I am thinking about replacing/upgrading the radiator with oversize high performance radiator & Transmission oil pan. Anyone has done this? I have a 94/U225 Cummins 12V B engine and MT643 Allison. Any trusted suppliers I should talk with? I want to see if i can run cooler.
Thank you,
AL
I am not familiar with the designation 12V B enigne but if you have a Cummins BT5.9 you may be overly concerned about the temperature. I had a 93, U225 with the 5.9 and once outside temps got over 90 degrees I was very concerned about my engine temps. I spent almost $2000 trying to cool the thing down before I found a Cummins Tech bulletin that stated the maximum operating temperature of the BT5.9 was 240 degrees. No, I can't find it again. I already looked on my computer and online but it may be in the archives on this forum.I am pretty sure I posted a copy of if on the Froum in 2009. I am not very good at searching for old threads.
As a point of interest, before I found this bulletin, I added a 24" X 24" X 3" aluminum radiator I bought off of eBay to the front of the coach. Banks Stinger on Cumins 230hp (http://www.foreforums.com/index.php?topic=10448.msg49019#msg49019) I mounted it behind the A/C condenser and plumed it through the 3/4" heater hose via T's creating a loop through the auxiliary radiator. It dropped the operating temperature about 10 degrees on those hot days in Oklahoma. I also installed a valve so I could shut off the cooling loop during the winter. This project was under $300.
Prior to the Aux radiator my coach would reach 210 to 225 going up even a small hill when outside temps were 100 degrees. It seldom got over 215 even on long large hills after the additional radiator.
I hope this helps you peace of mind and saves you a lot of wasted cash. That new High Efficiency radiator installed will probably cost you over $2000 alone.
According to the Cummins Service Manual, the normal thermostat temperature range is 180 to 199 degrees and the maximum operating temperature for the B9 is 215 degrees. Here's the applicable page. Elsewhere in the manual, the writer refers to 219 degree systems with a 15 psi radiator cap. Looks like 219 would be the maximum. I still have the manuals listed in the classifieds if you're interested.
jor
I have seen additional radiators in the engine compartment itself and front radiators with and without water squirters spraying onto them on u225's.
Never seen an overheated coolant loss u225 without the additional cooling either.
I have intentionally driven u300 6v's up baker grade out of Barstow in 110 weather at full power to show the owners that the gauge stopped at 240 with no damage or coolant loss many times.
No one likes seeing anything run past 180 degrees but unless someone can mention any coolant loss or other issues the fix you are contemplating may be visible on a gauge only versus a actual circumstance that will cause a problem.
My two cents.
Bob
Worth at least a nickel Bob, maybe a dime at times
I have a new radiator on my U300 now and I haven't experienced any overheating. I'm sure I'm keeping my coach for the rest of my life, so I've decided if I ever need additional cooling I'll install side radiators on either side of the engine. I'll get rid of the huge muffler and replace it with a straight pipe or perhaps a resonator if the straight pipe is too loud. Removing the muffler will allow plenty of room for a driver's side radiator. There's already plenty of room for a passenger side radiator. I'll keep the existing rear radiator of course. I'll size the new radiators so they've got as much capacity as the existing rear radiator and install valves to isolate all three radiators from the rest of the system. If I ever lose a radiator again I won't be stranded. I'll install electric water pumps for the new radiators and electric fans. I definitely will NOT install hydraulic fan motors and pump. I'll install an additional alternator that will be independent from the rest of the coach and will only power the new water pumps and fans. I'll make a heavy gauge cable to connect the new alternator to the coach electric system in an emergency and carry the cable with me in case I ever lose my main alternator again. It wouldn't be worth doing these modifications to a coach I didn't intend to keep forever. With a new radiator I may never need additional cooling because I seldom climb steep grades in hot climates... but if I ever do :)
...and I was considering building an air scoop that sticks out the side of the coach in front of the new side radiator with a big duct around to the back of the new radiator to force cool air through the radiator even if I lose the electric fan... but that would look kinda radical! haha ...okay so I better give this some more thought huh?
Jon, that 219 temp seems a lot more reasonable to me than 240 but I did see a Cummins document stating 240 was the maximum. Is your manual a Cummins document?
...or maybe the big intake scoop should be over the outside of the radiator with an electric puller fan on the inside of the radiator and an exhaust air duct that puts the hot air out the bottom of the coach ...that would be a lot simpler huh? ...hmmm ...(wittle bwain smoking)
Al,
How hot is it getting? Have always heard that the Cummins 6BT 5.9 will handle overheating quite well. But certainly would not want to push the overheating any length of time!
Hi, Kent. Yes, it's the Factory Service Manual which I purchased from Cummins. It has the Cummins copyright.
jor
Thank you all.
My main concern is Transmission oil temperature. It reaches 210/220 time to time, mostly it happens when it is pushed to run at 70mph. And not constantly what I mean is I usually keep my cruse on 62/63 mph and time to time get on up to 70 mpg and let it come back down to set cruse control speed. When run like this Trans oil temp goes up. Anyway first thing first; I am changing the oil to Transynd from "dextron 3 mercron" Let's see if Transynd oil run the same way or run cooler. We are doing some improvement in and around the engine so I am just checking things out to see what and why if I should do some "oversize" improvements ... I am one of those type, I rather take care of it now and build/add with extras if I can, but within reason.
Non issue at 210-220 everyone worries needlessly. Drive it.
Bob
Like Bob said, no problem. The max on your Allison is 250 degrees in the sump according to the Operating Manual.
jor
Thank you.
I had some overheat issues on my U225 which turned out to be a faulty thermostat. Ever since that was changed out things have been pretty decent.
Kent's auxiliary radiator idea behind the front A/C radiator seems to me to be a great - and pretty cheap - way to address any hot weather problems. And a simple ball-valve arrangement to turn it "on" and "off" would work pretty well, I think. As long as the aux radiator doesn't cause low coolant when on (or overflow when off).
I do flush my radiator with fresh water from inside the coach (using some "Simple Green"). The radiator looked purty when I was done but it still had heating issues 'til I got the thermostat replaced. (Which, by the way, is no fun!)
It's always good to hear that temperatures which raise the hackles on the back of a new owner's neck are common and not a serious problem.
Craig
Thank you Craig. Since I upgraded my Trans oil to TranSynd it no longer reaches 200 degree, not an issue anymore.
The other day on about 100 mil or so drive to friends lake house at about 98 degree day, I pushed it hard to see how it is going to behave and trans oil temp got to 200 degree but no more, mostly it was in 180-190 and on the way back i drove mostly at 55-65 mph and trans oil temp never got to 185. Love TranSynd.
Thanks for the report. That's really nice to know.
Did you change your transmission fluid yourself or have it done. I've always wondered where to dispose of the old fluid. Not as easy as getting rid of motor oil.
Craig
I am luck, I have a friend owns a shop. He is specialized in building Rock climbing Jeep's. So most of his work is around suspension, but he is a wizard around anything with wheels. We did it together at his shop (well I was there standing around with a paper towel in my hand) I believe he has a service that picks up used oil from him once a month or something. I have not done my own oil change for sometime now, but back in the day with my father we have rebuild few classic cars together, back then we use to take used oil to parts stores like auto zone and they had a collection container. Don't they do that anymore?
Nice to see lowered temps.
Is this the original radiator? If so, congrats. For one to last that long and survive says something for whomever built the core.
There are only so many cycles before radiators fail or in the least need to have their tanks re-soldered.
Have you ever checked the flow to insure there are no restrictions?
Also the return hose should have a coil spring inside to keep the (bottom) hose from closing up. The other issue may be with the fan/clutch assemble (if it has one). If everything else is working add some RMI25 to the system and keep the filters serviced (if it has them).
A way to tell if the fan assembly is working is to walk in front of the radiator and see if it tries to suck your pants off.
Our collective guess is the radiator is not the original. It looks almost new. Did not check flow. Don't know how, but I will ask my friend, he may know a thing or two about it. For now all looks and acts to be in good shape. Next we are going to install the new 4040XL resonator and get rid of the old engine compartment insulation. After that round i will be able to move inside and install two new LED TV's & upholstery. That should wrap it up for this year. Next year I will get its roof painted/sealed.
Along the way after we rid of the muffler and install the resonator i need to figure out a way to get 25-35 more HP. So far I believe it can be done safely by fuel plate and pump adjustments. For the HP work I found a reputable performance shop. We have one brilliant Diesel mechanic in the family but he is useless to us most of the time.