Really in need of some "expert" advice here, thank you in advance! My truck has a 460 in it out of a 1971 Lincoln, with 429 ThunderJet Heads from a 1968 Lincoln. Engine is equipped with an electric fan, I've not even had the valve covers off yet, so I've got absolutely no idea what lurks inside (po claims 500+hp, but definitely is going to require a little tuning to get it there). No leaks, except exhaust (getting headers after Christmas), engine sounds & runs great. Cruising down the road temp always sits right at 190, so I assume that is the thermostat that it has, however, anytime I set at an idle in the truck for a drive-thru, traffic jam, etc. the temp starts climbing until I start moving again. Yesterday it was only about 35 degrees here and the truck never got over 210. At 55 degrees truck gets to about 230, I am scared of what's going to happen to it when summer rolls back around. The waterpump does not leak, thermostat seems to operate properly, only complaint I might come up with is the air from the heater could be warmer, but I don't know for sure because it does heat the cab properly after 15 or so minutes. I haven't checked anything with my radiator much, except to know that it is full and antifreeze is in good condition (don't know the size of it). Is it likely that my issue is with my radiator? Does this engine combo just run hot due to the high compression? Is my electric fan just not moving enough air to cool the engine? I believe the engine combo has been in the truck for about 10 years, but have no idea if this is a new problem or not. Help me please!! I love getting new parts for my truck, but trust me when I say that it needs enough of them, that I don't want to purchase any that are not necessary!

 

Do you know the CFM rating of the fan? It might not be pulling enough air as you suspect.

 

I don't know cfm of fan, I suspect it has not been installed very long just from the appearance of it. I noticed the heating issue shortly after I got the truck home, at which point I noticed the fan was incorrectly wired as a pusher, switched it around, but the problem didn't get any better. I guess I need to do a little closer inspection to see what I can figure out about my radiator size and the size of the fan.

 

Since the engine can maintain a reasonable tempurature while the vehicle is moving, then it is safe to say that the cooling system is capable of exchanging enough heat through the radiator. As you mentioned the only time this heat exchange is not sufficient is when the vehicle comes to a stop. This tells me that not enough air is bening passed through the radiator. Although in one sentance you did state that at 55 mph, the truck ran at 230 degrees. Is this typical? Slow cruise and the vehicle is fine, but if you generate additional speed, then the vehicle runs hot again? I'm confused now, which by the way is not all that difficult to do.

If this is the case, then you might be suffereing from an undersized or restricted radiator, but it should start to get hot during a normal cruise as well.
I suppose ignition timing should be looked at here, because it might suggest that the timing is off, or at least the curve is not right.
This does seem to be a simple matter of not having enough air that is being passed through the radiator to sufficiently exchange heat.
Either too small of a fan is being used, or the fan is installed improperly.

I see a fan clutch eliminator stuck on the fornt of the water pump pulley and no fan. This might indicate a problem that the OP was trying to hunt down, by throwing parts at, and ended up selling the vehicle and quickly threw an electric fan on to do so.

Electric fans are fine, as long as they can move enough air to efficiently exchange the heat generated by the engine when the vehicle is not moving.

I can be sure that your engine runs well, and the PO's 500 plus horsepower claim sounds great, although from what I can see there,,,,,,, the intake, and exhaust do not support such an optimistic claim. Compression is an unknown, and this is also dictated by the pistons, as well as a few other factors, but you did mention that the vehicle does run at temps in the 200 degree range, and there was not a mention of any "hot start" issues, which tells me that the compression may not be all that high. This too supports the theory that you may not quite be in the 500 plus horsepower category yet.
I am not trying to rain on any parades here, only trying to shed some light on optimistic claims VS realistic figures.

possibly an undersized radiator as well as a fan that does not move the volume of air required to exchange heat properly. This should be a simple fix.
Ive got 521's and a 557 that will run at operating temps for hours. Under load or at idle, they will maintian a proper temperature.
With a proper cooling ayatem, yours can too.

 

Electric fans are not exactly great for coooling hot engines. Good E-fans are expensinve and cheap E-fans are not usually good. I've been through this game with my '91 Sonoma I stuffed a stout small block into. There was no room for the engine, no good airflow and it took two expensive E-fans to keep it remotely cool, even with a high dollar three row aluminum radiator. A lot of the guys who do the V8 conversions on S10's have to run a manual fan w/shroud to keep things cool enough. I would suspect that a similar issue is at work here and that your E-fan is just not moving enough air to get the job done. If it were a radiator issue then it would overheat while moving, for it to do it stopped only then it is surely a lack of airflow from the fan.

George

 

Hmm, it seems we posted at the same time and with the same thougths, what was that saying about great minds?

George

 

[quote=75F350;8202395] Although in one sentance you did state that at 55 mph, the truck ran at 230 degrees. Is this typical? Slow cruise and the vehicle is fine, but if you generate additional speed, then the vehicle runs hot again? I'm confused now, which by the way is not all that difficult to do.quote]

Sorry for being confusing, but at a ambient temperature 55 degrees, engine will go to 230 while not moving.

I too was suspicious of the clutch fan eliminator, and I do know that the po installed the electric fan shortly before my purchase of the truck, and now think he was chasing a problem too. He was definitely no mechanic, luckily I bought the truck, because I thought it was a great solid starting point for me.

There is NO hot start issue, I've been driving the truck off and on almost a month now, and haven't checked the timing because I loaned my brother my timing light and can't get it back!!!

And lastly, I definitely think the po was more than a little optimistic with the HP rating, though I don't know what lies inside, externally it is equipped with a Edelbrock Performer Intake, and what I believe to be an Edelbrock 650cfm carb/Holley fuel pump (with shadetree mechanic routed lines).

I believe the truck was put together about 10 years ago, and have a difficult time believing that it would have just been used with the temperature issue that entire time, but I have been wrong before.

 

75F350, I wanted to personally thank you for the time you invest in this forum. In one of my previous threads about my front diff (HP D44) you mentioned that the chassis was a 78/9. What are the ways that I can identify what year the chassis is? It appears that the frame rail numbers were destroyed during the 460 conversion, unless I'm just looking in the wrong place. I know the truck is a patchwork, with the cab being titled as a 77 F150, but sitting on a F250 chassis.

 

I can't see in the picture what rad you have in there. Everyone I talked to before I put My b.b. in sayed the 400's rad would be fine, yea right ! well it wasn't. After trying everything, H.V. pump H.F. thermontat, Different fans,(clutch fan made it worse) shroud, etc. I bought a new 4 row Super Cooler rad. & never had a problem after that. 90* day in traffic or on the highway it never overheats now.

 

Thank you for the kind words.

The guys here seem to have the same idea, and it does seem to be a flow issue. This again could be air flow (which now after the clarification seems to point) but could be ater flow. Too small of a radiator and this problem will occur a low speeds, so this may not be the issue.
As clarified, the engine can maintain temp when the vehicle is moving, so it seems reasonable that you are not moving enough air through the radiator as George suggested in his reply.

A better quality fan, or a manual fan with a clutch is what I would be looking at, I m sure the others will agree after the clarification.

Good rule of thumb and a decent experiment is to place a plain sheet of paper on the front of the radiator when the fan is running. If the paper will stay on the radiator, and not just in one spot, the fan is pulling enough air.
If the paper is not sucked up againist the radiator for every finned section of the radiator, then the fan is not sufficient.
Failure to dray enough air can result in hot spots, or hot areas of the radiator, and the water itself will heat up again as it travels through the radiator.
This is a general type of experiement but seems to be a reasonable one, and should give you an idea of adequate volumes.

I will go out on a limb here and suggest that the paper will only stay on the radiator in one concentrated area, and will not stay on the radiator in others.
This dead area recieves no assistance, and is not drawing any air, and is more than likely your problem area.

 

You have confirmed my original suspicion. I can assure you the paper will only stay in one area, the fan only covers a little over 50% of the radiator, so I believe my riddle has been solved. Looks like I need to pick up a new fan/clutch and fab up a shroud. Since I've got a little time before it gets hot here again, I might try to see what kind of electric setup I can pick up from a salvage yard, in the past I have always had great luck finding odd sized shrouds and fans from the most unsuspecting of vehicle when trying to reduce expenses on my racecars.

 

Just a bit of info, even an e-fan will need a shroud for the purpose of making it draw from the entire radiator. They are shallow and can even be made from baking sheets if you so desire. I've seen where adding a simple baking sheet shroud will increase the efectiveness of an E-fan by about half or more.

George

 

Thank you very much George, guess I'll give that a try first, was going to do that, and was told e-fan would not benefit from a shroud. Thats what I get for listening to the 1st answer I get, rather than pushing a little farther. Should be pretty simple, I'll get a shroud put together, and see what happens from there.

 

Sounds as if you have narrowed down the problem.A quick and easy check for the water flow in the radiator core is to use an infared gun and measure the top and bottom tank temperatures at operating temperature.You should see the bottom tank running 10-13 degrees cooler than the top tank.This will show that there is flow and heat rejection.If the temps run close together,or a quite a ways apart,this indicates a probable restriction.Let us know what you find out.

 

Here is what a shroud looks like on an E-fan. You can see how easy it is to make one from a baking sheet, just get an aluminum baking sheet, cut your holes and viola! Cheap fan shroud. If you need help making one I'll be more than happy to write up a how to.

George