Bleeding M50 coolant? No heat.

[Jon K]

Hey guys - due to my interesting engine layout I have to remove the radiator to get the power steering pump out. So to replace my pump, out came my radiator. Put the radiator back in, power steering is good, rocking. However, I am trying to bleed my coolant system which is the same as stock except with a different fan position, and I am not getting heat in the car.

The car doesn't seem to over heat or anything, but I am not sure I've got all the air out or whatever. I have no heat in the car which says to me that there is prob air in the heatercore.

Are M50s in E34s hard to bleed or anything? Maybe my aux pump doesn't work? I don't really care about not having heat, I just want all the air out.

Thanks guys

[russiankid]

Had the exact same issue. I let the car run for over an hour, no sign of heat. I put a long screw driver to the AUX pump to verify that it works. Since my car wasn't overheating, I took it for a spin. Once the RPM's went up, heat came into the cabin. I had to do this two times before I got all the air out. Give it a try, since you have a manual transmission you can just rev the engine.

[Jon K]

I spent like 10 mins tonight revving it. Nothing. I should just drive it. Meh.

[russiankid]

Did you squeeze the hoses after the valves and for the main feed for the pump? That helped out to my issue. Also, are you getting a steady flow of coolant from the bleed screw? I didn't get any fluid coming out until the air pocket in the heater core was pushed through.

[Jon K]

No not a steady flow of coolant from the bleed screw - in fact, nothing much comes out except steamy air. I didn't mess with it too much. I'll prob tweak around with it tomorrow. I'll squeeze some hoses. I am not even sure my heater valves work.

[russiankid]

You have the same issue I had. The upper and lower rad hoses would get hot, the feed hose for the heater would get hot, but the hoses after the valves were ice cold. You can tap the valves with a screwdriver. I remember reading that if they haven't been used in a while they can become stuck.

[Jon K]

Sweet I'll check it out tomorrow.

[russiankid]

You could also try pressurizing the system by blowing into the radiator. Make sure you don't have coolant everywhere. Trust me on that, coolant doesn't taste good.

[Dave M]

Jon, do you have the front end lifted? I ask as I've never had an ounce of trouble bleeding the system when I filled it with the front end raised. In fact, I rarely have to do much bleeding at all, just pour a bit more into the resevoir once its running.

I always do the initial fill through the upper rad hose (end that attaches to the rad) and fill the rad resevoir. Sometimes it'll burp a bit and allow more in.

Anyhow, just in case it'll help,

Dave

[Jon K]

Russia - I only run water - doesn't taste too bad

Dave - nah no front end lift - I dont like running the engine on jack stands - makes me nervous. But now that I think about it I could idle it on my driveway facing up as seen in my sig