Cooling problem

[Bob Stoeger]

Ha All,
Would anyone have a drawing or sketch of a cooling system that uses an inline electric water pump. I'm using a Stewart water pump and I'm having some over heating issues and I would like to make sure I have it plumbed right. I've tried bleeding the system several times, changed things and nothing seams to help.
Thanks,
Bob

 

[Alex]

Is your expansion tank at the highest point in the system?

 

[Mark Clapp]

Hi Bob, if you haven't, you should consider installing bleed lines of small diameter hose (3/16-1/4" id) from the top of the radiator and a high point on your intake manifold (depending on whether your motor tilts up at the front or the back) and tee these together into your header (filler) tank. That way you will have a self-bleeding system, which should take that out of the equation.

 

[Brett James-McCall]

Do you have a sketch of how you have it set up now?

As Mark says, bleed lines. Ensure the header tank is nice and high and the fill hose is also big enough. Also, have you ensured you are pushing the fluid the correct way round the system.

Other things, what have you done with the mechanical pump? Does the SW just go full bore from start to finish, or do you have a controller on it?

 

[Mark Clapp]

Bob, another couple of thoughts. Consider the ratio of antifreeze to water in your system. A 50/50 mixture is usually reccommended for street car use but antifreeze actually holds heat so there is less dissapation. My system is about 3 gallons and since the car never sees freezing temperatures, I only use 1 gallon (30%) of antifreeze for the corrosion package. I also add a bottle of Redline WaterWetter. One other mod I made was to add a piece of plastic sheet across the "floor" of the frame in front of the radiator to help push air through the core. With the acute angle of the radiator, I suspected that air was glancing off the unit and flowing under the car as opposed to being forced through. With these mods and a stock water pump, I do not use the fans unless I'm stuck in traffic even in temps well over 90F outside.

 

[Ian Anderson]

Bob

are both the mechanical water pump and electric pump pushing the water in the same direction? (as opposed to fighting against each other?)

Ian

 

[Bob Stoeger]

Ha Guys,
Thanks for your info and I'll try to answer all the questions and comments the best I can.
Alex, Yes the expansion tank is the highest point in the system but I'm not sure if its high enough yet.
Mark, check out my sketch and see if that's what you are talking about and the ratio thing is something to look at also.
Brett, Here is the scetch of my system as it is now sorry for the crudeness of my drawing.
Ian, I have no Mech. pump I'm just using the electric pump and the housing on the motor is just an empty vessel to get water into the engine.
I hope this answers the questions for now.
Thanks,
Bob
Sorry guys my drawing wont load I'll keep trying

 

[Bob Stoeger]

Hope this works.
Bob

 

[Seymour Snerd]

Hope this works.
Bob

Two differences I see are you have no provision for bleeding air from the block (item 4 in the first diagram), and your header tanks feeds into the intake manifold rather than the water pump. (item 5)

 

[(C)arlos]

Hmmm correct me if I am wrong but the expansion tank should be connected to the line that goes from the block to the radiator....bleeding is different....I have three points for bleeding the system independently.
I start at the radiator where I have a bleeding bolt, then I bleed the manifold, the rest is done by the expansion tank ...Also I have to do it several times because I have a heater installed ( heeeee.....don't laugh this is a requirement fron the german TUEV, antifog for the windscreen .... )......

 

[Bob Stoeger]

Ha Alan,
Now I'm really confused the top picture you showed is the one I have and that one shows the bottom hose leading into the water pump housing on the engine as the inlet to the motor. the bottom picture you have is the opposite it shows the top hose leading into the block as the inlet to the motor is that right or am I looking at it wrong.
Bob

 

[Seymour Snerd]

Ha Alan,
Now I'm really confused the top picture you showed is the one I have and that one shows the bottom hose leading into the water pump housing on the engine as the inlet to the motor. the bottom picture you have is the opposite it shows the top hose leading into the block as the inlet to the motor is that right or am I looking at it wrong.
Bob

When you say "top" and "bottom" are you referring to the arrangement of the main pipes as they run through the tunnel? If so forget that, it doesn't matter.

IAE your drawing has those connections (the main coolant connections) correct. So if anything just disregard the lower (SPF) drawing. I included it only to help clarify the "smaller" connections (heater, purge/bleed, etc.). My main complaint with the top diagram is the way it shows the tank output joining the main suction line via a "tee", whereas (on my car at least) that connection is direct into a 3/8" NPT port in the body of the water pump.

If there are any issues with your diagram I think they have to do with how the tank output connects, and how you get air out of the engine. If I were to place a bet it would be that you still have air in the engine.

Also, BTW where is your fan thermostat and where is you water temp gauge sensor? On my car the fan thermostat is on the "cold" (suction) side of the radiator, and the temp sensor into a 3/8" NPT port on the intake manifold just behind the distributor.

 

[Bob Stoeger]

Ha Alan,
Thanks for the clarification on that, and my set up is close to yours but my temp gauge is off the rear of the intake instead of the front.
Would you have a sketch of what my bleeder system should look like it would be a great help.
Thanks,
Bob

 

[Seymour Snerd]

Ha Alan,
Thanks for the clarification on that, and my set up is close to yours but my temp gauge is off the rear of the intake instead of the front.
Would you have a sketch of what my bleeder system should look like it would be a great help.
Thanks,
Bob

None other than the two already posted and as far as bleeds go they say essentially the same thing.

To be specific, my SPF is connected per the bottom diagram, except for the irrelevant tunnel pipe stacking issue already noted.

There are two bleed/purge lines:

1. A narrow line running from the top LHS (cool side) of the radiator through the tunnel to the upper half of the expansion tank. (item 1 in the top drawing). Your diagram shows you already have this.
2. A narrow line running from the top front of the intake manifold (Tee-d with the heater line) to the bottom of the expansion tank (item 4 in the top drawing). One point of engine variability is that my thermostat housing aka water neck does not have a bleed connection. Otherwise I would have connected this there rather than the way I did. However, both points are the same altitude and right next to each other and my thermostat has a little hole in it so for bubble purposes they should be the same. Either way, this should be the highest point of the cooling system in the engine, that is, wherever bubbles would accumulate if there were no bleed line. So this location only works if the engine is level or tilted back. If your engine tilts forward you need to come up with a bleed opening at the back of the engine and that would vary with your particular engine and manifold. Since you have the temp gauge at the rear that could serve as your engine bleed point if it ends up being higher than the front. But one caution: if your temp gauge is sitting in a bubble it's going to indicate weird things, including non-existent overheating. So this topic, engine bleed, deserves your attention. And generally you want temp sensors immersed where the fluid is flowing well so you might want to move it to where you know the whole pump flow is going past. On an FE or Windsor I belive the tap behind the distributor is the traditional spot.

IOW, the basic principle is the GT40 cooling system is "U"-shaped and thus has two "high points": the top of the radiator and the top of the cooling system within the engine. Both of those points need to be connected to the expansion tank so bubbles can rise from each of the two high points up to the tank, and thus be replaced with coolant.

And just to double check: where's your fan thermostat? It should be on the "suction" or "cold" side of your radiator but I just wanted to make sure. If it's on the hot side it would just make the fans run too much, so it's unlikely to be the problem.

 

[Jac Mac]

Bob, If your electric pump is mounted in the front end of the car you must rethink the whole system with regard to where the coolant is being 'pushed or pulled' by the electric pump versus what happens with the standard mechanical system.

For example, you can no longer assume that the old pump fittings that were heater return or header tank return are going to be suction fittings as your 'new' pump placement will now have made them pressurized.

 

[Bob Stoeger]

Jac Mac,
How right you are that's why I was looking for a drawing of a system that someone has done with the electric water pump, and thanks for noticing the difference. All the help is greatly appreciated and will be noted but I haven't solved the problem yet.
Thanks,
Bob

 

[René]

maybe its something simple as the thermostatic valve not working correctly or mounted the wrong way...
but I don't know how it looks like in your engine/system.

 

[René]

or maybe that valve opens not wide/fast enoug, see this>>
pictures of difference in opening in same temp but different settings of that thermosstaic valve or thermostat

170° PERFORMANCE THERMOSTAT for Mustang Shelby GT500, Cobra, Lightning, GT & Mach 1 - Ford 4.6L 5.4L DOHC SOHC by Reische Performance Products

comes from this>>

170° PERFORMANCE THERMOSTAT for Mustang Shelby GT500, Boss 302, Cobra, Lightning, GT & Mach 1

maybe you have something like that?

 

[Scott]

GTrene,
Bob already modified the thermostat, so that has been ruled out. Scott

 

[Jac Mac]

Bob,

Modified your drawing.