Hot Rods another cooling problem

heres the story:

303 olds
mustang rad
mechanical fan

ive tried everything, flush the system, flush the radiator itself for about 30 minutes, tried no thermostat after a friends car runs cool that way, tried thermo stat... tried all water, tried 50/50 mix, tried 30/70 mix, etc...

some days, it will run 175-185 all day, some days like today, it gets up to 210...

i CANT fucking figure this out...

some days it pukes a lil, some days it doesnt... only pukes when stopping..

any ideas???

 

ps 95% city driving, but once its heated up highway wont cool it off..

 

what mustang radiator do you have? 2 rows suck, & i even had a hard time keeping my mild 289 ford cool with a 3 row. you sure its enough radiator for the car? if so then tune the bitch. make sure its not running lean, also make sure you have enough advance in the distributor. also make sure nothings jacked in the distributor, broken springs, weights, etc.

 

yeah i gotta look into the distributor too...

also, the fan is about 2 3/8" from the radiator, less than ideal but spacers are ugly (may need to go that route though) 3 row radiatoor

the issue in my mind is that it isnt a constant, thats why i cant figure it out

 

1. check engine timing.
2. be sure all incoming air is going through radiator core. If there are any air spaces around the core/radiator shell opening air will always take the path of least resistance, block them to force air through core.
3. make sure your mechanical fan is within 1 to 1.5" of core. That 3-3.5" gap you've got means you just don't even have a fan functionally unless you build a shroud.
4. fabricate shroud if all else fails.
5. use thermostat.
6. 50/50 is best mix for antifreeze/water.
7. check your radiator cap pressure rating, buy a new one.
8. if you don't have a puke can, don't fill radiator to top. every radiator which is used with low(no or 3-5 lbs) pressure caps has a level at which it will not puke water when you stop. Mine are generally about 1 inch below the bottom top of the tank.

 

ps - open hood 31 coupe... seen below..

i will not run a shroud, i would rather stop every 5 miles and cool it off haha

plus, its not an every day issue

 

if your fan is 3 inches away its not doing shit!!!! also, might run cooler if you polished those americans

 

hahahaha, if i could afford it i would polish the lips!

and they are ET's on back, Superiors on front! but thanks!

 

Are you sure your temp gauge is acurate? Weve ran into this issue on some boats at work. Banged or heads against the wall only to find out it was a bad gauge.

 

I'm not a big believe in mustang radiators. Tried one in a Chevy Luv with a mild sbc I built for my Dad. Didn't work and it was brand new. I had a radiator shop custom build one. The custom one worked so good I put a thermostat in it.

 

I think it's the grill insert.... there's not enough air getting through it to cool the water down.

 

johnny, you may be right, but i dont wanna give up on that yet hahhaa... it seems to be ok 70% of the time which is why this is so wierd

 

making a spacer? tell me you have a lathe. i wouldnt make one unless you have all the right tools to do so. could get real ugly! i didnt realize your radiator was blocked off by plexiglass. you do know thats 99% of your problem!!!

 

Lots of cars have a decent looking old timey fan spacer. The above is a Ford one but it is 2 inches ( about perfect for you car ) ...

Buick

Cadillac

53 Oldsmobiles came with a spacer, so they are Traditional
... go here to see one

http://cgi.ebay.com/ebaymotors/1953...yZ140681QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

Check your timing first... Don't believe the no thermostat bull... They make them for a reason. I know it's gay but you may have to go with an electric fan with a temp switch. But Jonny is right that insert is blocking a shit load of fresh air. Good Luck

 

I've got one of those caddy fan spacers if you want it, todd.

 

i do fear the plexi is the issue.. but doesnt solve why it runs cool most days..

either way, i need that spacer johnny!

id like to make it to the cheaters show after work next saturday

 

Is yor timing, vac advance etc staying the same? Bad dizzy???

 

vac advance not hooked up

gonna check over timing as well

 

i'm running a 400SBC which is known for running hot with a 2 core mustang & it works fine, it also runs about 185 (thats the thermo) & gets up to 210 sometimes, no biggie.
Put a piece of paper over your radiator with the car running, if the paper sticks the fan is close enough.you can stick a elec.fan behind the grill, paint it flat black.the thing that gets me is that you said if it gets hot running down the hiway doesn't cool it!1 that usually means the rad is clogged.Even most flushes won't get out the real calcium build up in a rad.You might have to have it rodded.
You can also try a little muriac acid delluted alot!!Maybe 2 cups per 5 gals, get one of those small drill driven pumps, make adapters to fit washing machine hoses to it & go from a 5 gal pail thru the rad & dump it back into the bucket, flush it for about 5 mins. also do it the opposite of the normal flow. The flush will turn a green color at first the clear a little, you'll be amazed at how go it works.just do it outside wear goggles & rubber gloves, not too strong of a solution & run baking soda thru it when you finish. Check out all the shit in the bottom of the pail when your done!! if it doesn't do it add another cup of acid
jimV

 

well the radiator isnt even a year old really, so i dont think its fucked up, but may be

just so people know if they cant see there are holes in teh plexiglass, about a dozen, and not tiny ones either..

the paper trick is what i did earlier just to make sure it was going the right way. i had to have it reved some to even hold a newspaper add, so i know the fan isnt close enough

 

just so people know if they cant see there are holes in teh plexiglass, about a dozen, and not tiny ones either..

i didn't realize you had plexi over the rad,try it without it, its amazing how much it could be blocking the flow.If it doesn't make a differance try the spacer.
JimV

 

im gonna try a spacer first, then go from there..

i just wanna find an old one or a decent looking one... i dont want it to look to gay with the fan that far out from the pulleys

 

I've had a similar problem. Tried the same stuff. I finally found out that my fan (mechanical) doesn't pull enough air through the radiator. When I stop alot or drive close behind a big box truck it begins to heat up. If I can drive for a distance without stopping it stays cool. I have added a small shroud and am going to add an extension to move the fan closer to the radiator.

 

FIRST THINGS FIRST!!! The radiator is the HEART of the cooling system. First thing to do is pull it, go have one tank REMOVED at a radiator shop, and look for plugged tubes. If plugged with scale, flushing won't fix it. Also, make sure it has ample rows of tubes. Mustang radiators are pretty small to begin with. A 2-row's WORTHLESS

 

My money is on the plexiglass insert. Why it doesn't do it everyday is another issue. Outside air temperature, humidity, driving patterns, etc all play into it.
Remove the plexiglass, install a fan spacer and recheck your timing and I think your problem will go away

 

Groucho and MercDeuceMan nailed it, start by fucking off the plexi glass. Yeah looks great, works on a drag car but for something that gets driven further than 1/4 mile its about the dumbest thing you could put in front of a radiator!

Was the radiator brand new? Or was it a second hand re-manufactured one? It could be full of shit from the shop.
Was the motor fresh when you put it all together? I mean hot tanked block? If it wasn't you could have flushed all sorts of crud into the core even from a re-built motor if it wasn't cleaned real well.
So, lets cap this off.....
1, piss of plexi glass.
2, fan spacer.
3, pull radiator out and have it cleaned, not just flushed, while your there have the shop power flush the motor as well.
4, re-check timing.
5, drive happily thinking 'damn the HAMB is the shit for tech!'

And, last, I find I have to say something about thermostats. The fucking things are only there for ONE reason. That is to speed up the heating process on a cold start, at cold they are closed to stop flow, once the motor is up to the thermostat temp it opens its job now done until next time you start it cold. Now you dont have any problems there the fucker heats up fine!, take the fucking thing out and throw it at the next person that tells you that you shouldn't take them out.
Now if this same person, or another person tells you its essential in cooling, bend him over and insert the thermostat that you threw at the other clue less dick head to show him the meaning of 'Impaired flow'..
All it is doing for you is just that, impeding flow, if its cold let it idle a little longer before you drive it. Simple.

I learned this stuff from my father, he owns three radiator shops and specialises in custom cooling systems (And repairing those poxy Desert Cooler radiators). Someone with 50 years experience and 30 employees that uses him as the font of knowledge is someone to listen to.
Rant over, its not black magic.
Doc.

 

I whipped up a little fan spacer... we're gonna see if it makes a differance.

 

Todd, even though that radiator was new, how clean was the engine inside? Might have wash a shitpot of crap into the new core. Only part of your issue, try that spacer as well. I would also rethink the shroud issue, Bet you could make one that matches the theme outta orange plexi.

 

I agree, and I LOVE this guy!!! Too many people think there's some "magic" in how a thermostat helps cool the motor better....BULLSHIT! It's only there, as Doc said, to speed the warmup, and ABSOLUTELY NOTHING MORE.