fj40 overheating help

[another line]

I just purchased a 73 fj40 that has a new radiator, thermastat, and has had the system flushed. The head has also been pulled and checked out. The truck overheats in about 5 minutes. What is the next step in solving the problem. I was told the new radiator is out of a pinto, but not sure. Could someone please give me suggestions about the next step I should take in solving the problem?

Thanks

 

[Bret]

More info?? What motor?, top hose get hot? bottom hose collapse? new water pump? What temp gauge? been burped (get the air out)?

 

[3_puppies]

More info?? What motor?, top hose get hot? bottom hose collapse? new water pump? What temp gauge? been burped (get the air out)?

X2....5 minutes to overheating?? are you using methanol race gas?

 

[another line]

More info?? What motor?, top hose get hot? bottom hose collapse? new water pump? What temp gauge? been burped (get the air out)?

2F motor,original temp gauge, dont know about being burped, just picked it up today. What is my next move?

Thank you for the response!

 

[FF LC FREAK]

Still more info needed. How did you determine it was overheating? Stock gauge? Mechanical gauge? Symptoms? Heck, it takes at least 5 minutes for mine to warm up to normal operating temps.

 

[cruiserbrett]

A pinto radiator? as in a 2.3L pinto? maybe it doesnt have enough cooling capacity????

5 minutes suggests other issues:

have you checked timing?
belts tight?
waterpump good?
coolant passages clear?
headgasket installed properly?
fan moves air through radiator adequately?
air through fan is warm/hot?
finally, check the thermostat in a pot of hot water, slowly bringing temp up and note opening of t-stat temp with a thermometer.

 

[cjgoode]

I would get one of the radiator caps with the built in temperature gauge. Cheap and takes a second to install, but it only works if the thermostat is opening and the coolant pumping through the system. I would not think it could overheat in 5 minutes but gauge could be bad and slowly creeps up over 5 minutes. Above are good suggestions especially checking the hoses, another easy cheap way to check without taking stuff apart. You can also run it without the radiator cap and watch to see if the coolant is flowing, it is pumped back into the top, so it will be obvious if it is flowing through your system or not. But will no start flowing till the thermostat opens and water pump must be working. But do not take it off if you engine is hot and the radiator cap is hot.

 

[D'Animal]

You have air in the coolant system or you water pump is not working.

Start the rig with the thermostat cap off.

Turn on all of you heaters (both ?) to maximum heat. Start truck and add coolant fluid to appropriate level.

It will "burp" when the thermostat opens and when the air comes out of the heater lines. Keep adding coolant.

Make sure you fan is turning.

 

[FJ40 TOOLMAN]

Get a airlift from Uview check their web site.

 

[M5driver]

All the above is good advice. After you have checked everything else, if you still have the problem, don't forget to check the fan clutch. It's an insidious sort of failure, but a new viscous coupling can make all the difference. It took care of the heating problem on my Malawi Blue Mule.