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TR2/3/3A TR3 running HOT

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Got the head reinstalled and every thing back together. Fired her up and ..... still HOT. Burped the system clear. Backed flushed the entire system and no better. I ended up closing the heater valve while we were in Walnut Creek (25 miles away) and on the drive back home the temp stayed at about 200+, Ambient air about 60 degrees. The top tank is 200 degrees bottom tank 115 degrees water flow has got to be the culprit. Next will be remove the rad and have a flow test done. Can that be done with the rad in the car? Would be nice to not remove it.
 
I think my Wife found the problem ! She thought that it could be a loose nut behind the steering wheel! (she might be right)
 
tinman58 said:
I think my Wife found the problem ! She thought that it could be a loose nut behind the steering wheel! (she might be right)
Click to expand...

LOL. I had the read this twice to get it (it's Monday).

I feel your pain. I'm also facing the overheating demon, but only when stopped and in slow-and-go traffic. It was that way from day one (after a complete ground-up restoration). It must be more frustrating to have it suddenly occur in what was previously a normal running engine.

However, I'm sure you'll find a fix and share your solution with the group.

Just a thought: Did you recently install a six-bladed water pump? I read somewhere that, in some cases, they circulate the water too quickly through the radiator to properly cool the engine.
 
It was the same 4 blade water pump. I belive that maybe something crawled in and died in the raditor while it was on the side yard. But so far no evidence of dead critter being flushed out.
 
No doubt you have reviewed what work you did just before the overheating problem. If you itemize them here, along with the timeframe between the work and when you first experienced the overheating, there may be a clue someone will pick up on.
 
My bet is the wrong thermostat. I posted on this sight a year ago about a similar problem. Someone posted that the newer style thermostat will cause an overheating problem. It allows the water to bypass the radiator while the engine heats up. Then the engine gets hot but because of the bypass the thermostat is below temp it will not open. Thus the over heating engine.
Replace with the proper thermostat or block off the bypass hose.
 
tinman58 said:
I think my Wife found the problem ! She thought that it could be a loose nut behind the steering wheel! (she might be right)
Click to expand...

My wife thinks my problems stem from a dead short between the steering wheel and the ground.
 
lol
 
I have closed off the heater valve and the temp stays a little cooler.
But not cool enough. This weekend I will remove the front apron and rad. Remove the water pump again and try to find what is blocking thw water flow. Last night I took a drive and when I got home the top tank was in the 220 range and the bottom tank was about 115 degrees.
 
tinman58 said:
I got home the top tank was in the 220 range and the bottom tank was about 115 degrees.
Click to expand...


Dan:

<span style="font-weight: bold">105 degree F temp drop!!!!!</span> I don't think so. :nonod:

How are you measuring that temp? I ask because the temp. drop you state is unrealistic. Generally one of these old TR radiators will give a 10-15 degree F drop, MAX. A really good design, modern aluminum rad. will dump 25 - 30 degrees Max.

I just dug out my notes.
During the summer, we did some heat runs on the Grey Lady's engine. With a refurbished original TR3A rad (with the crank hole) and standard fan I was getting 205 at the top header and 188 - 190 at the bottom using an infrared thermometer. I marked three places on the top and bottom headers and averaged the temperatures. Engine was at idle (approx. 950 rpm), with an ambient temp of 85F.
 
angelfj said:
tinman58 said:
I got home the top tank was in the 220 range and the bottom tank was about 115 degrees.
Click to expand...

<span style="font-weight: bold">105 degree F temp drop!!!!!</span> I don't think so...
Click to expand...

Actually, that could very well occur if the radiator is truly blocked. Not a temp 'drop' per se, just lower rad coolant sitting there slowing warming while the head gets wicked hot.

If that is the case I would think some expermentation with a garden hose would possibly reveal the little or no flow thru the radiator.

Don't surgeons count the sponges after an operation?

Are you missing any shop rags?
 
I will take notes next time and not from my memory. But those numbers are pretty close . I suspect a blockage of some kind. I am useing a infrared heat gun. I just went out and ran the car for awhile and checked the heat rise. The top tank at 201 lower tank 152, The electric fan never came one (set at 190) Then the overflow blew out. I took the infra red heat gun and ran it back and forth across the face of the raditor and got measurements of 90 to 180. It looks like some of the rods are blocked. Any body experiance any thing similar?
 
I pulled the raditor out today. Also the water pump and the housing. I still can not find any restriction at all. I blew compressed air thru the heater pipe and got lots of air thru the block and head. I tried to backflush the rad. and no crud came out. I am going to take it to the rad shop tomorrow and I sure hope that they find a blockage.
 
The over heating problem is solved! What it was I am still not sure. I did find that the sensor for the new fan from Moss is bad, it closes at about 210 degrees. I got a adjustable one from Napa. 180-240 degrees. I reset the timing with the timing light at 12 btdc and the pinging is gone. (could it be the timing was way off?).
I went for a drive this morning and the temp never got above 185. The stat opened and the temp was very cool even at full throttle. I am going to go for a ride to see Paul (apbos) that will be a good freeway run and keep a eye on the temp. Thank you Guys for all the help and advice.
 
:banana: :banana: :banana: Alright Dan ! A nice ride through the Delta will be a good test. Let me know when you are headed my way.

Paul
 
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