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Wedge TR7 instantly overheats!

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sammyb

Luke Skywalker
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One day the TR7 was fine...then after about two weeks of sitting, I was trying to tune the carbs, and I noticed the temp gauge pegged at HOT.

I replaced the thermostat, which appeared to be near new. Still heats up in under a minute.

Sound like a dead water pump to you all?
 
either a dead water pump, or you have air trapped in the system are my first two guesses. if its not that, then you have must have oatmeal in your radiator /ubbthreads/images/graemlins/wink.gif

edit: also check to make sure your temp sending unit and guage arent faulty before you pull off the water pump!
 
Sometimes you can tell what is going on by (cautiously) feeling the big radiator hoses. The normal sequence is that the top hose gets no more than warm until the tstat opens... then the top hose quickly gets hot. The bottom hose remains fairly cold until the the tstat opens, then it slowly warms up.

"Heats up in under a minute" is real quick -- I would suspect a sending unit or (less likely) the gauge.
 
My TR-7 Spider runs quite cool, generally below the middle bar. It also takes a bit of time to warm up. I agree - one minute sounds much too fast for accuracy. Feel the hoses - they'll be wicked hot if you're actually overheating immediately.

Best wishes,

Jeff
 
I vote with geo, nothing can actually GET really hot that fast(barring fireworks). Bad sender/electrical gremlin in the circut.Dont overlook the fuses, corrision on the terminals is a problem on the 7's........
MD(mad dog)
 
Borrowed my friend's pyrometer, and it looks like the sending unit is fried. The gauge reads H, but the thermostat housing/sending unit reads an actual 90 degrees!
 
Hope you got the right answer there. One of the easy solutions, at least a lot easier than a water pump. /ubbthreads/images/graemlins/thumbsup.gif Since you've got the part of the system that's the problem, before you get a new sending unit, you may want to check the continuity on the wire. Most of the gauges read to the far right when grounded (I know the fuel gauge will read full when the wires to the gauge from the sending unit are grounded). You never know...the wire may have rubbed somewhere and is being grounded out. (Imagine that...an LBC with too many grounds! /ubbthreads/images/graemlins/devilgrin.gif)
 
The only behavior that has me thinking it's not the wires grounding-out is that it "sweeps" up on start-up, but as soon as the car begins to warm, if you turn it off and turn the key on again, the gauge will "flick" (immediately, with no sweep) to hot.

So I'm guessing the sender, but I can always throw a multimeter on it.
 
Hey, Sammy, is that your wife's car that gets to sit outside in the tent, while all the collector LBCs and Corvettes get the garage space? How does that work (I need some hints for convincing my wife to do the same thing)? /ubbthreads/images/graemlins/confused.gif
 
My wife's car isn't in the pic. We have a '98 Olds Intrigue and a '98 Expedition (that we received free as a hand-me-down from my in-laws.)

Right now, I have 4 cars in the garage ('89 Corvette is where the TR7 is in this pic.) TR7 is outside in the portable garage, and then my '86 Dodge sits outside. Usually, there's one car somewhere else -- like right now, my 2002 Corvette is in the shop (where it spends most of the time!) So the Dodge is in the garage.

Honestly, I hate having ANY cars outside, especially daily drivers. I can't stand walking in the rain to put my kids in the car, but I'm saddled with no room to expand. At some point in the future, I'm going to find a small warehouse space locally to put a few cars. My inlaws own a warehouse in Hoquiam, WA, and they keep a couple cars down there (and the Dodge was there for 5 years.) But it's an hour away, which defeats the purpose for me. (It's 90 min away from my inlaw's house, but don't get me started! /ubbthreads/images/graemlins/crazyeyes.gif)


And dare I say...I'm planning on selling the TR7 to one of my best friends. /ubbthreads/images/graemlins/cryin.gif I promised to sell him the car if he wanted it for what I have into it. That's one of the reasons I need to get this temp thing under control, because I want the vehicle to be in perfect working order, so he can just drive it and have fun.
 
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