1971 50 HP Jumping Out of Forward Gear

ARayT

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Apr 30, 2009
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19
I'm having a problem w/ my motor it feels like its jumping out of forward gear at about 1/4 throttle. I tore into my lower end last night expecting to find the clutch dog and gear worn. It does show wear but I'm not sure this is totally my problem. I had a similar problem last year w/ it not going into forward. This ended up being a stuck shift piston. Now it shifts Ok but will jump out at about ? throttle. Could it be an adjustment problem w/ the solenoids with the plunger not totally being removed from the ball ports? Or does this sound like the clutch dog/ gears are worn? Attached are pictures of the clutch dog and gear. Can the clutch dog be rotated? I would appreciate any advice.
Thanks Again Ray
 

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dew2

Senior Chief Petty Officer
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674
Re: 1971 50 HP Jumping Out of Forward Gear

I looked at the clutch dog first I thought it was iffy,Then the gear its had it,Need to replace both.Or get a used lower,problem there it may be just as bad. I get some great deals on these gears from ebay.It takes time to find the correct dog and gear but I take my time.If your in a hurry ??
 

boobie

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Re: 1971 50 HP Jumping Out of Forward Gear

Gear and dog are definately bad.
 

ARayT

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Re: 1971 50 HP Jumping Out of Forward Gear

Gear and dog are definately bad.
Can the clutch dog be turned around? And on top of the top soleniod there's a rubber washer about 1/8" thick thats in real bad shape, cannot find a part number for it to replace, is this critical? When I adjust the solenoid plunger should I go from the top of this gasket of from the top of the soleniod?
Thanks Ray
 

Joe Reeves

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Feb 24, 2002
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Re: 1971 50 HP Jumping Out of Forward Gear

In total agreement with "Boobie". That forward gear and shifter dog lobes are worn as bad as any I've ever come across. The shifter dog cannot be reversed.... notice the imbedded print on one end that states "Prop End". Even if it were possible to reverse the shifter dog, it wouldn't last any time at all with that worn forward gear.

The rubber washer you speak of is a Mickey Mouse patch job. That's supposed to be a wave washer with the part number of 314126, about $7.00. If you can't find one, I have one left in my remaining stock. This wave washer missing could have led to your current problem. Also that lower unit demands a special gearlube... Premium Blend, also known as Type C, available at your dealership and possibly Sierra..... you cannot use HiVis gearlube which is used in the standard shift models.

Solenoid plungers are adjusted "in the gearcase".....no lower than 1/64" from the top of the solenoid.
 

ARayT

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Re: 1971 50 HP Jumping Out of Forward Gear

Thanks Joe,
I have a new forward gear ordered. Can the face of these be dressed up? I do have the wave washer but on top of the soleniod it has a rubber washer or it could be part of soleniod itself. Its partially stuck.
Thanks!!
 

boobie

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Re: 1971 50 HP Jumping Out of Forward Gear

Did you order a new dog also ? If you didn't your wasteing your time. A SUPER machine shop could probably re-cut the gear and dog but what would it cost to get it all symmetrical ??
 

ARayT

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Re: 1971 50 HP Jumping Out of Forward Gear

I have not but I will. Thanks for the advice!!
rt
 

Joe Reeves

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Re: 1971 50 HP Jumping Out of Forward Gear

The wave washer is the only item to be sitting upon the top solenoid... No rubber washer! Inspect that solenoid carefully for flaws.
 

dew2

Senior Chief Petty Officer
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May 6, 2010
Messages
674
Re: 1971 50 HP Jumping Out of Forward Gear

I have taken gears and dogs to the 4 area machine shops near me,All said it would cost more than buying new.They did quote prices.With set up and having to mate the two surfaces they were 75 to 100 more than new.Hard to believe,but they were all close to the same quote.
Mine was from a 25HP with two ears on the dog and gear,EARS or whatever they would be called.
 

F_R

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Re: 1971 50 HP Jumping Out of Forward Gear

Anyhow, those parts are hardened and heat treated. Once the surface is worn/ground away, so is the hardness. They may last long enough after regrinding to unload the motor on some sucker, but that's about it.
 

ARayT

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Re: 1971 50 HP Jumping Out of Forward Gear

Anyhow, those parts are hardened and heat treated. Once the surface is worn/ground away, so is the hardness. They may last long enough after regrinding to unload the motor on some sucker, but that's about it.

Many Thanks!!! I'll get both, get it right and then I plan on selling her. Really appreciate the site and the advise from all. I don't mind working on things and it sure helps getting advise from the experts.
Ray
 

jbjennings

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Jul 18, 2007
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3,903
Re: 1971 50 HP Jumping Out of Forward Gear

I find it really strange that the model mentioned would have dog and gear ear wear. I would have thought that the hydroelectric lower unit would be relatively immune to such problems by design. I wonder if there's another problem, too. Maybe too high of an idle setting and therefore high rev shifting?
Just curious,
JBJ
 

ARayT

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Re: 1971 50 HP Jumping Out of Forward Gear

I find it really strange that the model mentioned would have dog and gear ear wear. I would have thought that the hydroelectric lower unit would be relatively immune to such problems by design. I wonder if there's another problem, too. Maybe too high of an idle setting and therefore high rev shifting?
Just curious,
JBJ

Well BJ to be honest your on track. I had problems w/ this thing several weeks ago, took an old buddy fisking or at lease wanted to and the darn thing would no go. This was after running it on muffs at home. I made several attempts I repeat several to get her to go, every time I shifted her into gear it would stall. I'm sure I'm responsible for the rounded edges on the dog and gears. The bad part about it is I took it to a shop and paid to have it repaired and still the same thing happened on my next trip. Again she would not run and started jumping out of gear too. So I plan on fixing the gear problem myself and then take it back to the person I paid to get it running. He diagosned the problem as being a sheered flywheel key.

I have one more question will a 317667 clutch dog fit this unit (1971 50hp 50172s)?
 
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