GMC Motorhome, why consider a timing chain, it runs…

Morning guys, this morning I want to show you how things happen here working on late 30’s machines.  This coach came down from Arkansas, the owners planned a week with their long time friend and left their coach with us to do a looksee.  Why do I feel it felt like watching the beginning of a Gilligan Island episode…..  See this is how it starts and it’s no ones fault….. this coach made it down from Arkansas without mishap… true the motor wasn’t idling well and because of that the brakes were smoking because he had to idle it high to stay running….. hey but it made the trip.  I mean how much wrong could there be and certainly a week should get it tweeked to a T since it obviously already runs…. well?

So like the song “Big Bad John” …. with picks and shovels we started back down…..  brakes were first since we know they were smoking, pulled the carb and had it sent off for a reman.    I take it back, there was one problem on their trip… see the black roll on the roof?  The awning started to fall off on the trip, they yanked it the rest of the way at an RV park but they wouldn’t let them throw it away in the dumpster…. too long…. so it got strapped like luggage on an overland stagecoach!  We’ll cut it up and toss it…….  anyway, we had put a weeks work on brakes, the engine, dash AC, cool new radio and some other stuff on his list enough to make the drive from Arkansas cost effective but doing some road testing the coach just would not idle smooth.  For the heck of it, I installed another remaned carb. to substitute… u know, just in case…. no difference..

Always looking up to make sure my sky doesn’t fall I suggested there may be a loose timing chain.  Originally we all thought maybe bad gas.  So we have a … to this point… descent running original 455 motor….. the key is “original” because you remember John’s coach and his original engine loose timing chain    I had to bring this up in our confab about what to do… their friends offered their place for a little longer so the decision was made to replace the timing chain and gear set.  Now we’re really pushing the time… we want to impact the owners plans as little as possible but we’re looking at a good 15 hours labor IF everything goes great…….. never depend on great and sure nuff, removing the “cow catcher” screen deal … I KNOW a mod from some previous owner….  no one could tell the condition of the radiator until it was out    Well, that wet spots not a good sigh but look closer in the corner .and then just above that and then a little to the left…..  The blacksmith did the best he could do to keep the coach running… and to his skill, it was not leaking at all until we touched it and what we found was well….. it can’t leave.  Calling Pat and texting a pic the future was clear.  Now it’s rubbing the shoulders of our radiator shop to move on this……. 

Good call guys, going in for the timing chain was the trouble   I feel we just dodged a howitzer shell!  Was the timing chain loose?    Take a closer look at the lower gear with the chain hanging down over 1/8″      Heck, the TEETH aren’t much longer than that!  That chain was about to jump time…..  This is an original plastic tooth, single row chain.  John’s chain was loose but it was still on the gear…. this is the loosest chain I have seen on a running motor.  And THAT’S hard to say!

Guys, if you have an original motor…. hey, there are piles of them out there, these are great motors…. but if it’s original it HAS to have close to 100K miles and even a low mile older motor could probably improve it’s performance with a new chain….. Pat’s coach for sure and going that deep finding other choice problems like holes in an original radiator, original style oil cooler hoses…. you can see the steel line/ hose construction   and already patched original 5/16″ tranny cooler lines…. you can see our fiber armored blue one piece oil cooler lines already connected to the tranny when the fresh recored radiator comes in today.

So lets all think good thoughts for Pat, hoping no other bad things come up and we’ll have this together today.  Ouch… quitit…..  hey, sometimes you gotta get-r-done! 

Stay tuned I’ll try and post more this evening… it looks like a long nighter tonight,,,,.

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