DasWaff Posted October 8, 2006 Share Posted October 8, 2006 Hey all, I've been fighting coolant loss in my '86 GL-10 turbo for a month now and I'm stumped. Went over all the hoses, new water pump (changed it with the engine swap), heater core, all dry. Figured it had to be the intake manifold gasket...VERY carefully replaced gaskets, cleaned surfaces, cleaned bolts and threads, torqued bolts down to 13ft/lb. Still losing coolant... Symptoms: when I shut it off after getting it warmed up, there are noisy percolating/bubbling noises coming from the radiator hose on the passenger side. I tried to trace them (using the screwdriver as stethescope method) and they seem to end at the turbo. Is there some way I could be leaking coolant into the turbo unseen? Is there some other likely source that I'm over looking? Your thoughts would be appreciated. DasWaff Quote Link to comment Share on other sites More sharing options...
Skatedownpdx Posted October 8, 2006 Share Posted October 8, 2006 i dont think the bubbling coming from the passenger side has anything to do with your loss. mine does it and so do others that ive actually payed attention to. maybe your head gasketS? Quote Link to comment Share on other sites More sharing options...
nkx Posted October 8, 2006 Share Posted October 8, 2006 did you check the hose from hell? runs from the thermostat to the bottom side of the intake manifold. Quote Link to comment Share on other sites More sharing options...
DasWaff Posted October 8, 2006 Author Share Posted October 8, 2006 i dont think the bubbling coming from the passenger side has anything to do with your loss. mine does it and so do others that ive actually payed attention to. maybe your head gasketS? OK, good to know... I just finished installing this motor recently. Its a low milage (47K) used from NYBE. Has lots of power and runs smoothly, and seems to be fine. I don't see any other signs of a head gasket problem, so I don't think that is my source, although stranger things have happened. did you check the hose from hell? runs from the thermostat to the bottom side of the intake manifold. Yup, when I did the intake gaskets I had a close look at that beast, pretty confident there. I'm about frustrated enough to give up and sell her... well at least this afternoon I am. Thanks for your help all. DW Quote Link to comment Share on other sites More sharing options...
daeron Posted October 8, 2006 Share Posted October 8, 2006 if your engine is reaching temperature, and not overheating, and you are getting bubbles into your coolant system, that is a prime indicator that the headgasket has blown a hole between the combustion chamber and the coolant passageway. It NORMALLY manifests itself by bubbling into the overflow reservoir, because you are pumping cylinder compression into the coolant system.. have you checked your radiator cap?? have you checked the overflow for bubbling into it? I realize that you are hearing noises from the other side of the engine, which seems odd.. but as I said, the bubbling into the overflow (when engine is operating temp but not hot AT ALL) is a pretty sure sign that the gasket is popped. Quote Link to comment Share on other sites More sharing options...
beataru Posted October 8, 2006 Share Posted October 8, 2006 Your sure that your coolant system is pressurizing right??? if its not.. those bubbles that your hearing are boiling water.... its not supposed to do that unless its not pressurized! Just wanted to throw that in... Quote Link to comment Share on other sites More sharing options...
DasWaff Posted October 9, 2006 Author Share Posted October 9, 2006 Your sure that your coolant system is pressurizing right??? if its not.. those bubbles that your hearing are boiling water.... its not supposed to do that unless its not pressurized! Just wanted to throw that in... Ok... I went out and messed with it some more. It is not bubbling back into the overflow at normal temp. In fact while its running its not losing coolant as far as I can tell, system stayed cool enough to pop the radiator cap off and check, no problem, no bubbles. It seems to be losing coolant after its shut down from normal opperating temp. Still no visible steam or drips nor hissing hoses or fittings. I think Beataru is right... The high water temp after shut down is creating enough pressure to cuase a leak somewhere, compromising the pressurization, and that noise is boiling water. I'm starting to wonder if it has a fine crack in the intake manifold that only leaks when the pressure is high. That would match with what I'm seeing... and it would explain why it runs sort of clunky for a few seconds when it first starts up after one of these tests even when it has been allowed to cool down. It has to burn off the water that has leaked into the manifold. I should be able to test that theory by opening the throttle body right after shut down and having a look and listen, right? Quote Link to comment Share on other sites More sharing options...
heep70 Posted October 9, 2006 Share Posted October 9, 2006 Compression check? :cool: Quote Link to comment Share on other sites More sharing options...
NorthWet Posted October 9, 2006 Share Posted October 9, 2006 The bubbling you hear from the turbo area is common/"normal": It is the water cooling system doing its job. (Tech info that I have seen says it doesn't matter which way water flows through the turbo's water jacket, or even if it does at all while the engine is running. What matters is that one tube is higher than the other so that it can thermo-syphon after the engine is shut off. The boiling is part of the thermo-syphoning.) I have yet to get an EA82T to keep its cooling system sealed. Coolant always seems to leave them somehow. Sometimes it is the aforementioned "hose from hell", sometimes it is the turbo's outflow hose (to t-stat), and sometimes it is the turbo's inflow hose that runs from the head and under the turbo. I personally have resigned myself to constant monitoring, and considered installing a reserve-coolant tank under the spare tire. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 9, 2006 Share Posted October 9, 2006 The bubbling you hear from the turbo area is common/"normal": It is the water cooling system doing its job. (Tech info that I have seen says it doesn't matter which way water flows through the turbo's water jacket, or even if it does at all while the engine is running. What matters is that one tube is higher than the other so that it can thermo-syphon after the engine is shut off. The boiling is part of the thermo-syphoning.) Exactly. The heat from the turbo and hot exhuast is boiling the cooling after shutdown. It's basically supposed to do that. The EA81T's when first produced didn't even have water cooled turbo's. But Subaru found that people who didn't idle the engine before shutdown or that lived in hot climates had excessive failure's of the turbo units. They were recalled and fitted with the EA82 style turbo and cooling hoses. The EA82 inherrited this "recall" design to prevent turbo failure. GD Quote Link to comment Share on other sites More sharing options...
DasWaff Posted October 13, 2006 Author Share Posted October 13, 2006 OK... I think I found my specific problem. I started going over the cooling system with a fine tooth comb. I pulled my thermostat and tested it and two spares in hot water with a candy thermometer. One failed completely, the other two just barely opened at approx 98 degrees C. One was a Stant, the other two were OEM (including the one that didn't work at all). Hmmmmm... This sounds very familiar, like straight out of one of General Disorder's posts I believe. The leak was in the thermostat housing, back side, and was a tiny, flat, silent, fine mist which evaporated almost immediately... I saw it because of a beam of sunlight was refracting a rainbow in the mist, lucky fluke there. So now I'm thinking I may switch over to a slightly cooler thermostat, say 180 degrees F instead of the stock 192. Glad to be enlightened about the turbo thermo syphon. I assume that when the system is working correctly the thermo syphon releases its pressure to the overflow tank and then reclaims the coolant when everything has cooled?? Thanks everyone for your help, DW Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.