Hi, been doing the break in still. At about 450 miles.

I hve noticed that when i go out, temp gets to between 1/4 and 1/2 on the gauge.  If i sit any period of time or dnt keep moving, it creeps almost to half, the, sort of quickly Drops back to just a shade over 1/4.  This sort of back and forth is currently the norm.

In the old engine, i cant think of more than two or three times, it ever went over 1/4.

Tonight, i took it out,  same deal. Stayed between 1t4 and 1/2.  I cut through town, spoke to some one about 5 or 10 min then took off.  Really didnt pay attention to engine heat as it was doing what it had been.  To get home, i have to go up a pretty steep incline so i hv to kind of get on it to get into the gear to get up.   Got about half way up and it cut out.  I quickly put in neutral and started, but it died out when i put it in gear.   I happened tp look down, and gauge was at 3/4!   So i backed it down the hill, got permission to leave it a couole hours. Will go back when it cools off.  Have no idea if that will help.

It was over 90, about 15% humidity, if that even matters.  I cked anti freeze b4 going, it was full.  No leaks of any kind.

Any thoughts were this may be going?  Is thermostat bad,   im.just at a loss and not sure how to diagnos.  When it sputtered out, it was when i hit the gas to get a lower gear, like fuel just didnt get there.

I just sort of thought the higher 1/4 to 1/2 was durme to rebuild.

Any suggestions to begin to figure it out?

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A quick up date from above.  I let it cool, went bk, tried to start it.  Like not getting fuel.  I know its not out of gass.  Noticed fuel bowl at probly a quarter or shade less.   So i dropped a liyttle gas in carb.  Hoping to get things going so i can get it out pf ladys driveway.  Well. It tried to start. Then a litte fire broke out in carb.  I got it out very quickly.  Still noticed no lift in fuel bowl level.   So maybe this isnt all heat but fuel to engine.    What would you think if it now wont start.  Could there be a vapor lock.   I run the high test gas.   Could the overheat be related to no fuel?

Looks like you have a problem with the fuel pump. Check the amount of fuel coming out of the pump by loosenig the tube from pump to fuelfilter.

Well, i let it sit overnight, went to start this morning. Still no go.  Went tp the mechnic that lives down street who has been giving me theory and engine lessons on mechanics to help me drag it home.   He open hood, tinkereid w the carb.   I was in truck getting straps out, then i heard the engine turn over. It started!   He drove it home.    It was his assertion that the extreme heat of the day, at one time was 100, but 90 or so when i went out,  the heat built up during my conversatoin at idle.  A vapor lock situation occured.   He went on the explain it in some terms i coukd understand.  He felt i may need to re calibatre the choke spring as he felt it may be a little slow to react. But we left car idling for 15 minutes, no excessive heat build up,  ambient was about 75.   Bowl was filling up, running just fine.  So, feeling of looming disaster has been temp averted.  I also learned about and actually understpod mechanics of vapor lock,   at minimum, i got some education and can hopefully kno this if it happens again.   Thanks for comments and considerations.

Still working to end breakin period!  Probly gonna drive in mornings till the oppressive heat goess away, supposed to be over 100 todsy.


Very normal to go to 1/2 gauge ( is 200 degrees ) and then back to 1/4 -plus —( 180 degrees ) during normal use ( no harm at all ) from an idle period to driving again especially when very hot outside 

Anything over 1/2 gauge is starting to get too hot for any  longer period of  run time 

If you had the car idling when you were talking to someone ( not sure ?) that may have caused your heat build up on a very hot day ——so don’t do that 

The engine is producing more friction between moving parts during a brake in and that adds to some heat build up - watch oil use  during this time ( will be burning more than usual  as rings seat ) 

Check your point setting  and timing ( if you have points ) as timing  setting directly effects engine heat in cylinders and under hood 

Advanced timing will run  the engine cooler and retarded timing will run the engine hotter - run 5 - 8 degrees should be fine — but check it to know it’s right now 

Always check timing after you secure the dist hold down bolt to be sure it did not change while doing the tightening down part 

Always put your air cleaner on before you start the engine to prevent a carb fire 

You  could consider —insulating your metal fuel line from the fuel pump to the carb ( with aluminum foil or other insulation to reduce under hood temps on that tubing which may help with  a vapor lock condition in very hot weather 

Let me know what you find —-with you timing setting when you check it 

The engine is tight until it brakes in so these issues should improve with 5- 10,000 miles on the engine which to me is the break in period 

Avoid idling the engine a lot until you put some miles on the new engine 

All   your symptoms are a lack of fuel getting to the carb for some reason ( vapor lock -a clogged filter etc )  - so replace your fuel filter- if due — and check the metal fuel line filter inside the carb where the fuel line enters it for debris  

Let me know how you do 


first off the bat,,, temps here have dropped considerabley,, 80s.. and the car temp has held at a much better, lower level,, just barel over the 1/4 mark,, creeping to the 1/3 but hasnt been near the mid line since.  it starts just fine,, runs fine,, leads me to believe the heat was the primary contributing factor, but i have picked up some of the parts ot change the fuel filter.  i will be done with the 500 mile break in in a afew days, then take it on a litlte hour to two hour excursion to bozeman and back,, see how things go,,

my neighbor down street has basically cut out the old wiring, put in new or reattached where needed.  cleaned up engine bay,  put that aluminum cover on lines to protect as you suggested,,also, put protective sleeves on a couple other places where spark lines were close to gas, like near the accelerator pump,, for the reason you siad,, if a stray spark or lot of heat builds up,, and a little gas has gone astray.  he has educated my on other things engine wise,, and on my 73 eldo convert,, he got the ac running,, damnedest thing,, i had about four controllers behind the glvoe box, i had stashed, he did whatever he did, pulled good pieces off each, tested each,  replaced on a base unit, tested for what ever ohmage or amps or  whatever you test for on those things to be able to push those roads and little motors and gears aroudn, and damn if he didnt get aht thing running,, all teh speeds on the ac unit regulator work, auto, hi low, defrost,, heat cold,, took him three days, but he got it.. never looked at a manual,, he apparently has a  unique ability that he has acquired over time and a natural understanding of electrical and mechanical things... most of his career was in the fleet mechanic shop at Yellowstone NP,, fixing diesels, dump trucks, snow machimes, bull dozers,, just about any engine the park service has,,.so his knowlegde and willingness to show me and share has been hands on helpful. he explains what he is doing, why he does it, and while i can only absorb so much at my vintage age,, its a late education i am enjoying,,, i really think he likes these old rides..

i will forward a couple pictures of the engine as he has put on the protections etc,,  give you an idea of what it looks like, im sure as it should be,, no loose wires dangling around, all taped up and clean,, actually looks good!!  

You did not say you checked your  ignition timing  which might be some of your heat causing issues under the hood —so worth a check 

A clogged fuel filter will cause the engine fuel mixture  to —run lean —and cause higher temps in the engines cylinders 


What is the temperature rating on your thermostat? If it’s lower like a 160 degree you’re more likely to se more fluctuation on the gauge.  Also I think you’re better off getting an actual reading of the coolant temperature than going by the gauge,  if the sending unit was ever replaced it may not provide the correct resistance for the gauge to give you an accurate reading.     It’s possible that the steep incline could’ve had something to do with you stalling,  did you have a full tank of fuel? could be a weak fuel pump.  


if you get  an inferred heat gun you can take the actual temp reading from the rad and not be guessing if the gauge on the dash  is correct 


Wonderful and lucky  to have such a knowledgeable mechanic neighbor who has been so  willing to be helpful and with a lift 

Sure helps to get thru your restoration more gracefully 




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