1. Home
  2. SAAB Cars Forum
  3. c900 heater core bubble???

c900 heater core bubble???

I replaced the thermostat in my '86 900, and apparently I have a bubble in the heater core. The thermostat gets to a nice termperature, but the heat isn't coming in by me. I'm not seeing the bleeder valve I expected to see up in that area on or near the firewall, does someone have a procedure they could point me to?

I used Grunff's suggestion of opening the bleeder nipple on the thermostat housing, but I'm failing to see how that, being lower than the heater core, is going to help. What am I doing wrong?

On a side-note, googling for "saab coolant nipple" gives some interesting results.

Dave "Made you look..." Hinz

Reply to
Dave Hinz
Loading thread data ...

thermostat

Only proc I have is to *slowly* refill expansion tank with the engine off and thermostat bleed nipple open until coolant leaves the nipple. that's always seemed to work on 900s. Only suggestion is to try what I have to do on my Subies: run engine up to full operating temp, put heater full on, park facing up the steepest hill you can find (I've got a handy 1 in 3 road on the farm!) make sure it can't roll away and repeat the bleed procedure. It's always worked so far. If that doesn't work, all I can suggest is join your heater hoses together, flush the heater core and see if it's blocked. (Oh joy!) Cheers

Reply to
hippo

I've usually managed to clear it by opening the thermostat bleed nipple and revving the engine - it's the revving that does it.

There was one time when I just couldn't clear an airlock, so I pre-filled the heater core by connecting one end to a garden hose and flushing through at high flow. That worked.

Reply to
Grunff

I'll try it again. Maybe I didn't have it warm enough and the thermostat to the heater core was closed; sometimes I don't think these things all the way through, and sometimes I overanalyze them and trip myself up.

What is a 1-in-3 road? I've never heard that term before, but I do have

30 acres of land with hills. Is this a "slope of 3:1 ratio"? I've got that (on my 200 meter driveway in 2 spots).

I noticed a tee-fitting right on one of those hoses for flushing, so maybe that's not a bad idea if this doesn't work. Can I borrow your road?

Dave

Reply to
Dave Hinz

Ah. Didn't rev, because I was in the garage and didn't have a hose on the end of the bleeder. Seems like we're back to the c900 clutch bleeding conversation all over again.

I'll get heat. It had warm before I replaced the thermostat which was stuck open, so I know the heater core is good. Now, it has warm-ish, and I *know* a c900 heater can pump out real heat. We'll get there.

Thanks again Dave

Reply to
Dave Hinz

Yes - sorry, it's my English heritage...

Any time you're in Australia, you're welcome! Cheers

Reply to
hippo

Don't apologize for my ignorance of your language, please.

Same for you, and Wisconsin.

Dave

Reply to
Dave Hinz

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.