Gfrepddy coolant problem

[bigeZ]

I have a GFreddy intake on my Rb25det and i cant seem to find the Coolant Air Release Plug. I cant seem to get any collant flowing. Water pump and thermistat are new and good. I think i need to bleed the air out.

 

Could somebody that has the GReady or GFready please let me know how they bleed the collant system

Ive read about lifting the front of the car up in the air to bleed it. Does this work??

 

When i got the motor the intake was already on it. Maybe the hoses are installed incorectly.

Does anybody have the GReady paper that showes where the hoses all go.

Edited September 30, 2010 by bigeZ

[bigeZ]

I still have no water flowing through my motor. Don't know why.

 

I found this hose tucked away in the back of the motor. I assume it’s for bleeding the air out of the system

It connects to a T fitting and continues to the back of the block and the other end goes to the large tube next to the thermostat.

I tried to bleed the system through the hose by removing the plug but still no flow. Then I poured coolant into the hose until coolant was flowing out of the radiator cap opening.

This also resulted in no coolant flow.

 

When I got to the car today I was shocked when I saw the lower radiator hose (the one going into the thermostat) was completely collapsed. The radiator cap was hard to remove because of all the negative pressure. When I did finally get it off the hose expanded and filled with coolant. WEIRD!!!

 

I topped off the radiator again and still no flow.

 

I pulled the upper radiator hose off and cranked the motor over several times with the starter to see if anything would come out and I got nothing.

Shouldn’t there be water pumping out of the upper hose???

 

Pump is new and I tested the thermostat before I installed it. Wobbly thingy up and all.

 

Would having air in the system cause this problem???

[gmac708]

More familiar with the RB26 but it looks like...That big hose on the "T" on the back of the block should go to the car heater. My guess is (can't see in photo) that it is now hooked up to where the other hose that used to go to the heater used to connect (you described as large tube next to thermostat). My guess is that the heater has been bypassed by connecting the two fittings together. This will cause the water to circulate around internally. This is not good. The heater water system normally bypasses the thermostat and gets it's heated water ASAP but should not be left wide open. Your water pump is probably sucking heated water back in from that "T", and not from the radiator (path of least resistance)

 

Just a guess... for troublshooting purposes only, try to plug or block that hose by clamping it shut (vise grips). This should cause the water pump to draw the water from radiator after thermostat opens and not from the back of the block.

 

That other small line on the back that is plugged used to hook up to old intake manifold and most likely has a corresponding plugged line up front.

 

Just a guess.

 

Gord

[bigeZ]

Yes the heater has been bypassed by connecting the 2 hoses that normally go to the heater together.

I see how this could be a problem with circulation but there should still be some water flowing threw the radiator,

even if its a small amount. I'm not getting any flow at all, nothing comes out of the upper radiator hose when its removed and turned.

 

Is there a correct way to bypass the heater core??

And why would this cause the lower radiator hose to collapse in on it self???

 

I think something is blocking the water way in between the pump and the exit on the intake.

 

Ive already removed the pump and I'm thinking about shoving a water hose in a couple of the coolant passages and see if there is any blockage.

[rayaapp2]

installing the Greddy or Freddy knock off intakes eliminates the need for the water bleed. The stock manifold brings the water passages up above the fill neck on the radiator leaving the air bubble that needs to be purged. The GReddy and knock-offs drop the water passages below the filler neck especially when installed into a Z like yours.

 

When I did mine I did have to turn the heater on to purge the air past the heater control valve under the dash, but if that is all bypassed you would not have that issue. I would just cap off both heater lines in this case. Same reasons as gmac708 described in his answer.

 

As far as the collapsed lower hose goes, I can only speculate that you have an issue with your radiator cap. As your engine heats up the coolant the coolant expands and act as hydrolic pressure on the cap until it overflows the expanded coolant, but only to a point. The cap is designed to use the vacuum that forms as the coolant cools off and contracts to suck in coolant from the over flow bottle. You may say hey I dont have a coolant bottle, but you do have a cap that is designed for one unless your running one of the original caps that came on the Datsun somehow. So the secondary valve in the radiator cap isnt working as designed and is holding vacuum instead of releasing(just seems like the wrong word) it. In your case it should be sucking air to fill the void as the coolant cools and contracts, but its not. I doubt it has anything to do with water pump and a clog. The OE pump wont collapse a good hose. It will sooner cavitate.

 

 

You have not accurately enough described your situation.

Why do you suspect a no flow situation?

Are you having an over heating problem?

What kind of radiator are you running?

When you tested flow on the upper radiator hose was the engine fully warmed up? Was it cold? How are you testing for flow exactly? With the hose taken off cold? an easy diy flow test can be done by removing the radiator cap, warming the engine until operating temp, hold the revs up to 1500-2000, and you should see the coolant get turbulent.

For the collapsed hose was it as I described warmed up then cooled down. "When I got to the car today" thinking it was cold when you got to it correct?

 

 

BTW there is a GReddy intake manifold write up here on HybridZ with pictures. I used it to install my intake. Was lacking in a few areas, but will do the trick for what you need. Use the "SEARCH" feature to find it.