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RedTR3

RedTR3

Jedi Trainee
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My coolant bypass hose blew and the car overheated. It stalled like the head gasket had blown - but after cooling down the car ran great.

Now a week later the car still runs good but runs 20 degrees hotter than before after 20 minutes of running. I am not losing any coolant and the oil has no traces of coolant.

Any ideas as to why I am now running hot? Can the head gasket be blown causing overheating even if I am not losing coolant?
 
Are you absolutely sure you got all the air out of the system? I don't necessarily know TR3s well, but yif you didn't turn the heater on full bore, and ran it until the thermostat opened and then topped it off, that could easily be the problem.

Jody
 
You might also try to burp it by squeezing the lower radiator hose with the cap off and cold. Squeeze the hose a few times and try to push trapped air out. Used to have to do this to the race car and it worked.
 
I know with the TR6 you need an overflow bottle with some fluid in it to get out all the air. Turn the heater on and let the car get up to temp and then shut it off and let cool. This should burp out the air, and then it sucks back the needed fluid from the overflow to fill the system. You may need to do it a couple of times. I don't know about the TR3 though, mine is not ready for the road. I'm not even sure if the 3 came with an overflow bottle. I would like to know if it did though.
 
My guess is that the engine is fine, but overheating it changed the calibration on the temperature gauge. I've had the exact same thing happen.

Another possibility is that it damaged the thermostat.

The TR3 motor is not particularly susceptible to air bubble problems, so I doubt it's that. Could possibly be a head gasket leak, but if so, you should notice that you can't keep the radiator filled normally (eg about 1/3 up in the filler neck).

Any radiator shop can do a simple test to reveal a head gasket leak. Mine charged me $18 last time I had them do it. Then I found the tool on eBay for $25, so now I do my own. For some odd reason, they are known as "block testers"
https://cgi.ebay.com/Engine-Block-Leak-tester-cylinder-head-radiator-/310242005517

Edit: There is also a (consumable) chemical required, which I just noticed is not included in the auction I linked to above.
 
Yea, What they said.

If it got really hot the guage could be wonky, or the sender.

Time to check the guage against something known,

either boiling water, or an IR thermometer.
 
Hi Red one thing you might check is that people sometimes place objects in that by pass hoes to help cool the engine down and they actually do work. I knew a guy once who used a plumbing plug with a 3/16 hole drilled in it to only let a set amount of water pass by. I choose to use the thermostat that slides into the bypass hole and slows the flow that way because it always sounded to me like the plug would blow out and the temp would rise 20 degrees.
Steve
 
Any recommendations for an outfit to repair/recalibrate the mechanical temperature gauge? I have heard of Nisonger, are there any others to consider?

Thanks
 
Mo-Ma is considered the best :
MO-MA
1321 2nd St NW
Albuquerque, NM 87102
(505) 766-6661
momanm@aol.com

They do gauges for a lot of Pebble Beach cars, but they can get behind and be slow sometimes. There is also:

West Valley Auto Electronics (was WV Instrument Specialists)
19314 Vanowen St.
Reseda, CA 91335
818-758-9500
https://www.westvalleyautoelectronics.com

Lots of TR folk use them, never heard a complaint.

These folks used to be very well regarded, but I've not heard anyone using them recently:
North Hollywood Speedometer & Clock Co.
6111 Lankershim Blvd.
North Hollywood, CA 91606
Phone 818-761-5136
Fax 818-761-4857
https://www.nhspeedometer.com/

FWIW, Mr. Nisonger sold out a few years back, and there were apparently some problems (and unhappy customers) right after the change. But most folks seem happy with them these days.
 
I'm sure there are others but Nisonger did mine. Cost $135 though that might have changed. It came back looking like new, including new mounting pipe clips and a new grommet. Very happy with their service.

Tinkerman
 
Since your in CA.Use the folks Randall mentioned. Might as well not ship it all over the country
 
I am not sure what kind of thermostat you are running, but before I would pull the temp gauge and send it out, I would check out the thermostat. If it is not one of the sleeved ones, I would get one and see what the gauge reads. My experience has been that without the sleeved thermostat the water travels to fast around the head and raises the temp some. How hot does your gauge read, 190? Usually when you put in the stock thermostat they run at about + or - 180.
Steve
 
The bypass hose blew on my TR3 not so long ago and the temp gauge did not register the temperature increase! When I tested the gauge in boiling water it did register an increase. Apparently I had been driving it like that for awhile as the coolant level was down quite a few litres. I'm curious to know whether your gauge let you know that the hose had failed? I am running a plug in the bypass as recommended in Bill Shaller's book on TR's instead of the full skirt thermostat. When I put the new hose on I wrapped it with an elastic type high pressure tape just in case. My engine didn't suffer any ill affects either. These engines are tough.
 
Steve wrote above about a pipe thread in the casting for the by-pass hose where there was a small hole drill in the plug. I did that on my 1958 TR3A in 1989 (as per Ken Gillanders and others) and about 2002, I took apart the by-pass hose and found that the 3/16" diameter hole had become blocked with some beige sandy powder with was caked in the hole and blocking it.
 
Karl, No, I had no warning the gauge started climbing rapidly but never pegged and the the engine died as I pulled over. No time to shut it down really. I too was running the drilled pipe fitting and I think that the stress of the fitting in the hose caused the hose to blow (the fiiting is a little larger than the hose ID and the area near the fitting is where the break occured.)

Actually, I am curious to know why the engine stalled if the head gasket is not blown.
 
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