Mercury 9.8 stuck in forward gear

Tex Red

Recruit
Joined
Jun 14, 2010
Messages
5
I was out on the water last night when my motor stumbled and then just died. My first thought was that the vent on my gas can was closed but it was open. It was then that I noticed that the motor was smoking a little bit. There wasn't anything burning but the motor got really hot. I hadn't noticed this was happening because it was dark and I was focusing on trying to find the channel markers. I had only been going about half throttle the whole time. At that point I wasn't able to try and run it again because it was stuck in forward. I still can't get it to go into neutral. I can get the motor to turn by turning the prop. If I turn it the other way I get a clicking sound. When use the prop to turn the motor over it makes a shreeking sound - like metal and nylon/plastic rubbing. It doesn't sound like metal on metal.

So, here is what I need help with:
1. Why did it get so hot? Is that why it stumbled and died?
2. How do I get the shifter unstuck?
3. Do I have a problem in the lower end?

I am a shade tree mechanic, but I know nothing about outboards. Any help ya'll can give me would be great.

Thanks
 

huntin dawg

Petty Officer 2nd Class
Joined
Nov 12, 2009
Messages
197
Re: Mercury 9.8 stuck in forward gear

Don't know about the stuck shifter but it sounds like it stopped pumping water and seized up. The shreiking sound is probably bound metal, piston to cylinder. You probably scored the cylinder up pretty good. The prop should click when you turn it clockwise and engage when you turn it counter-clockwise so that sounds right.

HD
 

Jacket4life

Petty Officer 1st Class
Joined
Apr 22, 2010
Messages
382
Re: Mercury 9.8 stuck in forward gear

So, here is what I need help with:
1. Why did it get so hot? Is that why it stumbled and died?
2. How do I get the shifter unstuck?
3. Do I have a problem in the lower end?

I am a shade tree mechanic, but I know nothing about outboards. Any help ya'll can give me would be great.

Thanks

It got so hot because my guess is the impeller is no good. I would further venture to guess you have owned the motor for a while and never replaced it. Yes, that is why it "stumbled" and died. Althought the "stumbling" in this instance was very likely fatal.

Theoretically, it sounds as if you do not have a lower end problem, but I am unsure why you are stuck in gear. I think it probably doesn't mater if you melted the piston anyway. Take the plug out, get a good flashlight, and turn the motor over by hand until you can see the top of the piston. If it looks bubbly, you're done. Time for a rebuild. If you can't see it, or are unsure, do a compression test (doesn't matter still if you are stuck in gear, just watch out for the prop). If it is less than 90 PSI, again, you're done. If all seems well with the engine, then pull your lower unit and replace the impeller, at least! This should be done annually!
 

Tex Red

Recruit
Joined
Jun 14, 2010
Messages
5
Re: Mercury 9.8 stuck in forward gear

Thanks for the help. I have been out of town for several days, so when I get home I will check it out. I have only owned this motor for a couple of years and I am not familiar with its past maintenance history. Also, this engine has never allowed me to turn it over with the pull cord while it is in gear. With that in mind, should I do the compression test by turning the propeller over by hand? Also, the skreeching sound was come from down low, not up high around the cylinder - if that helps.

Thanks again for your suggestions.
 

Tex Red

Recruit
Joined
Jun 14, 2010
Messages
5
Re: Mercury 9.8 stuck in forward gear

I have finally gotten back from traveling and have been able to take the suggestions above and have gotten a lot figured out. First, the reason it was "stuck" in gear was really simple - I got it out and won't have that problem again. Second, I was able to get it to turn over very easily so I did a compression test. The top cylinder was about 90 lbs and the bottom was about 105 lbs. I looked in at the cylinders the best I could and nothing looked too bad. I am still not sure exactly why it stumbled but the fact that it did kept me from ruining the engine. Third, I took the lower unit off and the impeller was in a hundred pieces. I was able to slide it off and replace it with little trouble. The only issue I have now is that there is not much water coming out of the "pee" hole. I am assuming there are bits of impeller stuck in the water passages. Does any one have any suggestions on how to clear those passages out? When I had the lower unit off I ran a clothes hanger up the tube heading up to the motor. Is there anything other than compressed air that I can use on the other passages?

Thanks.
 

Tex Red

Recruit
Joined
Jun 14, 2010
Messages
5
Re: Mercury 9.8 stuck in forward gear

It PEES!!! I took a good air nozzle and blew air up backwards through the pee hole. It bubbled really good in my test barrel when I did that and when I started it up it starting peeing right away. I ran it for a bit - in gear and out of gear. I then stopped it, let it set, and tried it again. I did that process three times and each and every time it peed great.

This has been a great learning process. I know a lot more about my engine now - which is always a good thing.
 
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