740 Volvo Overheating problems

monroede

No mechanic or dealership has been able to resolve this problem. We have paid for replacement parts, busted hoses,themostats, just to name a few. I have 165,000 miles on this car. I know I might need a complete overhaul eventually. But I don't want to replace the transmission, engine, starter, another themostat (the current has been in this car for under one year)or the radiator when the problem may just be something that may cost under $150.00.

I was told by another volvo owner that there was a defect with early 90's Vovlo cars and some type of alloy seal that causes these types of cars to overheat. But the mechanics and the dealers in my area said that is not true. Yet they can't seem to resovle the problem.

This is what happens: After driving the cars for over an hour, if I am stuck in traffic or at a fast food drive thur window with my feet on the brake the cars starts to overheat. If i don't move and allow the car to run at about 50 miles an hour the car keeps on overheating then I have to pull off on the side of the run. This is dangerous. Therefore, I only use this car for short errands.

What is the connection between my brakes, the car overheating, driving slowly in traffic. I dare not to go into rush hour because the car will overheat. After waiting for about 30 minutes for the car to cool down and I can drive again. The other day this happened and I waited and waited for it to cool down and then I decided to put my feet on the gas and let the car troddle and then the needle moved from the danger zone.

I've gotten so that I don't trust mechanics because they are just taking my money and the problem is still there. This has been going on for over 3 years. Please help!!!!

thank You
Deborah

Mr_Shiftright

If you have already repaired the theromostat, electric cooling fan, and the radiator, all with no luck, then I would suspect, at this mileage, either a defective head gasket or a crack in the head that allows exhaust gases to seep into the cooling water (this is testable). Overheating at low speeds initially is often a sign of thermostat or electric cooling fan problems, whereas high speed overheat is more radiator related or water pump related. A head gasket or cracked head can cause overheating anytime, depending on engine temp and other conditions.

With this high mileage, it could even be a combination of many things...the car is near the end of its life, so I do understand your reluctance to put in large amounts of money.

Again, I'm presuming you have put in a new radiator core, new theromostat and new sensors for the cooling fan.

monroede

Thanks, Mr. Shiftright

I'll check into your suggestions, I appreciate your help.

lngtonge18

Sounds to me like your cooling fan sensor has gone kaput. It tells the cooling fans to turn on when the car gets too hot. I currently am having the same problem with my 91 Nissan Stanza. It's temperature stays normal as long as the car is moving or the AC is on (AC automatically turns on the fans). But if I sit in traffic for too long or at a drive-through with the AC off, it starts to overheat. The problem is the cooling fan sensor is not turning on the fans when the car gets hot. Another possible solution that is often overlooked is the relays controlling the fans. My VW had a problem overheating intermittently and I replaced the sensor controlling the fan, but it still continued to overheat. It turned out the relay was screwing up and not clicking on the fan. A simple $20 part that you can replace yourself. The relay failed at right about the same mileage you have on your car.