I am currently building a 31 Model A coupe and after 2 years of building, I finally heard it run last night. However, it got really hot - 260 degrees. With it idling in the driveway for about 5 minutes. I have since removed the thermostat and tried again. Still hot.-260. I am running a mild 350 chevy with a flex fan and brand new 64-66 mustang 3 core radiator. The fan did hold a rag against the grill so I am guessing that it is pulling enough. How do I check the radiator for flow rate? Please advise. Thanks
mine runs 180 all day long same set-up. except for the flex fan, those are junk get a regular fan, and make sure you have no trapped air in the system sounds like you may have an air lock.
Mine did the same but with a short Walker radiator and a chopped 32 shell. -I Ended up backing the timing off some and it's been fine since.
A Mustang radiator is considerably smaller ( and thinner ) than a after market Model A or Deuce radiator. Where you live can affect the temperature of the engine ( I live in the HOT, Humid South ... it was 98 degrees here today with 90 per cent humidity ) ... I always use a raised up water pump ... so I can run the largest mechanical fan I can. I use " Z " series Walker radiators ... and a Walker Shroud. Also ... a vacuum advance on the distributor helps. So does proper timing and jetting.
260 is VERY hot. Are you sure you've got the right water pump on the motor? It could be a reverse rotation pump for a serpentine belt application. Also be sure your tune up is correct, too lean or too much(or sometimes too little) timing can make a new motor run very hot. The aluminum flex fans aren't the best, I've been using the plastic ones from Flex-a-lite and they work very well. A shroud is also a very good thing to have.
If you pull the radiator cap (before it warms up), you can watch the swishy swishy gargle in the cap neck. If the water is stagnant, then the pump is not moving, the heads my be blocked with rust closing off the return holes from sitting 2 years. Was the engine gone thru before the install? Cause it sure sounds like, "transplant rejection" if you ask me.
I run a SBC 350, mild cam, 8 degree advance, 64-66 mustang 3-core, it runs 180 all the time. Hit 230 on the initial cam break but with retiming and burping the radiator it went down. Check engine timing, radiator cap and bubbles in system. Your cam gear may have been one of those with the advance retard features find out if so and go from there.
I would say you might have an air block in your system. I would pull a vacume on the radiator. I would also use a little higher pressure cap I would go with a stock style fan and forget the flex-a-lite fan I know some that have even used the mustang on a 396 chevy with good results.
Ive got 4 cores in my mustang radiator. The steel is canadian. when it comes to radiator cores, I think canadian steel is A LOT DIFFERENT than the taiwaneese steel most often used. sounds like a timing issue if its that hot anyway, or air pocket in system so do like above and check first just to let you know....I use a flex-a-lite plastic fan I bought cheep from summit years ago. It has 90 degree blades and my rod never goes over 180. they are light so they wont wear out your water pump fast either.... truthfully.....It has always bothered me to have that plastic fan on my trad hot rod, but after multiple attempts to fit a steel fan into the space allowed that'd cool, I settled for that fan.....because you cant compromise on cooling that expensive motor...period I think the most important things on any car are 1.)Radiator/Cooling, 2.) Brakes, and 3.) steering PLEASE DONT PUT A NEW ELECTRIC FAN ON YOUR RADIATOR! a bit ago there was a thread started with a guy that put an antique fan shell on his radiator (from an old 40's household fan) that was the hot set-up
yeah....check out : "electric fans are ugly" posted on 2-13-07.... I cant copy the link here for some reason, but type the above in your search, and the fan idea/tech will come up......still a great idea in my humble opinion! good luck!
Do what you have to do to get it cool!!Not like you'd be running the only electric fan on this board.!! JimV
first thing i would do is buy another gauge ,what 12-15 dollars. put a new desert cooler in my 59 same thing happened, dang talkin about pissed,pop in new gauge wa-la. they do go bad.
i had a little bit a of a time getting my 3 row right with my 350. IT never ran that hot though. After getting my timing perfect, making a new shroud and running a 30% mix of antifreeze and water weter it runs 180 all day, max of 190 after commign off the highway. 260 in the driveway is crazy! definitely make sure your water is flowing before doing any more troubleshooting. definitely try another gauge too!
I run a bored hemi with a cheap ass mustang 3 core. Electric fan that I only need when running stop light to stop light. Did 15 miles in town today and it was 96 degrees. You need to check timing and carb jetting. Check the thermostat to make sure it works and if the radiator is low compared to the thermostat housing then you need to burp your cooling system until the air is out of it. Get it up to temp, shut it off and let the air out of the system through the cap slowly. Keep doing it until you get water without air. Another trick is to drill a 1/8 dia. hole through the flat part of the themostat that air can pass through as the motor heats up. I have to do mine this way because like I said above, my water neck it approx. 6" above the top of the radiator.
Check your gauge, if you think it's accurate check it in a container of boiling water, even if it's a soup can and a torch. That way you can check it without taking a chance on burning up your engine. Definitely check for flow. The serpentine pumps (as mentioned earlier) look virtually identical and when you drive them backwards (with V belts) you get maybe 30% of the standard flow. If it got that hot you should check the torque on your head bolts (studs?). Even if it has Iron heads. And what Flat Ernie said.
runnong same radiator in a very built 283 bored to make a 302 with 10 1/2 : 1 compression with a 3 row mustang and an electric fan and she runs 160-180 all day long in south texas heat like everyone said check for air bubble and change out that crappy flex fan
They cooled SBCs fifty years ago with mechanical fans, you can do it now. 1 more vote for ditching the flex fan and building a nice sheetmetal shroud.
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