I just bought this truck. It's a 1971 Kaiser with a multifuel diesel engine . The first time we took it for a ride I noticed that after about 5 miles t he temperature was climbing up towards 220 degrees. We brought it back to the house and checked the coolant and found it to be topped off and hot. H owever I felt the radiator core starting from the top and working my way do wn. For about the first 4 inches or so the core was warm but as I moved tow ards the bottom it gradually got cooler. The bottom area was ice cold. I wa s under the impression that the only thing that would cause this was a plug ged core however in speaking with some people it was suggested to me that t he thermostat may not be opening. This truck has an optional military heate r kit mounted in the engine compartment and both hoses to it are hot, so I would think that means that the thermostat is opening. Is that correct? Wha t would be a proper way to troubleshoot this problem? Thanks, Lenny
The heater taps in before the thermostat and is currently acting as your radiator.
I would say it's a stuck thermostat. Grab an IR thermometer and check both sides of the housing when it's warmed up. If the engine side is up to temp and the other side isn't you have a bad thermostat.
Or just pull it out and toss it into boiling water.
I drove one of those trucks almost every day in 1964 when I was in Vietnam. They were fun to drive. Every morning required letting the engine run for five minutes so the aircompressor could pump up the air tank for the brakes.
On Tuesday, April 12, 2016 at 4:31:29 PM UTC-4, snipped-for-privacy@gmail.com wrot e:
ne. The first time we took it for a ride I noticed that after about 5 miles the temperature was climbing up towards 220 degrees. We brought it back to the house and checked the coolant and found it to be topped off and hot. However I felt the radiator core starting from the top and working my way down. For about the first 4 inches or so the core was warm but as I moved t owards the bottom it gradually got cooler. The bottom area was ice cold. I was under the impression that the only thing that would cause this was a pl ugged core however in speaking with some people it was suggested to me that the thermostat may not be opening. This truck has an optional military hea ter kit mounted in the engine compartment and both hoses to it are hot, so I would think that means that the thermostat is opening. Is that correct? W hat would be a proper way to troubleshoot this problem? Thanks, Lenny
Hey guys I drained about 4 gallons out of the radiator and then I pulled the hos es and the small housing that holds the thermostat. The water is pretty rus ty so I won't reuse the coolant. After I'm done I'll give the system a good flush, fill it with water only, and see if I've addressed the problem. And if so then I'll drain it again and fill with antifreeze. But in the meanti me, the thermostat is really stuck in the housing. I tried gently prying wi th the tip of a knife but no joy there. I suppose that I could heat the hou sing and thermostat as one unit in a large enough pot to do the water test but I'd really rather have the thermostat out of the housing to do it. I'm afraid though that I will destroy it trying to get it out. If this happens naturally I could replace the thermostat but then I wouldn't know if it was in fact the cause of the problem until I put it all back together and try it out. Does anyone have any ideas for separating the two? Thanks, Lenny
On Saturday, April 16, 2016 at 1:16:40 PM UTC-5, snipped-for-privacy@gmail.com wro te:
ote:
gine. The first time we took it for a ride I noticed that after about 5 mil es the temperature was climbing up towards 220 degrees. We brought it bac k to the house and checked the coolant and found it to be topped off and ho t. However I felt the radiator core starting from the top and working my wa y down. For about the first 4 inches or so the core was warm but as I moved towards the bottom it gradually got cooler. The bottom area was ice cold. I was under the impression that the only thing that would cause this was a plugged core however in speaking with some people it was suggested to me th at the thermostat may not be opening. This truck has an optional military h eater kit mounted in the engine compartment and both hoses to it are hot, s o I would think that means that the thermostat is opening. Is that correct? What would be a proper way to troubleshoot this problem? Thanks, Lenny
oses and the small housing that holds the thermostat. The water is pretty r usty so I won't reuse the coolant. After I'm done I'll give the system a go od flush, fill it with water only, and see if I've addressed the problem. A nd if so then I'll drain it again and fill with antifreeze. But in the mean time, the thermostat is really stuck in the housing. I tried gently prying with the tip of a knife but no joy there. I suppose that I could heat the h ousing and thermostat as one unit in a large enough pot to do the water tes t but I'd really rather have the thermostat out of the housing to do it. I' m afraid though that I will destroy it trying to get it out. If this happen s naturally I could replace the thermostat but then I wouldn't know if it w as in fact the cause of the problem until I put it all back together and tr y it out. Does anyone have any ideas for separating the two? Thanks, Lenny
Parts for old Military vehicles can be expensive. Try squirting some automa tic transmission fluid and let it soak a long while, and tap around the are a with a hammer, that might loosen it up.
I bet strongly that the thermostat isn't the only thing that is bad.
You might risk doing the acid flush. Chances are good that everything that was marginal before fails during the acid flush though, so be prepared to rebuild the radiator and possibly replace a head gasket if you do.
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