Carb suggestions

[John Hofstetter <hofs@domain.elided>]

>lso-this is way off base, but you guys are the best mechanics I know
>and I need some advice.  A friend with a '90 Plymouth Voyager can start
>the thing, but it dies in about ten seconds even with the pedal to the
>floor.  I sprayed starting fluid in it and it died even when I was
>spraying the fluid as he was revving.  My thinking was that if it was a
>pump problem, it probably wouldn't even start.  I rationalized around
>this, but still think this is true.  I sprayed a ton of cleaner in the
>carb and moved the throttle and the next time he started it it lasted
>about thirty seconds before dying.  I think it probably needs a carb or
>rebuild, but don't want him to spend the money unless I'm more
>confident.  Any of you have any suggestions?  It's a four cylinder.  Are
>these carbs hard to rebuild?
>Sorry for the non-IH post, but I was working on both tonight, and was
>hoping someone could help!
>
>Michael

Michael,
First of all, I know nothing about Voyagers and for the most part don't 
work on anything made in this decade, but: Sounds to me as if you should 
check the gas supply by disconnecting the fuel line and let the gas pump 
into a can for a minute or so. If the gas pumps steadily, you know that 
the problem is in the carb or the ignition. When you pump on the 
accelerator pedal, you should see gas spray into the carb from the 
accelerator pump. Maybe this is the gas that lets it run 10 seconds and 
none is getting through the jets. Certainly a possible situation! 
Actually, when you pumped lots of cleaner into the manifold and it ran 
longer supports this theory rather than the problem being ignition. 
Good luck,
John H.