17 replies to this topic

[Redhill]

my 1988 gl turbo wagon was blowing lots of white smoke out of the exhaust so i pulled the engine and replaced the head gaskets, intake gaskets. resurfaced the heads, used subaru head and intake gaskets, took my time and thought i did a good job. it started right up this evening and is still blowing white smoke just like it did before. could the turbo be passing coolant into the exhaust? can i gut the turbo and plug the coolant and oil lines? thanks for any ideas, i'm kinda dissapointed, red

[AKghandi]

it might be the turbo. just use some vise grips with some padding and clamp the water in line and see if it goes away/

have you re-torqued the heads yet?

[mikaleda]

Does the smoke smell sweat? If not it is probably oil. How many miles on the engine? Did you check the piston tops when you did the heads could be a cracked piston. Check around your air filter for oil. Check your oil see if there is water in it. How did your valve seats look when you replaced the head gaskets. Also could be ATF lol check you gas tank last resort to see if someone didn't pour some ATF in your gas. I know oil smoke is usually gray

Edited by mikaleda, 13 December 2012 - 07:21 PM.

[Redhill]

thanks for the replys, the smoke (steam) is coolant, it leaves water on the driveway below the tailpipe. everything (pistons, valves, heads) looked pretty good, maybe just the usual cracks from valve seat to sparkplug threads. i have only run it about 30 minutes, do i need to retorqe subaru head gaskets? i will crimp the coolant line and see if the smoke quits. how long can i crimp the line and not fry the turbo? thanks again, red

[mikaleda]

thanks for the replys, the smoke (steam) is coolant, it leaves water on the driveway below the tailpipe. everything (pistons, valves, heads) looked pretty good, maybe just the usual cracks from valve seat to sparkplug threads. i have only run it about 30 minutes, do i need to retorqe subaru head gaskets? i will crimp the coolant line and see if the smoke quits. how long can i crimp the line and not fry the turbo? thanks again, red

Cracks? Did you have the heads crack checked? That could be the whole issue you may need new heads, but if it is blowing smoke you should have been able to see them.

Edited by mikaleda, 13 December 2012 - 07:59 PM.

[djellum]

the cracks in the head are common but not always harmless. if they go deep enough they can allow water from a coolant passage to get into the exhaust port.

Lost a turbo XT to this very thing.

You should be able to drop the exhaust and see, but it depends on how bad its leaking. Mine did it for quite a while before I had any real issues from it. it still ran and I traded it off to someone who put stop leak in it and ran it for a while themselves (not recommended).

something to at least look into.

[markjw]

I've done hg's in the past where I've let a lot of coolant drain into the Y pipe while removing the heads. Enough where I had to race up and down the road for 10min to burn it all out. You didn't say if you let it sit and idle for 30min or actually drove the car around. But make sure your white smoke isn't just residual coolant laying in the exhaust, before you start undoing all your hard work.

[skishop69]

Run it up to around 2000 rpm for 15 min or so. If you still have the CAT (or not) you've got coolant trapped in the exhaust. I've done HGs on engines that took 45 minutes to burn it out...

[rain_man_rich]

My 90 Turbo Loyale does the same thing intermittently throughout the cooler winter months. I've subscribed to this thread to watch your progress.

[Redhill]

I have thought about coolant left in the exhaust system, I just ran it at fast idle in the driveway for 20-30 minutes. maybe not enough to burn it dry. I will run it more tomorrow and maybe clamp the water off to the turbo to see if that helps. thanks for the ideas, red

[scoobiedubie]

The fin between the two exhaust channels that meet at the exhaust outlet, develops a tiny cross crack at one end of the fin. It apparently cannot be repaired. It leaks coolant into the exhaust stream without sending past the plugs. So a plug check would not reveal it.

If a plug check does show a slight white residue on one of the four plugs, then you would have a crack between the intake and exhaust valves there, that also leaks coolant. They fixed this with the mpfi turbo heads but not with the spfi heads, with their GEN 3's.

[Redhill]

OK, i started the car again today, no white smoke at first but it started again as the engine came up to temp, maybe not as bad. pulled out of the driveway and started up the road, i really had a "cloud" going on behind the car. I decided it would either go or blow, so I said a prayer, and let 'er rip. I really had smoke and some funky smells going on. In about half a mile it got a little better, another half mile down the road it cleared up completely. It could have been coolant left in the exhaust. I always get a lot of help from above, and i need it. thanks for the earthly help too, red

[Gloyale]

The fin between the two exhaust channels that meet at the exhaust outlet, develops a tiny cross crack at one end of the fin. It apparently cannot be repaired.

You are spot on. The turbo heads crack in this area VERY commonly. They can be repaired, but they ussually crack again later. I had a set welded up, put them on an engine and ran it about 20K miles before a rod bearing gave out. when I pulled the heads, only one was cracked!!

If a plug check does show a slight white residue on one of the four plugs, then you would have a crack between the intake and exhaust valves there, that also leaks coolant. They fixed this with the mpfi turbo heads but not with the spfi heads, with their GEN 3's.

The "fixed" Gen 3 heads exist. But they aren't really fixed. Slightly less prone to both types of cracks, but definately still not "fixed"

I'd say about 80%+ of the SPFI heads of any gen, and 100% of the Turbo heads have the Between the valves cracks......mostly not an issue though.

The turbo heads however, even "Gen 3" ones, see about a 90% cracked rate in the exhaust web. Most all of these leak some coolant. Athough I've seen many good running cars, that just barely seep, and have run a long time just topping off coolant.

I don't think it's very good for the turbocharger though:(

hopefully the OP of this thread just had residual water and oil in the exhaust pipe still.

[rain_man_rich]

OK, i started the car again today, no white smoke at first but it started again as the engine came up to temp, maybe not as bad. pulled out of the driveway and started up the road, i really had a "cloud" going on behind the car. I decided it would either go or blow, so I said a prayer, and let 'er rip. I really had smoke and some funky smells going on. In about half a mile it got a little better, another half mile down the road it cleared up completely. It could have been coolant left in the exhaust. I always get a lot of help from above, and i need it. thanks for the earthly help too, red

That's exactly what I did, and it worked. For a while, it still comes back now and then. Sometimes really bad.

[86 Wonder Wedge]

The 86 XT I had, had an 88 EA82T with Gen 3 heads and cracked between valves on all 4 chambers. And after the overheating, had the exhaust tunnel crack, but no evidence of water... definitely not immune, so if offered, don't overpay for gen 3 heads...

[rain_man_rich]

Redhill,

 

Any updates? Also, I have a question.  Does the engine run like it has a miss, or at least a partial miss,  when it's smoking?

[92LoyaleH4]

I'm going to assume you have a standard...but a leaking vacuum modulator on the Auto Trans can cause this...Granted mine only did it when i would turn, it sounds like your does it quite a lot more

[NickNakorn]

Hi,

 

'the smoke (steam) is coolant,'  are you positive that the smoke is coolant/steam because every exhaust will have some condensate - how much water are you losing in (say) a ten mile journey? Have you also ruled out worn valve-stem oil seals?