So I am looking for some advice here. I have a Oldsmobile 350 motor, with a new water pump on it. 66 Mustang radiator with a pusher fan mounted on the front side of the radiator. I have a 160 thermostat and I still am having problems with it getting hot. It ideas at about 185 then when i start going it gets like 205 then when I stop it climbs to 220. And goes down a little but not much. Any ideas on why I am still getting warm readings?
Is this a new build or was it previously running, but at lower temps? Posted using the Full Custom H.A.M.B. App!
It was a new build. i got the motor from my buddy who had it in his shop for like 20 years. Which makes me wonder. But it has good oil pressure.
I had a problem similar and it turned out being the trans cooler blocking the radiator. Dont know how yours is set up. Could be a head problem? Easy test ive used is to fill the radiator to the tippy top attach a pressure tester and crank motor over( make so it wont run) and see if it builds pressure. Good luck i know how annoying over heating problems can be! Posted using the Full Custom H.A.M.B. App!
Are you sure that your temperature gauge is accurate? A friend of mine spend many $s chasing an overheating problem that turned out to be an inaccurate gauge! KK
Radiator too small or blocked would be first thought. Mustang rads aren't huge. 3 row? Posted using the Full Custom H.A.M.B. App!
Yeah its a 3 row. I know alot of people run them with 350's and they work good. Not saying its not that though I will do a pressure test on it and see what I can come up with
In my shop the radiator would get an infra-red exhaust emissions check. Basically you're looking to see if exhaust emissions are in the coolant (not good). One summer I diagnosed 70+ blown headgakets this way. If your area does emissions checking on cars you might think about paying a smog shop to quickly check the vapors in the radiator. Some kind of filter must be used so that NO coolant enters the sniffer. We use 32oz styro soda cups stacked on each other with staggered holes on the bottom so a "gusher" rad cannot contaminate the infrared bench. The bottom of the soda cup is squashed down on top of the rad neck. And then leave the clear plastic lid on. just poke the sniffer in the clear plastic just enough to get a reading on the infrared. You have no idea how many needless radiator/waterpump/tstat jobs we've eliminated. Infrared machines are also used at the more modern repair shops for fuel mix diag. Customer is usually clueless to the amount of trouble we saved him.
Take the electric fan off and use a mechanical engine driven steel bladed fan,,that will cure your problem. HRP
Imo electric fans work fine as long as you move enough air. Had clearance problems with my combo and had to alter the way the radiator mounts. Before you go nuts chasing fan problems make sure everything else is good. Pullers work better than pushers but maybe you need a shroud? Posted using the Full Custom H.A.M.B. App!
And besides usually (at least what ive seen) fan problems are low speed not so much at highway speeds. Posted using the Full Custom H.A.M.B. App!
Pusher fans are just another obstruction blocking air to the radiator. Lose the small Mustang radiator for a larger capacity one and fix your clearance problem so you can use a real fan.
My experience is if you do not have a puller fan or mechanical fan right behind the radiator (<1inch) you will have problems without a shroud. I have not seen any luck with Pushers in front of the radiator as the only fan. My 2 cents, Dan
Pictures would help. Pusher fan will hurt med/high speed cooling. Not having a shroud is hurting your low speed cooling and shroud won't work in a pusher. 289 rad to cool a 350 not going to do it. I would get a crossflow and a puller fan and shroud.
yep, post some pics of radiator/ front of engine. yes, the radiator may be too small-especially with fan on front. try search for aluminum radiators , which if of good quality, can be found in many configurations at a reasonable price. also, for places like the Radiator Barn that sells replacements and lists most measurements of each. fan should be as large as possible. have closed system overflow tank? have a relay and preset sender for fan or manual on/off? where do you have the trans cooler mounted? of course, condition of engine is something that you need check out too.
On the U.S. radiator web site, they discuss Mustang radiators. The early ones, 64-66, always ran hot. It wasn't until '67 they got a handle on it. On my '52 Chevy with a sbc, I was planning on adding a/c so I bought the best radiator I could find. I got one their "Desert Coolers" which is a 4 row triple p*** radiator. They come in aluminum or copper/br***. With the a/c off, it runs at 160. With the a/c on, it runs at 180. I also run a mechanical fan with a shroud. Another thing to check is your vacuum advance if you have one. Mine was stuck so the engine was running retarded. I swapped distributors and the problem cleared up. I hate overheating engines. Each car I've bought had heating issues and I eventually fixed them.
If it's cool when sitting and hot when moving, it almost sounds like there could be something restrictive in the system. A few clogged radiator tubes. Water pump possibly. Maybe in the block some where. I'm just guessing and tossing things to check. But it's odd to heat while you're moving and not when you're sitting. I used to use electric, but I didn't like the look, noise and maybe I never got one that moved enough air. But when I did have one, I mounted it as a puller. They seemed to work a little better that way. If you have to run one, I'd go to a junk yard and get one from a mid 90's Ford Taurus. Those things will blow like a hurricane.
am going to contradict some The radiator is enough if it flows proper. The 160 thermostat is to cool. Reason being, its not stopping circulation long enough for the radiator to dissipate heat.... 180 is what you want. Your problem seems to be air flow, and electric fans are not the answer. Yea you can put a big one on it, and it will work. But a good fan (Not a flex type fan) is what you really want. an electric fan only cools the radiator section its mounted to..... Make sure you have a spring in the lower hose, so its not collapsing.... I have a 350 with A/C and I am runnin a 1957 chevy truck HD radiator. Its a 2 core. and since I changed the fan, got rid of the electric ones, and put on a shroud. It now wants to run under 180 with A/C on...... I did run a mustang stock 2 core radiator in a 351 with 15 to 1 compression. It kept the engine cool. 190ish.... but drag racing repeatidly would cause a heat build up issue.....
The facts are, your radiator is too small, and pusher fans are the least efficient method of cooling an already too small radiator. There MAY be other issues, but that does not change the first two problems. That said, there are exceptions to every rule, and guys are gonna come on a tell you how a radiator half that size worked for them with a model airplane propeller for a fan. It may be true...but that anecdote won't help you. A good guideline is to follow what OEMs did. And no successful OEM car came with an undersize radiator and a weak pusher fan. Again, pictures are helpful, but won't change the facts.
So today I dug into the problem a little more. I took off the exhaust. And knocked a freeze plug out. and It was solid. Not really sure with what. But solid sediment on the backside of it. So I ended up knocking them all out and flushing the block over and over. I got it the best I could. So then i ran it, burped it and went for a run. Stayed about 175 180. Which was good. But when I stopped at a stop light it stated to climb to 210. But then I started moving again and it went to like 190-195 and wouldnt come back down. Is there a reason for this? Should I still switch the thermostats out? 160 to a 180??
Most def go 180 RoberShaw if you can find it. Glad I read this - was considering a pusher for my COE. Might have to consider a shroud or a puller after I see how she does with a new aluminum radiator. Found a Summit Racing you-tube tech that confirms a pusher is 80% as efficient as a puller. Did you use the radiator flush chemicals they sell? I always get the type you leave in for several days. Even after plain water pre-flushing the 318 in the Dart until she ran clear using a Prestone T-kit, the black **** that came out after a few days of driving with the chemicals looked nasty. Also an engine that sat 20 years. Keep us posted.
if that crud is in the block then it's in your radiator. a flow test might be a good idea, still don't like the pusher fan as the other guys said, don't worry about the thermostat.
Very simple - If it only is getting hot now when you are stopped, you are not moving enough air, PERIOD. And that electric pusher fan is never going to do it. The thermostat doesn't have a DAMN thing to do with this. People keep spreading this myth. READ THIS: Thermostats - many folks first response to an engine running hot is "put in a lower thermostat". The thermostat's Primary function is to get the engine up to operating temperature quickly. Cold motors don't run as well and create more engine wear. The thermostat also has some effect on keeping the temperature regulated, but ONLY on the cold side. If the cooling system has a 180° Thermostat and is maintaining the temperature at say 190°, putting in a 160° thermostat will NOT make it run any cooler - It can't. Both thermostats are fully open at this point. There is also a lot of controversy, or differing opinions about running without a thermostat. The arguments for running without are that you remove the restriction and it is one less thing to fail. The arguments for Not running without are that the water will circulate too fast and not stay in the radiator long enough to cool. Naturally the truth lies somewhere in between. Running without the thermostat does not cause the temperature to rise because of flowing too fast through the radiator, the reason the temp can go up is the water will take the path of least resistance and therefore flow mainly around the cylinders in the front of the motor and not circulate well in the rear cylinders, this may or may not cause the temperature to go up on the gauge, depending on where the sender is, but there is little doubt that is causes much more heat in the rear cylinders. When the thermostat is in there, it creates some restriction which causes the coolant to flow more evenly between the cylinders throughout the block. The other reason Not to run without a thermostat is you will increase the speed of the coolant and this can cause friction wear in the radiator, especially in an old car with a lot of rusty contaminants in the coolant. It works like sanding the inside of the tubes and can cause a radiator failure.
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