Here goes the goose egg..

[Fellro]

I'm going to make that zero go away... I currently have a 77 250 with a 400 that is waiting until I get around to messing with it again, but it overheats way easy when it runs, justs gets hotter and hotter I tried to check everything I could think of, but to no avail. I had heard thermostat, they can be wrong, so I will have to revisit that again sometime. It seems to be having carb issues now, won't stay running. Oh the joy...

 

[d-kuzmen]

Had a 400 with with 351C heads, was a decent motor. Came out of a 70's wagon.

 

[mtflat]

I have a 77 F150 with a tired 351M that I parked about 6 years ago when I really got hooked on flatheads. There's a decent 400 in the shop and I've got enough pieces gathered to make it a warmed up 400, but haven't taken time to get the block to the machine shop. One of these days........

 

[d-kuzmen]

I took my 400 apart and had the crankshaft modified to fit my 351w when I built my stroker motor.

 

[msb71]

I'm going to make that zero go away... I currently have a 77 250 with a 400 that is waiting until I get around to messing with it again, but it overheats way easy when it runs, justs gets hotter and hotter I tried to check everything I could think of, but to no avail. I had heard thermostat, they can be wrong, so I will have to revisit that again sometime. It seems to be having carb issues now, won't stay running. Oh the joy...

From what I heard Ford made the cylinder walls thin in the 400 and the 351M's , mostly the reason why they ran so hot. I have a 78 SC SB out back I am parting out soon , it has the 351M in it , it ran hot on a cold day, always worried me , that needle would just keep climbing when idling in traffic.

MIke

 

[flareside_thunder]

I've got an 80 150 with a swapped in Modified that's bored 60 over and it runs cooler than my 95 Flareside.......Since I'm on this subject...what do ya'll know about D20E Heads....perf and mod wise....I got a set that came with the truck and I don't have a use for them......

JR

 

[TheRoadVirus]

Google is your friend.
http://www.google.ca/search?sourceid=navclient&ie=UTF-8&rlz=1T4ADBF_enCA260CA260&q=d20e+heads

 

[rxlmod]

i had problems with a 400 doing that. ended up cracking the block. try getting an electric fan they're pretty cheap and moves as much air when it idling as when you are higher in the r's. and make sure the fins are straight on the radiator. if that doesn't work try running some of that 10 degree cooler stuff in there that stuff acually works for a while.

 

[lenny1carl]

always change the radiator cap with the stat

 

[mudslut79]

You could need a new waterpump and thermostat doesnt hurt to look into it. If you do end up changing the thermostat and water pump i would suggest flushing the system just to get any kind of build up in the water jackets and exetra out. Hope this helps.

 

[havi]

Cooling system seperate from the engine itself is likely the cause of overheating.

 

[Brian_B]

Cooling system seperate from the engine itself is likely the cause of overheating.

Hello Havi.

Good to see you around here.

 

[Fellro]

Could you expand on that a bit? I don't follow quite what you mean...

 

[havi]

radiator could have blockage, cap spring might be old, hoses might be old and cave in, water pump might be bad, thermostat could be bad, fan belt loose, heater core could be bad (Mine went bad from mouse nests trapping moisture around it causing it to rust), heater core hoses (though usually they never fail except maybe a pinhole), and coolant passages inside the block could be blocked. Also a fan shroud is pretty much needed. If all of the above check out ok, then the cooling system is good to go. Could be a head gasket, but looking at the oil would be an indication of that. Next bet would be the plug wires are not in the right order, causing 2 adjacent cylinders to fire creating excess heat in that location of the head, or the timing is off a bit....which might explain the carb popping. What I meant by engine itself is the casting wall's thickness. If they were too thin, every 351M/400 would overheat, and a recall would have been put into play. I've never had a 351M/400 overheat on me except in the dead of winter (-30F) when the antifreeze was frozen and no flow got through the block, lol. It's a start anyway, and good luck!

 

[Fellro]

Rad was fine, it never really boiled over, just watched the aftermarket guage climb, ran smooth, don't recall popping except when lean, since it didn't seems to want to pump fuel, not sure if why as the pump was new and the cam button was ok, may have been sucking some air. Don't recall the carb popping you mention. It has been a while since I messed with this truck, and someone stole my distributor, so I have to start over.

Not to seem ungrateful, but this ain't my first rodeo either... it didn't lose any coolant, just would get hot per the gauge. I can figure out head gasket failures, which don't always involve oil in the coolant. I can notice hose failures, many lower hoses had the wire in them to prevent collapse, none of wich were happening. Water pump was new as well.

 

[havi]

no problem, just covering all the bases. Is it possible the aftermarket temp gauge is getting the wrong ohm resistance?

 

[Fellro]

It is of the mechanical type, capillary tube. I wouldn't think it would be wrong, but it is always possible...