I need some help on an overheating problem
#1
I need some help on an overheating problem
I have an 86 F250 4x4 with a 460. First off, this truck has a new radiator, new water pump, new hoses, new timing chain advanced 4 dergrees beyond TDC. Timing set at 10 degrees, vac adv works and is ported vac.
At first I thought I had a couple of bad thermostats. Well I'm beginning to think I have some other problem. It has never gone over 240 degrees and only for a few second before it would drop. I'm running a 180 degree thermostat. It wants to run 200-220 degrees @ 2400 RPM. In town it will drop to 190 degrees. I run a Stewart Warner mechanical gauge that is also new, and reads just as the old one did. Today I pulled the radiator cap to find alot of pure white foam. I bleed out some air and it seemed to help alittle. I might add I drilled an 1/8th inch hole in the thermo to help with any trapped air. The new radiator has a new rad cap. When I say new this was all replaced in April. Also, I notice that when I raise the RPMs the top & bottom radiator hoses collapes the top the most I can feel liquid traveling through the hoses.
Can someone give me some IDEAS. or THOUGHTS. I'm kind of stuck at this point. I plan in the morning on pulling the radiator cap start the truck and see if I can see anything. The only thought I had was a compression leak into the water curcuit. HEAD GASKET? But without a thermo I couldn't get water temp above 140-150 degrees. That's why I changed it in the first place I had a Fail-Safe Thermo and it was stuck open. Second if it was a COMPRESSION LEAK wouldn't it blow off the presure relief on the cap?
Anyway thanks in advance.
I know there are some real sharp people on this forum, Please give your input.
At first I thought I had a couple of bad thermostats. Well I'm beginning to think I have some other problem. It has never gone over 240 degrees and only for a few second before it would drop. I'm running a 180 degree thermostat. It wants to run 200-220 degrees @ 2400 RPM. In town it will drop to 190 degrees. I run a Stewart Warner mechanical gauge that is also new, and reads just as the old one did. Today I pulled the radiator cap to find alot of pure white foam. I bleed out some air and it seemed to help alittle. I might add I drilled an 1/8th inch hole in the thermo to help with any trapped air. The new radiator has a new rad cap. When I say new this was all replaced in April. Also, I notice that when I raise the RPMs the top & bottom radiator hoses collapes the top the most I can feel liquid traveling through the hoses.
Can someone give me some IDEAS. or THOUGHTS. I'm kind of stuck at this point. I plan in the morning on pulling the radiator cap start the truck and see if I can see anything. The only thought I had was a compression leak into the water curcuit. HEAD GASKET? But without a thermo I couldn't get water temp above 140-150 degrees. That's why I changed it in the first place I had a Fail-Safe Thermo and it was stuck open. Second if it was a COMPRESSION LEAK wouldn't it blow off the presure relief on the cap?
Anyway thanks in advance.
I know there are some real sharp people on this forum, Please give your input.
#2
it sounds like it should be fine, but if youre worried about it maybe you should have gotten a bigger radiator since it doesnt cool well under load, maybe you should have just put the cam straight up- that 4 degrees advance could be alot of your heating problem too... but at the same time it really isnt overheating... the cooling system on these trucks was designed to run with a 195 thermostat, and you said yourself that without a thermostat it wouldnt get over 150... so as i see it there is no problem
#3
Originally Posted by darrin1999
it sounds like it should be fine, but if youre worried about it maybe you should have gotten a bigger radiator since it doesnt cool well under load, maybe you should have just put the cam straight up- that 4 degrees advance could be alot of your heating problem too... but at the same time it really isnt overheating... the cooling system on these trucks was designed to run with a 195 thermostat, and you said yourself that without a thermostat it wouldnt get over 150... so as i see it there is no problem
#4
Does the new radiator have the same number of cores as the old one did? Most of the 460s came with a 4 core radiators and most replacments are a 3 core. Ford tried the 3 core thing in the '83 and '84 trucks but went back to the 4 core after that. I know a 3 core is on the minimum side for cooling with any kind of warm weather or heavy load.
#5
#6
Brad, Yes I postive about the thermo being in right. I have gone through a dozen different thermos in this deal.
Bear, I think this is a 3 core. It is the stock radiator replacement. Those plastic pieces of junk. I tried to find brackets to install a REAL radiator in it a couple of years ago without any luck. A friend of mine works the parts dept for a Ford Dealership, he researched and came up empty. The nearest wreaking yard is in Twin Falls and it is 160 miles from there. Reno is next and it's 300 miles away. So I was kind of stuck. Thinking back I have never had a heating problem or the temps running much over the thermo settings until I put in the Cloyes TRUE Street roller chain set and set it 4 degrees adv for pulling 10,000# trailer.
UPDATE: I put in a 160 degree thermo I knew worked right. What I have found is that it appears to want to run 20-25 degrees warmer than when it was stock. Also this truck has factory oil & trans coolers on it. I do have a new USA made fan clutch that does really pull the air. As for the hoses collaping that ended with the 160 thermo. Does running 20-25 degrees warmer with the cam advance sound right? Any suggestions on upgrading radiator? ALSO WHAT DO YOU DARRIN, BRAD, OR BEAR BELIEVE IS RUNNING HOT ON A 460? Over 240???
Thanks guys for your help & thoughts. It is really nice to beable to come on this forum and find people who have more knowledge than I. I spent years as a mechanic. If I didn't learn anything else in those years I learned I don't have all the answers and to ask others. THANKS ALL
Bear, I think this is a 3 core. It is the stock radiator replacement. Those plastic pieces of junk. I tried to find brackets to install a REAL radiator in it a couple of years ago without any luck. A friend of mine works the parts dept for a Ford Dealership, he researched and came up empty. The nearest wreaking yard is in Twin Falls and it is 160 miles from there. Reno is next and it's 300 miles away. So I was kind of stuck. Thinking back I have never had a heating problem or the temps running much over the thermo settings until I put in the Cloyes TRUE Street roller chain set and set it 4 degrees adv for pulling 10,000# trailer.
UPDATE: I put in a 160 degree thermo I knew worked right. What I have found is that it appears to want to run 20-25 degrees warmer than when it was stock. Also this truck has factory oil & trans coolers on it. I do have a new USA made fan clutch that does really pull the air. As for the hoses collaping that ended with the 160 thermo. Does running 20-25 degrees warmer with the cam advance sound right? Any suggestions on upgrading radiator? ALSO WHAT DO YOU DARRIN, BRAD, OR BEAR BELIEVE IS RUNNING HOT ON A 460? Over 240???
Thanks guys for your help & thoughts. It is really nice to beable to come on this forum and find people who have more knowledge than I. I spent years as a mechanic. If I didn't learn anything else in those years I learned I don't have all the answers and to ask others. THANKS ALL
#7
I missed the hose collapsing thing. Hose collapses=no water flow=overheat. Usually a collapsed hose is caused by the pump sucking them flat because the thermostat is n backwards or is bad. I run a 180° thermostat and the truck runs 180° empty about 197° when the camper is in the bed and towing the quad or boat trailer now. Before it would slowly creep up to the 230° range and that's where I chickened out and pulled over and run fast idle, 1500 to 1800 rpms, to cool the motor down with no load. I knew it was a radiator issue because turning the heater on high would slow the creep down. It took twice as long to reach 230° on the same road. Oh yeah, I am running a 7 blade non-flex, non-clutch fan (a Ford item) so it real moves air when you hast idle it.
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#8
#9
id say anything over about 230 is questionable, you should have tried to order a 4 core radiator, and that you should be ok for short bursts at 240 if you still have the original cast iron heads... if you had gone aluminum id say keep it below 220 because aluminum is way more temperature sensitive than cast iron, and will warp and crack
#10
Originally Posted by darrin1999
id say anything over about 230 is questionable, you should have tried to order a 4 core radiator, and that you should be ok for short bursts at 240 if you still have the original cast iron heads... if you had gone aluminum id say keep it below 220 because aluminum is way more temperature sensitive than cast iron, and will warp and crack
If you have any IDEAS PLEASE let me know.
With the 160 thermo the truck runs 180-190 most. I can live with that. I don't like running over 205 for extended times if I can help it. TOO MUCH HEAT KILLS ENGINES. Yes I have cast heads. The engine is stock except for the cam adv. and an Edelbrock Performer Manifold & a 4160 Holley.600 CFM.
Thanks Again for all the help & ideas. Craig
#11
The collapsing hoses will cause it to over heat at higher RPM. Think about it. When the hose is collapsed, a LOT less water will flow thru and so you overheat.
Most hoses have either a coil spring inside or have heavy rubber ridges to keep the hose stiff. If you can squeeze the hose by hand and it squishes easily, then it is too soft and has no reinforcement.
The hose should never collapse at RPM.
Whenever I had the problem, I just replaced the hose with a factory OEM hose or a GOOD name brand with reinforcment ribs. I do not know if you can buy coil springs separately, I never tried.
Are the hoses OEM or aftermarket? Some cheap aftermarkets don't have the stiffness to keep from collapsing. You are lucky you saw the hoses collapse. Most people don't notice this symtpom. This is the cause of many mysterious "oveheats at high RPM but cools down at idle" problems.
The foam may be a symptom of the collapsing hoses. When they collapse the pump will cavitate, create foam. It also might be a symptom of an air leak or oil leak but in your case the hose collapsing is where I would start.
Good Luck,
Jim Henderson
Most hoses have either a coil spring inside or have heavy rubber ridges to keep the hose stiff. If you can squeeze the hose by hand and it squishes easily, then it is too soft and has no reinforcement.
The hose should never collapse at RPM.
Whenever I had the problem, I just replaced the hose with a factory OEM hose or a GOOD name brand with reinforcment ribs. I do not know if you can buy coil springs separately, I never tried.
Are the hoses OEM or aftermarket? Some cheap aftermarkets don't have the stiffness to keep from collapsing. You are lucky you saw the hoses collapse. Most people don't notice this symtpom. This is the cause of many mysterious "oveheats at high RPM but cools down at idle" problems.
The foam may be a symptom of the collapsing hoses. When they collapse the pump will cavitate, create foam. It also might be a symptom of an air leak or oil leak but in your case the hose collapsing is where I would start.
Good Luck,
Jim Henderson
#12
#13
I'm pretty sure the brackets, shroud and fittings for any '80 through '86 F150-350 with a 351 or 460 and all brass/copper radiator will fit your truck, at least that's what the mechanic at the junkyard told me. I temporarily used one out junker with a 351 in my 460 and it fit perfectly (it was a 3 row core, mine was a 4-row). All dimensions were the same except the core thickness.
#14
yep it wasnt until 87 model year that anything radiatorwise changed, but if it comes down to it and you cant get one to fit- how hard is it to drill 4 holes in 2 pieces of 1/8" sheetmetal? thats all youd really need for upper supports- maybe some duct tape for vibration damping if you cant find a rubber grommet
#15
Yea, I thought of that. But never really did anything because even pulling this 460 would never get hot. Before advancing the cam with a 180 thermo it would run 190-195 pulling in 100 degree temps.
I drove to town yesterday and with a 160 in runs 178-180. So I would say I set for now.
Thanks for everybodys HELP. If I run into a further problem I'll buy a 4 core radiator and figure out a way to mount it. The holes are all pre drilled, but in 1986 they changed radiators and went to alum. & plastic. Only offered a 3 core. Mounts will not fit the metal radiators 1980-1985.
I drove to town yesterday and with a 160 in runs 178-180. So I would say I set for now.
Thanks for everybodys HELP. If I run into a further problem I'll buy a 4 core radiator and figure out a way to mount it. The holes are all pre drilled, but in 1986 they changed radiators and went to alum. & plastic. Only offered a 3 core. Mounts will not fit the metal radiators 1980-1985.