'85 Johnson 30hp No Power

[DuckFan]

I can’t figure out what to do next. I recently purchased a 85’ 30hp Johnson Outboard. It ran great the first few times I used it. However I notice it was not discharging water out of the water pump (pee hole) so I had the impeller replaced by a professional shop. After I got the motor back and went to use it. I noticed that when I put it in gear and throttled it up there was no power to the prop. It pushes the boat along like it is dragging an anchor. The motor idles fine and runs and revs up in neutral. Some one suggested bad gas so I replaced the fuel and hose. The engine seems starved for fuel when it is in gear and throttled up. Any suggestions before I take it back to the shop? Would cleaning out the carburetor help? Or Could this be a spark plug problem? Thanks

 

[Joe Reeves]

Re: '85 Johnson 30hp No Power

Duck.... You don't say what the time span was between when the engine ran fine and when the impeller was replaced. If there was quite a time span, the carburetor may be fouled.<br /><br />If there was only a day or so time span, I'd suggest you take the engine back to the shop and state that the engine ran fine previously, asking that they check to see if perhaps they may have accvidently dislocated a linkage etc, something of that nature.

 

[DuckFan]

Re: '85 Johnson 30hp No Power

Joe:<br />Thanks for the reply. The truth is that I tried to replace the impeller myself but could not get the lower unit off. I didn’t try very hard I got all the bolts off except the through bolt at the front of the lower unit. I was told that that bolt can stick and you have to heat and beat it off. So that is why I took it to the shop. I don’t know what they could have done to the carburetor. However I will call and ask them. Most likely they will say bring it in and the charge me for the repair. Something I am trying to avoid. It is possible I ran some bad gas through the motor. When I purchased the boat it came with 2 full tanks. I didn’t think of bad gas in them. Don’t know how long they had been sitting. Is it possible that the motor would run fine on bad gas for a while and then have problems? If the carburetor is fouled can it be cleaned/fixed easily? What about the fuel pump? I took the cover off and the screen is clean and it looks Ok. And suggestions you have would be great. Thanks again<br />DOUG

 

[Joe Reeves]

Re: '85 Johnson 30hp No Power

Doug... Do the basic checks. Engine not running, spin the prop and put the engine into forward gear, apply throttle and check to see if the throttle butterfly is opening full. Always possible a linkage got knocked off.<br /><br />Check the spark plug wires to see that they are both on the plugs. With the plugs out, check to see if you have spark that will jump a 7/16" gap. Possibly a plug got broke somehow (it happens).<br /><br />It's pretty close quarters between the rear hood latch and the plug wires... possible that one wire is shorting out to ground.

 

[DuckFan]

Re: '85 Johnson 30hp No Power

Joe:<br />Checked prop…Ok. Checked butterfly…fully opening. Spark plug wires were on plugs. I will check the spark though. I am also going to get new spark plugs, its time, and see if that helps. But I am afraid it may be a fuel problem. Would something in the carburetor get clogged up if I used bad fuel? How hard is it to remove and clean/rebuild the carburetor? I do consider myself mechanical but it seems these outboards have a technical nature to them that require special skill and I am afraid to really screw things up. They don’t seem to be like a car. <br />Anyway like I said in the beginning the problem is not that the motor won’t run it just won’t run fast. I have the motor on a 16’ aluminum boat and a 30hp should jump it out of the water. Instead I get a slow push. Kind of like something is holding the motor back from taking off. Further suggestions? Thanks<br />DOUG

 

[iRich]

Re: '85 Johnson 30hp No Power

Have you done a compression check on it? If so, what are the #'s?<br /><br />Rich

 

[DuckFan]

Re: '85 Johnson 30hp No Power

Thanks for the replies everyone. I am going to try some things. I think the only problem was a fouled spark plug. My question is could that have caused my power loss and still kept running as I described above?? If so I have changed the plugs and tested it in tank and it seems to be running ok. However it is hard to tell what kind of power it has in a tank so I am trying it out on the boat today. I will let you know. Anything else I should look for or try??? What if I still don’t have any power?<br />DOUG

 

[DuckFan]

Re: '85 Johnson 30hp No Power

Boy do I feel silly. <br />I fixed the problem with the power. Turns out it was the spark plugs. I put in new spark plugs (whopping $7) and bingo all the power I can handle. Thanks to everyone who replied and all the advice.<br />DOUG