Bog at WOT - '85 Johnson 150

I have been reading the various posts about bogging in order to fix my problem. Since there are various avenues to pursue I would like to post my problem to see which is the best course of action.<br /><br />1. Boat runs fine at about 75% of WOT.<br />2. When I get on plane and run at WOT it bogs after about 30 seconds. Problem started late last fall.<br />3. I cleaned my carbs with Sea Foam and put some in the gas to see if that helped. Changed my water separator filter. Took the boat out and it ran for about 15 minutes at WOT. Thought I had the problem fixed. Then all of a sudden the rpm's dropped. And the problem came back were it would not run at WOT, only for a short period of time.<br />4. If you pump the primer bulb it will stay at WOT better.<br />5. When running with the muffs, the gas level in the little filter on the outboard drops from about an inch to about a quarter inch in height. Is that normal?<br />6. Pulled the wires off the plugs one at a time when running with the muffs, and all responded with a drop in rpm.<br /><br />Am I having a air leak problem or a VRO fuel pump problem or other? Sorry for the long post.

Re: Bog at WOT - '85 Johnson 150

7. I also removed the gas cap when running and does the same thing. No clog in air vent.<br /><br />Thanks.

Re: Bog at WOT - '85 Johnson 150

I had this my hose from the fuel tank was to long and thin it was collapsing at WOT<br />had to get a thicker walled hose.<br />(3/8 walled hose)<br />megclay

Re: Bog at WOT - '85 Johnson 150

Thanks Megclay. I have had the same hoses on for years and its pretty heavy duty. Problem only recent.<br /><br />I pumped up the bulb and cannot detect any fumes in the outboard area, so I thinking no air leaks on that end. How do you check the suction side? My fuel line runs under my deck to the fuel tank. How do you go about checking/replacing that?

Re: Bog at WOT - '85 Johnson 150

My lines wer 25' long had to fish it through<br />using the old bad line.<br /><br />use can use spray starting fluid to check for leaks in the motor lines.<br />be careful

Re: Bog at WOT - '85 Johnson 150

I am going to try a portable fuel tank to see what happens.