Wrong carb on engine?

Hello. This is my first post/question on the forum so take it easy on me if I posted in the wrong section or missed a post already addressing my concern.

That said, I recently purchased a used 1989 Rinker Captiva 186 with a 4.3L Mercruiser engine. I was rebuilding my carburetor this weekend when I noticed the model # (864940) on the carb is actually for the 3.0L engine!! The Mercarb # for the 4.3L is 864941... at least according to my manual and other sites I've checked.

My question is, is it possible the carburetor for the 3.0L is interchangeable with the 4.3L or did the previous owner mistakenly put the wrong carb on the engine at some point?

Asking because I broke the carb housing during the rebuild and decided to purchase a new one... I ordered the same model # that was on the boat, but now wondering if I should have ordered the model # for the 4.3L.

The boat seemed to run fine when I first got it so I know the 3.0L model works just wondering if I'm losing power/performance by going with the same carb.... or if this could actually cause greater issues with the engine.

Any insight would be greatly appreciated!!

Thanks,
Travis

Re: Wrong carb on engine?

A carb setup to supply fuel to a 3.0 will cause a lean condition with a 4.3 with the jets not being large enough. They may fit but your engine will suffer, suggest getting the correct carb. I looked up a general (no knowing your serial number) 3.0 and 4.3 for 1989 and came up with the following:
3.0 - 807764A1
4.3 - 860070A2

Re: Wrong carb on engine?

AllDodge said:

A carb setup to supply fuel to a 3.0 will cause a lean condition with a 4.3 with the jets not being large enough. They may fit but your engine will suffer, suggest getting the correct carb. I looked up a general (no knowing your serial number) 3.0 and 4.3 for 1989 and came up with the following:
3.0 - 807764A1
4.3 - 860070A2

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Thanks for the reply, AllDodge. My serial number is 0C460393. It's 175HP... Sounds like I'll need to go with the 4.3L carb, but let me know if the serial number changes anything.

Re: Wrong carb on engine?

txtrav said:

Thanks for the reply, AllDodge. My serial number is 0C460393. It's 175HP... Sounds like I'll need to go with the 4.3L carb, but let me know if the serial number changes anything.

Click to expand...

The OEM Mercury list it as 9565A 1 new part number
The other number is the old part number

Re: Wrong carb on engine?

AllDodge said:

The OEM Mercury list it as 9565A 1 new part number
The other number is the old part number

Click to expand...

Thanks for looking into this!

Re: Wrong carb on engine?

txtrav said:

Thanks for looking into this!

Click to expand...

Ayuh,... Welcome Aboard,.... Bite the bullet, 'n toss a 4 bbl. carb, 'n intake on it,....

It'll bump it to 205hp,.....

The Edlebrock carb on an iron manifold is a nice set up,....
'bout same as Merc's,...

Re: Wrong carb on engine?

Bond-o said:

Ayuh,... Welcome Aboard,.... Bite the bullet, 'n toss a 4 bbl. carb, 'n intake on it,....

It'll bump it to 205hp,.....

The Edlebrock carb on an iron manifold is a nice set up,....
'bout same as Merc's,...

Click to expand...

Now THIS sounds enticing, but also beyond my skill set. I'm more of a swap-n-replace kind of guy. Heck, I couldn't even do that right which got me in this pickle in the first place :facepalm: