I'm new to the forum and new to "street rods". I ran a search for over heating problems and didn't find any topics. I just got a 55 Ford F 100. It's not the conventional ride. It has a 68 Camero front clip with a Chevy 327, duel quads, aluminum heads. Don't have all the specs on the engine.The problem is it's over heating. Has a big aluminum radiator with electric fan and has air conditioning radiator in front of the radiator. Hooked the electric fan direct so it stays on all the time. That didn't solve the problem. Changed the thermostat out to make sure it wasn't sticking with a 180. That didn't work. Added "Wetter water?" that didn't work. Took the thermostat out completely and it's running cooler longer but it's still over heating. If I punch it, the temp goes nuts. I have a 160 thermo but haven't tried it yet. Haven't run a radiator combustion test yet to see if I'm getting gas in the water but I don't see any signs of needing a head gasket or cracked head but I might be wrong.Does anyone have a list of simple fixes I should check before I pull the heads? Bigger fan, electric water pump, etc? Thanks in advance for your suggestions.
first... when it overheats what exactly does it do.. does it blow the coolant out???does it get hot and stall.. like coming to a corner and idling for a few minutes.. or get really hard to start when hot.. i have some quick tests for you .. cheep too... find some sandwich wrap. and a rubber band.. cold engine.. remove radiator cap.. lay sandwich wrap across radiator neck.. push a depression into the sandwich wrap.. use the rubber band to seal it to the neck.. be sure to block off the overflow tube.. start the cold engine for 15 seconds or so.. shut it off.. does the depression still exist in the sandwich wrap???? give a hose a squeeze make sure the sandwich wrap responds..if you find that you have puffed up sandwich wrap. its time for additional tests.. if you have access to shop air.. you can perform a cylinder leak down test.. hint.. i usually use my compression tester hose with the valve core removed.. so there is no restriction. a remote starter button really helps move the crank around in tiny increments.. if you get bubbles out of the radiator.. you have found the leaking cylinder...this cylinder leak down test is probably the best idea for you if you can get direct access to the spark plugs past the probable header tubes.. please do the small investment of a infrared temp gun.. on a cold start.. you can monitor the circulation and the increase in heat..
a few questions from wayne...when you punch it and the temp goes crazy.. i am taking that this is not an instant temp gauge movement.. overheating takes several minutes... if its an instantly overheat.. i would perform a voltage drop test as you are probably running an electric temp sending unit that only has ONE wire to the gauge.. the ground side is is the other half of the circuit..this is printable.. or copy the image to your computer.~~~~~~~~~~~~~~~~~~~~~~~next.. well actually this should be done first.. pull the radiator cap off. shake it. look at the dime sized disc in the middle of the rubber seal.. does it dangle loose. or is it spring loaded against the rubber seal.. if it dangles.. replace the cap with one that does not have a dangle. i have had to do so many head gaskets because of these weird caps that don't hold pressure unless the coolant is pushing the disk against the rubber seal..
how is the fan hooked up??? running a fan constantly will usually overheat the armature.. wear out the brushes if its a brush type.. it can also melt the middle of the fan blade out as the shaft can get that hot .. usually radiator cooling fans are hooked to relays.. so the control device is only controlling and switching an amp or two of power.. the relays can be wired much closer to the battery with larger wires to keep the fan spinning at max speed.. with electric cooling fans.. or even conventional fans and belt driven water pumps. there is almost always some kind of bypass circuit.. that allows the water pumped into the block around the cylinders. up the back to the heads.. forward thru the heads and into the intake manifold crossover where it is stopped from going thru the radiator by the closed thermostat.. the bypass allows coolant circulation. as it allows the coolant flow thru the block and head.. past the closed thermostat and into the water pump where it goes around again and again until it picks up enough heat to open the thermostat.. then the hot coolant moves into the radiator and the cool coolant moves into the engine.. when the cooler coolant contacts the thermostat.. it closes it.. this allows the coolant trapped in the engine to circulate around many times and thru the bypass circuit.. but the hot coolant in the radiator is stopped so the ram air and the fan moved air can take the heat out of the coolant.. without a thermostat. the coolant moves so fast thru the engine and radiator that it does not slow down. causing it to get hotter and hotter and hotter. or worse..changes in engine speed can shock cool the engine.. so its heating up under acceleration.. and super cooling when you are slowing down.. this is very hard on the head gaskets and cylinder heads.. as they have to live thru many additional heating and cooling cycles than they were designed to survive thru. i can go on explaining cooling system thermodynamics. if you like..
Thanks for the tips. What would be the highest temp the engine can safely run?
aluminum headed corvettes in the 80s and 90s ran at 228F to 238F.. without damage that's when the fans turned on.. most cars with 13 to 16 psi cooling systems and 50/50 to 70/30 coolant to water can run easily at 245 without a lot of issues for short times. long uphill grades.. one thing. with really high engine coolant temps.. you want to make sure that the transmission oil temps do go crazy also.. if you could keep your transmission fluid to 165 to 170F the transmission will last for many years.. if the transmission temps creep up over 220.. transmission life will be shorter. only way to prevent this is with additional transmission services.. so 20K instead of 25 to 30K miles.. i have a friend with an E250 ford van. who listened to me about transmission services ever 25 to 30K.. his lasted to 475K. and if the shop who did the last change.. had not used type F which was too thick . he would still be going.. dacron filters don't like more than 2 quarts out of 12 of type *** brass screen transmission filters don't care.. nylon screens blow big time. but thats off thread.. HF has two versions of this type of infrared temp gun.. hint.. its good for back yard cooking.. and many other things around the house and shop.. http://www.harborfreight.com/non-contact-infrared-thermometer-with-laser-targeting-60725.htmljust having it around to check the warm up cooling system by aiming at different areas of the engine as i described above can really solve issues. sorry.. i am a mechanic.. i have tons of tools.. i have like 6 scan tools.. probably 5 or 6 digital volt meters.. a flexible scope camera.. a flex wand type infrared thermometer.. a digital hand held scope.. DC amp clamps.. almost as many sockets as a snap on truck.. i would have more but i never replaced all my snap on and mac stuff when it got snatched back in the mid 80s.. i don't even know how many boxes of manuals i have..
Wayne, thanks for all the input. Like I said, I'm a neophyte. I haven't tried the sandwich wrap yet to see if exhaust gas is leaking into the water system yet.So based on your last reports, maybe my engine isn't really getting to hot at 230 or did I miss read that.
if the system holds pressure.. 3 degrees increase in boiling point per pound of pressure.. 13 pounds add 39 degrees.. 212F to 251F..mechanical pressure at speed stuck behind the thermostat adds even additional increases in the boiling point inside the engine at high speeds.. so the exhaust ports and exhaust seat areas are not causing boiling.. and you have 50% to 70% coolant to water percentage.. can take the 13 pounds to about 265 F boiling point.. and it won't be exhaust gasses that you find with the shrink wrap and cranking. it will be compression from head gasket leaks and combustion chamber crackshere is a cylinder leak down test described..http://www.carcraft.com/techarticles/116_0406_cylinder_leakdown_tester/viewall.htmlneed more info.. i drop thru daily..
warning.. having an infrared temp gun to verify that your gauge does not just stop at 230.. i would prefer a cooler motor.. got pictures of your set up..photobucket is free and easy.. you can even do videos to youtube .. they are free also..
Wow, Wayne, way to much overload for me. I really don't know where to start. The most I know about the motor is it's a 327 with duel quads and a 3/4 cam and aluminum heads, electric fan aluminum radiator. It has air conditioning radiator and fan in front of the radiator. It has 19000 miles on the motor, I assume from last rebuild. I'll take some better photos of the motor and post on photo bucket.But, I thought if I have a 180 thermostat, the motor should run about 190 and it's getting up to 230. I haven't run it that long, I've shut it down.Looks like to me, worst case I need a new head or new head gasket. Or I might get lucky and just need a bigger fan. I haven't taken it into a shop yet. Approximately, what does a new aluminum head cost?
pictures will be great..and... THERMODYNAMICS is a mystery to almost everybody.. you are dealing with that term... and trying to create a heating and cooling system that works.. i just worry that your temp gauge might be off.. and before spending money on a new radiator... switch up to a 192F thermostat..what happens in some systems is the engine can build heat faster than the radiator can loose it to the airflow .. so after a few cycles of thermostat opening and closing. the cooler coolant coming out of the radiator is hotter than the closing temp of the thermostat.. this causes a runaway cooling system... as the coolant gets hotter and hotter and the thermostat opens more and more flowing coolant faster and faster thru the radiator where its going TOO FAST thru the tubes to loose enough heat.. so you have a runaway cooling system.. change the thermostat to a 192F .. make sure that you have the 50% to 70% coolant. 100% works.. but coolant straight does not absorb heat from the block and heads as well as the 50 to 70% blend.. water wetter helps this.. but it does not effect the too low a temp thermostat for the system.. increasing the fan size or blade pitch/ count. length..some flex fans have 5 blades.. some have 6 or 7... some have narrow blades.. some have medium wide blades.. some have really wide blades. it all depends on how much air you need to move thru the radiator.. verses how much power you will give up to spin the fan.. i should not even mention loosing power to spin the fan.. but you pay to have a properly operating system.. there is no free lunch.. think of a top fuel drag race motor.. they are making like 8,000 horsepower out of 500 cubic inches.. the super charger at full speed i seem to recall requires something like 3,000 horse power to spin.. but without that loss.. they could not make 8,000 horsepower at the back of the crank.. its a good thing they can rebuild those motors in 45 minutes.. and they only have to run for a about 2 minutes if you include warm up.. 5 seconds of tire burn out and 5 seconds of full throttle acceleration.. i wonder how deep the oil is on the back of the crankcase during the run.. look at the new corvette LT1 motor on a tilting bed dyno to duplicate acceleration.. braking and cornering forces on the liquids in the engine.. tilting dyno LT1 corvette engine run 43 seconds videoi will love to see pictures.. just paste the links.. i can get them up for you..
So I should be going up on the thermostat instead of going down. Changing out the gauge sounds like an easy check. Wayne, you should be able to click on this link and then click on the video for info and pics of the truck. streetsideclassics.com/showcar.php/dfw/558/1955-Ford-F-100
thanks.. change your heater control valve to a 4 port version that will bypass coolant back to the water pump when the heat is not called for.. or do a test drive with the heater control valve open at least part way open so you get some bypass circuit going around. ... this allows the coolant in the block and heads to circulate thru the block and heads until it reaches opening temp.. then it starts cycling block heads , block heads, block heads... radiator, block heads, block heads, block heads, radiator.. this gives the electric fans a chance to cool it with it stopped in the radiator. the increase of thermostat temp also increases the difference between outside air temp and the coolant. instead of throwing a new temp gauge at it.. invest in the temp gun. http://www.harborfreight.com/non-contact-infrared-thermometer-with-laser-targeting-60725.htmlverify.. or stop by a radiator shop or most mechanics shops.. ask them to aim their temp gun at the coolant passage on at the front of the intake to see if the temp gauge is reading properly.. and a heads up.. i am trying to help you .. not pay the rent on my shop.. so when you get advice.. if it starts getting expensive.. you understand whats going on.. sorry everybody some but not all shops are like that. i hsve been yelled at for 20 minutes because a nut flew out of my socket rolled across the floor and went down the floor drain.. that my asking for a 10 cent nut as cutting into his profit margin.. i ask him how a 1 buck modulator hose was billed out as a 736 buck transmission rebuild the week before.. only have the cars that come into that transmission shop actually need a rebuilt transmission.. what was not said.. is that every car that comes in.. gets a transmission.. if it needs it or not.. another transmission shop that i actually liked.. had a range rover model collecting dust in its parking lot.. i ask.. it won't go over 25 miles an hour.. change the engine coolant temp sensor and pigtail.. that's what's wrong. it was... wow.. were they happy to get that out of the parking lot.vacuum operated..1985 CHRYSLER NEW YORKER 2.2L 135cid L4 Turbocharged : Heat & Air Heater Valve EVERCO Part # H6325Vacuum Heater Valve AIR CONDITIONED,w/TURBOFOUR SEASONS Part # 74776 or a cable operated version.. that is easy to get out and push open or use a push pull cable that are easily available.. Everco/Heater Control ValveChrysler Newport 1972 1973 Part Number: 74643Alternate Part Number: 74643you can also just fit either this H pipe..with your existing heater control valve between this H pipe and the heater core. so closing off the valve does not block the flow...pick up two of these .. put on in each hose.. again with your existing heater control valve between this and the heater core.. and a short section of hose between the side outlets on the TEEs.. this gives you bypass for way CHEEP.. might cure your issue..