Carb Swap or Rebuild?

[kanteen]

Was wondering if anyone could recommend a replacement for my 2BBL Mercarb (97 4.3lx Gen+) I've found a few places online that will rebuild them, all seem to be in the $200-$250 range, which I think is bit pricey, until you see what a new Mercarb runs. I'd rather not send mine in to be rebuilt in the off chance it takes all summer. I'm gonna stick with a 2BBL, but I also found a Rochester on ebay that looks to be a regular ol' GM part, converted to marine use. I'm drawn to that because it should be easier to rebuild in the future if needed. Anyone have any experience with these? I'm curious if any modifications are needed on the fuel supply or throttle cable? I'm also curious as to just how "marine" these carbs really are. If anyone has any experience with them i'd appreciate the input.
Thanks

 

[batman99]

Using lots of U-Tube videos as examples, I always rebuild my own engine's carbs. And for needed parts, I buy the gaskets, needle/seat and other parts from iboats store. Saved dollars on labour allows me to buy other needed items / upgrades. :joyous: As suggestion, rebuild (clean) existing carbs. Most often, they need serious cleaning - due to junk / gunk from ethanol diluted gas. I'd clean existing carbs first - before replacing with new expensive replacement.

Hope this helps.

 

[Bondo]

I'm also curious as to just how "marine" these carbs really are.

Ayuh,.... Welcome Aboard,.... Marine carbs are vented very differently,....

The entire Fuel System, right from the tank is Marine different,....

Attachment points, 'n methods, as well as chokes change 'tween applications, Marine, Auto, or whatever,....

 

[kanteen]

Thanks. Actually, I was wondering about the 2BBL Rochesters you can find on eBay. They are obviously converted to marine application, and I was wondering what that means in practice. IE...did the seller actually do anything to make them seaworthy.

 

[nateo]

I researched this extensively last summer. There are specialty shops on ebay that will hotswap i.e. they will send you a rebuilt first. They give you credit when you send yours back. After taking mine apart myself I realized that it was in pretty good shape, possibly rebuilt already at some point. I put new gaskets in and reinstalled. My problem ended up being that the idle fuel air was not set properly. This turned out extremely easy to fix, just set mine to 2 and half turns from bottom, then adjusted timing properly. My boat ran great rest of summer.

Why are you thinking total rebuild? The "basic" rebuild kit comes with new gaskets and I couple of parts (a float if I remember correctly). Total rebuild is often a lot of parts and may be overkill.

 

[stonyloam]

IMHO replacing your Mercarb with an unknown quantity like a "remanufactured" Rochester would be unwise. Chances are all your carb needs is a good cleaning. You can buy a rebuild kit for about $35 and a carb dip cleaning setup for about $20, and do it yourself. The Mercruiser manuals have step by step instructions. It is really pretty easy to do. Good luck

 

[nateo]

I'm going to create a term for this. "a soft rebuild". Carb cleaner, new gaskets, and tune. about $10.

 

[Fishermark]

... I'm drawn to that because it should be easier to rebuild in the future if needed. ...

A Rochester is not any easier to rebuild than a Mercarb. Both are pretty easy - and parts are available for both.