbs as this is what we do with the inlet manifold etc when their hose tabs corrode out - I'm not a turbo boy but thought the suggestion might help out ;)

 

Cheers

 

Bennie

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Save yourself some trouble.

 

Pull the exhaust pipe off the heads.....look into the exhaust passages and inspect the area at each end of the "wall" that divides the 2 exhaust chambers.

 

There will be a crack there, most likely on the "inner" side, closest to the block.  Most likely on the passenger side too but common to happen to both.

 

If it's driving well, not overheating when full of coolant.......Drive it gently, keep it full of coolant, and enjoy it while it lasts.

 

If you start trying to "fix" it.......your gonna end up swapping motors.......and eventually the on;y fix is to EJ it.   You'll never be happier with your car than with an EJ22.

Edited by Gloyale
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