MR. GADGET

Need to replace the thermostat in my 03

ANyone give me the inside on it?
Does not look like a gasket and from what I see not sealant on it. The thermostat has a thin rubber gasket is that it?

Got 122k on it and change the coolant around 90k give or take.
After reading about the plastic drain valve on the bottom I really dont want to use it was thinking about just pulling the thermo housing and letting it drain what ever then top it off. Or take the cap off an suck some out of there and then replace when done.

Just don't want a 15 min job turning into a 3-5 hr thing of replacing a hose or clamps, or valve and so on just to save a little coolant.

Also when gets warm/ hot from running, as normal, it pushs coolant to the overflow, is that enough to mak a difference that say when I get home I unplug it so when it cools it can not pull the coolant back saving some maybe?

No real problems other then the truck is running at 200 deg more now then it has in the past towing and at 70 + before I remember it more to the left at about 190

Also anyone replace their cap when they do the thermostat. Never had a problem with a cap....Don't know what to look for on that. All the hoses are good and hard all the time... What I remember that was always key..

1-2-3

Thermostat is a 10 minute job. Do this:

Drain coolant down below the thermostat level. No need to drain it all.

Use small vice grip pliers to hold the belt to the pulley before and after the WP.

Loosen belt and slip it off the WP only.

Remove the two 10mm bolts holding WP on.

Remove WP. Might have to work it a bit.

Clean surface where WP will go. Scraper and wire wheel works well.

Install new WP with gasket.

Place belt back where it goes.

Put coolant back in.

Check for leaks.

Enjoy.

MR. GADGET

But is there any sealant on the thermostat? Or is it just metal on metal using the rubber ring on the thermostat only?

No real plans to do the water pump now, no leaking or sound coming from it.

1-2-3

Well I guess I'm on crack today. Looking at some pics, I'm betting there's a gasket under the housing.

reisenbise

just the rubber around t-stat

dezeldog

X2 on just the rubber on the 'stat

Jim

MR. GADGET

Cool thanks, got the t stat from genos and it had the rubber ring around, going to do it after work one day later in the week.
Should be fast.

1-2-3

What they said

AH64ID

I don't know much about the Gates thermostats, but I would consider running a Genuine Cummins one.

What the guys have said for the procedure is right on, a very easy job.

klx650a2

Here is my unbiased 2 cents. Buy a genuine Cummins thermostat. More money, but there are no more temperature swings and "it just works".

Purplezr2

I bought a genuine Cummins at the dealer for like 35 bucks, the one at the parts store was 27 I believe.

jpajax

Are you putting a lower temp. in or staying with factory?

AH64ID

I guess Geno's does offer both. I would be curious what the crack and full open temps are on the Gates ones.

Stock is 190±3 for crack, and full open at 207*.