Johnson 1997 spl

[Shane7]

Alright I've got a Johnson 115 spl v4 the powerhead is shot as a piston ring broke I also have a 90hp v4 from about 1984 I don't know the model number plate is gone I was wondering if I can use this powerhead on the 115 with the carbs off the 115 and produce 115 horsepower or is there something else I would have to swap over also like the heads I assume they will bolt together without problems but wanted to ask first

 

[boobie]

Re: Johnson 1997 spl

You should check shop.evinrude.com and compare part #'s. If ther're both bubble backs it may work.

 

[Shane7]

Re: Johnson 1997 spl

How do I check part numbers without a model number also where would the part number be located on the block

 

[Shane7]

Re: Johnson 1997 spl

Also both are not bubble backs

 

[Solittle]

Re: Johnson 1997 spl

Look on the block for a round disk that looks like an automotive freeze plug. The model number should be stamped on this plug unless the engine has been overhauled.

I suspect that there is more to it than you may think.

 

[Shane7]

Re: Johnson 1997 spl

The 115 has this it matches the number on the transom bracket but the 90s is blank so I don't really know what it is because I got it with a 140 hood on it

 

[Shane7]

Re: Johnson 1997 spl

The 140 has c8246756 on its frost plug

 

[emdsapmgr]

Re: Johnson 1997 spl

Your 115 is a bubble back (high performance) block. The older 90 is a flatback (basic engine) block. The 90 won't make the hp that the 115 does. You may be able to put the 115 carbs on the 90 to get some add'l hp out of it, but it won't be 115. Also, the 90 hp engine was originally hp rated at the crank. The 115 is hp rated at the propshaft, so to compare the 90 with the 115, you'd have to reduce the 90 hp by 10% or so to have an "apples-to-apples" comparison.

 

[Shane7]

Re: Johnson 1997 spl

Yeah I know Its because of porting in the block but what I want to find out is if it is a 90 or a diffrent motor does anyone know how to find out with the Frost plug number