2001 Johnson 90hp

[captmello]

I'm going to look at a boat with a 90hp Johnson. I'm not an outboard guy so I don't know what to check.

Can someone give me some advise on what to check while looking at it. I may not have access to water, but I figure we could still run it for 10 seconds or so just to hear it run.
I have tools and a compression tester. I could do a compression test on the motor, if the owner allows me to, just to make sure the cylinders are close. What compression numbers should I expect?

Any help is appreciated.

 

[oldcatamount]

Re: 2001 Johnson 90hp

By all means, do a compression test on it. If the owner says no, then you should say no. I wouldn't run the motor out of water, even if it is just 10 seconds. All cylinders should be over 100 lbs. each and should be within 10 - 15%.

 

[captmello]

Re: 2001 Johnson 90hp

Thanks for the reply, I will insist on the compression test before any purchase.

Is the 90hp a V4? Is it considered a good motor?

 

[DJ]

Re: 2001 Johnson 90hp

Is the 90hp a V4? Is it considered a good motor?

Yes and yes.

 

[captmello]

Re: 2001 Johnson 90hp

How do I measure the shaft length? This motor is on a pontoon and I want to verify its a long shaft.

 

[oldcatamount]

Re: 2001 Johnson 90hp

A long shaft motor is 25 (+ or -) inches from inside transom clamp down to the cavitation plate.

 

[DJ]

Re: 2001 Johnson 90hp

Measure from the top of the transom to the mid line of the gearcase. It should be close (+/- 1") to 20" (long).

I doubt it's a short shaft. I've never seen a 90 short shaft. There is a possibilityt it could be a 25" but I doubt it.