Author Topic: M42 cooling isue (Read 3098 times)

curtis · « **on:** February 26, 2007, 11:59:43 PM »

i replaced the waterpump, thermostat, and fan clutch within the past month and my car still has this issue. the heater doesnt work, but will when i rev the engine. i tried bleeding the car several times, and the heater starts to work when i bleed it. then after a while, the heater looses the heat. the temp gauge is between the 1/4 and 1/2 mark, but if i let it idle for really long periods of time, the engine will get hot, but very slowly, and as soon as i take off or rev the engine it will cool down. i was recommended to flush the radiator, and the heater core, but what do you guys suggest? im just new to the m42 and trying to figure out my car. also, whats the rev limiter set at in these cars? mine revs to 7k and the previous owner told me it had a AC chip, but i was skeptical.

thanks,
curtis

melloh · « **Reply #1 on:** February 27, 2007, 11:39:55 PM »

Curious.. I'm having similar issues w/ my cooling system. Keep us updated on your events!!!

Re: the chip. You probably do have some form of aftermarket chip b/c stock will limit you to redline (around 6500).

romkasponka · « **Reply #2 on:** February 28, 2007, 01:29:16 AM »

What do you think about water valve nr. 7 ?http://www.realoem.com/bmw/showparts.do?model=AF91&mospid=47256&btnr=64_0523&hg=64&fg=15

curtis · « **Reply #3 on:** February 28, 2007, 11:28:29 PM »

is there any way to check the water valve?

vatos_p · « **Reply #4 on:** March 01, 2007, 02:35:09 AM »

I Had The Same Problem , And The Water Valve Was The Problem , But You Will Also Need To Check The Temperature Button , If It Sends The Signal To The Water Valve To Open , The Water Valve Is Electrothermostat , And When You Open It , It Lets Hot Water To Get Through , But While The Temp Is Rising , If You Want Less Temp , It Closes ... Mine Was Also Leaking Water Into The Car , And When I Discovered It I Gone Mad... I Also Changed The Water Radiator , Just In Case And The Problem Is Gone... ( I Was Told That The Water Valve Goes Wrong Several Times Over The Years Cause Of The Salt In The Water Makes The Moving Parts Stick ( Because All The Summer It Is Closed And The Water In There Is Stable.. )... To Prevent This , All The Year , From Time To Time Open The Heater ( Even In The Summer , So Water Can Pass And Clean The Valve...

Hope It Helps...

Alpine003 · « **Reply #5 on:** March 01, 2007, 09:30:11 AM »

Quote from: curtis;20340

is there any way to check the water valve?

Just disconnect both upper and lower heater hoses from the engine side firewall. Take a water hose and attach it to the lower port and see if the water flows ou the top port when you have the car in the on position with the heater running.

Also make sure your heater hoses aren't mixed up as well.

I had a similiar problem which turned out to be a clogged heater core. I just took some compressed air and ran it through which fixed it luckily.