High flow thermostat/housing

[ajmorell]

Anyone have any experience with either of these products from Hesco or in general? I have 2 thermostats sitting around and was thinking I could probably modify one myself but I don't know that it would be worth it. I do have an upgraded water pump (flowkooler) to push more fluid at low RPMs so I thought this might also help. My jeep is my DD but also a crawling rig which is what I would mainly be concerned about.

[BADASYJ]

I have seen people drill a couple holes in the T.stat before. Not to hard to do.

[ajmorell]

Okay, I'm not questioning if it can be done. Does it help? Will it make a significant difference in low RPM cooling?

[yuppiexj]

When it's cold out (15 degrees F) my XJ won't keep temp over 180 degrees, I drilled a 1/4" hole in the thermostat (to help burp the system).

[ajmorell]

I guess maybe I didn't phrase my question right. Will a thermostat/thermostat housing which can flow more gpm than stock improve low RPM cooling?

[yuppiexj]

drilled t-stat and ported housing by itself yes. I have anecdotal evidence to support this assertion. (This is what I did, bleed hole on t-stat and I hit the inside sharp 90 degree angle with a die grinder to smooth the transition). Stop and go traffic temps stay right at the 210 mark, lower if the AC is on due to the electric fan turning.)

Coupled with a flow Kooler or other high flow pump even more so.

I highly recommend grinding away on a spare thermostat housing.
see this linkhttp://www.jeepin.com/features/gdi/index.asp for pics. 7th pic down.

HTH

[ajmorell]

Sounds like I might as well try it. If I run into issues I always have another housing to put on. Where did you drill out your stock t-stat?

[yuppiexj]

Something like this http://www.cherokeeforum.com/f2/my-hot- ... post238301

I only drilled one hole, and made sure it was located at the top most (12 o'clock) position when installed.

[ajmorell]

Something like this http://www.cherokeeforum.com/f2/my-hot- ... post238301

I only drilled one hole, and made sure it was located at the top most (12 o'clock) position when installed.

Thanks. I did a little reading and have read all sort of different opinions on it. It seems a lot of guys drill two holes, 1/8"-3/16" or so and place them at 12 and 6.

[woodjeep]

For what its worth, I wish I did not drill my t-stat. I drilled out two small holes to "allow more flow". If that tstat is wide open 2 small 1/8 to 3/16 holes add almost no extra flow comparatively so no real difference. What it does do is allow a lot more flow when its cold and the stat is closed or barely open so it take me forever to warm up if its below 30 degrees. I run a high flow tstat, high flow housing and a flowkool pump. I find that airflow over that crappy radiator is much more restricted than the water flow through the engine. I have a switch that allows me to turn on the aux fan at will and in traffic if I start getting close I turn it on and the temp cools right down even with no increase in water flow

[dwg86]

Just some info on my Jeep. I am running a 180 thermostat with a stock water pump, stock thermostat housing, stock radiator, stock fan on engine, and I don't have any overheating issues.(.040 over stroker, 9.25:1 comp. 2003 TJ)

[SilverXJ]

I had a high flow water pump, high flow housing, and high flow t-stat. I found that at highway speeds it would start to over heat. I think the problem was that the water was moving too fast through the radiator to allow proper heat exchange. I didn't try any restrictors because I ended up damaging a fin on the flowkooler pump while cleaning out the head bolt holes and just replaced it with a stock pump. I wasn't fond of the flowkooler any how as it was just a stock pump with a plate riveted on the fins.

[ajmorell]

Well I think that I will see what happens with it setup the way it is now then (flowkooler, stock t-stat housing, stock t-stat). If I have no issues then I'll just leave it. I have an extra t-stat housing so it's easy enough to open that up/swap it on if I decide to later on.

[tenesu]

I had a high flow water pump, high flow housing, and high flow t-stat. I found that at highway speeds it would start to over heat. I think the problem was that the water was moving too fast through the radiator to allow proper heat exchange. I didn't try any restrictors because I ended up damaging a fin on the flowkooler pump while cleaning out the head bolt holes and just replaced it with a stock pump. I wasn't fond of the flowkooler any how as it was just a stock pump with a plate riveted on the fins.

the stock pump on one XJ's 4.0 has five fins and no plate (i would assume OE pumps are match more or less to the radiator and fan(s))... high flow pump manufactures often add more fins and a backing plate if one does not exist. I would guess the backing plate compresses coolant into a tighter space along wth extra fins increases water flow ... one objective being to increase overall cooling system pressure which is suppose to increase overall cooling efficiency

The rating on the thermostat is sometimes the cause of over heating or under cooling.

adding restrictors slows water flow and also inhibit cooling . ... i would think the pump needs to work and be matched more or less with both the radiator and fan(s) ... if the radiator needs more time to dissipate heat then the problem would most like;y be with radiator and fan efficiency ...

I am not sure but would assume some types of high-flow pump applications may require a HD radiator, perhaps a fan upgrade to compensate for the increased water flow and pressure ...

Prior to upgrading and spending $ on a high flow water pump i would want to first take a look at the radiator, hoses and fan(s) ... adding hood vents also lowers engine temps ... (too low as well as too high engine temps can cause premature failure to engine parts)

Found some balanced Robertshaw thermostats which are pre-drilled ... ...

http://www.cruisecooler.com/Thermostats.html

this sight also also has high flow pumps for Jeeps .. ... unsure how they would compare to Flowkooler and Desco but claim "Cruise Cooler pumps flow more than any other brand per application".

These pumps are really rather simple. The design is dictated by the OEM pump, installed is the largest impeller that the OEM casting will accept. If the pump has a tight fitting back plate, an open back impeller is the best choice. If the back plate does not fit tight, a closed back impleller is used.

Some manufactures claim adding extra vanes (fins) might not be a better design as it may increase flow at lower rpms but would also effect flow rate at higher rpms ....

[BADASYJ]

I think that these high flow T-stats and housings are just gimmicks. The problem with overheating is in the radiator not the housing or T-stat. Unless of course the T-stat is bad.