Johnson 9.9 hp lower unit question

[pecheux]

Good day y'all, (lol)

This jewel to me 1981 low hours & mint condition OB has never had a drop of water in the LU. OIl drained each year still looked like new. But last summer I hit bottom real hard and solid (rock), and part of the fin broke. LU oil change after that showed the grey milky mix that means water in oil. Motor stored vertical for winter and I cannot see any oil dripping anywhere. Question: What should I suspect to be the problem ? Will have it fix for sure but it would be nice to know what to expect.

Thank you and best wishes for coming Xmass & New year holidays.

 

[boobie]

Re: Johnson 9.9 hp lower unit question

Take it to a shop and have it pressure and vacuum checked. That way there's no guess work.

 

[izoomie]

Re: Johnson 9.9 hp lower unit question

Did you bust up the prop too, or just the skag?

I've run old johnsons for years and mine all had water in the lower unit issues. For the worse one, I would change the lower unit oil twice a year, for the others I only did it once a year. Always leave it with fresh clean oil before the winter. They all worked fine for me. 10hp, 50hp and 90hp. You can run like that a bit but if you want to avoid the worry, then eventually get it tested. They will tell you exactly where it needs work.

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

cancelled

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

Take it to a shop and have it pressure and vacuum checked. That way there's no guess work.

Sounds like a plan, thank you for your advice

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

Did you bust up the prop too, or just the skag?

I've run old johnsons for years and mine all had water in the lower unit issues. For the worse one, I would change the lower unit oil twice a year, for the others I only did it once a year. Always leave it with fresh clean oil before the winter. They all worked fine for me. 10hp, 50hp and 90hp. You can run like that a bit but if you want to avoid the worry, then eventually get it tested. They will tell you exactly where it needs work.

Prop got nagged along the edges, but I can fix that. Well my favorite fishing spots are 5 miles away on the river, plus my wife enjoys the ride. Got a fin on it that allows to run on the step at good speed. so I'll have it fixed. loll

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

Take it to a shop and have it pressure and vacuum checked. That way there's no guess work.

I dont know how many seals there are in such a LU. OB mecanic not available until 2 weeks from now (winter here) What should I expect for ball park cost $ to replace all LU seals ? Tx

 

[Putzaroni1]

Re: Johnson 9.9 hp lower unit question

I dont know how many seals there are in such a LU. OB mecanic not available until 2 weeks from now (winter here) What should I expect for ball park cost $ to replace all LU seals ? Tx

I believe there is one seal on the top of the lower unit and 2 in the bottom where the prop shaft comes out. The one is to keep the oil in and the 2nd is to keep the water out. Take the above advice and get it pressure tested. That will tell you exactly where it's leaking out and you will then know what needs to be done to address any leak.

Also, you might want to consider a River Runner if you're running the river in a prop boat.
Mac's Prop Savers, Inc - Go Where no Prop Has Dared!

They take a small amount of the top end off but will save your bacon on the river if you do hit something.
If you install one of these you won't need to repair your skeg as it covers over it.

Just my 2 cents.

 

[racerone]

Re: Johnson 9.9 hp lower unit question

Two seals under the water pump.---O-ring on the shift rod.---Two seals on the propshaft.----O-ring on propshaft bearing carrier and the wee nylon washers on drain / fill screws.

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

Two seals under the water pump.---O-ring on the shift rod.---Two seals on the propshaft.----O-ring on propshaft bearing carrier and the wee nylon washers on drain / fill screws.

Thank you for the details. Can anyone give me an idea of what to expect in term of $$$ cost ... installed ?

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

I believe there is one seal on the top of the lower unit and 2 in the bottom where the prop shaft comes out. The one is to keep the oil in and the 2nd is to keep the water out. Take the above advice and get it pressure tested. That will tell you exactly where it's leaking out and you will then know what needs to be done to address any leak.

Also, you might want to consider a River Runner if you're running the river in a prop boat.
Mac's Prop Savers, Inc - Go Where no Prop Has Dared!

They take a small amount of the top end off but will save your bacon on the river if you do hit something.
If you install one of these you won't need to repair your skeg as it covers over it.

Just my 2 cents.

Thank you for your suggestion. River runner = nice but approx same cost as having the skeg rebuit thus no loss of wot speed, which is borderline with a 9.9 on a 14 footer fiber. Had a bent skeg on a 115 hp and this one with a partly broken skeg on a 9.9 in half a century of river boating. Not a bad average ... LOll Cheers

 

[oldboat1]

Re: Johnson 9.9 hp lower unit question

might keep an eye out for a used replacement unit, which you might be able to use as is or use for parts (or reseal and use). It sounds like your fishing grounds are a little tough on lower units....

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

Spoke with my OB mecanic on the phone today about LU taking water. He suggest I first start to check if prop shaft is warped. He says to take the prop off and turn shaft with a tool to proceed. Says if shaft is warped no seal will stay put, and we are looking at a different problem. Shall check as soon as weather get above -25 C and I dare take my vehicule out of the heated garage ... LOLL

 

[rolmops]

Re: Johnson 9.9 hp lower unit question

Spoke with my OB mecanic on the phone today about LU taking water. He suggest I first start to check if prop shaft is warped. He says to take the prop off and turn shaft with a tool to proceed. Says if shaft is warped no seal will stay put, and we are looking at a different problem. Shall check as soon as weather get above -25 C and I dare take my vehicule out of the heated garage ... LOLL

That sounds like a no nonsense mechanic. By all means,follow his advice but put a straight piece of pipe (plastic ,pvc,whatever) about 3 feet (1 meter) long on the shaft. That will exaggerate any warping and make it easier to see.
My suggestion is completely different. Maybe the the seals on the oil change holes were not completely tight and there is nothing wrong . Maybe that is why it is not leaking now. I would run it in a barrel for half an hour or so and check the oil again.
Bonne Chance.

 

[oldboat1]

Re: Johnson 9.9 hp lower unit question

like rolmop's idea. See what you have first by test running it. I still recommend another unit if yours is too banged up to make repair worth it. Maybe a motor with a blown powerhead.

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

That sounds like a no nonsense mechanic. By all means,follow his advice but put a straight piece of pipe (plastic ,pvc,whatever) about 3 feet (1 meter) long on the shaft. That will exaggerate any warping and make it easier to see.
My suggestion is completely different. Maybe the the seals on the oil change holes were not completely tight and there is nothing wrong . Maybe that is why it is not leaking now. I would run it in a barrel for half an hour or so and check the oil again.
Bonne Chance.

Thanks for your feedback. I like the idea of running it in a barrel and check the oil again. On the other hand I have no positive expectation since I did hit a rock at WOT on the step and as you can see by the pic it broke the skeg. Hit so hard the motor cover came off ... But will have to wait until it's warmer so I can run it with garage door open. Still -22 C here ... LOL

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

like rolmop's idea. See what you have first by test running it. I still recommend another unit if yours is too banged up to make repair worth it. Maybe a motor with a blown powerhead.

That would be my first choice ... but very hard to find a used LU at reasonable cost here up north. Tx

 

[racerone]

Re: Johnson 9.9 hp lower unit question

You have to know where and how to shop.--------Found a complete 9.9 HP ( as is where is ) with the same L/U as yours at a dealer doing clean-up.-$30.00 and put it into my truck

 

[rolmops]

Re: Johnson 9.9 hp lower unit question

I just looked at the picture again and it is my feeling that unless the outboard was locked in position it jumped up and probably out of the water and there was probably minimal damage. I mean,it's a 9.9 not a fifty horse and even when on plane you probably were doing well under 20 kph. This low speed and the outboard jumping up and on top of that the outboard still running fine tells me that you probably did hit that rock with the lower part of your skeg,and the picture shows as much. You should fix the skeg so it can properly protect the propeller. That is probably all you need to do.
Can you please PM me to tell me whether I was right or wrong?
Rolmops

 

[pecheux]

Re: Johnson 9.9 hp lower unit question

You have to know where and how to shop.--------Found a complete 9.9 HP ( as is where is ) with the same L/U as yours at a dealer doing clean-up.-$30.00 and put it into my truck

Wish I could find such a deal. Scarce in my neck of the wood.