» Site Navigation | | » Recent Threads | | looove 04-16-2024 01:18 PM 04-16-2024 01:18 PM 0 Replies, 1,861 Views | | | | | | 09-15-2009, 04:41 PM | #1 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | M44 overheating Replaced the thermostat, new radiator, water pump, fan comes on when temp at 12, then shuts off, temp rises toward red. I had heater on high, bled air, but the overheat conditon continues. Top hose is hot and hard, so shut off and let cool, then refill a little, bleed, start again. 6 times. no leaks, no water at exhaust, don't know where it goes. When is the fan supposed to come on? When at low, when at high? cyl 1 206 psi 2 201 psi 3 207 psi 4 207 psi What is cause of this ? HELP!!! | | | 09-15-2009, 05:57 PM | #2 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | Thermostat installed backwards. Sounds like you're not bleeding it properly. | | | 09-15-2009, 06:05 PM | #3 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | CJ, Impossible! the thermostat is built into the houseing, It is not separate, you buy & install the "assembly". When and how does the fan operate? High & low? | | | 09-15-2009, 06:11 PM | #4 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | Woke up this am, had to refill about 16 oz. Idled and reved to 2500 rpm, went to 12 and stayed 5 min. I shut it off. Will start in 2 hr to see. Also, this time the fan did not come on at all so I shut it off. Now what? | | | 09-15-2009, 06:14 PM | #5 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | Low speed fan is triggered by temp sensor, high speed triggered by A/C. How did you go about bleeding the system? | | | 09-15-2009, 06:29 PM | #6 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | I have a manual and followed the directions section 170. A bleed screw is next to cap. Filled to half, put heat on, turn ignition on. then fill. Today is 8th refill i think. | | | 09-15-2009, 06:32 PM | #7 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | I have a new temp switch, I just went and started engine, then hit A/C and fan came on. Turned off A/C, no fan. So How do I low speed on. Thanks, in advance. | | | 09-15-2009, 06:34 PM | #8 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | Could maybe the wires in plug made in wrong position? | | | 09-15-2009, 06:35 PM | #9 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | You might be able to trigger the low speed by unplugging the sensor and jumping the pins in the connector. | | | 09-15-2009, 06:38 PM | #10 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | The fan shouldn't really cause the car to overheat though if everything else is working properly. When you turn the car on and it warms up, does the needle just keep rising? Are you getting warm air from the heater? I think you might have an air bubble trapped in your radiator. | | | 09-15-2009, 06:44 PM | #11 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | I unplugged the switch, hooked my test pencil light to ground on engine, in the plug are three wire posts, when I tried all 3 one of them turned on the high fan. Plastic Plug is heat deteriating. All three posts fell out. | | | 09-15-2009, 06:50 PM | #12 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | You might have a bad relay. couldn't hurt to check all of the fuses and relays, but the fact that the connectors are deteriorating sounds like a likely culprit. Also FWIW, I had a hairline crack in my radiator right next to the expansion tank. I couldn't see coolant leaking because it would evaporate on the hot radiator leaving no visible steam or moisture. You might try pressure testing your radiator. Last edited by cooljess76; 09-15-2009 at 06:52 PM. | | | 09-15-2009, 06:59 PM | #13 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | Could a head gasket be the overheat prob? I just went out and checked the coolant. is for first time at top. Brown wire with white is the one that is starting fan. Will the manual tell me if that is high or low? | | | 09-15-2009, 07:04 PM | #14 | NOBODY F's with the Jesus Join Date: Oct 2006 Location: Ventura California Posts: 7,824 | Absolutely, but lets not go there yet. Unless you see signs of a blown head gasket, try to stay optimistic. Any smoke? coolant in the oil, oil in the coolant, sweet smell coming from exhaust? You never answered if you were getting warm air from the heater. Also, expansion level rises when the coolant heats up, hence expansion. As for wires, I'm not sure. | | | 09-15-2009, 07:24 PM | #15 | Senior Member Join Date: Apr 2009 Location: TampaBay, Florida Posts: 104 | 1. Black w/grey jumper wire to brown, high fan runs 2. Black w/green jumper to brown, nothing or to engine grd. nada Low fan must be bad? | | | | | Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | | Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off | | | |