Too Hot! help!

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Joined
Mar 28, 2014
Messages
53
Location
Guatemala
Website
www.junajpu.com
Hi! I have been reading the threads, and yet......
It's a 1974 FJ40 4 coil radiator, new exhaust sytem with a thermal wrap, rebuilt alternator, new water pump.... This is a fairly new situation. hence, the above work.
It heats up very quickly, and when if I am standing still in traffic, the temp gage goes past the half mark, then goes back down to 1/4 mark (normal in my rig) when I am driving. none the less- the temperature inside the cabin remains unbearable after 20 minutes of driving! Worse on the drivers side than the passenger as the exhust (even with the termal wrap)runs under drivers side.
It drives much hotter on the coast, then it does when I am home in the mountains.
Any suggestions?
Thanks in advance wonderful men! (yes, you are ALL men. I am most lkely the only woman on this forum! hahahahaa gear-head!)
oh yeah, and while I ahve your attenshun, any suggestions for a new carb? Txs!! : )
 
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Have you checked the coolant level? The heating up past the half mark and then going back down to 1/4 while driving, sounds like a low coolant problem. The cab in my 40 gets warm as well but I'm going to try some dynamat in the spring. Hopefully that will help with the heat. There are several women on the forum as well. Good luck and post some pictures of your 40.
 
Have you checked the coolant level? The heating up past the half mark and then going back down to 1/4 while driving, sounds like a low coolant problem. The cab in my 40 gets warm as well but I'm going to try some dynamat in the spring. Hopefully that will help with the heat. There are several women on the forum as well. Good luck and post some pictures of your 40.
Coolant is fine.. topped off...... Thanks! will post pics!
 
So you think the 1.5F engine runs hotter down by the ocean? What are the outside air temperature differences in your mountains versus your coast. What is the change in elevation?

Pictured below is a 1974 factory Aisan carb that came on USA FJ40’s. If you have the same carb you should rebuild it. Also, you might try slightly larger jets.
7E13A282-4D85-4D4B-94E3-24EBC616E23E.jpeg
 
there's a lot more females on here than you'd think.

has there been any maintenance on the cooling system?
thermostat issue, plugged passages in the block, removing rear drain would tell that, water pump?
does your rig have a heater? shutoff working?
 
Also check the advance mechanism in your distributor, and the ignition timing. If the distributor vent system is not working, it is fairly common for the advance mechanism to rust up and not function, and retarded ignition timing will make it heat up in a hurry.
 
Thank you Thank you Thank you....! You guys are FANTASTIC!!!!
I'm actually going to have to take it to a mechanic to check out your suggestions theadvance mechanisim. I put in eectronic pertronix points a while back.
I will do the tilt and burp myself first, to see if that helps.
We are 1538 meters above Sea level. about 5000 feet.
NO heater, no cooling- don't know thermostat temp.
Here are pics:
THANK you ! Muchas Gracias!!!!!
(It's muddy still from the beach- dirt road+rainy season= Mucho mud everywhere!)
IMG_1090.JPG


IMG_1091.JPG
 
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So you think the 1.5F engine runs hotter down by the ocean? What are the outside air temperature differences in your mountains versus your coast. What is the change in elevation?

Pictured below is a 1974 factory Aisan carb that came on USA FJ40’s. If you have the same carb you should rebuild it. Also, you might try slightly larger jets.
View attachment 1568142
Temp difference is about 20 degrees or more.... say 70's to 90's
here is my carb which was rebuilt already in May 2015!
Elevation where I am mostly (Antigua Guatemala) is 5000 feet. I surf, so I go to the beach almost every weekend... and MELT.

IMG_1085.JPG
 
Another possibility, the engine block could be so gunked up that coolant cannot get to areas that need it. Flush the block and you may be surprised.
 
5,000 feet elevation should not be an issue. looks like the gas level in the carb bowl is low.
interesting that there is no brake booster.
very nice looking rig.

another thought is there the proper mixture of coolant to water. even tho it won't freeze by you, it still needs a mixture of coolant to aid in cooling.

just looking at the 1 engine picture, the bypass hose is capped off. it goes from the water pump to the neck above the thermostat.
 
Very nice rig! Just a thought, I'd buy a temp gauge at the auto supply store that shows the actual temp. of the coolant and install that. A very simple job. Sometimes the old factory gauge can be iffy.
 
Thank you Thank you Thank you....! You guys are FANTASTIC!!!!
I'm actually going to have to take it to a mechanic to check out your suggestions theadvance mechanisim. I put in eectronic pertronix points a while back.
I will do the tilt and burp myself first, to see if that helps.
We are 1538 meters above Sea level. about 5000 feet.
NO heater, no cooling- don't know thermostat temp.
Here are pics:
THANK you ! Muchas Gracias!!!!!
(It's muddy still from the beach- dirt road+rainy season= Mucho mud everywhere!)
View attachment 1568197

View attachment 1568200
Nice color--maybe "Old Pumpkin"?
 
5,000 feet elevation should not be an issue. looks like the gas level in the carb bowl is low.
interesting that there is no brake booster.
very nice looking rig.

another thought is there the proper mixture of coolant to water. even tho it won't freeze by you, it still needs a mixture of coolant to aid in cooling.

just looking at the 1 engine picture, the bypass hose is capped off. it goes from the water pump to the neck above the thermostat.
This may be the key, here--no bypass hose--may explain why the thing heats fast, then cools down--did it do this before??
 
no radiator overflow reservoir ?
 
Since this has had a new water pump put on it probably dose have an air bubble try running it with the radiator cap off and see if it burbs out any air or maybe flush the radiator and replace the thermostat.
 

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