Posted by jim lee [172.68.142.44] on Tuesday, January 23, 2018 at 00:32:48 :
Took the truck on a long range test run today. The plan was to head up Mt Baker Highway to Welcome Market for a Burger Patrol. This was mostly to see how the machine runs over an extended period. We've not yet run the machine more'n maybe 20, 25 minutes from home.
About half way there, turning onto highway 9 in Sedro Woolley, Julie is asking "You must be feeling pretty confident taking the truck this far."
"Yeah. Well, there's not a lot I've not gone through.. What's that sound?!"
"Snick snick snick snick snick.."
It sounds kinda' like maybe a blown exhaust manifold gasket? Or, God forbid, a blown head gasket? Something rubbing on a spinning something? It follows the engine RPM. Clutch or shifting has no effect on it.
So I turned around and headed for home. Back at the shop I took out my trusty ultrasonic vacuum leak finder. Somewhat like a microphone on a stick with headphones. Fired the truck up, and the noise was gone.
Grrr!
Seeing that the truck fixed itself, I took Julie out for her first crash box driving lesson. And the noise came back! Even using the leak finder, I can't find the source of the noise. It seems like its from the driver's side of the engine, but for the life of me I can't locate what's causing it. Generator sounds fine, water pump sounds fine, distributer sounds fine. Side of block sounds kinda' cool with everything going on in there. But fine none the less.
So I figured I'd toss it out here to see if anyone had any ideas.
Many thanks in advance!
-jim lee
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