im at the end of my rope. I have a recent rebuilt 454, 34 degree of timing , 160 thermostat , new water pump high flow, 2500 Cfm puller fan, 3 core alum radiator and yet she continues to overheat. At idle she is fine but after about 10 miles climbs to 220 and pukes. I'm running water and water wetter. I do not know what else to do. Please help any ideas welcome
Your leaving out a lot of pertinent information,what kind of car and how about a photo showing the front of the engine. HRP
is it truly puking or just telling you how much your system likes,let it puke out and don't add more. a rebuild will run hot for a bit.
Remember the Cooling Rule Of Thumb. Runs hot at highway speed - not enough radiator. Runs hot a slow speed - not enough fan. I think the OP knows if its puking or not. Gary
I broke in a blown 350 on a trip to OKC in July. We ran into construction traffic on the interstate and the temp went to 255* with a 17 # cap, I don't recall it losing any coolant. I did drill a couple of 1/8" holes in the thermostat to burp out the air in the block. You might consider that there could be an air pocket in the engine.
That radiator does not look tall enough ... The upper hose looks level in the pics which may not be allowing all of the air to be burped out of the motor. Sent from my Moto G Play using The H.A.M.B. mobile app
That radiator looks pretty short to me. Usually most upper radiator hoses run uphill off the intake to the radiator. Yours is barely straight out. I doubt that radiator will cool a big block. Your already telling us it runs hot at highway speed. What are the dimensions of that radiator? I've been doing this stuff a long time and have never seen a pulley fix an overheating issue don't waste your time and money. I would never waste my money on Snake Oil like water wetter. A properly designed cooling system works just fine on a 50/50 water /anti-freeze mix. Gary
The radiator is lower than the neck but by less than 1/4 an inch and I used a radiator funnel when filling the radiator is 3 core and rated for 800hp
Who is the manufacturer of the radiator? Hope its not made in China. You don't even need a fan at highway speed. I suspect the radiators at fault. Remember the cooling system Rule Of Thumb. It never lies. Gary
what brand heads do you have, I had a very bad situation once with a bad casting which created a dry spot in the head and it did the same thing after 2 years we figured it out, it would be a million to one shot for you but the heads I had were world products.
Are you sure your cap is correct and closed properly? on mine it did exactly as you describe until I noticed there was one more click to fully closed.
If you ever look at some old Vettes and even some modern cars that the radiator sits lower than the rest of the system, they have an expansion tank (degass bottle these days) to allow the whole radiator and engine to fill with coolant and the cooling system as a whole was designed for it. Yours is not. You need a taller radiator. You are missing out on quite a bit of cooling area and probably not getting it totally full and when it does appear full, when it heats up a bit and spits some coolant out that aggravates the problem. If nothing else, try moving the radiator up just a bit to get the upper hose above the thermostat housing. Just watch the lower hose and make sure it doesn't move up too high.
Why aren't you using a 180 or a 195 thermostat ? Your coolant isn't staying in the radiator long enough to cool with a 160 .
Been building engines professionally since late sixties. And usually a BBC with a constant overheat is because the builder used the wrong head gaskets. BBC engines use three different cooling flows thru the engine. Depending the year of block and heads.. Each take a different gasket or a block modification. Fel Pro publishes the correct gasket numbers and mods in their install guide. That comes in their sets.
Is that fan mounted in a plastic shroud? If that's what I'm seeing, it's probably part of the problem. Looks like it blocks most of the radiator and air flow when the car is moving. Some have rubber flaps that blow open to help but I don't see any. Gary
Dan, lots of info but not all are relevant. The thermostat, fan, radiator hose and shroud have nothing to do with your overheating. At highway speed you don't even need a fan or shroud and the thermostat should be wide open regadless of its setting based on the info you've provided. The only function of a thermostat is faster warm ups on start up. I've built several cars with electric fans that I shut off at highway speed and only turned them on at low speed. I believe the key to your problem is the radiator as you say it runs OK at idle. We're trying to help you. Be careful about replacing parts that won't fix your problem. It also looks like the radiator is installed too low or the engine too high. Gary
make sure the water pump is going the right direction and could be air bound. also if not rebuilt check the freeze plugs cavity for casting sand left over. had that issue on 327 chevy years ago
This is not accurate, the 185 thermostat will not cause the water to stay in the radiator longer, and the water does not need to stay in the radiator longer anyways, it needs to cycle from engine to radiator and back as fast as possible.
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