Sign in to follow this  
Followers 0
EricF

Outboard question....

Rate this topic

7 posts in this topic

....I'm a hull/glass/general boat guru....only moderately engine knowledgeable.

 

I have 2004 Johnson 90HP Two Stroke. I bought it new in 2004. Never had a lick of trouble other than your normal water pump change, thermostat change, unit oil and plugs. Here's my issue:

 

The last few weeks I have developed a fuel leakage around the upper port carburator (4 carbs). The fuel is leaking from the bowl gasket when the sun heats up the engine sitting on the trailer. Just enough to run a line down the lower unit as it drains from the cowling...every day. The gasket appears to be cracked, etc...just worn out so to speak. I've loosened the screws and resnugged them...and notice that the gasket pressed out when I do so.

 

Here's what I'm doing:

I ordered, and should have this week, four carb rebuild kits...includes floats, gaskets, etc.

 

Here's what I've been told:

-The float is sticking OR the needle valve is sticking on that carb, allowing the bowl to fill too much...then expanding during the heat of the day.

-It's time for a carb regasket, new floats, etc...typical maintenance on that engine.

 

I'm going to rebuild the carbs (I don't have a problem doing that with my knowledge and experience). Do any of you guys have insight into this...OR...have you experienced it???

 

Thanks!

Share this post


Link to post
Share on other sites

very simple to see if the float is not working, OR if the needle is stuck. Do you have a "primer" ball in-line with your fuel hose? If so, take the cowling off, watch that carb, and squeeze the ball. If possible, tilt the motor up so the fuel would drip Forward and away from the engine. Squeeze the ball, if gas comes out, float is bad, or needle is stuck. If you squeeze and squeeze, and squeeze, and you don't get a drop, nothing is wrong. It could be just the seal.

Share this post


Link to post
Share on other sites

that has plastic carbs on it, they warp and leak all the time, changing the gasket usually fixes that, I actually just did a set today at work with the same problem, be careful if you do the floats etc that you don't set them too low, you want them to be pretty much level if you hold the carb upside down

Share this post


Link to post
Share on other sites

Finished the job today...actually fairly simple. I did however, have to go back up town to pick up a bowl. It seems these plastic bowls will warp as "freebie" said. The one that was causing me trouble was warped and would not seal, even with the new gaskets. So I just sprung for four new bowls and did all four carbs. Saved myself a couple hundred in labor I'm sure...and spent a grand total of 180 buck on four rebuild kits and four bowls.

 

repainted lower leg while I had the cowling off again.

Share this post


Link to post
Share on other sites

Update:

 

As is always the case...it runs like a champ on the trailer. Put it in today to go do some 'sun time' with the woman...God, I love it when she's in the 'kini.drool.gif Anyway, it won't come up over about 1200 rpms...then starts bogging. I'm thinking, "Man! Gotta be the floats." I'm thinking I set them wrong or something. So we "putt putt" over at idle speed a couple miles to a decent hangout...I drop the hook...pull the cover...nothing visibly out of place. I sat for a few hours wanting nothing more than to run home and tear it apart again. Back at the house...I pull the carbs again...simple, less then twenty minutes. Take a look and see everything is in place...I know I couldn't have screwed up something else in the process...so, just in case, I put the old floats back in (remember, my only problem was a leaking gasket, figured the floats should be okay), then inspect everything else...all good. I snap it back together and put it on the hose with the cowlings off and it runs okay...of course. Then I see it!!!!! Like a lightening bolt from a darkened sky...bam! The fuel hose is kinked to he// and back. Seems the Bombardier fuel hose, three foot section, that connects to my "real fuel hose" in the boat...is deterioted and collapsed..spongy to the touch...and just plain shot. I run up to the harware store and pick up a new section of hose and install it.

 

Moral of the story: It HAS TO BE this fuel hose...it was sucked completely flat almost, as I idled on the trailer. In the water, in ran fine until I gave it throttle. The rpms would increase nicely, then a second later go to bogging...so I'm figuring the flow of fuel through the hose was just not enough to keep it up. Let's hope...tomorrow morning will tell.

 

Talk about a coincidence!!!! The leak is gone though!

Share this post


Link to post
Share on other sites

could be ethanol damage, it damages the hose from the inside out so you can't see it... newer hose is ethanol safe.

 

Sometimes those carb bowls warp if you tighten them too much.

they can be dressed on sandpaper on a flat surface, just swirl the bowl around in figure 8's lightly to knock the corners down.

 

Best fix is metal bowls though.biggrin.gif

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to register here in order to participate.

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0

  • Recently Browsing   0 members

    No registered users viewing this page.