I Need to replace a leaking freeze plug, covered by the water pump and timing gear cover.

[tomgagne55]

I Need to replace a leaking freeze plug, covered by the water pump and timing gear cover.

I have a 2002 (2001 built) diplomat.  ISC 8.3, It has a stacked radiator and cac.  In order to get direct access to the freeze plug I need to remove the engine water pump as well as the cac.   Since they are stacked, can only the cac be removed ?  Is it a one man job ?  How much does the cac weigh and does anyone have any pictures?   Looking at it there are a few bolts and I’ve read in another forum that the hose connections can be removed from the rear?    

I have bits and pieces of what it’ll take, but does anyone have any additional info, or a good source?   Removing only the cac will significantly decrease the level of effort on this activity.

thanks 

Edited November 27, 2021 by tomgagne55
Picture of the freeze plug

[Ivylog]

I’ll “almost” guarantee “Dike Stop Leak” will fix it…BEST stop leak I’ve ever used. Had similar issue on a Cat 3406… lots of things in the way. That was 20 years ago and it still doesn’t leak. Recently my brother had a leak on a one year old turbo with the stupid hot water controlled VGT…stopped it too.

https://www.amazon.com/Dike-Radiator-Stop-Leak-Pint/dp/B07PWHJQZL/ref=mp_s_a_1_5?crid=BWYLIVLFL3N5&keywords=dike+stop+leak&qid=1638021792&qsid=146-4576598-2844959&sprefix=dike+%2Caps%2C271&sr=8-5&sres=B002HIB3GI%2CB00TO60CMW%2CB07PWHJQZL%2CB001QT9KO6%2CB0869GRFC7%2CB000OAEN7C%2CB00754T6TK%2CB076ZP45Z5%2CB000BRQ0TW%2CB002PX91OG%2CB0086H95X2%2CB000931OEO%2CB00D46NSTM%2CB00QYZIVA6

[wamcneil]

When my water pump was failing, it looked like the seal between the pump and the engine was leaking. Which really confused me.
Turns out there’s a drainage channel cast into the pump housing that catches a leak from the shaft seal and shunts it down to the bottom of the pump. I didn’t figure it out till after I pulled the pump and felt the loose bearings.

Is there any chance that what you’re seeing is actually coming from the pump?  

Cheers

Walter

[Rikadoo]

When i replaced my leaking radiator i also replaced my Water pump, t-stat, an hoses i left my cac in place. The radiator takes Two men to wrestel it out then back in. I will tell ya if your going thru all that work, ya might concider replacing the radiator at the same time. Im with Walter in that the original WP has a weep hole that when its seal goes bad it starts externally leaking coolant. The new wp has been updated many times an now they no longer have that. Let me know if you need more info.

 

 

[tomgagne55]

Thanks for the response, the water pump was replaced 2 months ago.  At the time the leak appeared to be fixed however it wasn’t.  I returned from a trip and waited for the mechanic to reinspect, and I also found this link describing similar circumstances. https://www.irv2.com/forums/f123/isc-coolant-leak-fyi-266160.html  In looking closer the freeze plug appears to be the issue.  The mechanic has refused the additional work because of the amount of time he is estimating (40hrs) it’ll take him.  I found another mechanic who is willing to “look” at it and as a fall back I’m trying to get enough information so if needed I’ll do it myself.    The fix for the issue I found on irv2 involves milling the timing gear cover, which the 1st mechanic didn’t want to do.  According to the mechanic  In order to replace the freeze plug ($6 part) remove the timing gear cover, the cac, radiator , the cam shaft and valve cover removed etc….   So in my continuous searching, I found that removing only the cac will give enough access.  My plan is to go the milling route as the material being removed is directly in front of the hole and is not serving any function.    I need to remove at most 1/4 inch and the timing cover bracket is over an inch thick, so any milling will not break any seal of the timing gear cover.  Sorry for the long explanation, if the CAC can be removed by itself, it’ll save some time.   

11 minutes ago, Rikadoo said:

When i replaced my leaking radiator i also replaced my Water pump, t-stat, an hoses i left my cac in place. The radiator takes Two men to wrestel it out then back in. I will tell ya if your going thru all that work, ya might concider replacing the radiator at the same time. Im with Walter in that the original WP has a weep hole that when its seal goes bad it starts externally leaking coolant. The new wp has been updated many times an now they no longer have that. Let me know if you need more info.

 

 

Thanks for the pictures it would appear that removing the radiator is the cleaner way to go. 

[tomgagne55]

2 hours ago, Ivylog said:

I’ll “almost” guarantee “Dike Stop Leak” will fix it…BEST stop leak I’ve ever used. Had similar issue on a Cat 3406… lots of things in the way. That was 20 years ago and it still doesn’t leak. Recently my brother had a leak on a one year old turbo with the stupid hot water controlled VGT…stopped it too.

https://www.amazon.com/Dike-Radiator-Stop-Leak-Pint/dp/B07PWHJQZL/ref=mp_s_a_1_5?crid=BWYLIVLFL3N5&keywords=dike+stop+leak&qid=1638021792&qsid=146-4576598-2844959&sprefix=dike+%2Caps%2C271&sr=8-5&sres=B002HIB3GI%2CB00TO60CMW%2CB07PWHJQZL%2CB001QT9KO6%2CB0869GRFC7%2CB000OAEN7C%2CB00754T6TK%2CB076ZP45Z5%2CB000BRQ0TW%2CB002PX91OG%2CB0086H95X2%2CB000931OEO%2CB00D46NSTM%2CB00QYZIVA6

I am reluctant to do this because it doesn’t seem to be a complete fix. I’m not on the road yet but wouldn’t feel confident.  Additionally if the freeze plug is rotted it’s only a matter of time before the hole gets bigger. Thanks for the suggestion! 

[Rikadoo]

Funny thing about freeze plugs, if ones bad…. The others are right behind it. My only experiance was from Chevy an fords an many years of working on cars for a living.

[tomgagne55]

This is how my setup is.   Are the bolts on the sides actually a bracket to hold the radiator in place?   So remove all the bolts, the input and output lines/hoses coolant/transmission lines, lower body panel and the radiator will slide out ?

19 minutes ago, Rikadoo said:

Funny thing about freeze plugs, if ones bad…. The others are right behind it. My only experiance was from Chevy an fords an many years of working on cars for a living.

This plug is in a spot where crud builds up and just sits so hopefully this is the only one.   I’ve looked at a few others and it appears to be surface rust. 

[Rikadoo]

So it appears your rig has the updated radiator already. I was told by the radiator Mfg. In Sac ca. That they were  the original mfg.s of the all Monacos an HR mh’s which at the time all Alluminum, which is what mine had. The radiator you are showing is like my replacement, same company, its just they no longer make the aluminum model. In fact when i went to the plant where there made the person told me while many of the coaches were still covered under warranty that when the alluminum radiator sprung a leak that they were upgraded to the version you currently have, which is what i now have. Looking at my new radiator you can see the “end tanks” which are bolted to the core… dont unbolt there, instead look at the aluminum one, on the very top you can see there are mounting ears on the edge of the tank, that is what holds them in place, i believe there are 3 on each tank. Also that center section of “bumper area” has to be removed to get it out, as mine would not lift up an out.

[tomgagne55]

I removed all the trim pieces and miscellaneous items in the way.  I don’t see a way to remove only the radiator.   Both the radiator and cac are mounted within a U channel bracket and the U bracket assembly is resting on the trailer hitch and the sides are one piece. The tanks of both cac and radiator are within the U channel.  It appears the entire assembly needs to be dropped then twisted/angled to remove as the assembly is wider than the back access.    Thanks for all the help.  Great forum!

[Rikadoo]

Tom sorry to see that, im reminded of peoples statements about our motorhomes, there like snowflakes cause no two are alike. Those two are going to be heavy, and bulky, be carefull an watch out for the pinch points.

[tomgagne55]

Thanks there is no way I can pull this one off, without a way to maneuver the assembly.   This looks more like what I have.