A “gotta do” when you pick up one of these coaches……

The body structure of the GMC is most unique, 18 plastic panels and 5 huge aluminum sheets all glued together make up our flexible aircraft style construction.  There is no other vehicle built this way but as special as all that sounds there is a drawback that the average vehicle does not have.  These bonded panels all have seams where the panels mate together that have to be sealed to keep out rain.

Water leaks are a constant, vigilant matter.  AND there are seams that need periodic revealing.  Do you know any other vehicle that has serviceable seams?  Don’t get a headache there aren’t any.

Windows and even the window frames must be leak suspects and dealt with.  When buying one of these and wanting to do well for your baby, the cross seams at the front and back on the roof must be cleaned and resealed especially if they look like thisssorry, the pic came out sideways but this is a dissimilar material (aluminum and plastic) overlap seam that has no locking or sealing system other than the sealant put between the panels 45 years ago.  Over the years goopage and gobbing too has caused a mess like you see.

So you might think a coach with a roof seam like that is probably a pretty mistreated machine…….take a look at the interior of this twin bed AvionAs you can see, this is a well maintained nice coach recently purchased with our goal of bringing it back to the road mechanically ready to roll.  But it also must not leak rain all over this well kept interior.Of course it has fresh brakes and bearings, aluminum fuel tank and blocked off intake exhaust crossovers, a new double roller timing chain and FiTech fuel injectionbut along with the mechanical issues needing some love, we are also sealing the roof which includes the mentioned cross seams but also included are the top side railsT.his rail covers the actual sealing material under it.  45 years ago, butyl tape was used under this rail to seal screw holes, rivets and the roof perimeter seam.  Did it need to be addressed?  Rivets had let go under the rail and the aluminum roof panel was actually pulling awayypure certainly not supposed to be able to stick a tool up under the roof panel!  Rivets pulled out making a serious situationand talk about a leak hole……pull up any one of the 4 rail end caps held down by a single Phillips screw, here is what was under one on this coachThis coach actually had a piece cracked off and missing but where all those panels come together the is an opening on the joint you can put your finger into the interior of the coach!  Yours has this too…..and it’s sealed with 45 year old butyl tape!  It should have been resealed @ 10 years after production to keep the seal integrity up……..lets see, that would be in 1986… ………it time brother!

And the window sealing rubbers have shrunk and hardened up to be a leaker tooin 1976, GM wasn’t aware the fixed side window center bars needed to be pinned which caused the fixed glass to migrate causing a crack at the frameas soon as we have the roof resealed, the window frames and glass rubbers will be replaced and resealedSo picking up one of these classic machines, it need to not break down but it also can’t leak…..stay tuned, this puppy will soon be running with the big dogs!

Hey Ron, your motor is laced up into Mutcades and with a distributer stabbed…..we ride!Bwing able to actually load down and run a fresh motor BEFORE spending the 30 hours R&R is awesomeStay tuned…..Ron, I know it seams like things take forever but we don’t spend money to hurry up……your body is going in paint when the EM-50 moves over…..things are good……

Thanks for dropping by, a cold Florida day but that’s what jackets and socks are for…….. We will survive…..see ya later……

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