Thanks to all for the advice regarding replacing the heads on my '79 westy.
Unfortunately, after driving this morning for a few minutes and letting 
the bus sit for about an hour, I have been unable to get the engine to 
start again.  It turns over and speeds up when I depress the accelerator, 
but it isn't catching.  For the last few weeks (perhaps coinciding with 
the lower compression in cyclinder #1), I have had to give it gas to get 
it started.  But, it always did get started.  

Could the compression have suddenly gotten worse making it unable to 
start?  I have checked for spark and checked all the hoses and everything 
seems ok, and as I said, it started up fine this morning.  It looks like 
I'll have to have it towed somewhere, and if it is something to do with 
the low compression that's causing the inability to start, I suppose I'll 
have to be prepared to have the same shop do the head replacement job.  

By the way, the fuel filter is new, and the tank is full (filled up last 
night).  As I'm writing this, I'm thinking maybe funky gas????  It took 
12 gallons of fuel last night.

Well, any thoughts would be appreciated.  Also, if the heads need 
replacement, how do I convince the garage to use Mark STephens heads 
instead of something from a different source??  Some mechanics aren't to 
flexible in this regard.

Thanks again.

david