BMulvenna Posted July 26 Share Posted July 26 2004 Dynasty cummins 400 ISL. We have a pretty large leak in the radiator. Don't know yet if it is the radiator core or the tank. Trying to get ahead of it, so if we need a radiator does anyone have a part number and possibly a source for the radiator and tank? Called Monaco parts and they want $14,000 for radiator, CAC, tanks etc. Hesitate to use Bars leak or equivalent. Thoughts? I have pressurized the system and have a general location of the leak but have not pinpointed yet as it is behind the shroud. It could possibly be the tank that is leaking. Waiting for the ground to dry out in the rv park to investigate further. Any thoughts are appreciated. Thanks Mike Link to comment Share on other sites More sharing options...
Doug and Nicki Posted July 26 Share Posted July 26 Have your existing radiator repaired. It will cost a lot less. Link to comment Share on other sites More sharing options...
Tom Cherry Posted July 26 Share Posted July 26 https://sourcerv.com/radiators I'd at least talk to Jim or Scott at Source Engineering. They are Ex Monaco management and are experts and trusted for many things. 1 1 Link to comment Share on other sites More sharing options...
Ivan K Posted July 26 Share Posted July 26 If you end up having to use a sealer, there are so many and one of them seems preferred on this board but there is supposedly only one approved by Cummins, Zerex Super Sealer. Link to comment Share on other sites More sharing options...
PeterSchweizer Posted July 26 Share Posted July 26 We removed the radiator had our core replaced by a national big rig radiator and CAC supplier in 2020. Excellent job. Same warranty ,1yr, as a new one. Active Radiator supply Company on their site is a guid of what measurements they need to verify what you have. You have to dig on their site for our older monaco pages n diagrams of their sizes. If you have room I would add another row of core to increase cooling capacity ours was a rear Rad, so adding one or 2 to the back is possable just would have to make a bracket to stand off the small trans coole Link to comment Share on other sites More sharing options...
Tom Whitlow Posted July 27 Share Posted July 27 Years ago we took our Holiday Rambler's leaking generator radiator to a local radiator shop. They replaced the core. It lasted till we sold it, many years later. 2 Link to comment Share on other sites More sharing options...
jacwjames Posted July 27 Share Posted July 27 I had a new radiator installed in 2015, it looked good, it was from CG&J. We only took one long trip with it and then the rig was pretty much parked while I built a house doing most of the work myself so it took a loooooong time. Covid and other stuff. Finally took a trip in 2021 and the radiator started to seep on one side. I used a couple bottles of Irontite. It stopped the leak and since then put on another 15K miles. Link to comment Share on other sites More sharing options...
joefromperry Posted July 27 Share Posted July 27 +1 on C, G, & J. Exact match for my 2003 Signature. Link to comment Share on other sites More sharing options...
jacwjames Posted July 27 Share Posted July 27 1 hour ago, joefromperry said: +1 on C, G, & J. Exact match for my 2003 Signature. Yes I did use CG&J but I would not recommend. @Dr4Film also had a leak on his after a short while. My leak developed ~6 years after it was installed but during that time we did not use the coach that much. In 2021 after a long trip I found the seep. Yes the Irontite fixed it but have to wonder about future problems. I keep a very close eye on it. I also had a transmission heating problem. After the install we took a trip out west and did notice higher temps but attributed to me climbing a long grade in too low of gear. Then in 2021 I noticed the same thing, I had alarm set up on my Silverleaf and it would alert me of high temps, usually when stuck in traffic. The I saw the temps go up while I was backing into my garage, temps sometimes +235F. I contacted CG&J and questioned them on the sizing of the internal cooler and they could not tell me the size and/or how they determined the sizing (you would assume the dissected an old OEM radiator) their advise was to add an auxiliary cooler, which they would graciously sell me for ~$800. NOPE, not the right kind of customer support for me. I ultimately installed a Derale cooler which worked but then it developed a leak, they did send me a new core but decided to instead install a cooler like they install on rear radiator coaches, bought a used one from Visione RV and completely bypassed the internal cooler. If my radiator gives me anymore trouble I will not install another CG&J Link to comment Share on other sites More sharing options...
SteveD Posted July 27 Share Posted July 27 I had the same issue; 20 plus year old OEM radiator started leaking, pulled the unit and it had a Radiator Specialty part number on it. Radiator Specialty used to be the supplier for Monaco back in the day. local shop in Lodi CA was able to cross reference the number and located a new unit. With Freight it was the better part of $5k. But I have a side mount and it is huge. Do yourself a favor and don’t repair an old aluminum core unit. You’ll be chasing leaks forever. It’s time to replace it and get another 20 plus years out of it. 1 Link to comment Share on other sites More sharing options...
PeterSchweizer Posted July 28 Share Posted July 28 $ 5000 just for the part? I would shop around 1 Link to comment Share on other sites More sharing options...
joefromperry Posted July 28 Share Posted July 28 23 hours ago, jacwjames said: Yes I did use CG&J but I would not recommend. @Dr4Film also had a leak on his after a short while. My leak developed ~6 years after it was installed but during that time we did not use the coach that much. In 2021 after a long trip I found the seep. Yes the Irontite fixed it but have to wonder about future problems. I keep a very close eye on it. I also had a transmission heating problem. After the install we took a trip out west and did notice higher temps but attributed to me climbing a long grade in too low of gear. Then in 2021 I noticed the same thing, I had alarm set up on my Silverleaf and it would alert me of high temps, usually when stuck in traffic. The I saw the temps go up while I was backing into my garage, temps sometimes +235F. I contacted CG&J and questioned them on the sizing of the internal cooler and they could not tell me the size and/or how they determined the sizing (you would assume the dissected an old OEM radiator) their advise was to add an auxiliary cooler, which they would graciously sell me for ~$800. NOPE, not the right kind of customer support for me. I ultimately installed a Derale cooler which worked but then it developed a leak, they did send me a new core but decided to instead install a cooler like they install on rear radiator coaches, bought a used one from Visione RV and completely bypassed the internal cooler. If my radiator gives me anymore trouble I will not install another CG&J I had one of C, G, & J's radiators lead after just a couple years and only 25k miles. I shopped around other suppliers, but. the cost to replace was at least twice as much. I guess I got what I paid for. I did replace through them again, with a slight price break. What I discovered, after a suggestion from them, was it's quite possible, even probable, that my leak was because of electrolysis through the coolant weakening the radiator. When installing the new one, I added two ground straps between the radiator and the frame. Time will tell. I will say my transmission temps have decreased by a significant amount, which I am thankful for. New problem, though, is the sauer-danfoss electric fan control has failed, leaving my fans on full all the time. A wax valve kit from Source is my next investment. Always something with these older coaches. 1 Link to comment Share on other sites More sharing options...
BMulvenna Posted July 28 Author Share Posted July 28 On 7/26/2024 at 12:39 PM, Ivan K said: If you end up having to use a sealer, there are so many and one of them seems preferred on this board but there is supposedly only one approved by Cummins, Zerex Super Sealer. I am going to try the Zerex Super Sealer. Purchased Napa. Thanks for the suggestion. Wil advise this week with the results. Link to comment Share on other sites More sharing options...
Dr4Film Posted July 28 Share Posted July 28 25 minutes ago, bmulvenna@hotmail.com said: I am going to try the Zerex Super Sealer. Purchased Napa. Thanks for the suggestion. Wil advise this week with the results. If that doesn't work for you, I would try the Irontite. I had excellent results with the Irontite on my 2002 Windsor. Drove it for over another 5000 miles before having the radiator replaced. Then used it again to stop the coolant from seeping at the top somewhere a few years after the new one was installed. It also works on the Aqua-Hot Coolant Boiler Tank. https://tinyurl.com/4reje9h5 Link to comment Share on other sites More sharing options...
BMulvenna Posted July 28 Author Share Posted July 28 25 minutes ago, Dr4Film said: If that doesn't work for you, I would try the Irontite. I had excellent results with the Irontite on my 2002 Windsor. Drove it for over another 5000 miles before having the radiator replaced. Then used it again to stop the coolant from seeping at the top somewhere a few years after the new one was installed. It also works on the Aqua-Hot Coolant Boiler Tank. https://tinyurl.com/4reje9h5 Thanks, will keep that in mind. Link to comment Share on other sites More sharing options...
96 EVO Posted July 28 Share Posted July 28 On 7/27/2024 at 7:49 AM, SteveD said: I had the same issue; 20 plus year old OEM radiator started leaking, pulled the unit and it had a Radiator Specialty part number on it. Radiator Specialty used to be the supplier for Monaco back in the day. local shop in Lodi CA was able to cross reference the number and located a new unit. With Freight it was the better part of $5k. But I have a side mount and it is huge. So, your saying you were "Stuck in Lodi again!" 😆 1 2 Link to comment Share on other sites More sharing options...
SteveD Posted July 29 Share Posted July 29 16 hours ago, 96 EVO said: So, your saying you were "Stuck in Lodi again!" 😆 I like it… not anymore! 1 Link to comment Share on other sites More sharing options...
Solution BMulvenna Posted July 29 Author Solution Share Posted July 29 (edited) Zerex Super Sealer has stopped the leak. We will see what happens next week after driving around 150 miles. Thanks to Ivan K for the recommendation. Spoke with Jim at Source Engineering. He uis going to quote a new radiator if I end up needing one. He also said to dump 2 tablespoons of black pepper and drive it to plug the leak. Edited July 29 by bmulvenna@hotmail.com 2 Link to comment Share on other sites More sharing options...
joefromperry Posted July 29 Share Posted July 29 On 7/27/2024 at 9:46 AM, jacwjames said: decided to instead install a cooler like they install on rear radiator coaches, bought a used one from Visione RV and completely bypassed the internal cooler. I'm considering doing the same. Can you send me a picture of the trans cooler you added, in front of your radiator, I assume. Thanks. Joe Link to comment Share on other sites More sharing options...
jacwjames Posted July 29 Share Posted July 29 I didn't install it in front of the radiator, I installed it on the drivers side at the back next to engine right below the rear start switch. My primary fuel filter was mounted there but I abaonded it after I installed a FASS fuel system. I was able to mount it some structure that was there. This is the model I used, bought a used one for $300 from Visione RV Salvage in KY https://rvchassisparts.visonerv.com/cgi-bin/md/M120007/s1.pl? If you want new ~$$$$ here is a source https://radiatorsupplyhouse.com/products/monaco-transmission-engine-cooler-rsh-4635-oc-rs-4821-rev-a-s01803904-724635 First picture is without a cooling fan Second picture is with a cooling fan, which came off a Derale cooler that failed. Third picture is just a closeup, I just used a thermal snap type switch to turn it on, just used aluminum foil tape to fasten it to the inlet fitting. Bottom fitting is return. I Igot power from my passenger side electrical bay. I have a small fuse panel there that I power a couple things from. I have data logging set up on my Silverleaf. My wife returned from a trip and I checked the temps, the tranny ran between 166-175 after it got to temp, I saw no increases when she was pulling long grades heading north on I75. This is a significant change from when I returned without a cooler in Colorado where I saw temps to ~225F on grads and had some +230 when got stuck in traffic. Link to comment Share on other sites More sharing options...
joefromperry Posted July 30 Share Posted July 30 Thank you for the info and pics, Jim. I was thinking of abandoning the trans cooler inside the radiator and mounting a cooler below or above the hydraulic cooler that's in front of the radiator. I don't have room to put it in back like you did. And if I put it over the radiator, the fans will do the cooling and I won't have to add another fan. Thanks. Link to comment Share on other sites More sharing options...
amphi_sc Posted August 3 Share Posted August 3 Yesterday, as we were leaving a light house in the middle of nowhere 100+ miles from a major city we came across a tour bus whose passengers had exited and were enjoying the beauty totally unaware while the driver was trying to figure out his options. Their 1/2 hour stop might be a tad longer. It might take more than a couple of bottles of stop leak. Ouch! On a positive note, the rock was undamaged. P.s. Moderators feel free to delete this post. 1 Link to comment Share on other sites More sharing options...
Dr4Film Posted August 3 Share Posted August 3 Big Bummer! Will take a few hours to get a replacement tour coach out to them and to find a tow company to tow the disabled coach to a shop. 1 Link to comment Share on other sites More sharing options...
Benjamin Posted August 3 Share Posted August 3 The line there looks like the edge of the pavement. Did you see a puddle anywhere? That might be driveable with some duct tape, bungy cords or ratchet straps. Link to comment Share on other sites More sharing options...
amphi_sc Posted August 3 Share Posted August 3 (edited) Strong smell of antifreeze and it had all leaked out. Bottom and rear corner of radiator destroyed. He pulled down 150 feet from where the impact was. It ain't going anywhere under it's own power. Edited August 3 by amphi_sc 1 Link to comment Share on other sites More sharing options...
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