Supra Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
202 Posts
Discussion Starter #1
I did my first 7m rebuild a few months ago and upon startup had water in the oil. So I took it apart and started over. I took the head and block to a new place to have machined to accept a MLS gasket. I started the car up yesterday and deja vu, coolant and BLACK smoke coming from the back of the turbo. I don't have the downpipe hooked up, so no o2 sensor either. Im befuddled. I took no shortcuts and double and triple checked my work. The head was pressure tested, and passed just as it did the first time, I don't know how the block was tested but supposedly it was. What can cause this much coolant loss? I have too much time and money invested now to not fix it. But I have to get it right this time. Coolant should mean white smoke should it not? Yet, sure as can be, a puddle of water under the exhaust side of the firewall and the firewall is blackened with whaqt looks like carbon deposit and smells like gas. Someone point me in the right direction? There is def coolant in the oil, again. Where the pcv is on the valve covers theres some crystallization there from antifreeze. Bad block? Could the head be bad although it was pressure tested?
 

·
Registered
Joined
·
982 Posts
I can't even begin to imagine how stressed and pissed off you are to be doing this your third time. Takes a lot of determination to do this again. I would've said fuck this and brought it to someone. The only reason oil and coolant should ever mix would be bc you incorrectly installed the head to the block. If anybody else knows a way the 2 could mix put your input bc I dont. Have you gotten your block decked and checked? If not there's your problem. The slightest imperfections cause this to happen.
 

·
Registered
Joined
·
982 Posts
Sorry I didn't realize you said the block was tested too. Coolant burning is white smoke and has a sweet scent to it. Where does the coolant appear to be coming from on the exhaust side? Does it look like it's coming from where the head and block meet?
 

·
Master Shit Fixer
Joined
·
3,557 Posts
Block or head has a crack in it?
 

·
Registered
Joined
·
202 Posts
Discussion Starter #5
I swipe my finger on the exhaust part of the turbo and theres antifreeze. As far as head and block being tested, the block was "checked out" by a reputable shop and the head was pressure tested but I don't know what all the pressure test involves. Would it see a crack in the water jacket? The head and block were both machined smooth as to accept mls gasket. I don't know how to tell if its the head or block causing this. Im def close to the point of giving up, have I not so much time and money tied up in it I may well have given up. My pride is a little hurt though. I was meticulous.
 

·
Registered
Joined
·
202 Posts
Discussion Starter #6
Short of the trial and error, which would be expensive, replace the head and block, I don't know what to do next. The place that machined my head and block said my head studs were bottoming out causeing incorrect torqueing and that's how coolant got between the gasket surface and block and gasket surface and head. There is a difference this time though, last time coolant could be seen seeping from between the block and head. This time coolant can only be seen in the exhaust and oil, not seeping from the mating surface.
 

·
Registered
Joined
·
982 Posts
I tell you it it highly unlikely for the block to be cracked. People throw over 40lbs of boost at it and it never cracks. If you take the head off, you may possibly need to re thread the block. This could be difficult bc it's an iron block. If you do that then put the head on and try again, it could fix your issue. It makes sense to me.
 

·
Registered
Joined
·
202 Posts
Discussion Starter #8
They done that at the machine shop prior to me putting it together. That was their fix. I been thinking the common denominator both times has been the same head. Maybe its cracked???? I have not idea. If I go out and buy a used head, spend money to have it honed, my time to dismantle and reinstall it, then if its not fixed im back as square one. Id like to know for certain my issue before I go fixing stuff. The first go around as I said there was coolant under the gasket, a cracked head cant explain that I wouldn't think,
 

·
Registered
Joined
·
549 Posts
When the machine shop did the block, was the back lower timing cover bolted to the block? If it was not, it'll push the head up, resulting in a head gasket failure.
 

·
Registered
Joined
·
369 Posts
Trey, its David from FB. Is the turbo oil and coolant cooled?
My thoughts as well^ you mentioned coolant on the exhaust housing of the turbo. If its a ct or similar it is water cooled and also has oil running through it. IF the turbo is completely fubar it could be allowing coolant into the oil and also spitting oil past the seals causing the black smoke?

Since the block and head were both checked both times the turbo may be the 3rd common denominator that was overlooked. I haven't seen that before but it could cause your symptoms.
 

·
Registered
Joined
·
80 Posts
what head gasket are you using there was a particular gasket that had rivets that would not let the head seat correctly. also the head stud story they gave you is bs if you used the wrong bolts that where to long for your application then maybe that could be possible but not with studs. I would pull the head and examine the gasket very carefully to see if you can determine source of the leak also put a straight edge on the block and head to check for flatness. It's going to be one of 3 things your head,block or gasket the only other thing I can think of is if your putting the head gasket on backwards and don't laugh I've seen that done before.
 

·
Moderator
Joined
·
4,932 Posts
Studs/bolts should fit no problem, if they are bottoming out they are incorrect and would be a good place to look first for cracks.

+1 to din, what HG are you using?

Hard to say if its just loose bolts causing the leak or if something is cracked...
 

·
Registered
Joined
·
202 Posts
Discussion Starter #17
Im going to check wverything out. The facts are, it smoked like a train, but I wasnt using an o2 sensor either. Water cane out of the back of the turbo, oil cooled. The is visible crystallization of antifreeze on top of the valve covers where the pcv hoses are. I drained some oil last night and I couldnt find a sign of water but it smells big time like gasoline.
 

·
Registered
Joined
·
1,136 Posts
Im going to check wverything out. The facts are, it smoked like a train, but I wasnt using an o2 sensor either. Water cane out of the back of the turbo, oil cooled. The is visible crystallization of antifreeze on top of the valve covers where the pcv hoses are. I drained some oil last night and I couldnt find a sign of water but it smells big time like gasoline.
New engine, will produce some water due to the heat it is creating. Crystallization isn't a huge issue on the PCV side of things. I also think the turbo is causing some moisture as well. Remember, were in FL. And its been dipping to the 60s and 50s at night and then shooting to 80s. So what will appear on things. Your car is OVER FUELING. Black plugs and pistons is an indication of over fueling. So is FUEL in OIL. You washed the cylinders out. I was not aware of NO O2. Fix that, part of your over fueling issue.
 

·
Registered
Joined
·
202 Posts
Discussion Starter #20
This weekend in going to get my downpipe fabbed up, change spark plugs, change the oil and try again. Ill report back when I have done these things.
 
1 - 20 of 22 Posts
Top