TD42 water pumps... what would you be prepared to pay

[Bigcol]

I had the hi flow water pump in my TD42
when I did the cooling system up in Jan this year, I replaced it with a genuine Nissan one

biggest problem I was having was, when the EGT's went over 450* (while towing) the water temp would sky rocket up past 110* (alarm goes off at 110*)

since doing the complete cooling system it has not gotten hotter than 105* when the EGT's are up to 450
and the temp drops back to 95*-ish when the EGTs drop back to 300*

I had the thermostat replaced - was not quite right
thermostat housing
water pump - Mr Nissan original (water flow was no better with the "hi flow" water pump, but wanted to see the difference with OEM gear)
Viscus fan hub - was cactii
fan - was small cracks, so may as well while there to replace it
all hoses - mine were getting soft
all belts - they were looking old.......
back flush, and pressure cleaned outside of Rad - was new Dec2013 - lots of dirt and crap in the outside of it
re-filled with Mr Nissan coolant

for once I am happy with the cooling system on my TD42

[nissannewby]

Where do you do the machining??

Machine the housing. The face the gasket seals on. Measure it all up prior and make sure you take into consideration the gasket thickness.

[MudRunnerTD]

. Snipp
I wish more gq owners used accurate temp gauges to compare with... i run a good digital job and find it much better than the dodge factory one.

Mate I reckon that's actually your biggest problem to be honest. You were concerned about seeing 90 on your gauge on the snow trip. No one else was bothered at all. Your Nissan gauge would have shown very little change and everything you were running was well within spec.

Your engine will take 100 any day, and all day mate. Mine runs around at just under 90 but sees a rise on big hills. I vote for replacing your radiator and going for a drive. You are letting your water Temp gauge smash your head in mate.

Matty is suggesting having the face of the pump housing machined off by upto 3mm to bring the impeller closed to the block to restrict blowby on the water pump. I run a Nissan Pump on my GQ, when it sh1t itself I replaced it with another Nissan one. Decent coolant will happily run at 110 safely, that's the point of not using Water to lift the boiling point and allow safe operation on your engine at its upper limit.

My2c.

[mudski]

I went to JPC's this arvo mate. And when I got there, whatshisface and Mark were actually talking about your truck. The conclusion was, the 100c temps are not an issue, the mounting of the radiator was, as you knew. Both said to sort that out, and the radiator leaking and take it from there. I forgot to ask Mark about that water rail too, but I did see it on the dual cab TD they were working on.

[nissannewby]

85-90 degree is perfect. 110 is probably the upper limit.

Water rail has no real benefit on a road car. Waste of an exercise unless your racing it, even then its not really necesary. Many 180+rwkw patrols running around without an issue.

[Bloodyaussie]

My car sits between 70-82 for normal driving this time of year (very cold winter) and on the highway averages 85.

I noticed a change not long ago and had worries but as it turns out it was the radiator starting to fail so i will get a proper radiator today (should be ready) and see how it goes after that.

[moonie]

stock motor only needs a stock water pump but have seen the pumps from patrolapart looks ok but carnt go past a stock pump $$$

[Robo]

Use a genuine one. Machine it so there is less clearance on the impeller. Have seen 3mm taken out to get the clearance at a respectable gap. Dont waste your money on those "performance" pumps.

You can get a new genuine one landed for about $70.

So what would respectable gap measure?.
I assume your measuring the impeller edge to mounting face of new pump,
+new gasket into account also?.
or are we doing depth readings on case also?.

[nissannewby]

O.5-1mm. Depth readings on case also mate. So measure both impeller protrusion from housing and case depth and make your adjustments from there.

[Robo]

O.5-1mm. Depth readings on case also mate. So measure both impeller protrusion from housing and case depth and make your adjustments from there.

no wonder they suffer cavatation at 3mm if .5-1mm is the go.
the improvement .5mm gap maybe like putting in a hi flow thermostat , so to speak.