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Topic: Cummins parts # assistance cooling system (Read 1126 times) previous topic - next topic

Cummins parts # assistance cooling system

2001, 8.3 ISC

I am about to do an entire cooling system flush and componenets replacement. One is to replace the Thermostat. Using my engine number and Cummins quick serve, I have found every item but one. I cannot anywhere find the part number for a gasket on the Thermostat housing, Outlet pipe. I have a  new thermostat in hand, but it also did not come with any sort of sealing ring or gasket.

attached is what I see if I go to quick serve.....is it that IN/OUT have same gasket and cummins QS just does not show it on outlet side?....anyone done this is recent past that would know.....Thanks.



Re: Cummins parts # assistance cooling system

Reply #1 –
This won't help now but look on Ebay for a parts manual for the engine may come in handy.

Re: Cummins parts # assistance cooling system

Reply #2 –
I actually have an entire PDF service manual, that was supposedly for the ISC engine, and though most of it appears to be ISC specific, the cooling section shows the setup with the 2 thermostats, and much different gasket.

Re: Cummins parts # assistance cooling system

Reply #4 –
Mike when I went to cummins for my water pump gaskets (A few months back) they told me quick serve was having some problems.  If there is a cummins dealer near you it might help to take numbers and go by service center to get gasket numbers.  I found that the gaskets from cummins were very competitive with NAPA.  Now water pump was different story NAPA was about half with lifetime warranty.
Chris

Re: Cummins parts # assistance cooling system

Reply #5 –
Hey guys thanks for some feedback. I have tons of gasket paper and ability to make my own, but I was guessing these might be one of those heavier gaskets that is part fiber and part rubber. guessing like any other cooling system maybe only running 13-16 psi anyway. No Cummins places nearby that I know of, maybe some in one of the big cities. Chris, was there anything special about the gaskets that you got or we they just of the heavy fiber paper variety? Curious when you got your water pump from NAPA, what info did you have to provide just year and engine model?

Re: Cummins parts # assistance cooling system

Reply #6 –
Called Cummins of Birmingham. It appears that even they cannot find it based on databases sources etc. Luckily one of the techs remembers this coming up with with a customer about a year ago and he had ordered 2 of the gaskets after a discussion with Cummins direct. He still had one in his tool box and was able to provide the number 5398279. They are sending me one free of charge due to the inconvenience of quickserv being non supportive.

So,.... that others can find if need be. If you are working on an 8.3 ISC with the single thermostat (EC9015), 90 degree outlet pipe (W09034) the gasket for the application is 5398279....they tell me it is near identical to the inlet pipe gasket (5398273) but a bit different in diameter.

Re: Cummins parts # assistance cooling system

Reply #8 –
T Gordon,

Amazon link, 3945603 was superseded/replaced by 5398273. That is the gasket for the Intake pipe, not the Outlet pipe that has the thermostat connection. According to cummins, though it is close in design, the 5398279 is different and is the proper number for the Outlet/themostat application.

Re: Cummins parts # assistance cooling system

Reply #9 –


Have you found a 5398279?

Re: Cummins parts # assistance cooling system

Reply #10 –
Yes, I now have one in hand, Birmingham Cummins sent me one for free due to the inconvenience. If you go to any Cummins web site and put that number in it DOES come up called a "Connection gasket". It Looks very similar to the one on the amazon link, but cummins tells me it IS different in size.

**NOTE**...this gasket is not just a plain old paper oval that is very commonly seen an many thermostat housings. Its is a stamped steel overall surface with an imbedded rubber section.
Not to say RTV or heavy gasket paper might not work, but I have seen several such applications over the years that have failed as obvioulsy some setups there is greater pressure in that area than paper or rtv can handle. I have made hundreds of cooling gaskets in my day. But, in a vehicle that I am hoping will take us all over this country and be 100% realiable, I did not want to have something that might do the job, I wanted the proper item.

Just for heck of it I searched on  Amazon for the number I was provided by Cummins, as well as the one  you provided. It does come up, as does the OLD inlet gasket number 3945603. If you look in this picture they do look near identical, maybe a bit different but hard to tell in pictures. But according to the subject matter experts "Cummins" they are not identical. I clearly asked them would the 3945603 maybe work for both locations and that was just overlooked in the Cummins drawings, they stated they were close but not close enough....as both are the same price, they had nothing to gain by telling me "Here is the proper one, and we suggest you use the one designed for the location". I sort of wish I was also replacing the inlet side, but have no reason to do so. Otherwise I would measure the diff in detail.

Re: Cummins parts # assistance cooling system

Reply #11 –
UPDATE:
Finally got around to doing this work, and the answer to the sealing element is NEITHER Gasket.

The mating connection between the Block and the Thermostat housing/Upper radiator hose pipe is done by 2 orings. 1 on each side of the Thermostat. As I was replacing my thermostat due to its age, it came with the 2 orings. These Orings were not your standard perfectly round variety. Looking on Cummins site, I dont see where they are available without also buying the Tstat. That is if one wanted to remove the tstat for flushing. Flushing takes plenty long enough even with the tstat out. Removing the pipe, and making a temp gasket for a flush without the tstat is a simple process. But, If I break the seal would want to replace those Orings. Will check into sourcing those, when next a flush is needed.

Re: Cummins parts # assistance cooling system

Reply #12 –
When you disturb ANY "Packing preformed" it must be changed out when re-installing component. When initially installed, it conforms to the surface areas and is compressed to fill the voids in recessed flanges. Even minute surface imperfections is embossed into seal. So if you disturb packing, it will never re-form into new areas and result in leaks.

Re: Cummins parts # assistance cooling system

Reply #13 –
Quote from: master2301 –
When you disturb ANY "Packing preformed" it must be changed out when re-installing component. When initially installed, it conforms to the surface areas and is compressed to fill the voids in recessed flanges. Even minute surface imperfections is embossed into seal. So if you disturb packing, it will never re-form into new areas and result in leaks.

Fully agree.

Just not sure of any cummins part # to share on just the Orings. Or if there are even any at all, one may have to buy the entire tstat to get them, but surely not.