1983 Johnson 140 hp

[samsuncam]

I have a 1983 johnson 140 hp that has 135 psi compression on all
4 cylinders.The motor looks really nice.I am going through
her now and found out that the carbs are the old style 90 hp
type.The part number is 325416 on the carb top.
Im wondering if using this motor with these carbs will damage
the engine.
Thanks,Sam

 

[Dhadley]

Re: 1983 Johnson 140 hp

As long as they still have the stock 90 hp jetting that was in them from manufacturing they'll be just fine. And are clean of course.

 

[samsuncam]

Re: 1983 Johnson 140 hp

Thanks for the help.I will check to make sure the jets are the factory size.
I assume if my carburators have the jets for a 115 hp motor installed
that it would create a problem of some type? If i happen to unforunately have
the wrong jets in my carbs is their a place to find original 140 hp carburators.
Ive looked around and havent seen any.
Thanks,Sam

 

[lexer440]

Re: 1983 Johnson 140 hp

You could try,

http://epc.brp.com/SiteMods/BRP_Public/BRP_Public_Login.aspx?ReturnUrl=/Index.aspx

or

http://www.marineengine.com/

I have used both and both are very good.

 

[Dhadley]

Re: 1983 Johnson 140 hp

Crossflow carbs are calibrated (jets being part of calibration) for the air they flow, not for the horsepower motor they are bolted on. That's what is so great about swapping them around to make the motor react differently.

 

[samsuncam]

Re: 1983 Johnson 140 hp

Thanks.Now i understand the carburator issue alot better.
I was a little confused on the application and calibration
of the carb.I like the idea of being able to change around
carburators.Thanks for the links for parts.
Now to find a boat for her.Ive been thinking of one
of those sea barges.
Thanks again and GOD Bless

 

[emdsapmgr]

Re: 1983 Johnson 140 hp

The carbs are built with different throat sizes, the larger the throat, the more air/fuel they will flow and make more hp. The carb throat is cast into the front flange face of each carb, such as 1 3/16", 1 5/16", 1 3/8" etc. That engine probably came with at least 1 5/16" carbs on it from the factory.

 

[samsuncam]

Re: 1983 Johnson 140 hp

Thanks.I was curious on what the numbers were.Mine says 1 5/16.
Would this size be for the 90hp carb.Im starting to second guess
that i even have the 90 hp carbs
Thanks for that info

 

[emdsapmgr]

Re: 1983 Johnson 140 hp

I would think the 90 carbs would be either 1" or 1 3/16". Your engine should run strong with those larger carbs.

 

[samsuncam]

Re: 1983 Johnson 140 hp

I have a quetion.I want to make sure the jets installed are the correct size.
I noticed that my carbs are the old style after looking them up. The number thats cast on
the top of my carburator is 325416.The number cast on the front is
1 5/16. Any ideas on what i have.

 

[emdsapmgr]

Re: 1983 Johnson 140 hp

The number from the top of the carb is typically a casting number and may not go anywhere when compared to a parts list. Over the years, OMC put many different size jets in carbs which had a 1 5/16" stamped on the front. Their internal designs changed over the years, so again it's hard to tell. Why not go out onto the web to the original factory parts list for your 1983 engine and check what it was supposed to have in it. Compare the factory listing with what is actually in your carb. You can check all your parts on the Bombardier website: epc.brp.com.

 

[samsuncam]

Re: 1983 Johnson 140 hp

Thanks,Ill do that.Thanks so much for your help.
I still have alot to learn.I cant wait to get her running
and find a boat for her.
Thanks and GOD bless you all!
Sam

 

[sd18]

I have a 90hp 1983 Johnson that seems to be dropping a cylinder at idel speed but I am having a little trouble sync it

 

[sd18]

I have a 90hp 1983 Johnson that seems to be dropping a cylinder at idel speed but I am having a little trouble sync it

 

[jakedaawg]

SD18, start your own thread.

 

[emdsapmgr]

I am thinking that you may have an older 135 V4, instead of an 83 140. The 135 compression was more typical of these early 135 engines than the later 140's.
Can you post the model/serial numbers from the casting plug on top of the block. It's stamped into a core plug about the size of a quarter. It's painted over, but should look like this: The 135's had only a single vernatherm (thermostat), whereas the 140's had two thermostats. The 135 carbs had choke butterflys, the 83 140 used a fuel primer system for the choke.