How to tell if carb needs rebuilld??

[sebas54]

I have a 1987 gm 4.3l merc. alpha1. Two barrel carb.

When I give it gas too fast it stalls. Is the only way to check the carb is a fuel pressure test?

I have a similar thread explaining more but I want to know how to tell if the carb is bad.

Thanks

 

[abj87]

Re: How to tell if carb needs rebuilld??

Yup sounds like a carb issue, specifically the accelerator pump with in the carb. at 22 years old it probably needs a rebuild anyway.

If you have any mechanical skills i would try rebuilding it your self. Its most likey a Rochester or a Mercarb which are very simple and can be rebuilt with only a butter knife!!!

 

[sebas54]

Re: How to tell if carb needs rebuilld??

I have the seloc manual and I do have some mechanical skills. Besides the rebuild kit do I need anything else?

 

[mkast]

Re: How to tell if carb needs rebuilld??

A better manual.

 

[Bondo]

Re: How to tell if carb needs rebuilld??

Besides the rebuild kit do I need anything else?

Ayuh,... A pail of Carb Soaking fluid,... Some very tiny brushes, access to compressed air,+ Patience...
And,...
The Odds for success is about 50/ 50...

Old Carb castings are usually corroded, dirty, worn out,+ generally Beat after 20 years of abuse,+ repeated doucings of Water,...
Saltwater in many cases...
There's alot of tiny passages that really can't be cleaned, muchless inspected...

Good Luck with it whichever way you go....

 

[Expidia]

Re: How to tell if carb needs rebuilld??

Funny you said that Bond-o . . I just made the decision to just replace the carb on my new to us 1999 25 hp Merc 2 stroke just for the resons you outlined.

My choices were: but a rebuild the OEM kit $85 and do it myself or let a Merc dealer rebuild build it at $90 an hour plus the cost of the rebuild kit.

Or order a new OEM one for $285.

I went with the OEM new one because I too was worried about wear on the inside passages that I knew I could never get at even with soaking.

I figure I'll clean up the old one without using a kit as best and sell it on Craigslist for $100. This way the new one actually winds up costing me about $100 because I would have had to but the rebuild kit anyway.

At least I know I won't be having future carb issues after I would have done the rebuild myself.

Now if I had a multi carb motor I would have had to go the rebuild route.