1997 Sears Gamefisher 9.9 2 stroke won’t start

[kmckoy]

I have a 1997 Sears Gamefisher 9.9 2 stroke that won’t start. It has a week spark ( hard to see the spark, but if I hold the plug it will tickle a little). The last time it ran it got really hot, I replaced the impeller since but I can’t get it to start again. Any help would be appreciated.

 

[pointblank1000]

I just recently sold a 1974 sears 7.5hp. I had to clean the carb since it was full of crud. Also this one had one of those extra tall impeller.
Was running great when I sold it.

 

[JDusza]

If there's a chance of overheating check compression first. You want to be sure your cylinder health is good before spending $$.
Spark should jump a 3/8" air gap. Spark on both?
Then manually add premix fuel into carburetor. You may have to pull a few times since manually adding fuel may initially flood the carburetor.
J

 

[kmckoy]

I checked compression the top cylinder is between 100-110 and the bottom is at 30. What should I do next?

 

[CaptnKingfisher]

I checked compression the top cylinder is between 100-110 and the bottom is at 30. What should I do next?

Sell it for parts. Unless you feel like pulling the head apart

 

[kmckoy]

I took the head off and the gasket was messed up for the bottom cylinder. There was some oil in that cylinder also, bu everything else looked good to me (same as the top cylinder smooth walls, a little carbon fouling). Can I use a build a gasket first to see if that fixes my not starting issues first before spending the money $20 on a real Mercury gasket ie. It shouldn’t mess anything up and it should work?

 

[CaptnKingfisher]

I took the head off and the gasket was messed up for the bottom cylinder. There was some oil in that cylinder also, bu everything else looked good to me (same as the top cylinder smooth walls, a little carbon fouling). Can I use a build a gasket first to see if that fixes my not starting issues first before spending the money $20 on a real Mercury gasket ie. It shouldn’t mess anything up and it should work?

Only if your willing to this all over again if it doesn't work. In my estimate my time has is worth more than $20, so I try not to risk cheaping on a job and potentially having to do it twice. Heard on car talk: "It's the cheapskate who pays the most in the end"

 

[kmckoy]

I ordered the gasket and need to get the gasket on and try it again. Hopefully tonight or tomorrow.

 

[kmckoy]

I put the new head gasket on and poured some gas directly into the cylinder and it fired like it wanted to start. I next tried to get gas in the carburetor but the fuel leaked out of the “compressor style “ fuel hose fittings. I assume these are leaking due to old orings, any recommendations for fixing them ore replacing them? The fitting on the engine threads onto the cowling so I am not sure if they could be replaced with something else?

 

[brim_buster]

what are compressor style hose fittings?

 

[CaptnKingfisher]

I put the new head gasket on and poured some gas directly into the cylinder and it fired like it wanted to start. I next tried to get gas in the carburetor but the fuel leaked out of the “compressor style “ fuel hose fittings. I assume these are leaking due to old orings, any recommendations for fixing them ore replacing them? The fitting on the engine threads onto the cowling so I am not sure if they could be replaced with something else?

I'd just replace the fitting never tried to disassemble one of those things. Did you do a compression test after changing the head gasket? Post your numbers

 

[kmckoy]

Compression was between 100-105 for the top cylinder and right on 100 for the bottom cylinder. Side note I bought a cheap Amazon compression tester for a different engine I am working on and got readings of 50 psi for both cylinders, I trust the first one more as I have used it previously.

 

[kmckoy]

Compressor style fittings are push connect fuel fittings just like a compressor hose and tool fittings

 

[brim_buster]

Bypass that crap run it straight to the carb with an in-line filter

 

[kmckoy]

I cleaned the fuel fittings and was able to get the bulb on the fuel line to get hard, but I was unable to get it to start. Compression is still good and the plugs smelled of fuel and I still have spark. I am going to replace the spark plugs and try again after that. Hopefully it will fire.

 

[CaptnKingfisher]

Did you ever address the weak spark issue? If it was my engine I'd go through this methodically. You've got good compression, now check spark. Use an adjustable spark tester so you can measure the strength of the spark. I don't usually see adjustable ones at my local autoparts store but Amazon will get ya one tomorrow. If you're not jumping 1/2" then you've got a problem in your ignition circuit. If spark is good then I'd verify idle mix is set according to your service manual. You can try pulling a spark plug and pouring a little fuel into the cylinder and cranking. If it almost starts or starts and stalls then you know you've got a fuel delivery issue. If this is the case, next try pouring a little fuel into the carb then cranking. If it does the same thing then you know the fuel issue is upstream of the carb and can start looking at the filter and fuel lines or at your tank for bad gas. If the pouring fuel into the cylinder works, but pouring fuel into the carb does not work then it's time for a carb rebuild.

 

[kmckoy]

Update on this. I got it running today. Had to clean the carbs, new fuel lines. The problem I have is it is not pumping water out the indicator. It seems like it isn’t pumping water through the engine at all as it gets warm after a few seconds running. The problem I had originally 10 plus years ago was I ran it and didn’t notice it wasn’t pumping water and got it too hot. I have taken the impeller out that I put in 10 plus years ago and it’s melted on the bottom where it runs against the stainless plate. The fund of the impeller look fine, so it should be pumping some water. I took it apart and blew air into the water line the impeller pumps to and air came out where the thermostat mounts, so it isn’t completely blocked inside.
Besides a new impeller what else should I be looking for?

 

[kmckoy]

I ordered a new impeller and a new impeller backing plate, the old one had some grooves in it.