Radiator - Top mounting vibration dampers

[Birddog Pilot]

Does anyone have the part numbers and supply source for the two top radiator mounting vibration dampers? I have have the two lower mounts taken care of with rubber bushings, but need the information, part numbers, source, pictures, or whatever for the two uppers.

[Terry W]

Dick,

I bought them through

Mission Sales in Texas
888-481-0008

Part #55/1194-45 FS CR MOUNT NR 45 Qty 4

about $85 shipped to CA

They were very nice to deal with

Terry

[Birddog Pilot]

Thanks Terry. We are talking about the top two "hanging type" vibration isolation dampers aren't we? The reason I asked was because I found Paul Sullivan's post feom 2008 that lists Mission Supply and that part number, but reading Paul's post and others on the subject it appeared that P/N was being used for vibration isolation when attached to the threaded rods on the lower angled attach brackets. But if these are what you used on the upper attach points, apparently these are what I will be ordering. Thanks again.

[Terry W]

Sorry for the slow reply,

I believe we're on the same page. I ordered them when I had my radiator changed. Two for the top two for the bottom. Sorry to say that's really all I know about them.

[Birddog Pilot]

Fantastic information Terry, thanks again. Looking at Mission's web sitethese vibration isolators look to be really first class. Even better is that the same item can be usedon both the top and bottom mounting positions.
I am curious as to whether you recall where your radiator was leaking andwas it one of WRV's (non-repairable) aluminum radiators? The reason I am asking, and I probably shouldmake this a separate topic for this "Forum," is to see how common thisfailure has become. I am now on mythird radiator failure and each one has been on the aft portion of the unit, onthe bottom section of the vertical area of the weld/braze joint where the aftoil tank is fastened to the coolant radiator. I personally have seen two Alpines that hadthe same failure point and I believe I recall reading here on the"Forum" of others that have had the same failure location.
My first WRV/OEM aluminum radiator went 13,000 miles before beingreplaced with a brass and steel unit manufactured by Mac's Radiators inPortland, OR. That unit went two yearsand an additional 13,000 miles (is there a pattern here?) before it too beganto leak at the same location. This timethe radiator was overhauled and reinstalled by Cummins Cal Pacific in El Cajon,CA. We are currently headed north toPortland and Mac's facility with yet another leaking radiator, yep same failurepoint. The latest failure occurred afteranother five years and 20,000 additional miles. So at about 46,000 miles and ten years inservice this particular Alpine Coach has definitely demonstrated that it eats radiators atan alarming rate. Hopefully Mac's will have somegood ideas for repairs or replacement; then along with your recommendation for the new vibration isolatorsthe problem might actually be resolved.

[DrDaveMA]

Dick, it sounds like you are the original purchaser of the coach. Having gone through 3 radiators in 46 k miles I wonder if the vibration dampeners were changed each time? I would also look for other issues causing the failure. When I took delivery of our new '05 during the PDI I noticed the 2 brackets that mount the transmission cooler that were broken (the brackets can easily be seen from outside with the shroud in place). The dealer welded them and they were fine for a year or two then broke again. That time I went to my local hardware store and bought the heaviest shelf brackets I could find, (about 6" long). I bolted them in place and no problems since, and that includes a trip to Alaska and 65 k miles on the odometer. I know this is the old "shade tree mechanic" method, but it has held ever since.

What I am suggesting is that you carefully inspect the entire area for something else being the root cause of your problems. I know there have been radiator issues, but in your case three is excessive unless Mac's and Cummins El Cajon did not fix the problem, they just cured the symptom. I imagine with the discussions here about radiator problems it would be easy to just do a swap and call it fixed while not digging into the root cause, however to me it seems the root cause has not been found. Hopefully when you remove the radiator and inspect the vibration dampeners you will see that they are damaged and that they are the originals installed by WRV. If they have been replaced, as I hope both Mac's and Cummins would have done, you need to dig deeper, maybe the method of damage to the dampeners will give you a hint where to look. It could be obscure like unbalanced rear wheels, or something else broken causing motion in the area, what I am saying is think out of the box to find the root cause for your chronic radiator problems.

[Terry W]

Dick,

The radiator in my '05 was replaced at the usual or at least common 63k mile figure, it seems 63-65 is the magic mileage number.

I got the WRV reinforced replacement from Burk Morgan. I believe he told me he doesn't know of any failures on the updated version. The shop guys said it was built like the proverbial "brick house" and they were very impressed with the new hangers. I also got the rubber damper info from Burk and had them replaced.

I would have to agree with Dave that there is an underlying issue, reusing the rubber dampers or some kind of hanger problem, misalignment maybe.

I know Alpines have their issues but it seems once they're taken care of it's a done deal. I don't know that I could hang in there like you have.

Please keep us posted as to the outcome and good luck!!

Terry

[Birddog Pilot]

Dave and Terry, thanks for the input. Yes, we bought the Alpine new in Jan. '07; so at least have the complete history of the coach. With each radiator failure I did indeed attempt to find the root cause of the problem, but I, and the maintenance facilities were never able to come up with any specifics. Although, I do not think in the case of the OEM replacement or the repair if the unit from Mac's that the top vibration mounts were ever changed - that's not going to happen this time around. The lower threaded rods are well shock mounted, but I suppose it would take an engineering study to figure out how top mounts could transmit destructive vibration to the lower portion of the radiator.
We are currently on a trip and didn't intend to be in the northwest dealing with major maintenance issues but decided that once and for all to hopefully get some answers and resolve the problem we would go to what we hope are the radiator "experts," Mac's who built the thing. We'll camp out there until someone figures this mess out. ETA Portland June 6...
BTW, some time ago someone conducted a study, either on our Alpine Forum or another section on iRV2, regarding the failure rate of the 2005-2006 aluminum radiators out of Acme and the average time-to-failure was extremely poor for all of the various coach manufacturers not just Alpines.

[Dudley do-right]

Hey birddog pilot; the picture by your post, is of course quite small, and also very dark, but I,m thinking is that a Storch?
Dudley Do-Right
2006 Apex 40MDTS

[Birddog Pilot]

Dudley, not quite a Storch, but a Cessna O-1F (L-19) Birddog; 1951 vintage, Continental
O-470-15, 213hp, with constant speed prop. Airplane was restored to flying condition after being wrecked by bush pilot in Alaska. I've owned it since 2000, and have brought it back to full Vietnam War era configuration as a USAF Forward Air Control aircraft with all radios and antennas, , target marking rockets (non-operational of course), along with complete repaint to represent a specific airplane that, unfortunately, was lost in combat. Like most of these projects it continues to be a "work in progress." It's a fun airplane but not even close to the STOL capabilities of the Storch.

[Hartsnet]

Dick

Did you get the info you needed on the vibration isolators? If not let me know, I just changed my radiator and in doing so found the isolators were installed upside down. I found a much better than OEM set of replacements. If you are still searching send me an email and I can give you all the info.

Jim Hart
hartsnet@yahoo.com

[wolfe10]

Jim,

It would be a big help to others if you post the "better" part number, where to get it and also what year/model your coach is.

Many of us keep a "what if" parts list.

Thanks.

Brett
2003 Alpine 38FDDS

[Hartsnet]

Regarding the radiator failures in 2004 -2007 Alpine coaches ( and a bunch other brands with side radiators as well).

My 2006 Apex radiator failed last fall, after a month of investigation I decided to remove and replace it with some help from a retired radiator guy who worked on big truck systems.

After removing the whole assembly called a “stack”, it was obvious why this radiator and probably many others failed. The hydraulic fan assembly weighs approximately 160 lbs , the radiator (dry) weighs approximately 140 lbs , the charge air cooler (CAC) weighs approximately 80 lbs , and the dash AC condenser weighs approximately 35 lbs. All four pieces are bolted together as one big assembly with the radiator carrying the whole load. The big mounting lugs welded onto the end tanks of the radiator carry all that weight (approximately 400 lbs ) to the steel structure where vibration isolators are used to dampen and protect from vibration. The bottom stabilizing rods (1/2” ready rods) are designed to stop any twisting or side pendulum action but do not carry any of the load. The radiator itself has 5 components: alum core, 2 end tanks, and 2 - 8” wide x 60” long alum channels. The core is attached to the end tanks by an epoxy process (not welded), and the 2 alum channels are bolted to the end tanks above and below the core and designed to mechanically connect the tanks but not touching the core.

My vibration isolators were installed upside down and allowed the big lugs on the end tanks to sit on the steel structure with only approximately 1/8” of rubber isolation.

I bought a replacement radiator from Burk Morgan in Yakima WA as well, he said the cores were welded to the end tanks not epoxied as in the OEM units and the whole thing appeared to be built heavier. I also found a two piece vibration isolator that is substantially better and will not fail due to compression from the weight of the “stack”.

Lastly I built a strong back that carries all of the load of the fan assembly as well as a small part of the load of the radiator, CAC and AC condenser. All four components are still bolted together but the bolts holding the fan assembly and the radiator together have rubber grommets to reduce vibration from the big hydraulic fan. The strong back bridges the whole “stack” assembly with the ends sitting on vibration pads on the steel mounting structure inboard from where the radiator is mounted.



If anyone wants to see drawings or other information send me an email at (hartsnet@yahoo.com)

[Birddog Pilot]

BINGO!!! You nailed it "Hartsnet," exactly what I am finding here at Mac's Radiators in Portland, OR. We too finally decided that the vibration dampeners were inverted and doing very little, probably nothing, to isolate vibration. Now whether that is the root problem, that is still open for debate. The technician doing my removal and replacement has been doing these motorhome radiators for over 27 years and says the problem is not necessarily only an Alpine problem; as he has seen the same failure point, lower right rear tank to core seam, on Alpines, Country Coaches, Beavers, and others with side-mounted radiators. To date, unfortunately Mac's has not been able to design-in a solution to their replacement radiators.

I will be emailing you more details on on my particular situation which we may be able to collaborate and provide further information to this forum.

All in all a perfect briefing, you did a wonderful job of relaying very important information.