| Ragusa Aluminum Pan Leaks...? [message #358759] |
Thu, 17 September 2020 23:07  |
 |
Richard RV
Messages: 631
Registered: July 2012
Location: Full-timer for 12 years, ...
Karma:
|
Senior Member |
|
|
At one point I had a continent coach. I could park it on clean concrete for a couple or three weeks and there wouldn't be a drop on the pavement when I pulled out. That's changed.
The leak(s) were bright red ATF showing up all over the sides and bottom of the Ragusa aluminum pan. Anytime an ATF leak is mentioned, people chime in about the porous aluminum in the Ragusa transmission pan. This seemed like a remote possibility in my situation as my coach had been drip free for a long time. I thought it rather unlikely that the aluminum spontaneously developed osteo-pan-orosis. But there have been quite a few posts about Ragusa pans having porous aluminum, so I figured it was time to change the filter, see what sort of sludge was in the bottom of the pan, see if the aluminum really was porous, and finally kill the ATF leaks.
I called Ragusa a couple of times and spoke with Ron Ragusa and his son Tate to ask about the pan return process and exactly how they tested their pans and covers. Ron said they pressure test the pans with 40 psi air and soapy bubbles (remind me to buy stock in soapy bubbles). All pans are tested this way before they are sent out to a vendor or individual. This is beyond overkill testing as the pan never really sees any pressure at all. If it fails the pressure test they send out a new one, and if it passes they send the old pan back. I asked Tate how many returned pans test good and are sent back to the owner - "Lots." Hmmm...this warrants more investigation.
I was parked over the Samsel's pit in Bean Station which made things easy. I totally degreased the bottom of the engine, transmission pan and final drive. A couple of days later there's ATF all around the transmission pan flange and dripping from the fins of the Ragusa pan. There was even ATF at the top of some of the tunnels between the fins. This was parked, hadn't moved and no wind had been blowing the ATF around and spreading it out. Okay, that settles it, right...?
Scrupulously cleaning everything on the bottom of the engine and dusting with talcum powder pinpointed the leak as coming from the vent pin hole.
Wally Andersen posted a picture on the GMC photo site that showed me where the hole is located. Until I saw his picture I thought it was coming from further up. The hole is not easy to see and probably covered with coagulated road grime.
The vent pin hole is located between the two seals on the shaft. If the hole leaks ATF the transmission side seal is leaking, if it leaks heavy gear oil the final drive side seal is leaking. The 1975 & 1976 Maintenance Manual X-7525 shows the vent pin in Figure 1 Section 3C-2
I cleaned around the vent pin hole with degreaser and then acetone, and applied a wad of butyl stickum over the vent hole as quickly as possible - ATF is a speedy creeper.
Two weeks and 800 miles later and there wasn't a drop of ATF anywhere on the pan. I was certain that there was a small leak at the driver's rear corner of the transmission pan. Nope, nothing at all.
I now know there's no reason to send my pan back to Ragusa, that'd just be wasted shipping cost and time for both of us, and I now know I have to replace the shaft seal on the transmission side of the final drive. I consider that a win-win: not chasing an imaginary problem and finding a real one.
But this brings up a concern. I'm concerned that a long time GMCer and GMC vendor, someone that stands behind their products and doesn't argue trying to deny their liability, whose products are all Made In America, and is just a super friendly guy, is having their products and reputation tarnished through anecdote and innuendo propagation. This bothers me and it should bother the GMC community as a whole.
Here's an example of what I'm talking about:
http://gmc.mybirdfeeder.net/GMCforum/index.php?t=msg&th=39755
The original poster got a replacement pan without any hassle, was told the pan they sent back was pressure tested and passed, and found out that the ATF leak was still there after the new pan was installed and coming from parts unknown. Another coated the inside of their pan and the leak was still there. And another found the leak was coming from the final drive gasket.
Please understand I am NOT casting aspersions or blaming anyone. We're all on this forum to help others with our experience, experiences and advice. Frankly, I think we do a hell of a good job. I'm also NOT suggesting that any manufacturer's products are perfect and they deserve a pass. I know that there have been some Ragusa transmission pans that leaked, but the problem is overblown. What I am saying is that the porosity is not common, and it's unlikely that a pan that is pressure tested to 40 psi with air is leaking ATF at ambient air pressure. Warm ATF molecules aren't smaller than air molecules, so temperature won't make a difference.
Jim K told me that the lion's share of returned pans pressure test as good. Manny said straight out that the Ragusa pans aren't porous. He said that most of the leaks come from the rear 3 bolts so he puts Viton O-rings on the bolts before installing them and tightens the bolts to only ~10 ft-lbs.
So it seems to me that the best advice we can give is to have someone who suspects a bad pan contact Ragusa or Jim Kanomata. They're the ones that can tell them how to best install the pan to avoid leaks, where the leaks commonly occur, and will stand behind the product if it does need replacement.
Richard
'77 Birchaven TZE...777;
'76 Palm Beach under construction;
‘76 Edgemont waiting its turn
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
