another tricky coolant problem

[kamineko]

so i've been working on Kas's BG5A TT, it blew the radiator side tank.

- replaced radiator and removed a RUST SAUSAGE! from the bottom hose

- bottom hose would not heat up

- removed thermostat, checked in boiling water. it opened and closed.

- heater core appeared blocked, ran garden hose through it both directions and it came clear

- ran garden hose back through engine side heater lines, came clear via top hose and water pump

- put all back together and the bottom hose is still pretty cold. does seem to warm up but not much? top side gets bloddy hot, then cools as the fans kick in

- LOTS of air noise from heater core with blip of throttle. more than i've ever heard before.

- coolant reservoir fills up quickly as engine heats up and the engine seems to suck it back in when cooling

- engine temp gauge does not rise above normal op temp.

i'm sure something isn't right.

is the thermostat opening too late? is there another rust blockage somewhere? pretty sure the pump is working but ?

i know there are lots of coolant threads, i've read them so please read my symptoms before posting generic answers cheers. Kas needs her car but i'm running out of time to spend on it.

[DRFVDR]

I would try not running the thermostat ( to eliminate that as the cause )

and bypass the heater core as it could still be somewhat blocked

[kamineko]

removed the thermostat, tested and it begins to open at 77C so working fine.

engine temp acts as expected with no thermostat.

at idle, a constant stream of bubbles in the radiator overflow bottle. tried another radiator cap, no change.

i suspect a blockage to the thermostat AND a headgasket failure?

?

[rex-leggy]

i believe bubbles in overflow = bad . are you able to do a leak down test?

compression might not bring up a headgasket failure

[Joker]

hehe you said sausage

[subieboy]

 JoKer said:

hehe you said sausage

hehehe trust you to mention it 1st... ;D

[kamineko]

mmm rust.. i'll have to take a pic of it

[vr4ex]

Id bypass the heater core all together and see what happens. you may find that the core (even tho its been flushed) may not be allowing enough water to flow through it to heat the thermostat.