20 February 2015

The Seventh Circle of Vacuum Leak Hell

We re-diagnosed our problem, instead of blaming the AFM we decided it was a gross vacuum leak.
Kyle spent a little time checking things over but we spent most of the day away.  Sometimes you just need a weekend.

Kyle confirmed his suspicions that an injector seal hadn't been attached.  He also seal-all-ed a rubber elbow that I had noted as being fairly cracked and worn.  Aha!  Easy peasy, but...
Same symptoms persisted.  Kyle went over each vacuum line connection and still couldn't find anything.  It was cold out and when I finally warmed up, I became extremely lethargic - does anyone else feel like this after spending a lot of time in the cold?  At a total loss, Kyle finally consulted the Samba, then pulled out all the stops on trying to nail down this vacuum leak.

At lunch, Kyle picked up a fuel pressure gage and tested the fuel pressure that afternoon - everything was fine.  Kyle started methodically going through the manual for the fuel injection system.  It was ridiculously cold and miserable outside.  Not quite Michigan-bad (sounds like y'all had a rough weekend!) but no fun to be working on a bus.  We also pulled off a bigger hose with some cracks in it and treated it with our now-patented superglue / seal-all fix.  Symptoms persisted.
Kyle built a smoke device to send smoke through the vacuum lines and then look for smoke leaking out of any connections.
This resulted in a good deal of smoke pouring out of the oil breather.  Sighing in relief that we had finally found our problem (and kicking ourselves for not realizing the oil breather needed a seal on it!), we whipped up a cork seal and installed it.  The previous seal was disintegrated beyond recognition - oil gunk was keeping it sealed before we took the engine apart.  We started the bus up.  Same thing - ran fine until it was warmed up, then the rpms kept dropping until finally it died.  Curses.
At noon we hooked up the smoke device again.  It's actually a pretty ingenious little invention - Kyle bought a quart-sized paint can, attached a valve and a hose line, then ran a bike pump to the valve and a hose from the paint can to the vacuum system.  Make some fire in the paint can, put it out, then contain the smoke in the paint can.  The clamps in the photo are to keep the lid from popping off when the pump is being exercised.
This resulted in smoke puffing out of one of the the air plenum / injection manifold joints.  At one point back in our reassembly, we realized we had forgotten to install a tin, which led to a quick redo of one side of the engine.  In our haste, this intake sleeve curled under, and since it was on the bottom side of the intake manifold we didn't see it.
Kyle tells me it idled pretty well after that was fixed.  Eureka.

After I got out of work, we planned a test drive.  We made it as far as the end of the driveway - a small win, considering we hadn't tested the shifting system yet.  We'd had to jump it pretty frequently during our troubleshooting, but we chalked that up to constantly starting it, but not running it long enough to charge.  It was a little more serious than that.  Someone, in his infinite wisdom (shall remain nameless) didn't hook up the alternator.  So yeah.  Our battery was DEAD.
Hook up the alternator, give it one last jump with the Fit...now we're rollin'.

We planned a bar night - either to lick our wounds or celebrate our victories.  I can't even tell you how happy I am that it was the latter.  Kyle even drove the bus to Homegrown (I met him there later in my car). 

I'm spending my lunch hour trying to get this posted.  So far we've driven the bus to O'Reilly's, my work, and Homegrown Brewhouse.  I think it's finally time to call this a success...six weeks after pulling the engine out  in the first place.

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