Help, my 4423’s rubber gas cap is melting

[skanders01]

Just acquired a ‘4423 in awesome condition. Good spark, 90+compression, cosmetically great. New gas and a with a little coaxing it started and ran pretty good. Fast forward 3 weeks and it didn’t want to start. Still good spark and compression, so, logically I thought fuel. So I pulled out the cap and noticed the rubber was softening/deteriorating badly. After being in the fresh air overnight, it is now hard and brittle. I also removed the tank, shutoff valve and fittings and cleaned them. Valve was full of what remained of what I believe was an intake screen/filter. All cleaned up now, and ready to try again.

Anyone else have this problem with their ‘4423? First I need to fix the gas cap, then before reassembly, I was reluctantly wondering whether or not there might be an additional rubber in contact with the fuel that might also be deteriorating. Hate to fix what isn’t broken, so, again, anyone with similar experience with similar issues?

Not the best picture of the cap, but if you are responding you have seen it before. Looks like I have to fix the date stamp on my camera.

Thanks in advance for any support.

Kyle

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Attachments:

Kyle Anderson
Trempeleau, WI
skanders@triwest.net
920-764-0501

[frankr]

Somebody is certain to blame it on incompatibility with today’s gasoline. And they just might be right.

[garry-in-michigan]

Just after they came out in 1948 it was found some fuel additives would dissolve the plastic filter bowl and fuel gage. They switched to glass in the later models. Check for a rubber expansion chamber in the bottom rear starboard of the fuel tank. This was also eliminated in the last models. . . 😆

[2fast4me]

Mine had an O ring on the sediment bowl that turned to JELLO. The gas stations in Wisconsin did not have any fuel that was Ethanol free at that time. I switched to Aviation LL for a time. Yes I did blame the Ethanol blend that was forced on us. I feel better now.
Jim

2Fast4Me

[brian]

I had a 4423 that almost convinced me that outboards are not made to be serviced. Of all the outboards I’ve worked on that weren’t intended to actually run, this is the only one that kicked me right into tomorrow. I swear that gasoline gets lost in that carburetor before it has a chance to reach the crankcase. Dealers must of hit the bottle after a look at that mess. Mine ran for maybe 30 seconds before the rubber parts took on gas and doubled in size. I hope you get a chance to get it running as I have never seen it happen.

[garry-in-michigan]

A clip taken of a bad movie of me running mine at a meet . It would plain the boat when I sat in the middle neat. . . . 🙂

[Mumbles]

The 4423-25 caps seem to shrink and distort with time so what I did was make new ones out of black Delrin (Acetal). It was trial and error turning them but they fit the tanks grommet snuggly now and don’t leak. I can’t find any photos of them but a buddy with a lathe could make one up quite easily for you. A box of Bud in return would make it a ‘flat rate’ job.

[Author]

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