Have 1 more for you guys

[max57]

They do offer the water pump you say you bought with the housing, but the part number I listed is the OEM version with the plastic impeller and the housing also. It is not just a cast impeller pump with a housing. It is also made in Japan instead of China like the cast impeller pump. It is a much higher quality pump.

I got Welded water pump this morning and has china on it, with Plastic impeller. I will give it a try with a relief , will do some pressure tests tomorrow at pump and at block on heater hose and see what I have for pressure at different RPMs. Then relieve it where needed. Thanks Josh.

 

[max57]

Put a gauge at water pump before oil cooler, when Thermostats are closed, Heater return on , runs 30psi 2000 rpm, 40psi 3000 rpm and seen it go higher at more rpm's And at the same time have a gauge in the heater return line and was getting as high as 20 psi.
Hot with thermostats open 20 psi 3000 rpms , 0 heater return.
guess I will relieve it at around 20 Psi and try it.
If I stop the heater return flow builds even higher numbers, lesson learned it needs the heater return flowing all the time and needs a relief at the pump as you all said.And Electric pumps do not flow enough or have head pressure all to keep water around the cylinder and heads.
Josh you nailed it. They are both Ac Delco's but Ac Delco in car is China made and New Pump with Housing is from Japan that I have on the shelf ready to go in .
I now have no water pushing out of the Radiator when I get on it. Thanks again Guys.

 

[Chevy1925]

That’s awesome! Glad I was wrong!

 

[TheBac]

Excellent information. Thank you.

 

[max57]

So little update on what I went with. First off I have a 2006 van setup in the car. They have a lower hose that the heater return and surge tank hook in the same Tee in the lower hose, so I bought a PPE 119025200 Hose for a truck setup so the heater return goes over near the water pump and the tank is hooked in need radiator outlet. Now I get no water surge into the surge tank.
I still have the China ac delco water pump in, But new Japan ac delco on the shelf. I drilled and Tapped 3/4''NPT in the water pump housing near the outlet going to the oil cooler. Put in a releif valve (Cash Acme Model # 09564-0125LF) set at 25psi , i got it at pumbing supply and run a10an fittings and hose up to the thermostat housing. Seems to relieve very well on the pressure that builds while thermostats are closed.
I also took out the check balls on the thermostat and drilled a third hole so it can bypass some pressure as well, but I have to drive 8-10 miles on 80 degree day before i see 177 degrees when the therms open. So probably should not drill the third hole if you want it to warm up quicker.
I can now kick the twins in the A and see no surge in temperature at all . Its a pleasure to drive now that it is staying so cool. So far 6 big hold her to the floor 4000 rpms runs and pump impeller is still on!!
Thanks for all the help guys.

 

[JoshH]

Awesome! Thanks for updating with your fix.

 

[Bdsankey]

Really curious as this seems like a coolant bypass for ~$100!

 

[max57]

Heres some Pics, Tapped the housing at 45 degrees on the 90 degree bend, Thanks again guys. also anyone running the aftermarket valve Covers with no oil seperator on them, WCfab helped me out by telling me to go to a 12an hose size and angle them up and no more blow by oil now. Creates less pressure in the hose.

 

[max57]

Really curious as this seems like a coolant bypass for ~$100!

A little update, Relief working good, but when set to 25-30 psi its screw is backed all the way out and turns easy so i used a ***** punch and restricted it. That did not do it, it came out going down the road, only leaks when bypassing so did not lose a lot of antifreeze. I Found the screw laying in the road, put it back in , this time i put a clamp on it so it can not turn and all is well again.