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1969 Chevy 350 Serpentine Belt System: Upper Radiator Hose Keeps Blowing Off?

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#2 ·
By goose neck, do you mean the thermostat housing? Haven't heard of that issue, but maybe some gorilla snot would keep it still. GS is a stringy yellow rubber cement made by 3M.
 
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#6 ·
Depends on the serpentine conversion you used. Some like March make a kit that specifically use/retain the standard rotation water pump. Others, like most if not all OE GM systems, use a water pump that is reverse rotation.

Good info in this Team Chevlle thread:

http://www.chevelles.com/forums/showthread.php?t=80647
 
#9 ·
Use the water pump from the caprice....? I think the 91 still will bolt up...wait...grab those heads while your at it! Arent they the same heads as the L98?!
Help me out here...
 
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#10 ·
So if your running the stock serpintine pully system off the 91 then you need to use a reverse rotation pump. That said, if you are running a short leg water pump you will have to find one at one of the specailty after market suppliers. Like Summit or Jegs. If your using a long leg pump that most all small blocks have used sinse 1969 you need to get a pump for a later model such as the 91 you got the pulleys off of.
 
#12 ·
If you're using the fan from the 91 Caprice, look at the fan blades and imagine the rotation direction needed to pull air through the radiator from the front of the car.

As said, if the fan is a reverse rotation, CCW from the front of the car, you need to get the water pump from the 91 Caprice. A reverse rotation pump.

What is happening is the pressure buildup from the reversed flow at the thermostat housing. Its dead heading and pops off the hose at the housing.
 
#13 ·
Everett#2390 said:
What is happening is the pressure buildup from the reversed flow at the thermostat housing. Its dead heading and pops off the hose at the housing.
Click to expand...
Re: reverse pumps...I thought flow was still same direction. Just impeller fins pointed other way. I've never seen one though.

If the thermo hsg is still on top and goes to rad top, and the bottom rad hose still enters at pump suction, then flow is still same direction.

What I'm saying is, a standard rotation pump spinning backwards moves no water, or next to no water. The pressure buildup would not be from flow direction, it would be from heat buildup and you would not necessarily have to show heat on a gauge to overheat. And a reverse rotation pump still sucks and blows from the same ports. A reverse rotating standard pump moves no water.

Try to say it a different way thinking out loud. Turning the pump backwards won't make it suck from the discharge(block)side and push into the bottom of the radiator. If it did pump it would be so inefficient it could not build pressure. You would be sucking with the tips of the impeller fins and discharging against the impeller to housing clearances.

The pressure buildup is because the thermostat opens and water CANNOT flow because the pump is acting as a check valve. Yup, that's how it is. The hot water wants to thermo-syphon thru the radiator, and the pump turning the wrong way won't let it. My nickel.

============================
edit: thermosyphon is a cooling system that requires no pump. The act of heating and cooling the water creates flow. Heat rises and cold goes down, they never try to argue that law of nature. Pictures available, I think I may have some somewhere in this damn computer.
 
#14 ·
All right, Tim. I pay you your nickel.
But, a std rot pump will pump something spinning reverse, but as you said, not much. I do like your thermosyphon, last ditch effort on nuclear reactor cooling after the first three back-up systems fail.

Agree, can't argue with Physics, heat rises. We have a solid state DC-to-DC power convertor water-chilled on the secondary loop, typ 85*F inlet water. Ships chilled water on primary loop, 40*F. DC tray condensates when unit is off, no pump. Ships Force come in turns on PA, smoke escapes the cabinet vents, condensate is on the connector, 300 VDC, or trying, don't mix. Other thick papered engrs ask why, pump is off, shouldn't happen. Me, with my diploma from School Of Hard Knocks, says "Heat rises." They reply "Oh man, expensive re-design." I say, "No its not, have the crew turn on the pump 24 hrs before operation, pump shear will heat the coolant and evaporate the condensate." "Problem goes away." The customer loved it.
 
#15 ·
Aw Ev, you don't owe me no stinking nickel. That's not what I meant:sad:. I just felt like it was better than 2 cents worth was why I said that:)

Your water chilled system and the smoke out of cabinet vents etc when attempting to defy nature reminds me of a project I was on one time where we had 2 little V-16's they were doing some waste heat recovery with.
They decided to comingle the exhaust. We warned them. They argued and did it anyhow. First time one engine went down it filled with water from the exhaust side. If heat goes up....Cold goes down...when you cool a gas the pressure drops...:D

An 8 foot long V-16 with pure straight water pouring out the breathers convinces folks to don't mess with mutha nature.
 
Discussion starter · #17 ·
after hearing all the input i am going to put the water pump from the 91 caprice on. the only problem is now is it doesnt have the heater hose fitting at the top. can this heater hose be moved some where else? the radiator is not a option because it has the plastic tanks.
 
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