<VV> Followup to engine cutting out

[Bill Elliott]

(snip)  I removed the rubber diaphram and piston and found the
>inside had a large amount of metal chips and powder in it.

(snip)
> 
>   From what I have read on the list over the last 10 years the only
>failure mode of a Corvair Fuel Pump is tearing of te diaphram and
>leaking of fuel. I have never heard of this type of failure. Has
>anyone seen this? 

(snip)

For what it's worth, in cars that have sat for long periods I have found large amounts of this 
"powder". Even when I use an additional fuel filter, it seems to gum up the fuel pump and plug up the 
main jets in the carbs. Since I deal with a large number of cars that have sat for long periods, I think 
this has added to my long list of pump failures.

(Interestingly, I don't see this powder in cars that have sat for decades.... I'm convinced it's 
something to do with modern gas.)

However, I've not seen metal chips....

Also, check valve failure is another form of fuel pump failure and seems to be more common than 
usually reported. We hear about it when the pump fills the crankcase with gas, but I doubt that most 
failures do that.... I'll bet when a pump quits pumps but doesn't leak fuel, it's a check valve failure.

I have a pump like this myself I intend to take apart and possibly replace the check valve with a good 
one from a pump wth a torn diaphram.

Bill Elliott
Urbana, MD