help it runs hot. i have a 1978 ford f-100,lwb,302,2v,c-6,stock9 for rear, the 302 was rebuilt around 8 months ago by a local race shop here in savannah,ga. punched 60 over and everything else as stock as can be for longevity. bought a new rebuilt carb motorcraft 2150. new high flow hd waterpump, new 3 core welded all aluminum radiator from champion, 180 deg stat, new belts and hoses, plugs, i have tried motorcraft stock for truck then platnium, fomoco racing wires from summit, accel brass rotor and cap, timing set at factory settings for motor as per books, (fomoco 1978 truck shop manuals complete set). trans was rebuilt 2 weeks after motor, rear end rebuilt 1 week after trans, all new brakes (everything, all brakes new with fomoco), and nothing is binding it's been in the air and manually spun the wheels. ne wheel bearings. exhaust system that one i kind of question, its a 2 into1 into a giant toyota muffler done by a local shop here as well, have had it in a few times to check flow and even other shops say its not restricted and has more than enough flow but i still question it. drive shaft rebalanced w/new u joints. shocks, steering box, dash, guages, wiring, a/c all new and everything works as it should except it gets hot, w/o the a/c running. yes it has the shroud and the factory non clutched fan. i have even tried the clutched fan for a earlier year with the same motor set up and to no change went back to stock set up w/o clutch, i have even tried running the heat to help and nothing. i mean after shutting it off temp can climb to 220. never seen higher. during operation it can go from 180 for a while and looking good then up to 210 before i freak out and shut it down. it's like it continually builds heat while driving and then can no longer disapate it. it will maintain 180 for around 15 minutes then forget it, regardless if it stopped or moving, even at idle 15 minutes of 180 is all i get. any thoughts? this is my daily driver and i am about at my wits ends. help please.

 

With my new engine I installed a new faulty thermo s., replaced it and it worked fine. Now, something that alarmed me was that I was used to having the temp sender in the block. With my 180 thermo I could see on the gauge each time it opened. And it ran on the freeway at 180. Then I switched to the thermo housing for the sending unit. There I'm reading the hot water coming out of the engine, and with a 180 my gauge reads 200. When I shut it down on a hot day it'll jump to 220-230, but then my electric fan cools it in no time. My point is that even though my gauge says that, I know the coolant in the engine is about 20* cooler. Where is your sending unit?

I would ck your bottom hose and make sure it is not collasping when the thermo opens. A spring inside it is a good thing.

You might want to install an electric fan. They kick butt, and are cheap and easy to install. Mine will send the temp from 220 to 190 in about 2 minutes. It moves about 3400 cfm, flowing air like being on the freeway when sitting still. And it costs about $100. There are a lot of threads here about them, just run a search on the Taurus fan install, or Mark 8 fan install. Mine is a dual system, so if one burns out, I can still limp home. It is out of a late 1990's ford Contour or Merc Sable.

Good luck.

 

It's the Toyota Muffler. Dont take this the wrong way, but if all of the above statements are true, you would have no issues. By that I mean, someone may have made a mistake or something. I assume your fan and shroud assembly match. Your new radiator has never had coolant sealer in it (sealer plug's the aluminum cores fast!) Your cam timing gear is not retarded. Your ignition timing is not retarded. Your water pump actually pumps. (I bought two that had the impeller missing) Your Tstat is 195 degree's. Is the temp sending unit mounted in the head or block?

With all that, are you sure your temp guage is acurate? I've seen new sending unit's and guages be defective, Autometer, ect. While driving without a load, your truck should run it's coolest, not gain heat if everything is correct. Correct air flow, coolant flow, exhaust flow, timing is your friend. I'd buy a another mechanical temp guage with new sending unit and compare it to the "old" one. My 76 F250, 390, in last weeks 102 degree day with the AC running, did fine in traffic. If it was a 360 or 390 I'd say the head gasket's were reversed. I've seen that many times cause the exact same problem you describe on those engines, and even Volvo 4 cylinder engines. I'm not sure about the head gasket's on the 302's though. Mayby someone else here know's if that can be an issue. There are way's to test and isolate your problem. We are here to help. The electric fan option is fine, it helps with city driving and saves HP, but that should not help your overheating issue while driving if your fan shroud and fan are a match, for example. I Pulled a 24 ft fiberglass boat today, no overheating issues. After getting home, the truck idled for 1/2 hour on this 93 degree day while my neighbor bragged about the fish he caught, no overheating ssues.

 

It's going to heat up after you shut it off, that's called "heat soak"

And 210 running is not hot, 195-215 is considered ideal for engine wear and condensation. I wouldn't sweat it (pun intended) until the engine starts hitting 230+

In my opinion the factory fixed fan is complete garbage, but should maintain around 200 degrees with a 195 t-stat.

Josh

 

That's about what mine runs on the hot day's under load. The fan blades run about half in and about half out of the inner fan shroud edge with about a 1/2" gap from the outer fan blades to the shroud.

With that being said, what do you recommend? A flex fan offered no improvement for my application, although I've ran them on several cheb's with mixed result's. I have no issues with the fan clutch in most normal setups's, the electric fan save's HP, but has neglible effect for cooling while driving down the Hi way, but is awsome for 4 wheeling, rock crawling, city driving, etc. The stock set up is not the best for any situation, but serves well for the average ride. The electric fan has more failure issues than a mechanicle fan for the average driver. I'd bet very few people here have a electric fan installed in their truck. Then again, the average driver does not own a beast such as these. The original set up has lasted over 35 years with just an occasional belt replacement, not a motor, temp sensor, wiring, etc problem. If that sensor, motor goes bad in a normal city enviroment, these big engines overheat fast, not like an aluminum 4\6 cyl that's in the average car. I replace\repair them almost daily. The BEST setup is all subjective and based on your particular application, IMHO In running the quarter, I use no fan.

PS: A cool thing to do is splice into the wire going to your AC compressor, wire it to a relay that feed's a electic motor mounted in front of your condenser. This helps keep you cool in city driving on the hottest day's if you have the stock fan setup. Look at the head pressure with the electric fan operating and then shut off on a 90+ degree day. If the AC system is charged by weight, you will feel a differance on temp output on the hottest day's. JMHO

 

On a hot day my 390 will go from 205-215 normal temp up to about 230-235 when I shut it down and it heat soaks its not an issue to me and won't hurt anything.

 

IMO, that's not running hot - it's more normal than anything else. I share the opinions of Bullitt390 and Ford390gashog.

Remember that anti-freeze mixed with water raises its boiling point. Coupled with a 13 lb. cap, it is raised even more.

 

originally started with a 180 stat it never closed, book said 195 so i went with a 195, again same issue, now back to 180 after new rad, hi flow waterpump, and new coolant. bottom hose is not collapsing checked it many times for fear it was. i will go with the electric fan(s). the only thing that kills me is i can't tell any difference in the flow between the two waterpumps.

 

riderman, i hear ya of sitting in traffic all day and maintained temp, heck i had a 1970 429did the build myself and this was the best motor i ever had hands down. now with this 302 the motor is so common i am really thinking it's me cause there are to many of these out there for problems like this. i am thinking of going back to dual exhaust,really starting to agree on this one. the fan and shroud are a match and properly set. radiator is brand new champion 3 row. should i go 4 row? timing is 8deg btdc. as per book. water pump is a good one, i can see a flow but not the volume increase i expected to see from the hi flow compared to the standard one. stat was 180. then went to book specs and went to 195 then with new radiator pump and stat it was recommended to go back to the 180. and thats where i'm at now. as for the temps i think i will try some digital sensors aroung the motor. thanks.

 

bullitt390, that helps my concerns a little with the heat soak. and i agree about the fan thats why i went with the clutched style and then back because you still see these trucks on the road and a very high percent still have the origianl fan. so that tells me ford knows more than me so i went back to the origianl design.

 

riderman, mine is runnning these temps and not under a load, yes the fan is right with half in and half out with 1/2 inch clearance, and i have treid the clutch with no difference. i'm just to the point where i will really ahve to use this truck for a long time to get a romi (return on my investment) i'm here cause i'm almost at the point of cutting my losses, i loved the first ford i had it was a 1970 429 built myself and would have driven it anywhere at anytime. it was right in all respects and this little 302 is kicking my but. everyone keeps taling electric fan i will go that route as well and hope to come back with good news soon. thanks.

 

ford390gashog, thanks for the heat soak statement it makes a lot of sense and 205-215 is a normal operating temp for a 390 but what about a little 302? got a lot of money and time in this thing and hate to lose it all to a minor issue i have overlooked.

 

hio silver, thats true i did know that about raising the boiling temp but my greatest concern is how much does it raise it? to what temp? and what are the acceptable temp ranges for this year and size motor? i am fearful of losing all this to something i overlooked and i agree strongly with kiss (keep it simple stupid) not referring to you, i am referring to me. and making sure i am taking a step back and keeping it as simple as the ones who designed this machine. heck it kills me bacuse there are so many 302's out there and have been used for so many years that i know this is something i am overlooing because by now the junk yards would be full of 302's and the word would be out by now, so i know its something i'm missing. i have even debated on tearing down the motor again just to be absolutely sure. know what i mean? i wil try a few more things before i go that route.

 

As long as you are not boiling, your good.
What you describe is not over heating and a 180 degree thermostat is too cold. Should use 195 degree.
It can go very high when cut off the engine with no problem as long it does not boil over. (violent steaming Hot)

 

50/50 coolant has a boiling point of 265 degrees with a 15 pound cap.

Josh