Correct thermostat for 440-3?

[bagodriver26]

Sent: 6/10/2004

what degree thermostat do I need for the 440?

[Sea Hag]

Sent: 6/10/2004

The thermostat for a 440 is 185 Degree . It also has to be the skirted type , for the 440 which has the lower portion ( engine side )of the thermostat enclosed with three ports for the water flow - this restricts the coolant flo to  keep it in the engine block a little longer to properly cool the engine evenly . with the non skirted type installed the 440 3 will run too hot as the coolant passes through the block and radiator too fast , not allowing the coolant to properly asorb engine heat . I,ve been told that this can cause  coolant to boil and force coolant away from portions of the block  and cause major engine damage . There is a OEM sticker on the air-horn of air-cleaner that shows a drawing and also in the Dodge chassis service manual . Mine is hard to read but has Dodge part number 3837 609 From what I can make out .This differs from the parts catalog  . if someone else can read theirs and these are incorrect please post the proper number .The 360 can use either type  and I believe the 318 and 413 can also .  Only the 440 3 needs the skirted one . Sea Hag

[winnedaygo619]

Sent: 7/9/2004

i found it  went to five different auto part stored 2 dodge dealers and dodge dealer had it skirted thermostat heres a pic  it was only 11 bucks

[denisondc]

Sent: 7/9/2004

And you can order them from www.summitracing.com. Their part number is MRG-4367 for the 180 degree unit, MRG-4366 for the 160 degree unit. Similar cost.

Stewart Components Inc also has the skirted type thermostats, and their web page says you can order from them directly.

https://www.stewartcomponents.com/index.php?route=product/product&path=61&product_id=63

[AlienImpulse]

Sent: 7/24/2004

Hag, I have a 1978 440-3, and the thermostat # (3837609) you posted is correct. Mine is easily readable. Currently mine has no thermostat. Wondering if I should put one in? I'd feel better having one installed but who knows what other problems it might bring up!

Jeff

[Sea Hag]

Sent: 7/24/2004

Alan - YES you need to install a thermostat or you will ruin your engine  - I left a reply to you other post prior to reading this one . the manual calls for a 185 degree . But since the only coolant control vacuum switch is for the EGR and it is a 85 degree switch ( for 76 anyway ), so going to one of the 180 degree thermostats above should work fine . I guess I should of gone to Chrysler before replacing mine but I hate paying the big $$$$$$ at a Chrysler dealer . Sea Hag

[AlienImpulse]

From: AlienImpulse
Sent: 7/24/2004

winnedaygo619...is there any chance you could post the part number? I cannot read it from the pic!

[winnedaygo619]

Sent: 7/25/2004

part # e-4  3418459  this is the 190 thermostat

[AlienImpulse]

Sent: 7/25/2004

OK the one from Summit is 10 bucks with another 10 bucks for a "handling" charge which means I get it some time in the next 14 days and it costs me 20 bucks for a thermostat, and the one from Stewart says that I 'must" have a Stewart water pump to use it, and it will end up being the same price & shipping time as the one from Summit. I'm leaving Friday for a short trip. Fact is I went from RI to Tennessee & back, sat in slow moving traffic for 5 hours in, and 5 hours back with no thermostat, so I would think installing a non skirted thermostat has gotta be better than none.
While I was at NAPA yesterday I gave them the 3837609 part number, and it cross referenced to a non skirted NAPA thermostat. I think I'm just gonna put in the NAPA thermostat in for now, and see if I can get the skirted one later.
I understand what a thermostat does, and have installed many over the years, but it was my own fault for taking it for granted that the idiot who owned the RV before me would have yanked out the old thermostat! In other words, had I known that there was no thermostat before I left for Tennessee I would have most definitely installed one before I left!
Between the problems with the Tranny (had to rebuild), 17.5" tire replacement (a grand to buy), trying to get my brakes working, trying to fix my gas gauge, get my refrigerator working, rebuilding the ceiling, and waterproofing the roof, and quiet down a rotted out (entire) exhaust, I never got a chance to pull the thermostat...or lack there of!!
Thanks again everyone,
Jeff

[Crazytrain]

Sent: 8/4/2004

Hi Girls and Guys ,

went hunting for a skirted thermostat, and the part guy told me that Chrysler don't list these anymore.

where can I find a skirted thermostat???

Crazy Train

[metrawatt]

Sent: 8/5/2004

I just bought mine from jegs.com its made by  a company called BeCool part number 134-78007, it looks just like the factory original in my RV right now.  I have yet to install it but as soon as I opened the box I knew I had bought the right one, not like the ones NAPA, Advance, Dodge dealer and Summit tried to sell me.

Some folks say the skirted stat is a restricted flow, this is NOT so.   Take a skirted stat and a "normal" one and boil them on your stove.  You will see the huge difference in flow.  The skirted stat has a much bigger opening and apparently fails to open!

[denisondc]

Sent: 8/5/2004

The skirted thermostats I got from Summit Racing looks just like the one is winnedaygo619s picture, message #4 earlier in this thread, though of course summit sells the regular passenger car thermostats also.

[Jupp318]

Sent: 8/8/2004

When I had my overheating problem with the electric fan, I checked with my service manual that I had the correct thermostat. I was surprised to find that the skirted thermostat is only correct in the 413 & 440 engines.  The 318 has a non-skirted version.

Cheers Ian...

[Sea Hag]

Sent: 8/10/2004
The 440 is the only one that needs the skirted thermostat. the parts manual says 413 318 & 360 can use either type . Sea Hag

[denisondc]

Sent: 8/11/2004
I believe that parts catalog has a mistak W%
The air cleaner inlet horn on my 413 has a label showing the skirted thermostat. I just uploaded a picture of the thermostat mount in my 413 water pump housing, showing why the skirted thermostat is needed. Its in my photo album, which is now on page 10 of the pictures, and on the 2nd page of my album - along with a picture of the thermostat label on the air cleaner. I had a regular thermostat in there for a while many years back, and my water temperature wandered up and down whenever it liked - though it didn't overheat, probably because the radiator had just been cleaned that spring. Afterward I made up a steel collar to fit down into the area below that collar, to close off the warm-up loop. That worked okay for years, but I replaced it last spring when I got a skirted thermostat. Now my water temp readings stay very steady - even when its hot outside and Im climbing hills or sitting in traffic. I have not seen a 440 water pump housing with the thermostat removed, so I don't know if it looks the same inside. My 32 Chevy sedan takes the same type of skirted thermostat, though smaller in diameter.

[Sea Hag]

Sent: 8/11/2004

Dave , I though I may have misspoke when I posted the 413 info . the parts catalog does not match my air cleaner horn sticker number on my 440 either . It as actually in my 76 service manual that stated the 360 could use either type . I recently replaced the thermostat in my 440 after flushing and rinsing the block ,swapping radiators for one from a donor chassis that wasn't clogged and installing the missing fan shroud .The thermostat that was in there from PO was the wrong one . I Installed a Slant 13478  180 degree non skirted type ' but has a much smaller center valve opening than others Ive seen makes me wounder if thats how they restrict the flow . it supposedly crossed over from the Chrysler number on my air cleaner sticker . On my recent trip the temp stayed around 190 or less even in traffic jambs . ambient air temp was mild for this time of year at around 80 degrees . at speeds over 65 MPH in hilly country the temp got to 200 or a touch over not near 210 which is the next mark on the gauge and would drop back under 200 if I kept it under 65MPH . the changes in temp were gradual  and stayed pretty steady . It would be interesting to see what the difference is if I can find a correct skirted one with the original part number .
      Metrawatt - the skirted thermostat does restrict the flow . not by the valve opening but by the skirt and the three or four small ports in the bottom of the skirt . I was told that it slows the flow to allow the coolant to adsorb more engine heat by a very knowledgeable and reputable mechanic friend of mine . he said with out one the block or heads can biol the coolant in spots and force coolant away from that area , it is a major problem with some of the Chrysler engines . Sea Hag

[denisondc]

Sent: 8/11/2004

If your radiator is pretty clean, then a normal thermostat will probably work fine for a couple of years at least. As the radiator loses its effectiveness though, I believe the original style thermostat will be nicer to have. With most of my old cars, having the thermostat out results in the water temp reading staying low -- assuming the radiator was good. In my little 3 cylinder 2 stroke saab however, leaving the thermostat out meant overheating on every hill - the temp needle would seesaw up and down like an altimeter! It must depend on the relative sizes and capabilities of the cooling system parts; water jacket, radiator, pump, things like that.

[Sea Hag]

Sent: 8/12/2004

Yes My radiator and block are very clean inside . before I removed the old radiator I  drained the system including the block . Flushed and rinsed it twice . then filled the system with water to test and rinse  after I had the donors radiator cleaned , tested and installed . I then drained it and filled the system with antifreeze and a Bottle of  anti rust/ lubricant additive . after all that work I intend to change the coolant every couple of years at least , to keep it that way . The old radiator had been previously damaged and repaired at one time . it also had a lot of junk deposits in it . Not alot of rust and no oil in old coolant but due for a change .
  In reply #19 I meant to say running the wrong Type thermostat ill cause damage to the engine not running with no thermostat .  Sea Hag

[lockman]

Sent: 8/28/2004

Had a beast of a time finding a skirted thermostat. First Chrysler dealer said part # 3837609 was no longer available and I should go to my local parts store. No luck there, tried every chain in town, and the cost to bring one in from on-line suppliers in the States was very expensive. Did some web research and found Chrysler # 3512998 is a direct replacement. Second dealer was more helpful, confirmed #3512998 was a skirted 185 degree thermostat and even found me a dealer across town that had one in stock. Caused a little flurry of interest at the counter as some of the new kids had never seen one before. It fit perfectly and dropped my high temps by about 10 degrees. Cost me approx. $14.00 US, cheap insurance in my books.

[Crazytrain]

Sent: 9/6/2004

Hi everybody.

I have to admit. I thought that the skirted type thermostat was an urban legend. My 440 had the tendency to run a little hot. I bought a Mr.Gasket 180 skirted thermostat and I replace the 160 standard type.

I did 400 miles this week end towing my car and the temp is stable!!!

I'M A BELIEVER!!! The skirted thermostat is mandatory on a 440-3.

Crazy Train

[oldRoadRanger_al]

Sent: 2/18/2005

Hi all,
What resource this site is, here’s some important info on this subject.
I bought a proper balanced/skirted thermostat like the original Chrysler from jegs.com (BeCool part number 134-78007) for 20 bucks +, I then ran across the info below on a skirted Robertshaw available at Autozone for $4.99. Oh well… at least you guys can now have the correct skirted design thermostat at a cheap price!

"Robertshaw Extra Performance # 370-180 which is the correct design and part number for the 440 motor at Autozone for $4.99
The Robertshaw Extra Performance series thermostats have a dual function.
Unlike the flat disc-type t-stat, this one has a skirt that moves up and down.
If the t-stat housing is made for this unit, it will have a seat down below the skirt.
When the engine is cold, the water flows from the block through a bypass hose or passage, maintaining good flow in the block.
When the engine gets to temp, the skirt drops, allowing less flow through the bypass and more through the radiator.
When the engine is pulling a good hill (temp above setpoint), the skirt blocks the bypass completely, and the bulk of the flow is directed to the radiator.
Advantages include better flow in the block, better warm-up, and better cooling flow through the radiator.
Using a flat-type t-stat in a housing that has a bypass port will not allow full flow to the radiator, limiting cooling capacity. In addition, the skirted design is balanced- water pressure from the pump does not effect opening and closing at all.
Design is used extensively in bigger diesel engines."

[denisondc]

Sent: 2/20/2005

     Thanks for the autozone part no.    I think RoberShaw actually produces the thermostats for half a dozen different brands sold by different retailers. 
    I have tried all 3 temperature thermostats available, the 160, the 180, and the 195.  They all work fine with my 413, just the temperature needle points to a different part of the center section on the gauge; left-of-center, centered, or right-of-center.   I have the 160 in now, since we were using it in summer time temps in the southern U.S. and towing a car.   It probably wasn't necessary, so I expect to switch back to the 180 the next time I have it opened up.  The 195 makes the heater work a little better in cold weather though.  Still doesn't get the interior warm if its below freezing outside.

[oldRoadRanger_al]

Sent: 2/23/2005

It looks like I flapped my beak a little too quick in the earlier post. I went down to Autozone and in this part of the country they no longer carry RobertShaw Extra Performance thermostats, still listed in the computer though.
Further Internet study has shown RobertShaw was sold and that the BeCool & Mr. Gasket 'stats are one and the same as... and made by RobertShaw (the BeCool I got even has #370-180 stamped in it).
The search continues for this skirted thermostat at a good price....

[intofire1]

Sent: 3/6/2005

Hi,
Has anyone had trouble with the part that houses the thermostat. Where would I get this part? Gil

[denisondc]

Sent: 3/6/2005

If you cant find one anywhere else, I expect to have one arriving via media mail in a week or two. Hopefully it wont be badly corroded. Would be glad to pass it on to you for what it cost me. -which isn't much-.
In the meantime you make send an email to Arizona RV and ask them if they have one. www.azrvinc.com.
I was kind of thinking of trying to get someone to cast up a few new ones in bronze.