I ran "Bite By Bruce" recaps with a soft compound no tread back in the late 60's early 70's. I used to slowly rotate the tires in a home made trays filled with lacquer thinner. Damn tire growth alone would eat tires from the wheel wells if not clearanced properly, don't ask. Yes many dumb things done as kids when we had just enough money for parts and gas.

 

Alright. Thought I'd let you guys know about my slow but surely bit of progress against this problem I've been having. I removed my shroud, fan, and clutch and ran the motor indoors in my shop which was at 72 degrees and about 50% humidity. I ran my laser thermometer across and up and down the radiator before, during and after the thermostat opened to find that all is well with the flow of my radiator. The temp was spread all across the core and became cooler the lower you measured. So that rules out the liquid flow of the radiator so I've come to the final conclusion that I need a small small pulley in order that I may turn the fan faster and pump the coolant quicker. Anyways, we'll letcha know after I get to the yard or ebay first and get that pulley turnin.

 

I have a 351 W that had the same problem with heat after a rebuild years ago when it was rebuilt the block wasn't dipped it was it beautiful condition after it was back together, ran hot. 2 years we tried to figure it went through the cooling system no answers finally we tore it back down and had it dipped and .10 honed off never got hot again my machine shop told me for some reason Fords get a build up in the cooling system of the block and it restricts the coolant just enough to cause it to run a bit hotter than it should. just my penny's worth of thought.

 

Can you splain dipped??

John

 

Hot tanked John.
This must of been done with the freeze plugs removed one would hope. Did you also rod the coolant passages, you will be surprised how many pounds of rust and scale comes out doing this?
You have the head gaskets installed correctly, there is a front and back?
While you have the stat off and checking it in a pot of water this would be a good time to poke a length or tie wire into the stat hole left and right until
you hit the blocked off passages by the head gaskets. You will know real quick if the head gaskets were installed correctly at only the cost of a stat gasket, coolant loss and a little time. If you have a flex fan they flatten out at higher rpm's becoming restrictive in air flow vs the old factory fixed pitch steel fan.
Your temp check with the radiator isn't solid proof the radiators good. They plug up with mileage and age. With both hoses off did you fill it from the bottom then let it drain on its own, water should flow out the same diameter as the lower radiator neck and empty within app 5 seconds. If not your tubes are plugged or restricted.
Another question, how many row radiator do you have?
Two row was on your basic truck no AC manual trans, 3 row with AC and auto trans. If it's radiator replacement time I would go to a 4 row or better yet a 5 row staggered tube.
On the 67 410 and I believe passenger cars in general the crank pulley was slightly larger than the pump pulley. On the trucks the opposite.
Going off memory of 20 years ago it was something like 3/8" difference between the two allowing for the pump and accessories to be overdriven.
Any two combinations work including small / small but no big / big for crank and pump as they will not clear.
Don't leave out the thermostat not fully opening or taking a dump, even new ones fail. Did you place the stat in a pot and heat it up watching the opening action plus check the water temperature during this test?

 

I have just been watching this post and wonder when the water pump was replaced last ? You could check waterpump pulley rpms with a proper timing light and compare ,,,,,, one more thing radiators can be flow tested to see if its becoming blocked or is blocked .

 

Hey What is the FORD part number on the larger 410 crank pulley ?????? Thanks

 

Block came out beautifully and freeze plugs were out. My machinist is amazing and we have built over 12 engines using him. Does he make mistakes? I'm sure he does just like me but he is def reputable so I trust him. Head gaskets are good. Standard Ford 7 blade stiff fan with mild pitch. The rad only has 22,000 on it and 6 years. I flow checked it last time it was empty and it flowed out in a real hurry. I know it was quicker than 5 sec's. It is a 4 row copper/brass modine. Biggest most expensive I could buy at the time. Never checked the thermostat but I figured after this being the 3rd one I'm prolly safe. Next I'm going to purchase a chiiivy sb pulley. I had one in my shop and measured it to come out at 5.75". I like that number so I'm gonna get one of those with the dual belt and also make my alt a dual belt. If this doens't cure my problem after the hot weather comes next summer, I'm quitting and buying a chiivy. Ok maybe thats a little irrational but I'm fed up and this has got to be it!! I wish some of you guys could see whta I'm dealing with and do all the tests for yourself b/c for 2 ASE certified mechanics, they all pass with flying colors. Except the massive pulley. Quite frustrating.

 

I've be wondering if you switched from a 6.? or 7inch balancer damper to a 7.5 that would turn the water pump slower. Maybe something to think about..Has the cooling system ever been back flushed be a Radi-shop?? Have you calibrated your temp gauge a so you really know what is happening?? my 2 cents
orich

 

The water pump pulley and damper pulley on my 390 were the same diameter.

If I'm reading it right, do you actually have a water pump pulley that's BIGGER than the damper pulley?

 

I have yet to pull my pulley off to measure. I have pics in my gallery of the pulley coming real close to the crank. Check it out. I'm gonna pull it off either tomorrow or thursday to install that chiivy pulley.

 

From this pic, it looks like the water pump pulley is much larger than the crank/damper pulley... but it could be an illusion.

 

I've heard tell that too thick a radiator, ie 4 rows, can be detrimental to cooling, because the rear tubes never see cool air. The air is already very hot by the time it gets past the front three rows, and thus the rear tubes become a bypass for hot water to just recirculate continually.

Driving along you'd get plenty of cool air over the whole rad, but at idle and slow driving speeds you just have the little amount sucked by the fan.

 

I doubt that very much. Besides if that were ture, then just use a fan that moves more air. A 7 blade works real well.

 

This is why I have a 5 row stagger tube radiator.