Hi flow coolant pump...verses stock

[azscott]

Well got my water pump off....found that the radiator was also leaking...so gonna replace em both plus Tstat and hoses.

Question is...has anyone used the hi flow coolant pumps like Flowkooler...verses just replacing it with OEM style.

I had ordered a Flowkooler but now they are back ordered for casting and I need to get this running and really don't want to wait another week or two for a pump.

So I don't mind replcaing it with an OEM it is just that it would run very hot at idle. Certainly could be due to a other issues like a failing fan clutch..which I will replace also since I am this far into it.

I don't want to go with a cooler Tstat as the ECU is designed to have the engine run at 190. Maybe a 180 Tstat is fine but nothing lower. My engine runs best at or near 190.

Any thoughts.

scott

[Eagle]

So I don't mind replcaing it with an OEM it is just that it would run very hot at idle. Certainly could be due to a other issues like a failing fan clutch..which I will replace also since I am this far into it.

What makes you think it would run hot at idle with an OEM water pump?

 

The weak point of the XJ/MJ cooling system isn't the water pump, it's the radiator. The size is marginal. If you increase the flow rate, all that does is push the coolant through the radiator faster, so it has LESS time to shed heat to the radiator. It'll have the opposite effect of what you want to accomplish. Back when I crewed on a stock car, a lot of the drivers cut down the impeller on their water pumps precisely to reduce the flow of coolant through the radiator so it would have time to shed the heat.

 

If your system overheats at idle with a new radiator and a new water pump, you have other problems.

[azscott]

....kinda what I was thinking.....cool. I will cancel the Flowkooler and just get one from Napa.

Oh..I didn't mean that I think it will run hot at idle with a new OEM style...rather that it was currently running hot with the OEM one. I actually think the issue has little to do with the pump but...sometimes if you read enough adds...you waste money unnecessarily!!!

Thanks Eagle.

scott

[LEAD_NOT_FOLLOW]

I'm running the Hesco Hi-Flow pump and am happy with the upgrade. I see a lot of benefits with going with a hi-flow unit; a lot of it being simply a better built pump than a factory replacement.

 

 

Here is a link to my write-up; viewtopic.php?f=9&t=7695

[HOrnbrod]

Me too, and :agree:

[ratrapp]

i've got the hesco pump and high flow t-stat housing as well.they are good upgrades over stock.stick with a mopar t-stat.i've used several different brand high flow t-stats and different temps and none of them do as good a job as a mopar piece.i've had several of the supposed fail safe t-stats stick closed in less than a year.

[DirtyComanche]

The engine is supposed to run OVER 190. The factory tstat is a 198, IIRC, and I would not recommend deviating from it.

 

If it seems hot, the gauge may also be at fault. Is is naive automatically assume that a $3 gauge is actually reading with any sort of precision.

 

I've not had any real problems with the regular parts house water pumps, other than once being sold the wrong one.

[azscott]

Finally got it all replaced...T-stat, pump, radiator, hoses, belt. Temp holds fine like it should. prior it would run cool on the hiway but at idle it would jump over 210 and the fan would kick in and out...which is normal but...it would get real hot. I know the T-stat was stuck open...which is why it would run cold on the hiway...which causes me a bit of an mpg drop.

Plus the coolant system was leaking everywhere...radiator..pump...hoses...nothing huge but little weeping.

I took it out for an hour toodling around offroad in 1st gear to see if it would spike intemp like it used too and this time had no problmes. pretty muc h hold just below 210 like it should ( 195 Tstat).

I am just not a big fan of having to run a lower temp Tstat. The engine was designed to run at 195 or so.

 

Of course while doing all of this and having all the stuff ripped out I discovered a few more issues. Pretty good exhaust manifold leaks....bummer..but not an issue at the moment. Shoot...I own 2 Pathfinders and that is something you just learn to accept. On the other hand I found a leak in the intake manifold...kinda by accident...pretty sure that it is leaking. That would explain the erratic idle I have been chasing like..forever.

Plus the 3 vacuum lines that run to the shift motor were cracked..2 were completely broek off ( the green and yellow)...not sure how it shifted in and out of 4wd...or maybe it never did)...fixed those leaks. With all the vacuum leaks this thing had I surprised it could even run...no wonder why my AC keeps swapping to vent when I accelerate. Maybe NOW it will stop doing that...this is like the 10 leak I have fixed.

scott