Coolant bleeding - not having much luck
#1
Race Director
Thread Starter
Coolant bleeding - not having much luck
Trying to bleed the coolant and its being a pain in the a$$. Maybe you guys can shed some light??
Ive only put about 300 miles on it since the engine swap in December d/t some random issues (fueling / starter = now resolved) and most of those miles were while it was cold out.
Last time I drove it was 2 months ago and after 3 runs on the dyno while driving it home the temp gauge was nearing the top black line but never crossed it (temp needle above the middle of the gauge) Pulled it into the garage and it puked coolant from the tank onto the floor out of the overfill hose.
Took it off the road for starter, camber plates, big reds, etc...
So jacked up the front tonight and filled the tank until it bled from the 12mm bleeder. (Coolant tank now overfilled) Started car, let get warm (heat cranked all the way), jacked up passenger side and bled, bled, looked ok but was running pretty hot (above the middle, but again wouldnt cross the top black line)
Both fans are kicking on, heater will never get "hot". While at temp and jacked up car drips coolant from the overflow tank as coolant is up around the coolant tank neck...
-At this point I shut it down and after talking with Dan J a few times he mentions the heater valve might not be opening correctly not allowing the system to bleed completely. Checked it and its working fine-
Start it up again and let it get warm, this time it sat in the middle of the temp gauge and the heat again never got really hot. Drove it to bed the brakes (wow) and it was running below the top black line again but never crosses it - pull in the garage and it pukes coolant again. Now the coolant has leveled to the same place it was after it puked a few months back (level to lip on coolant tank)
-Car runs great
-Oil looks fine
-Coolant looks fine
-Car doesnt smoke at all
-Recent motor swap with new thermostat, new waterpump, new n/a coolant tank, removed water cooling for turbo, old coolant tank cap, probably more I can't think of...
Am I missing something? Should I try another thermostat? New coolant tank cap just to be sure its sealing well?
Thanks guys,
Sam
Ive only put about 300 miles on it since the engine swap in December d/t some random issues (fueling / starter = now resolved) and most of those miles were while it was cold out.
Last time I drove it was 2 months ago and after 3 runs on the dyno while driving it home the temp gauge was nearing the top black line but never crossed it (temp needle above the middle of the gauge) Pulled it into the garage and it puked coolant from the tank onto the floor out of the overfill hose.
Took it off the road for starter, camber plates, big reds, etc...
So jacked up the front tonight and filled the tank until it bled from the 12mm bleeder. (Coolant tank now overfilled) Started car, let get warm (heat cranked all the way), jacked up passenger side and bled, bled, looked ok but was running pretty hot (above the middle, but again wouldnt cross the top black line)
Both fans are kicking on, heater will never get "hot". While at temp and jacked up car drips coolant from the overflow tank as coolant is up around the coolant tank neck...
-At this point I shut it down and after talking with Dan J a few times he mentions the heater valve might not be opening correctly not allowing the system to bleed completely. Checked it and its working fine-
Start it up again and let it get warm, this time it sat in the middle of the temp gauge and the heat again never got really hot. Drove it to bed the brakes (wow) and it was running below the top black line again but never crosses it - pull in the garage and it pukes coolant again. Now the coolant has leveled to the same place it was after it puked a few months back (level to lip on coolant tank)
-Car runs great
-Oil looks fine
-Coolant looks fine
-Car doesnt smoke at all
-Recent motor swap with new thermostat, new waterpump, new n/a coolant tank, removed water cooling for turbo, old coolant tank cap, probably more I can't think of...
Am I missing something? Should I try another thermostat? New coolant tank cap just to be sure its sealing well?
Thanks guys,
Sam
#2
Sam
Maybe it's happening because you haven't flipped your GRM calendar to June?
Jokes aside, have you tried a new cap yet? How does the gasket look?
Have you connected a bottle to the overflow line and driven it with some boost?
Close the bleeder and let it run for a minute or two then crack it again - does the coolant come out in a steady stream or do you get some air each time?
Maybe it's happening because you haven't flipped your GRM calendar to June?
Jokes aside, have you tried a new cap yet? How does the gasket look?
Have you connected a bottle to the overflow line and driven it with some boost?
Close the bleeder and let it run for a minute or two then crack it again - does the coolant come out in a steady stream or do you get some air each time?
#3
Rennlist Member
im thinking you may have blockage in your heater core somehow- may have to pull the line on the back of the head and the one on the back of the cambox pipe and flush it out- not sure why but its happened...
#5
Drifting
Warning: only do this in the confines of your garage....
Fill reservior. Clamp off reservior overflow. Clean off opening at top of reservior. Put wrench on bleeder screw and hold w/ left hand. Seal mouth to reservoir opening and apply pressure. Open bleed screw and relieve pressure. Repeat as necessary.
Does the car really feel that hot or are you getting a false temp reading? I've bled my car many times w/ the heater valve closed so I don't think that matters.
Fill reservior. Clamp off reservior overflow. Clean off opening at top of reservior. Put wrench on bleeder screw and hold w/ left hand. Seal mouth to reservoir opening and apply pressure. Open bleed screw and relieve pressure. Repeat as necessary.
Does the car really feel that hot or are you getting a false temp reading? I've bled my car many times w/ the heater valve closed so I don't think that matters.
#6
Sam, try running to the local Auto Zone/Advance Auto Parts store and see if you can borrow a coolant system pressure tester (one of them has a zero cost tool loan programs, I just can't remember which one). With the car cold and dry, pressurize it to 15psi, and look for any coolant leaks. After you are sure there aren't any leaks, then let it bleed thoroughly, top the tank off and bleed a second time. Start the car up, open the heater controls up and let it get to operating temp. Listen inside the passenger compartment for any "gurgling" sounds, if you are hearing any, then the problem is likely your heater core. If you are still having a problem at this point and you aren't hearing any gurgling, let the car cool down completely, and then pull the spark plugs one by one, and see if one or two of them are really clean or you smell antifreeze coming from the spark plug hole, which would indicate a possible headgasket problem. Knowing Dan and his work habits, I doubt thats the case, but it does happen and I wanted to be thorough here.
In my experience, I've have leaking heater cores but never a plugged up one in a 944, and you'll usually notice that mist on the winshield and smell inside the car if thats the case. Its not the most fun to replace, so lets hope thats not the case. If you have a problem, I'd bet on a hose clamp that gave out or small hose leak somewhere.
Regards,
In my experience, I've have leaking heater cores but never a plugged up one in a 944, and you'll usually notice that mist on the winshield and smell inside the car if thats the case. Its not the most fun to replace, so lets hope thats not the case. If you have a problem, I'd bet on a hose clamp that gave out or small hose leak somewhere.
Regards,
#7
I had a hell of a time with KNFPRTY's car, and i was filling it with a vacuum system, it kept puking coolant, ended up one of the end tanks was seeping, and system couldnt build pressure. I agree with using a pressure tester on the coolant system, and checking for leaks.
Mark
Mark
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#9
+1 on the rad cap, use the coolant pressure tester to check it as well.
Regards,
Regards,
#10
Race Director
Thread Starter
Thanks guys, excellent! I undid the cap this morning and it didnt seem pressurized, how long do they normally hold pressure for?
I haven't checked the radiator cap and Im gone all day traveling for work unfortunately. Ill go to Autozone first thing when I return and get the coolant pressure tester and do as you said Scott and report back. I havent heard any gurgling that I can remember but Ill listen closer after I pressure bleed it.
Secured a new cap from Euromotor Works just in case thats the problem. Figure mine is old anyways, cant hurt!
I haven't checked the radiator cap and Im gone all day traveling for work unfortunately. Ill go to Autozone first thing when I return and get the coolant pressure tester and do as you said Scott and report back. I havent heard any gurgling that I can remember but Ill listen closer after I pressure bleed it.
Secured a new cap from Euromotor Works just in case thats the problem. Figure mine is old anyways, cant hurt!
#12
Defending the Border
Rennlist Member
Rest In Peace
Rennlist Member
Rest In Peace
Pressure tester is a must. Car cold, engine and radiator areas clean (skip that last one Sam ), press it up AND monitor for a pressure drop. If you notice a drop, conduct a visual.
Found a couple of seeping clamps and a hairline coolant tank cap seal fracture this way.
Found a couple of seeping clamps and a hairline coolant tank cap seal fracture this way.
#13
Race Car
Having bled a mine quite a few times (both cars). I have to agree with the pinching the overflow hose and using the mouth to reservoir technique. Sounds bad but if the area is clean it is just like blowing up a balloon.
My 02
My 02
#14
Nordschleife Master
"In the 2002 annual report of the TESS data by the AAPCC, 6,077 exposures to ethylene glycol were reported in the United States, resulting in 40 deaths and 254 near-fatalities (Watson 2002)."