914 Water pump, Yes a SBC Options

[drive-ability]

I'm replacing my Renegade/Chrysler BB pump, since it locked up last night. I didn't here any noise at all ? The engine does make a bit of noise but you would think there would be some warning. Nope ! Maybe something broke off and jammed up the impeller etc. The pump just locked up and melted the drive belt.
My question is I have been running a standard pump and decided to get a high volume unit. My assumption is the quality is better than my last one and with A/C it might perform better moving more water. I guess with more pressure comes it own set of issues. One thought is the belt was too tight, and that's a good bet.
I'm not running a Thermostat but am running a minor restriction in the thermostat housing, which I think I should remove.. ?

Any one have any input here. (IMG:style_emoticons/default/type.gif)

[computers4kids]

ouch
(IMG:http://www.914world.com/bbs2/uploads/post-9090-1254106903.jpg)

[drive-ability]

ouch
(IMG:http://www.914world.com/bbs2/uploads/post-9090-1254106903.jpg)

computer4Kids,
That looks just like my pump, I'm really not too worried about the situation. I went out and got a pump that uses 8 blades. Looking at its stamped design using smaller paddles my thoughts are it will handle the pressure better. I'm no expert on the subject and would like a unit with a cast impeller so I will be looking into the pump our expert SLITS pictured as a back up..
Its sure a odd way for a pump to fail but I think it goes back to the weight of the water volume acting upon the impeller blades. If it were from a single hydro event my thoughts are a hose would blow or my recovery bottle would show signs of action. Sounds reasonable to me but what the (IMG:style_emoticons/default/w00t.gif) do I know !

[computers4kids]

I would have dismissed this whole water pump incident had it not also just rececently happened to my friend Tony as well. Tony's Thread You guys should put your heads together and see what you have in common. Sorry you had to go through all this as well, but at least perhaps we can learn from it. I sure like the idea of the cast iron model. It's interesting that others have had never had problems. I know Tony has his water lines run through the longs. Other than that our systems are pretty all similar (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif)

[SLITS]

There is nothing to say other than there could have been a run of defective impellers .... it wouldn't be the first time outsourced material from our friends to the East or South didn't screw up or substituted an inferior material. Quality Control is not one of their strongpoints.

All it would take is one fin to break off and the carnage would begin. Our water pump expert insisted that it appeared there was a foreign object in the system that caused the failure or something along the lines stated above as he had not seen that happen.

At one time, rebuilders would not accept "aftermarket" cores for rebuilding due to the poor metallurgy and castings.

Draw your own conclusions ... They supply what we demand ... Cheap.

[drive-ability]

I have had some time to drive the car and have found this 8 blade pump isn't cooling the engine as well at idle speed. At this point I don't know why, there's a restrictor in the thermostat housing and I will be removing it tomorrow. Lets see if anything changes. (IMG:style_emoticons/default/beerchug.gif)

[SLITS]

8 vane moves water slower .... low rpm even slower ..... longer residence time in the engine.

Could be incorrect impeller depth for the housing.

Where are you measuring the temp?

[drive-ability]

8 vane moves water slower .... low rpm even slower ..... longer residence time in the engine.

Could be incorrect impeller depth for the housing.

Where are you measuring the temp?

I'm using a spot at the intake manifold, a few inches from the thermostat housing. (IMG:style_emoticons/default/popcorn[1].gif)

I take comfort in knowing you know what your talking about when commenting about the 8 blade pumps. LOL (IMG:style_emoticons/default/biggrin.gif)

[drive-ability]

I have found the 6 vane pumps (Chrysler 440) work better in my cooling system, but I am having trouble finding one. The two I have looked at were both 8 vane units. Anyone here able to help out.
I have posted this question in a Chrysler forum as well (IMG:style_emoticons/default/chair.gif)

[burton73]

I have found the 6 vane pumps (Chrysler 440) work better in my cooling system, but I am having trouble finding one. The two I have looked at were both 8 vane units. Anyone here able to help out.
I have posted this question in a Chrysler forum as well (IMG:style_emoticons/default/chair.gif)

Call Rod Simpson Hybrids at 310 826 3304 and ask Rod if he will sell you one.

Bob

[SLITS]

How many do you want?

Stamped steel

Cast iron.

Aluminium body

Cast iron body

[drive-ability]

How many do you want?

Stamped steel

Cast iron.

Aluminum body

Cast iron body

I used a aluminum 6 blade stamped steel unit and it worked well until it blew apart.

6 blade stamped & Cast impeller, do they flow different ?

Thanks Bob for the phone number

I wonder if I could use the 6 blade stamped unit and weld on a anti-cavitation plate ?

Can't see how that would be hard, but would it dumb down the flow ?

[SLITS]

Ok, last shot at this subject.

The man I am talking to worked with Rod Simpson on his designs and also Weiand on their designs.

One of the problems of the pumps was that they would cavitate on transition from idle to motion (starting and stopping in traffic). This would destroy the seal, but not the impeller.

Rod Simpson's problem was the diameter of the lines running to and from the radiator. Overheating was a problem due to pressure and diameter needed to push the water up and back about 6' each way and the type of radiator used. He couldn't remember what diameter line was finally finalized (work was done in the 80's)

Another problem that can occur is the RPM of the water pump which is controlled by drive pulley size. You spin a pump to fast and it will cavitate. Much work has been done on pulley size to optimize impeller speed.

Now back to the water pump itself. Cast iron or stamped steel should not make any great difference in flow, but the cast iron blades are somewhat cupped which enchances water capture (just think boat propeller). We said that the weak point on the stamped steel was the notch at the base of the blade. Some manufacturers either welded a plate on top of the fins or at least a donut to stabilize the fins. That's one fix.

Also, the fins (or the donut / plate) should be no farther away from the back housing than 1/32" (0.031"). Father away will create cavitation and lessen pumping capability.

That's about it ...... carry on .......................

[Bruce Hinds]

Sorry for the diversion, but has anyone used an electric pump on a thermostat?

[drive-ability]

(IMG:style_emoticons/default/clap56.gif) Thank You, I now understand there was allot of R&D done a long time ago. Surely there's more going on here then you might expect. I think I can use this pump for a while because it cooler here and I'm not running over 200 at any time. I would like to get the 6 blade unit installed soon. Thanks (IMG:style_emoticons/default/beerchug.gif)

[svsv]

(IMG:style_emoticons/default/clap56.gif) Thank You, I now understand there was allot of R&D done a long time ago. Surely there's more going on here then you might expect. I think I can use this pump for a while because it cooler here and I'm not running over 200 at any time. I would like to get the 6 blade unit installed soon. Thanks (IMG:style_emoticons/default/beerchug.gif)

This might be a dead topic, but cooling everything from hypo BB's to hyped up 4cyls i do know. First thing is you always run a thermostat! and you never run a pump with stamped steel impellers, unless it's to the parts store to get a cast one. magnum 440's 68 through 71 have the pump your looking for buy them from mopar parts. As far as electric pumps, your on the money with longjevity issues they are made for drag racing or last resorts.Your moving water along way through a restricted enviorment. Large as possable lines are required to reduce your pressure. Similar is rear mounted rad's on mud boggers 1.5" lines are typical on thoes installs and work fine for up to around 600hp. Good luck and I hope I was of some help.

[charliew]

One thing I remember is that a temp sensor in the intake manifold is showing about 10-15 degrees cooler than a temp sender in the head. The head is a lot better if it really is marginal on cooling. The intake temp will make you feel better though.

[burton73]

Ok, last shot at this subject.

The man I am talking to worked with Rod Simpson on his designs and also Weiand on their designs.

One of the problems of the pumps was that they would cavitate on transition from idle to motion (starting and stopping in traffic). This would destroy the seal, but not the impeller.

Rod Simpson's problem was the diameter of the lines running to and from the radiator. Overheating was a problem due to pressure and diameter needed to push the water up and back about 6' each way and the type of radiator used. He couldn't remember what diameter line was finally finalized (work was done in the 80's)

Another problem that can occur is the RPM of the water pump which is controlled by drive pulley size. You spin a pump to fast and it will cavitate. Much work has been done on pulley size to optimize impeller speed.

Now back to the water pump itself. Cast iron or stamped steel should not make any great difference in flow, but the cast iron blades are somewhat cupped which enchances water capture (just think boat propeller). We said that the weak point on the stamped steel was the notch at the base of the blade. Some manufacturers either welded a plate on top of the fins or at least a donut to stabilize the fins. That's one fix.

Also, the fins (or the donut / plate) should be no farther away from the back housing than 1/32" (0.031"). Father away will create cavitation and lessen pumping capability.

That's about it ...... carry on .......................

I am sorry that I do not remember the size of the lines for sure that Rod runs in his cars but he did say that re runs a bigger line for the cool water and a thinner line for the hot water. He said the cooler water is thicker and needs the bigger diameter to carry it and the hot will work with the smaller. He did say this was a mater of cost. I think the Hot was ¾” ID and the COLD was 7/8” ID.

Bob

[computers4kids]

Ok, last shot at this subject.

The man I am talking to worked with Rod Simpson on his designs and also Weiand on their designs.

One of the problems of the pumps was that they would cavitate on transition from idle to motion (starting and stopping in traffic). This would destroy the seal, but not the impeller.

Rod Simpson's problem was the diameter of the lines running to and from the radiator. Overheating was a problem due to pressure and diameter needed to push the water up and back about 6' each way and the type of radiator used. He couldn't remember what diameter line was finally finalized (work was done in the 80's)

Another problem that can occur is the RPM of the water pump which is controlled by drive pulley size. You spin a pump to fast and it will cavitate. Much work has been done on pulley size to optimize impeller speed.

Now back to the water pump itself. Cast iron or stamped steel should not make any great difference in flow, but the cast iron blades are somewhat cupped which enchances water capture (just think boat propeller). We said that the weak point on the stamped steel was the notch at the base of the blade. Some manufacturers either welded a plate on top of the fins or at least a donut to stabilize the fins. That's one fix.

Also, the fins (or the donut / plate) should be no farther away from the back housing than 1/32" (0.031"). Father away will create cavitation and lessen pumping capability.

That's about it ...... carry on .......................

I am sorry that I do not remember the size of the lines for sure that Rod runs in his cars but he did say that re runs a bigger line for the cool water and a thinner line for the hot water. He said the cooler water is thicker and needs the bigger diameter to carry it and the hot will work with the smaller. He did say this was a mater of cost. I think the Hot was ¾” ID and the COLD was 7/8” ID.

Bob

That's how my setup is...just followed the directions provided, but I always wondered why the different sizes... (IMG:style_emoticons/default/idea.gif)

[drive-ability]

Was thinking about a smaller pulley, so looking around I found one. Its about
4 " inch pulley, it seems to be around 2" smaller than the one I'm using now(6"). I'm hoping it will push water at idle but not cause cavitation at higher rpm. It wasn't much to adapt to fit the pump and will be interesting to see how it preforms being 33% smaller. (IMG:style_emoticons/default/idea.gif)

[charliew]

I'm not sure I follow the idea of a smaller hot water line and a bigger cold water line. Most things expand with heat and contract when cold except for water that freezes that I work with. I do have three fieros and they use at least 1.250 or 1.50 id lines to get to the front radiator. I noticed the small lines on some v8 conversions but I never planned on running any smaller than 1.250 id on my suby conversion. I think I've read where mercedes or some mfg uses a electric water pump controlled by a electric thermostat. This kinda reminds me of the guys that use to badmouth the airride stuff when we discuss the electric water pump. I know mezerie probably makes a good pump but the small lines may put to much restriction on the pumps.

I'm afraid the 33% may be too much change and the pressure will get really high at 6 or 7k. I never had any success changing the pulleys on sbc pumps.

You can gets lots of ideas here and there are probably lots of people that have fought cooling problems on hot rods. I would check on what the gt40, pantera, or the others do or any other how high performance mid engine cars work on their cooling.