Which carbs to use on my 1972 140 inline six?

[lilboatsman]

I have a 1972 Inline six that I'm working on getting started. The carbs that are on the motor right now have been sitting for years and leak a little gas when I pump the gas line bulb. Time for a rebuild, right?

So I also acquired with this motor another set of carbs which I'm assuming are off of a newer inline six. Those are the ones pictured. If I'm going to rebuild a set of them, which ones should I rebuild? These other ones look a little different, possibly off of a newer model?

Does anyone know when they started changing the carbs and if they have any advantage over the older ones? Will they still work with my motor?

Thanks.

 

[lilboatsman]

Re: Which carbs to use on my 1972 140 inline six?

Also, I was told that the extra set of carbs were in really good shape and could be used as is. I'm reluctant, but are there any checks that I can do on them besides just putting them on and testing them out? Maybe I don't even need to rebuild them?

 

[AMD Rules]

Re: Which carbs to use on my 1972 140 inline six?

Suitable decision would be to rebuild your current carbs. Not all inline six carbs are the same. The fact that you suggest those pictured look different than the carbs on the '72 140 you have would imply they are not meant for your motor. Also, the ones pictures are probably not much newer than yours. Pic is too small to see for sure.

What differnces? They could be meant for a 90hp motor, with smaller carb throats and small main jets. A water test could prove disastrous for your motor, by running lean and burning your piston(s) up. If they had the right jet sizes you'd be lucky.

Rebuidling your existing carbs isnt too difficult, and if you can get your hands on the service manual I bet you'll be pleasantly surprised at how easy it is.

 

[Chris1956]

Re: Which carbs to use on my 1972 140 inline six?

I also think you should reuse your carbs. New floats, inlet needles and gaskets should make 'em work like new. One of the changes to the inline six carbs was the backdraft carbs. Your '72 likely doesn't have this feature, which a lot will say is an advantage to you.....

 

[lilboatsman]

Re: Which carbs to use on my 1972 140 inline six?

If that's the consensus, then I'll stick with the originals, thanks for the help. I'm quickly learning that these motors are pretty finicky.

 

[cannonford57]

Re: Which carbs to use on my 1972 140 inline six?

even freshely rebuilt ,dont be suprised if your carbs dont "leak" a bit after squeezing the bulb.nothing wrong with them ,just the nature of the beast