On my 96 N/A.....I have single stat and the lower flow water pump I'm sure.
I have the 2 fans on condenser .....the motor in general runs good and cool most of the time,
But if I head uphill for a bit she wants to get warm, (220 steady)
Basically any semi cheaper cooling methods? Or best to upgrade pump in future?
Rads new (well recored) ,fluids new, stats new, heater cores new, water valve new,I find the
Condenser fans don't help engine coolness, more so helps keep A/C get nice and cold.
But one day I want to do loooooong trip, threw AB rockies , and lol don't wanna be stuck in Banff
National park, on the side of road,hehe
I'm expecting the slow ride uphill , but lol I will want bare-able temps in engine,
Basically picking you brain for any cooling advice.
Some times I wonder if possible to add a rad fan from upside down on rad,.?
H1 cooling ?
- Monk
- CHC Trail SuperGuide
- Posts: 1232
- Joined: Mon Oct 01, 2012 10:36 am
- Location: Ontario
H1 cooling ?
Last edited by Monk on Wed Jun 03, 2015 10:30 pm, edited 1 time in total.
96 HMC4
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
- GreenMeanie
- CHC Pilot
- Posts: 426
- Joined: Tue Jul 22, 2008 3:28 am
Re: H1 cooling ?
For up in the mountains the 6.5 will have a tough time making speed and keeping cool due to the lower air pressure and oxygen for the air charge. Fuel pressure will drop a few psi as well which can be a problem if you are using a weak stock fuel pump that only makes a few psi normally.
So,, cooling the air charge and raising fuel pressure can compensate for what could otherwise be a slow crawl up hills.
Water injection or intercooler. Water would be cheaper to install and would get the air charge a little more dense in higher altitudes.
Fuel pressure regulation will take care of a bunch of running issues. I run at various fuel pressures depending on driving condition.
I am in the process of building a water setup. Got the tanks lines installed and i am designing a Arduino controlled manifold to control the spray pulse width. Still lots to do on it so i don't know if i will get it done this year but that is my plan.
Also noted you are not running a turbo and that will slown things down a bit as well.
So,, cooling the air charge and raising fuel pressure can compensate for what could otherwise be a slow crawl up hills.
Water injection or intercooler. Water would be cheaper to install and would get the air charge a little more dense in higher altitudes.
Fuel pressure regulation will take care of a bunch of running issues. I run at various fuel pressures depending on driving condition.
I am in the process of building a water setup. Got the tanks lines installed and i am designing a Arduino controlled manifold to control the spray pulse width. Still lots to do on it so i don't know if i will get it done this year but that is my plan.
Also noted you are not running a turbo and that will slown things down a bit as well.
Last edited by GreenMeanie on Thu Jun 04, 2015 8:05 pm, edited 1 time in total.
Early 1997 HMC4, 1 of 35, Original Block H296, 110,000 miles and no cracks yet, G10 green
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
Custom made Brush Gaurd, Roof Rack, Overhead Console and Sound System.
- Roy
- CHC Trail SuperGuide
- Posts: 1933
- Joined: Tue Dec 29, 2009 8:21 pm
- Location: Stratford,Ontario
Re: H1 cooling ?
Water/methanol injection will help with engine cooling and added power. TC noticed a large cooling temperature drop with this system.I run the same on the 5.9. Greatly increased my power-no lagging uphill. Its a simple system but has good results.I have a kit in stock ,or www.snowperformance.net
99 Wagon
5.9 Cummins 12 valve mech. Stocking most parts to fix your H1
41.5-13.5 R16.5 Pitbull Rockers,
Auburn lockers front and rear
Full custom underbody protection
3" body lift
4" side rock tubes
12100 rear cv shafts
5.9 Cummins 12 valve mech. Stocking most parts to fix your H1

41.5-13.5 R16.5 Pitbull Rockers,
Auburn lockers front and rear
Full custom underbody protection
3" body lift
4" side rock tubes
12100 rear cv shafts
519-272-1761 
<p style="text-align:center;"> 
- whitehumh2
- CHC Trail SuperGuide
- Posts: 4529
- Joined: Tue Jul 04, 2006 11:47 pm
- Location: Lachine, Quebec
Re: H1 cooling ?
Evans Waterless coolant also helps!!!
And you could always install the High flow pump and dual thermostat housing!
And you could always install the High flow pump and dual thermostat housing!
<p class="bbc_center">1 - There is a time for everything,
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
and a season for every activity under the heavens:
3b - a time to tear down and a time to build,
5 - a time to scatter stones and a time to gather them,
Ecclesiastes 3:1,3b&5a
- ddgermann
- CHC Pilot
- Posts: 299
- Joined: Sat Jun 15, 2013 11:07 pm
- Location: Edmonton
Re: H1 cooling ?
I dont Know if you took your trip through the Rockies yet but I do it every year for a side by side trip to Valemount BC in the middle of summer. Overheating has never been a problem pulling my trailer with a 1500 pound Polaris Highlifter on it. I have the 6.5 Turbo and true I am definitely not passing anyone but it it shifts down when it needs to and holds 95-100 kph on all the hills. I am running at just over 2000 RPM in 4th at 100 kph and about 2700ish when shifted down to 3rd to pull the bigger or longer hills. This is on some hot days as well so I am not sure how your NA would pull... but whats the rush right? If you can figure out your cooling issue I highly recommend a trip through the mountains with your H1. There are even tons of wide easy trails you can legally take your truck on as well. Canoe mountain you can easily and again..legally climb right to the top (8800') and look down over the highway and town of Valemount. One thing to be aware of driving your H1 through the mountains.... you become very popular at stops as you are now part of the scenery.
all the best.
all the best.
1999 H1 HMC4 (black on black)
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
Hummer: from The Century Dictionary and Cyclopedia. n.[font=inherit;font-size:.9em;font-style:inherit;font-weight:inherit] "One who, or that which excels in any quality, especially in general energy or speed."[/font]
- drm
- CHC Navigator
- Posts: 92
- Joined: Mon Aug 08, 2011 9:07 am
Re: H1 cooling ?
FYI. Most importantly how old is your rad ? There are different qualities of copper recores if you go that way. My copper recore is 40% more efficient than the factory rad. update your water pump and thermostat. check and/or update your clutch fan. Buy REDLINE water wetter for diesel engines. This magic liquid can make your truck run up to 20 F cooler. I swear buy it. Checkout their website. I also swear buy GMs rad flush to clean the cooling system.
- Monk
- CHC Trail SuperGuide
- Posts: 1232
- Joined: Mon Oct 01, 2012 10:36 am
- Location: Ontario
Re: H1 cooling ?
Kinda funny that "redline " must have a cult following, soooooo many swear by it
I guess if actually works , why not.
Everything cooling wise I replaced last year (even re-core rad) and new heater core, lol I went over board, but now know alls new.
Only thing I haven't touched (but will do in fall is a new HO water pump)
Currently working on a custom turbo set up,, I'm sure after it in, it'll be months to set up.
Few peeps I know here are running holset on 6.5s,, and one 6.2 guy, soooo when in Rome :-) hehe
I guess if actually works , why not.
Everything cooling wise I replaced last year (even re-core rad) and new heater core, lol I went over board, but now know alls new.
Only thing I haven't touched (but will do in fall is a new HO water pump)
Currently working on a custom turbo set up,, I'm sure after it in, it'll be months to set up.
Few peeps I know here are running holset on 6.5s,, and one 6.2 guy, soooo when in Rome :-) hehe
Last edited by Monk on Sat Aug 22, 2015 4:15 pm, edited 1 time in total.
96 HMC4
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5
Optimizer N/A
Super Swamper IROKS 39.5x13.5x 16.5