[Big Red]

Called Cummins today with my engine serial number and they told me it takes a 180* t-stat stopped at dodge and they say 190 and oreillys says 192?? Should I pony up and get an OEM...I always thought it was better to pay the 30 bucks for the oem vs the 5 bucks for the napa or aftermarket.

Secondly with 250k on my rig should I put in a new water pump? How hard? Is it a pressed on pulley or a bolted on one? (oreillys asked). Anything else I should do when I am re-doing the cooling system?? Thanx..

 

[nickg]

I run a 195F thermostat, Most efficent diesel combustion takes place at a higher operating temp. As for the waterpump, remove the belt and give the pulley a spin by hand and push/pull on it to check to see that the bearing is tight, if it is I'd leave it alone, also look for any coolant weeping from the tell tale hole, if there are any stains of coolant present replace the pump, mine has 430,000kms on the orginal.

If your experiencing cooling issues, check the rad its likely plugged with dirt/oil from the puke bottle or too short a vent hose allowing the oil to collect on the rad, best advice would be to remove the rad and clean it at a carwash, Mine took 10$ and a can of degreaser before water would pass thru it, yet when it was in the truck it looked clean (from the fan side of the rad)

 

[Big Red]

where did u get the 195?

 

[01dodge91ford]

I run a 195F thermostat, Most efficent diesel combustion takes place at a higher operating temp. As for the waterpump, remove the belt and give the pulley a spin by hand and push/pull on it to check to see that the bearing is tight, if it is I'd leave it alone, also look for any coolant weeping from the tell tale hole, if there are any stains of coolant present replace the pump, mine has 430,000kms on the orginal.

If your experiencing cooling issues, check the rad its likely plugged with dirt/oil from the puke bottle or too short a vent hose allowing the oil to collect on the rad, best advice would be to remove the rad and clean it at a carwash, Mine took 10$ and a can of degreaser before water would pass thru it, yet when it was in the truck it looked clean (from the fan side of the rad)

:ditto::ditto::ditto:

The puke bottle had mine totally clogged even with only 80k

 

[totalloser]

I tried the 180 thermostat and it boned my fuel efficiency BADLY. I lost 4 mpg (down to 14) with it in. Went back to the 190 with my below mods and my efficiency came back up to 18 again. The 180 stat lost me all the gains I got from sticks and exhaust. Even if it came with one, I wouldn't put one in.

Personally I recommend the factory 190 stat because it usually fails open. It will make the temp gauge fluctuate on some rigs (on some rigs the computer hides this fluctuation from the gauge) and when it's open it FLOWS compared to the aftermarket stats. Much bigger than the ones I have seen. The factory one will let the temp climb to about 200 or 210 then it will snap open and drop back down to 190. Most (all?) aftermarket ones progressively open a smaller orifice so they don't fluctuate.

 

[Shainer]

Needs to be a 190. There is nothing wrong with the Napa t-stat. A colder t-stat makes the computer think the engine is not warm yet, so it runs a different fuel map which kills your fuel mileage. If the pump isn't leaking I wouldn't touch it.

 

[kevstar1212]

does anybody have a problem with there truck taking forever to warm up in winter? on a winter nite (25*F) my truck could sit and run for a hour and not hardly budge the gauge.... thought it might be my Thermostat stuck open or something... not sure but it sure sucks not having a warm truck for the first couple miles down the road,,,

 

[jwalth02]

You have a 24 valve? Well they take forever to warm up because of all those valves. If you unlock the high idle (either at dealer or a smarty) your warm up time will be halved or more. They run too cool at idle and have caused problems over time. But if you run them down the road in a lower gear higher rpm's will warm it up really quick. Also plug in the block heater that'll help you warm up too.

 

[Big Red]

just got off the phone with cummins and dodge and both said if you want to go with 190 you have to go aftermarket-does this sound right...napa has stant, i always thought stant was junk???

 

[kevstar1212]

thanks thats kinda what i figured, i had the high idle unlocked with a smarty but it never seemed to want to kick in often... i live up here in ohio its plenty cold and over winter i think it may have kicked in like 3 or 4 times... , also i don't think my block heater works... how warm should it keep it? i plugged it in with the truck already hot and wen't to drive it after work and the gauge wasn't off the peg, and seemed to take just as long to warm up... i never had a problem starting though... couple cold nights at my girlfriends with the truck outside all night at -11 started right up the next day....

 

[longo244]

I bought my truck used with 124k on it. The temp gauge never reaches 190 unless you're running it hard with the A/C on and it's over 80 degrees out. In the winter it sits considerably below 190...probably half way btw 190 and the second slash on the temp gauge. Does anyone have any idea what temp thermostat would be in the truck? I have no problem pulling off 20 mpg on the hiway if i run the truck at 2k RPM's. You guys seem to think a warmer thermostat helps efficiency...I wonder if it'd be a good idea to change mine out. What do ya think?

 

[Shainer]

I bought my truck used with 124k on it. The temp gauge never reaches 190 unless you're running it hard with the A/C on and it's over 80 degrees out. In the winter it sits considerably below 190...probably half way btw 190 and the second slash on the temp gauge. Does anyone have any idea what temp thermostat would be in the truck? I have no problem pulling off 20 mpg on the hiway if i run the truck at 2k RPM's. You guys seem to think a warmer thermostat helps efficiency...I wonder if it'd be a good idea to change mine out. What do ya think?

You need to verify your gauge is accurate. I bet your sending unit is faulty

 

[Shainer]

just got off the phone with cummins and dodge and both said if you want to go with 190 you have to go aftermarket-does this sound right...napa has stant, i always thought stant was junk???

Do what you want. Not sure why they are telling you 180, but every Cummins I've worked on has a 190 in it. I even looked over some other posts and I see 190's... On Napa's web site is says 190 is the OEM temp. 180 is an alternate temp, so everything I'm finding says 190...Buy it from where ever you want too. Splitting hairs over a thermostat is crazy. Plenty of guys have the Napa t-stat with no issues.

 

[Big Red]

napa 190 is in! thanx guys-found out their is a tsb from dodge on this, to change some early (mine) cummins from the 180 to the 190...took me 6 mins to change, piece of cake.

 

[longo244]

You need to verify your gauge is accurate. I bet your sending unit is faulty

Does a 190* thermostat generally keep the truck consistently running at 190* on the temp gauge...yes I know this might sound like a stupid question but my car is not like that. If the thermostat is open the car reads 190*. My thermostat would stick open above 160 degrees and I had a CEL for like 6 months. It read coolant system failure. I replaced the coolant temp sensor and the car never overheated. My Scanguage was reading btw 160* and 170* (I didn't know the car was supposed to run btw 190 and 200*) then when winter came I had no heat...then I was like duh...thermostat is fubar but in the car, the temp gauge is more of an idiot light than an actual gauge...does anyone know how accurate the guage is? Let's say someone with a Scanguage or an aftermarket coolant temp gauge?

 

[nickg]

where did u get the 195?

typo error on my part! should read 190F, Stant makes a good thermo, now if you want to talk junky thermo's DONT ever instal a Motorad product, most auto supply houses carry them (here in Canada, Canadian Tire/Parts source carry Motorad products)

 

[ButterDiesel]

I have an Isspro water temp gauge in mine and it reads 190 when the truck is up to operating temp. I read somewhere that the stock stat is rated to 188 so you might as well say 190. Unless your car is a diesel, your comparing apples to oranges. Diesels are more efficient around 190-200 degrees. Even running around 210 won't hurt anything.

 

[longo244]

I have an Isspro water temp gauge in mine and it reads 190 when the truck is up to operating temp. I read somewhere that the stock stat is rated to 188 so you might as well say 190. Unless your car is a diesel, your comparing apples to oranges. Diesels are more efficient around 190-200 degrees. Even running around 210 won't hurt anything.

Car's not a diesel. I was just talking about the nature of temperature gauges in general. I was never sure how accurate they were....like I said...it turns out the one on my car is more of an idiot light than anything else.

 

[mark293]

My factory stat hunted around too much. I installed the napa 190 and she stays rock solid in the middle.