94 GQ Coil Cab

[Dasa]

Some old posts from other threads.

Reversing camera install
Modified fridge slide to tilt and fit camper.
Slapped together a battery box.
Replaced handbrake cable

[Dasa]

First trip since making the upgrades went well.
Just a hours drive out to where we have some cattle on agistment near Bendigo.

Boost seems to be topping out a little lower at 12PSI down from 13-14 and EGT topped out around 250c while engine temps were nice and low as expected considering how cold the weather was.
Fuel use is looking to be good so far which was the main reason for the lift pump to fix fuel use going from ~12l to ~20l after a tank of fuel on a new fuel filter.
Need to see if waste gate adjustment can get the boost closer to 15PSI or if it just needs the fuel screw on the pump wound out which is currently at the lowest setting.
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[Dasa]

High flow pump and thermostat housing sprung a leak so blanked it out and set about installing a Davis Craig EWP150 kit I picked up a few years ago.
Unfortunately I cracked the thermostat housing.
Will hopefully find a bung for the old heater return tomorrow.
Still need to find some thermo fans.
Moved the thermostat spring so it stays open and holds the bypass shut then drilled some holes to reduce the restriction.
Bashed out the old pump bearings and cut out a sheet of stainless steel to sandwich between the pump housing and the block to blank it out.
Purchased some shorter belts for the alternator and power steering.
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[PeeBee]

Good luck with the EWP150 pump. I purchased one for a chiller system and found it flowed at 3LPM when connected to the system. As a free flow outlet I have no doubts it will shift 150LPM, but within a pressure loop, a dead failure. I sent mine back to Davis Craig and they accepted the warranty claim, without comment. I was running a calibrated flowmeter in the cooling system. I have tried a number of different DC pumps and found they simply dont match their capacity claims. I have shifted to bronze positive displacement gear pumps and they pump without fail to their pump curves.

[Dasa]

Good point on the pumps head pressure, looks like its 5.1M max. Anyone know the head pressure for the stock pump or one of the high flow pumps?
It does seem to flow through the block ok at 6v when I was filling it up so hopefully at 12v it will flow well enough when the engine is under load.

So far I have driven around town and with no fans it topped out under 80c so the pump hasn't fully ramped up yet.
Tomorrow I will be driving from Bega to Pambula along the highway with a few hills so should be a decent test.
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[PeeBee]

Looks like it is performing and you cant dispute the physical data you have. I dont have the specs on the existing mechanical pump, maybe its in the manual? I have not seen anyone put a pressure tapping into the water circuit either, however the pressure rating will be aligned with the cap rating on the radiator, at temperature. Keen to hear how this works out, good job.

[Dasa]

The pump sucks from the rad cap side so if anything it's decreasing pressure on it. The cap is just dealing with the pressure from the expansion of the water and is typically rated for under 16psi while the pump bursts at over 70 psi but can only pump up to 7.2psi.

Anyway it made it to Pambula and back while staying under 85c and the temperature gauge was around 1/4 to 1/3 vs the usual 1/2 to 3/4. So it's running better than the rusty old high flo pump with a warn out housing but i also hosed out the rad and condensor which could be what's helping most.

I think I will change the pump settings so that it doesn't ramp up to full speed till 100c vs the default 85c and see how it goes.

[PeeBee]

The pump sucks from the rad cap side so if anything it's decreasing pressure on it. The cap is just dealing with the pressure from the expansion of the water and is typically rated for under 16psi while the pump bursts at over 70 psi but can only pump up to 7.2psi.

Anyway it made it to Pambula and back while staying under 85c and the temperature gauge was around 1/4 to 1/3 vs the usual 1/2 to 3/4. So it's running better than the rusty old high flo pump with a warn out housing but i also hosed out the rad and condensor which could be what's helping most.

I think I will change the pump settings so that it doesn't ramp up to full speed till 100c vs the default 85c and see how it goes.

Good feedback, certainly sounds like it is working for you, maybe I did something wrong with my set-up? I like the idea of the ramping as you can limit cavitation also. What thermostats are you running? I thought the TD42 units were the 88 Deg C units? One thing though is the comment of 7.2 PSI max output. This will have an impact on the upper limit of the water temperature before boiling. I guess you will find the tipping point in time.

[PeeBee]

Quick question, how is the water circuit actually plumbed up with the inclusion of the electric unit - do you just remove the impeller and bolt the case back together? Or is the impeller still some of the work in the mechanical pump?

[Dasa]

Removed the impeller and put a sheet of stainless in the middle of what was the pump. Installed the new pump inline on the rad outlet.
No idea what thermostat I was running but yes it was probably also raising the minimum temp.