GeorgeR_Zed06

What is the best way to tell if my HX pump is moving the fluid? When I look at the factory reservoir, I cannot see any fluid moving around. When I squeeze the hoses, it feels like it might be moving a little fluid but then again it's kinda hard to tell.

MrBlackZ06

HX pump will move the fluid at its maximum power under WOT when the supercharger is fully functional. I use the dash logic unit and I can see IAT2 temp drops immediately at WOT.

Warp Factor

Isn't the intercooler pump supposed to be running any time the engine is running?

MrBlackZ06

According to my modest information and personal experience, either the pump does not run during idle and normal driving, or it runs at a slow speed.

I have seen a significant IAT2 temps while idling for a long period, and it keeps rising as idle time goes on.

Warp Factor

Are you sure your IAT2 is a measurement taken after the cooling bricks? From what I've read, most IAT2s on our cars are not, and "Manifold Air Temperature" is what you'd be looking for.

MrBlackZ06

ِِActually I am not sure whether it is measured before or after the bricks. I believe IAT2 temp is supposed to be the temperature of the compressed air going to the intake valves. I could be wrong.

383vett

I have an aftermarket expansion tank. With the filer cap open, the water circulates anytime the engine is running. The pump is not pulse width modulated. It runs at one speed.

GeorgeR_Zed06

That's what I was thinking, so how come the fluid in the factory reservoir doesn't show any fluid movement, even after some spirited driving,,?

Does anyone still have the factory setup that doesn't mind looking at their reservoir after some driving to see if the fluid is stagnant or if you can see it moving through there?? Thanks,

383vett

Bill Dearborn

When I read the FSM they talk about 3 IAT sensors. The FSM says IAT1 Sensor, IAT2 Sensor, Humidity Sensor, MAF Sensor and BARO Sensor are all integrated together with the multifunction intake air sensor. That module is identified as B75C in the schematics and is common to both the LT1 and LT4. I think that means IAT2 isn't the manifold air temperature.

For the LT4 the schematics identify module B65 as the Intake Manifold Pressure and Air Temperature Sensor and it is a different module than the one the LT1 uses.

The Supercharger Air Outlet Pressure Sensor (B65) is located at the driver's side rear of the supercharger housing. I don't know how you measure IAT3 since you need a PID for the data logger to track it.

Bill

Warp Factor

Fired mine up in the garage just now (the weather here isn't suitable for driving right now), and there was no noticeable turbulence in my factory tank. So I expect that's normal. Maybe someone else knows a simple way to check that the circulation pump is working at full capacity?

GeorgeR_Zed06

Thanks guys, I'll just keep monitoring it and probably slap in an aftermarket expansion tank.

8850

Not sure which IAT this refers to but the pump comes on at 104*F.

GeorgeR_Zed06

Thanks for that bit of info, that might be why I don't see any activity, it isn't hot enough yet. Next time I'll go run the **** out of it then check circulation.

Warp Factor

Took my car out after the garage test, and still couldn't see any turbulence in the tank with an engine coolant temp of 186 degrees. But intake temp, measured at the MAF, wouldn't have come anywhere close to 104, with the outside temperature of 36 degrees.

I'll try to check things out more thoroughly at Spring Mountain in Nevada next week. The forecast there is calling for high temps in the low 90s. Wouldn't be a big deal to look at the tank after some semi-hard use, in semi-high temperatures.

ronsc1985

If you are just trying to see if the pump is capable of working you can,with the engine off, apply 12 volts to the left side of the pump fuse. You will hear the pump come on and you can feel the water circulating in any of the connecting hoses. I don't remember which fuse it is but there are several threads about this on the forum. I seem to remember fuse 45 but I wouldm't bet any money on my recollection being correct.

Warp Factor

I wouldn't expect to feel anything in the hoses, unless trapped air creates turbulence above normal non-air-entrained fluid flow.

ronsc1985

As with any flow in a tube you can usually feel some vibration simply from the fluid to hose id friction.

I have done this when I used the tube over the fill spout method and a vacuum pump to get as much air out of the system as possible.

Did I get any air out? Maybe but since there wasn't all that much to begin with I'm not really sure how much came out and how much was possibly leaking back in around the hose to spout connection.

MCK_Z06

Yeah, I don't think you can see it pumping by viewing the tank.
First the intercooler system only operates at around 5psi and second I think the last time I looked the intercooler tank return line is the lower hose on the tank. (I think the pump actually "pulls" from the bricks and "pushes" to the factory tank.)

I'm going off the top of my head so take with a grain of salt.

8850

Here's a video of my pump running via my HP Tuner controls.

You can definitely feel it running when holding the hoses, you can hear the pump running and see it running into the reservoir.

https://www.youtube.com/watch?v=CPqq...ature=youtu.be