225 Operating Temp???

I just bought a 1968 CJ5 with the Buick 225 and was wondering what the normal operating temperature should be. Since I have bought the Jeep I have replaced the instrument cluster so it now has a new temp guage and I have also bypassed the heater core. I started it up last night to see if it ran hot and the temp needle went to the end of the gauge within 5 minutes of driving it in my neighborhood. What are possibilites for the engine running so hot. The radiator is full of coolant.

Thanks

 

First take a qiuck look in the radiator, might be plugged up, Second thing I would do is check the thermostat, If you dont know the last time it was replaced , then I recommend replaing it just for your peace of mind. If it overheated that quickly then I suspect thermostat not opening. Good luck

 

The radiator seems new and inside looks very clean. The Jeep does not have a body lift or a fan shroud. I have a thermalcouple also to check the temperature, anyone know what would be too hot...around 250??? Looks like I am gonna check the thermostat out. Thank you very much for the help and hopefully this works. I will keep you guys posted. Thanks a lot.

 

mine runs right at the "good and green" bottom of my stock gauge even on 90* days here. it's a 180 therm. during winter it is pretty cold blooded but i didn't have it running most of the winter cause of the steering.

 

Ok so I played around with the Jeep. I noticed that within about 3 minutes of just idling the temp guage was showing between 80% and 90%, which seems way too fast. I unscrewed the radiator cap and observed the coolant and didn't see any movement at all. The top hose of the radiator was cold while the bottom was hot. I dipped a themalcouple in the fluid at the top of the radiator and it was not hot at all, room temp basically. I am assuming that the coolant is pushed through the thermostat to the top hose of the radiator and then it is cooled and then leaves the radiator at the bottom tube? Am I Right?? So it looks like my themostat would be bad then? Just wanted to get your guys' opinion again as I am just a newbie and trying to learn.

 

Sounds like a stuck thermostat to me...

How many of you run without a fan shroud btw?

 

no shroud, just the po's rubber flaps on the side of the rad.

 

shroud

 

no shroud, no overheat

 

Shroud you gotta be kiddin, the only early cj5 I have ever seen with a factory shroud was Patricks at Tellico this year, heck his cowl is totally different then my 71 model.

 

He should start making copy's to sell.

 

Wasn't there someone selling copies of that shroud on ebay a while back?

 

i've got the orig. fiberglass shroud on my 69. a littl chunk is missing where the po tried to route his version of power steering tho.

 

I'd be in line to buy one!

 

Does anyone know what could cause the thermostat to be stuck in a closed position?? I can't figure it out.

Put a new thermostat in today. Gonna check it out and see if it works tomorrow. What could be other posibilities, a bad water pump, blockages...???

Thanks again for all the help.

 

I've seen a 225 that always ran hot baffle alot of pros... turns out the PO had installed an even fire HEI-- The 3 cylinders that were firing at the wrong time caused that bank to overheat quickly.

Just an idea I thought I'd throw out there.

 

Sure...out of plaster of Paris .