Kmenex Posted June 26, 2017 Share Posted June 26, 2017 Greetings, Anyone out there maybe help me figure out what's going on? Just replaced left and right head gasket and timing belt and water pump. After putting engine back in I added oil and coolant by slowly filling radiator with air bleed line open… then I started car, ran very smoothly, let it idle for 30 minuets. Ran very well, got to temp, very steady rpm, no hiccups… let it rest twenty 20 min then checked coolant and oil and added more. Next I took it for a test drive, 30 miles… ran perfect, like a new car. I was having power issues prior to repair now no power issues.. strong runner. Let it sit over night then started it up this morning… ran fine but 10 minuets in I noticed the temp gauge was sky rocketing… pulled over instantly let it idle. I noticed smoke was entering the cabin, maybe coolant vapor. Turned on the fan and smoke poured out… then the fans kicked on and I'm guessing the thermostat opened up and it went right back down to temp and stayed steady both while in gear and coasting.. no more smoke coming into cabin… Can anyone help me understand what's going on? I dont think it's the head gasket leaking as there was no power disruption at all and when was neutral coasting down hill no temp changes. Maybe a leaky hose? Heater core clog? I'm open to suggestions. Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 26, 2017 Share Posted June 26, 2017 (edited) details on car might help, model, miles, new to you, general condition, etc.did the vapor smell sweet - toasted marshmallow smell? have you checked coolant level in the radiator?did you install a new thermostat? it MUST be OEM-style; Edited June 26, 2017 by 1 Lucky Texan Link to comment Share on other sites More sharing options...
Kmenex Posted June 26, 2017 Author Share Posted June 26, 2017 Sorry thought I posted info in original post. 170k miles 1992 legacy. Link to comment Share on other sites More sharing options...
Kmenex Posted June 26, 2017 Author Share Posted June 26, 2017 Did not install new thermostat, still using original oem Link to comment Share on other sites More sharing options...
86BRATMAN Posted June 26, 2017 Share Posted June 26, 2017 You most likely encountered a stray air pocket in the system. It can take a while for all of them to work their way out. 1 Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 You most likely encountered a stray air pocket in the system. It can take a while for all of them to work their way out. it seems to do it consistently at a specific time during warm up, around 7-10 min, then it stops and goes back down ( temp ) and smoke disappears. Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 27, 2017 Share Posted June 27, 2017 test thermostat on stove top for smooth operation? does the 'smoke' smell sweet-ish, like coolant? you can have the cooling system pressure tested, that might show source of a leak. Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 (edited) Alright... I've given the beast a look over, pretty little thing... Poor cobber deserves a good looking after I suppose... Had to drive about 40 miles today, had 4 starting and the issue evolved... Started staying at high temp, not coming down and smoke was limited ( sweet smelling by the way ) and coming right under the steering wheel ( heater core connection )... Literally having a panic attack all day as I just did the light surgery and girl had to use car while I'm in the city... So looking over noticed both of the hoses on the water pipe at the top of the block ( to and out of heater core ) were not clamped down!! One had peeled back and was sputtering out coolant in small little droplets.. the other was just lose and wet around the edges... Checked in the overflow coolant tank and saw one bubble medium size ( roughly .75 cm diameter ) coming up every ten seconds or so... Looked at the rate of sputtering and seemed like to be connected.... Clamped those sons of bitches down! Now my theory about the high temp is related to what bratman said: the water temp sensor is high up in the coolant system and the potential for air bubbles to enter through proximal lose hose leads to air bubbles getting trapped near sensor position, giving a false high engine temp.. Thanks all for input and being willing to read my rants!! Edited June 27, 2017 by Kmenex Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 Been idling steady twenty minuets, no smoke, no temp increase ( dead center ) no leaking Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 (edited) Just went on quick test drive... Temp shot up but was no leaking coolant... Vapor did start to form wind sheild but not like before.... Possible I have air bubbles in there I need to get out? Also no more bubbles appearing in resivour.. thinking clamping that hose fixed it. Edited June 27, 2017 by Kmenex Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 Another interesting note: when I took for small test drive and it was showing high temperature... After I got back I let it idle and took off radiator cap ( i has gloves and face sheild on) and it sprayed out but was cool to the touch? Seems like there is a clog somewhere in the coolant system... Worked last night when I test drove it but not this morning... Maybe thermostat failed on the cool down? Maybe air trapped in there? Maybe heater core clogged? Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 27, 2017 Share Posted June 27, 2017 (edited) 25 year-old thermostat might be getting sticky radiator might be partially clogged....who knows without testing/examination? start with the easy/cheap stuff and work your way up no streams of bubbles is a GOOD sign but, don't drive it when it's overheating - that's a recipe for destroying headgaskets for sure as a test, you can also run with the t'stat removed Edited June 27, 2017 by 1 Lucky Texan 1 Link to comment Share on other sites More sharing options...
Subaru Scott Posted June 27, 2017 Share Posted June 27, 2017 It sounds to me like your heater core is leaking, and possibly clogged as well. You should bypass it to find out for sure. You must remove the hoses from where they go into the firewall and connect them together with an elbow or some other type of union that won't kink the hoses. The heater core circuit is critical while the engine is warming up, to keep flow past the thermostat so it can open properly. 1 Link to comment Share on other sites More sharing options...
DaveT Posted June 27, 2017 Share Posted June 27, 2017 The problem with air in the system can be 2 things - when the air pocket builds up big enough, and gets into the water pump. Water pumps don't pump air well. If enough air can get trapped in the thermostat pocket, so that the wax pellet part is dry, it won't open in time to prevent overtemp. Definitely test the thermostat. Running over normal temp while low on coolant often leads to failing headgaskets. I'd be checking for air in the upper hose and the level in the recovery tank before every run until you get this figured out 1 Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 27, 2017 Share Posted June 27, 2017 watch coolant level in the RADIATOR while working on this problem - don't trust the level in the overflow bottle. Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 Thanks so much for input. I'm going to bypass the heater core first because it started having light coolant vapor and sweet smell prior to massive repairs, and the day I shut it down and opened it up it was having temp spikes and vapor... Highly suspect heater core is clogged due to erratic nature of temp motion... as well as staying stable temp at idling rpm... Until you apply increase rpm then maybe becomes too much pressure to flow normally through clogged core... When I took off the old head gaskets they were very wet and deteriorating with gummy reddish substance. Could easily see this, along with general coolant debris and erosion, to clog heater core... After i bypass I'm gonna idle it while facing up hill on incline and start trying to burp. Ah one last thing.... When I filled coolant initially I filled until it started coming out the bleeder hole.... And left the resivour empty... After few miles and starts now overflow is way over the full line and i notice the levels in the radiator have dropped. Suspecting large air hole. Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 Bypass the heater core let it idle for a long time temperature stable increased RPMs temperature started to rise Reservoir is full turned it off let it sit for a couple minutes something happened I heard a gurgling noise all of the coolant reservoir got sucked up into into the radiator and cooling system I'm thinking there was a large air bubble around the water pump area and it prevented thermostat from opening but now it's somehow opened and sucked everything up into the block hoping it'll stay stable on my test drive also there's water in the upper rad hose where's before there was not good sign right Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted June 27, 2017 Share Posted June 27, 2017 if it sucked in the coolant now, it may very well point to a problem with the heater core ,or one of its hose connections, allowing air into the system on cooling in the past. Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 (edited) Yes I noticed a slight residue under the dash looking like slow long term leaking. Test drive time! Thank you all so much for helping me understand. I love this car and have plans for it ( lift few inches, new wheels, make it a mnt vehicle )... Thanks! P.s: Arco gas sucks and makes you idle rough! Edited June 27, 2017 by Kmenex 1 Link to comment Share on other sites More sharing options...
Kmenex Posted June 27, 2017 Author Share Posted June 27, 2017 Test drive success! Stable temp, no check engine light... Strong running, great sounding timing.. Two New hg and resurfaced heads, water pump, timing belt and all pulleys, new CV joints.... Next up replace steering line boots and front brake... Then clutch and new tranny some day when they start acting up. Thank you all for providing such wonderful information and guidance. Link to comment Share on other sites More sharing options...
golucky66 Posted June 27, 2017 Share Posted June 27, 2017 I've had two subarus that with a bad heater core caused an over heating issue. Glad you got to the bottom of it Link to comment Share on other sites More sharing options...
Kmenex Posted July 9, 2017 Author Share Posted July 9, 2017 Greetings, So car has been running fine but now that I've done work on it I've started to notice every little thing and can't rest until it's back to normal. Maybe this is a good thing? Anyways there have been a few changes since everything got up and running and the overheating issue solved.. details as follows: The cooling fans constantly run now. I suspect the coolant temp sensor but wanted to pick the forums brain in regards to a few things. Also the manual transmission cable linked speedometer cable broke off at the point where it connects to the sensor inside the transmission. My bad probably when putting the engine back in. When I first changed the timing and head gasket, before fixing the over heat problem, and before the speedometer sensor broke, the idle rpm was dead still and the engine ran without any hiccups. Smooth, not even a slight wobbling jitter, just clean even running. However now it idles a bit rough, RPM at initial start is a bit higher than normal but then settles down after heating up, yet still has that little hiccup thing going on about every 3 - 5 seconds, and idle rpm doesn't stay still.. moves around maybe by 100 RPM fluctuation. Also engine gets up to temp very quickly, in 3 min as opposed to 10 or so, however that could be due to it being July...? Would this type of behavior be produced from a faulty coolant temperature sensor? Also could have the 20+ year old sensor been driven to failure after the one time the car was driven before the over heat problem was fixed? Maybe it got too hot and ruined the electronics. Any input welcome. Other than that car is running fine. Link to comment Share on other sites More sharing options...
Gloyale Posted July 9, 2017 Share Posted July 9, 2017 If you are using A/C or Defroster settings the fans will run full time. Otherwise, I'd check the CTS. Idle fluctuation coud be a PCV or IAC hose leak. The speedo cable may be able to be slipped back togheter. If it came apart about 3~4 inches up from where it screws to trans? There is a clip you can pry off and reset, it holds the snout of the flexible cable sheathing. Just press it back in. 1 Link to comment Share on other sites More sharing options...
Kmenex Posted July 11, 2017 Author Share Posted July 11, 2017 Speedo cable won't press back together, maybe I'm doing it wrong.. So I reset the ECU and fans worked properly, still rough idle.. however the next day fans started coming in again as soon as car was started... So thinking the CTS... Not sure if this will effect the idle though. I am aware that some ECU systems use coolant temp to adjust fuel air ratios but not sure about this one... Other culprit could be the original spark plug wires are still on there ( how much of a difference does this really make ? ), Problems with the intake system or throttle body: head gasket was failed for a while before replacing, giving ample time for all types of cruddy mixing to take place in various recesses... Pcv valve less than a month old... Perhaps throttle cables are not at correct tension ( doesn't explain the perfect smooth idling right after the hg fix )... Maybe the head gasket is failing again after a few weeks? Link to comment Share on other sites More sharing options...
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