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440 Fresh water cooled manifolds not cooling

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danny731

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"I'm pretty damn sure I ha

"I'm pretty damn sure I have the plumbing right, but these things are not getting cool- you can boil water on them! Luckily I have the engine in my garage so I can fix it now. The heat exchanger is getting pretty warm, so I'm guessing that coolant is circulating through the block... Does anyone have a good picture of where the coolant hoses get plumbed into the water pump housing? I went off a pic I found in a 440 rebuilding manual for the hearter core hoses, as well as some other kinda clear pics I found on line. Here's the way I got mine....

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"
 
"If I'm reading you right,

"If I'm reading you right, you have the manifolds FW cooled through the heat exchanger? If so, which exchanger are you using? For the 318's... and I assume for the 440's, a special higher capacity exchanger is required if FW cooling the manifolds. Exchanger used with engines with raw water cooled manifolds doesn't have the exchange capacity to handle the added BTU load if manifolds are plumbed into the FW loop"
 
"I am using the big tubul;ar e

"I am using the big tubul;ar exchanger on the port side of the engine (or driver side) it measures 4" by 32". I bought this from a memeber that had one on his 440, but I can't really tell from the pics he sent me if his manifolds are raw or fresh water cooled. I really want to keep them FWC as they're aluminum, and to replace the set would run me about $1200..."
 
"Some thoughts...

1. Is you

"Some thoughts...

1. Is your "raw water" supply sufficient?
2. Is the circulator pump (on the front of the engine) working properly?
3. Is the raw water pump operating properly? Maybe pull it apart to confirm the impeller is intact.

BTW, the engine looks great!
3. Is the thermostat installed properly?
4. Inspect the exchanger to be positive there are no blockages in either circuit; obstructed exchangers are a common ailment."
 
"Jim,
I've come to

"Jim,
I've come to think that maybe my engine is actually turning the wron way, it's rotating, as you look at the front, clockwise. The FIRST starter I got for it turned it counter-clockwise, and also turned the distributor clockwise, which (the dist.) is anti the the rotation I found in a Dodge rebuilding book. The raw water pump is working very well, so well that it will collapse the garden hose hooked up to it when I run it up to 4000 rpm (momentarily) but I do have plenty of flow at idle to 3000 rpm.

I am really leaning toward the circulating pump turning the opposite direction thus not providing enough flow. Hell, I wander what effect that has had on my oil flow......."
 
Did you have oil pressure when

Did you have oil pressure when you were running the engine?
Agree it's a water pump or blockage problem somewhere. Is the raw water impeller damaged? Maybe installed with the vanes flexed the wrong way? Thermostat in upside down?
 
"The raw water pump has a bran

"The raw water pump has a brand new impeller installed correctly, I believe the t-stat is in correctly, and I know there's good flow through the heat exchanger. I will take the circulating pump out to check the vane direction of that in addition to the t-stat / expansion tank.

As far as oil pressure goes, I don't know if it's correct, but I gotta brand new gage that stays pegged at 80 psi, so I don't think something is right there. I think I should take the filter off and crank the block w/o the coil connected to see which hole the oil shoots out of.

Thanks again Jim for the advice, lemme see if I can get away from the wife and kids long enough to check this thing out...."
 
"Do you have a copy of the ser

"Do you have a copy of the service manual showing the various plumbing routing configs? If not, I may have a copy I can email to you.

A thought occurred from a little clue you dropped... You mentioned that the body of the exchanger was getting warm. It should stay relatively cool considering the flow of raw water you have going through there. Check to see if the raw water is routed into the exchanger so that the engine cooling, let's call it the antifreeze loop for clarity, is in the coiled loop which is immersed in the raw water. That's how mine is set up. If it's the other way around, the cooling interface area ratio will be reversed which will limit the engine BTU handover to the raw water side."
 
"I got the cooling loop right-

"I got the cooling loop right- raw water goes in the outside port closest to the end, and comes out of the two smaller ports on the rear end.

I believe i finallt found my problem- I took off the circulating pump, and sure as sh!t, the vanes are set up so that they're trying to push water, as opposed to slinging it.

I know the engine is infact turning the correct direction because when I took the oil filter off, and had my daughter crank it w/o the coil hooked up, oil came out of the outside port, which is correct. Too bad the oil is milky- definitely blown head gaskets
but a time consuming, but easy fix. Maybe I should bolt on an Edelbrock intake while it's off. Any advice on that?"
 
"Good news on finding the prob

"Good news on finding the problem with the pump vanes! If the existing intake is in good shape, why change it out?

As far as other stuff on the engine, do you have a correct fuel pump on it? Should have a vent tube which runs to the carb air horn. Vent's there to scavenge fuel from the pump in case the diaphragm leaks. Prevents fuel from entering the crankcase. Lastly,your exchanger may use one or two pencil zincs. Might want to check if they're there.

I plan on re-building the 318 in my 22' center console Aquasport when I replace the decks. Been real interesting reading you're thread here since I plan on going to FWC manifolds as well."
 
"Jim, our 440 pumps don't

"Jim, our 440 pumps don't have an air vent, they look like a car pump.
Danny, call me and let me know what the water pump look like as I may have a correct one for you. I have never seen an option in my books to run the closed cooling thru the manifolds, does anyone else here have a diagram of this type setup?

Dan
425-785-1387"
 
"Thanks Dan, it's kinda la

"Thanks Dan, it's kinda late so I'll call in the morning. I was gonna buy one off of the ebay seller "ebasicpower" but one time I kinda told hime he's rediculous for charging $13 for a 2 ounce nuetral safety switch, so the jackass blocked me LOL. Not too smart considering I was gonna spend $80 with him. Now hopefully Dan can seel me one, or I'll go pay the same that guy was charging for one at Worst Marine...."
 
"You'd be surprised how of

"You'd be surprised how ofter impellers are installed with the vanes going the wrong way--and they don't "flip over" as some people think. (Not all of the vanes, at least.)

Had a "non-problem" as it turns out with one of my raw water pumps this week. Removed the outlet hose from the pump, aimed it at the bilge, and fired the motor up. A surprisingly mild steam of water came out, even at high idle. Why do this? It's geat way to be sure the impeller is working correctly, and it takes just a second to do.

Jeff"
 
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