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Mercury 110 9.8 HP No spark on top cylinder

forward gear the propshaft should ratchet in one direction you must turn the driveshaft or propshaft in order to shift into reverse to line up the clutch dog. Without the water pump on the driveshaft should spin real easy just pour some gearoil down the hole and see if it loosens up. What condition was the oil in the gearbox? If the driveshaft is pitted down where the lower seal rides in the water pump you may be able to speedisleeve it without pulling the driveshaft. Either way it needs to be fixed.
 
Gotcha on the shifting. I just drained the gear oil and it was mostly water and some brown goo. I'm guessing water can infiltrate at the o-ring on the bottom of the water pump. It feels to me like it has a bad bearing so I guess the driveshaft is going to have to come out. Rats! I was hoping for an easy fix. The shaft was def pitted above the impeller as I had to sand it pretty good before the water pump stuff would slide off. I'll take a close look at it once it's out. Thanks again for the help it is much appreciated.
 
A little info on me. I am a carpenter and have been slow lately so I have been getting into buying and selling equipment and such. I buy stuff for next to nothing at local auctions, repair and flip. Started with chainsaws but have tried other things. More often than not I get lucky and the stuff either works fine or only needs a few hours of repair. Once in awhile I get something like this that presents more of a problem. Things take awhile when you have to figure out what your looking at in the first place. Something like this I will keep because I get attached to the machine after spending so many hours on it.
 
I had a touch of insanity a few years back and just started buying older mercs on craigslist and been through a bunch of gearboxes 4hp - 9.8hp. You need the cover nut special tool to remove the carrier for the propshaft. If you do get it apart pay close attention to the shims they are paper thin and easy to damage or misplace. Parts are expensive if you can even find them the seals can be a challenge. The cover nut for the bearing carrier is left hand thread and do not use a hammer any where on the gearbox. You have to pull the prop to get the pinion nut off to remove the driveshaft and upper bearing. I only got lucky once and found a good gearbox with a blown powerhead usually the gearbox will condemn the motor. I might be convinced to sell my gearbox tool for the cover nut if your interested.
http://store.oldmercs.com/product_p/91-99222t.htm
same as this one
 
Well I got the shaft out and everything apart. CT boat repair in South Windsor CT had a cover nut tool that was close enough to work. Even gave it to me. For some reason when I removed the retainer everything loosened up. Pulled the driveshaft and everything was A OK except the pitting on the shaft where the water pump rides like kimcrwbr said. See pics. It is enough to catch a nail on the bottom. IDK, There's a couple on ebay but one match is worse than mine and the few others are $100plus. I looked up speedisleevemerc110shaft.jpg and that could work. Or I am thinking maybe a thin coat of fiberglass resin or good bondo sanded back to fill pits. Whatya think?
 
Did you find any shims where the bearing carrier fits in tight to the gearbox. Sounds like it has been taken apart recently if it was that easy to pull the carrier out. Those shims are real easy to miss or damage real thin and not very wide. They are for gearlash for the reverse gear there are shims under the bearing race for forward gear bearing and then shims for pinion height on the upper driveshaft bearing. Gearlash for the forward gear is easy to check without the seals or impeller in the water pump tighten it down and lift up on the driveshaft and wiggle the propshaft you should feel the lash. For reverse lash you need to push the high spots between the reverse gear and clutch dog together with the shift lever nad wiggle the driveshaft you should feel backlash.
 
Yes there was one shim betwixt the carrier and housing. Good to know what those shims are for. I ended up using pc-7 on the shaft. Whether or not it will hold up is to be determined.
 
kimcrwbr1 said:
http://www.ebay.com/itm/Mercury-Powerhead-Engine-Block-9-8-hp-105-108-psi-Comet-Lightning-7-5-1973-/151816550864?hash=item2358f8b9d0:g:6YcAAOSwv0tVX12~&vxp=mtr
Look on the top of the powerhead is a 90 degree elbow with a barbed nipple. Get a 1/8 inch fitting with a drill and tap and add the port on top of the water jacket. I just use a drill coated in grease to catch the shavings wipe it and coat it with grease then do the same with the tap you just need a few threads to hold the fitting on tight and then use loctite after cleaning it good. Drill a hole in the lower engine cover to run a tube through and put a restrictor on the end. I have used a regular teltale fitting before also.
http://www.ebay.com/itm/USED-MERCUR...ash=item419ec69f30:g:eqgAAOSwT5tWKjzk&vxp=mtr
Click to expand...
Top of the water jacket is a little vague for me. Can you somehow be more specific? I noticed this plug screw in the pic. Is that area what you mean? Thanks again...Joelwater.jpg
 
Is the hole threaded? If you go to thread the hole just thread it deep enough to get about 5 threads until the fitting get nice and tight. Dip the tap in bearing grease to catch the shavings. Tap it slow keep the tap clean and full of grease.
 
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