I think my forward gear has worn out

johnshera

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I took my 1976 135hp cheetah for a spin and everything was going well for awhile so I thought. I had it in the Missisippi river going with the current. I slowed down and put it on neutral so I could strap some things down before they flew but when I went to to put it in gear it made a clunk clunk sound along with several jerking motions and then it took off fine. I then turn it around against the current to start riding back because I knew something wasn't right but I did something so dumb, I decided to stop and put it back on neutral and this is when all hell broke loose. It wouldn't go back on gear, the current was moving like 7-10 mph and the boat was getting further and further away. Just to check I put it on reverse and it worked. I then put the trolling motor to work but the current was too strong by then I was about 3 miles away from my truck. So I put it back on reverse and turned the boat around and finally I started to get closer. Do you know how hard that was to drive the boat on reverse against the current? Man that was scarey! It seems my forward gear are shot doesn't it? Do anyone agree with me or could it be the something else?Clutch dog? This might seemed like a dumb question but If so, can I replace the gears without taking off the whole lower unit?
 

Joe Reeves

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Re: I think my forward gear has worn out

Before you start taking that lower unit apart, check the shift cable at both the engine and at the control box to make sure that it hasn't come out of the clamping areas.

Also.... you might want to remove the shift cable from the engine clamping area momentarily, then try shifting into gear using the engine shifting linkage alone.
 

johnshera

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Re: I think my forward gear has worn out

Sorry it took so long to get back at you.


Ok, I checked the cable and it seemed to be ok. (out of the water) I can shift the motor in forward and the propeller spins with no out of the ordinary sounds or problem. Question though, if it is out the water it will a spin anyway because it doesn't have any lbs and pressure to work with? Or am I wrong or is there something else making my forward not engage?
 

tashasdaddy

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Re: I think my forward gear has worn out

could have a spun prop. take a permanet market and draw a line across the complete hub. put it in the water try taking it for a spin.. if the marks are still line up it's not the prop. the prop has the inner and outer metal hub with a compressed rubber hub between, these can fail and cause the prop to slip.
 

ezeke

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Re: I think my forward gear has worn out

Sounds like the prop to me as well.
 

Silvertip

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Re: I think my forward gear has worn out

But it worked ok in reverse! If you shifted into forward and the prop spins freely something is wrong. Disconnect the cable as Joe suggested and then shift manually into forward. If the prop still spins freely, something is broken.
 

johnshera

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Re: I think my forward gear has worn out

Ok , Like Silvertip have mention, the propeller work fine in reverse, it saved my day! I shifted into forward and the propeller spin at command. When I shift it into forward without giving it any extra gas it still turns just a little(very slowly) but I'm thinking its because its out the Water.

I would hate to put it back in the water, It would be so much of a hassel. I live not too far from the Mississippi River and putting it in the river would be a mistake (current too strong), the next destination would be about an hour drive just to put the boat in the water and embarass myself when it starts acting up again. Putting the boat back on the trailor without forward progress is no easy task.

Is there a sure way to find the slip on either on the gear or the propeller?
 

Silvertip

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Re: I think my forward gear has worn out

It makes no difference if the engine is in the water or not. Why don't you do the test both Joe and I have recommended and prove once and for all what the problem is. Disconnect the shift cable at the engine. Now move the shift lever (the one on the engine) into forward. If you can turn the prop by hand the lower unit is damaged. If not, it is shifting fine and the cable needs adjustment or the control box has become worn and cannot engage forward gear.
 

johnshera

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Re: I think my forward gear has worn out

Silvertip, I must be misunderstanding you. I've shifted the gear in forward and it spins. Are you saying to shift the lever by hand to see if I'm able to put it into gear and if I'm able to do it by hand that would mean something is wrong with the in the lower unit.. I will do it as soon as possible. Right now I have like 20 million other things to do right now. I will post again once I have done of what was asked.

Not to be funny but :$ lol you go back and read what you wrote you're making it sound like you want me to stick my hand on the prop while in gear and try turning it. I love my hand, man I don't want it cut off.d:) lol
 

Joe Reeves

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Re: I think my forward gear has worn out

John..... We're speaking of disconnecting the shift cable, then shifting with the engine NOT RUNNING.

Out of the water, running on a flushette, the propeller will spin simply due to internal friction.
 

johnshera

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Re: I think my forward gear has worn out

Oh, that's a big misunderstanding, My bad, guys! Thanks Joe for clearing that up for me. Now it is making more sense to me. I will do it sometime today if it don't rain.

For the younger guys out there always do this after you disconnect the battery!
 

Silvertip

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Re: I think my forward gear has worn out

John -- I can't believe you would even think I wanted you to stick your hand on a prop -- on a running engine -- in gear -- in the water or out. :| Let this be a lesson to anyone offering assistance -- never overestimate the ability of the person you are trying to help. I once read a story where a guy lost all his fingers trying to use a rotary lawn mower as a hedge trimmer. But then many years ago in the middle of a Minnesota blizzard I entered a Sears Surplus store as a guy of middle east decent was pushing a new rotary mower through the snow to his car. I made a smart a$$ remark about the mower and the guy was flabergasted. He thought he had bought a snowblower.
 

johnshera

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Re: I think my forward gear has worn out

Update: I took the cable off , put it in forward gear and it did not turn unless I forcefully turn the propeller abling to hear compression. Does this help ?

Question though, Is it normal for a propeller to have slack in gear. For example when I turn it clockwise it engages but I'm still able to turn it countercolckwise about inch(slack), is the normal?
 

ezeke

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Re: I think my forward gear has worn out

Take the propeller off and look at the black rubber grommet in between the two parts of the propeller's hub.

You have to take the thrust bushing off and look at it from the rear.

Tell us what you see.

As others have said, the shift cable on your motor can slip in the casing guides when you are moving to forward gear because it is pulling. The cable may also be broken.
 

johnshera

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Re: I think my forward gear has worn out

Nevermind its not the propeller with the slack its the propeller shaft that holds the propeller. Is that supposed to have a little slack?
 

Joe Reeves

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Re: I think my forward gear has worn out

John..... I think that it's possible that you are not fully understanding what we're trying to get across to you.

The reason for removing the cable and shifting by hand is to verify (or not) that the engine is actually going into gear.

The fact that the shifter dog is engaging the gear (I assume you're shifting into forward gear) and you can force the engine to turn over by turning the propeller proves that the unit is shifting into gear.

If by re-connecting the cable and repeating the shift sequence, the unit either goes into gear or does not, would prove that something is wrong with the control box or cable... or not.

Now, another method to checking the propeller hub for slippage is to have the engine in gear and block the prop from turning with a 2x4 or a piece of wood of your choosing. Then, with the proper socket and long breaker bar, apply turning pressure to the flywheel but in a clockwise direction..... a great amount of pressure.

If you can turn the engine over, having the propshaft turn within the propeller (the prop can't move, it's blocked), the hub is obviously slipping and the propeller will require re-hubbing or replacing.

Now, assuming that after you check the propeller for slippage either by this method or by the marking method of "Tashasdaddy's" post (as above), you find that the propeller is okay..... and nobody has changed, moved, repaired, added anything, adjusted etc.... and as I mentioned in this reply (control box and cable check) you find these two items to be okay, check the gear lube for metal filings, chips, fairly big pieces.
 

johnshera

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Re: I think my forward gear has worn out

ezeke said:
Take the propeller off and look at the black rubber grommet in between the two parts of the propeller's hub.

You have to take the thrust bushing off and look at it from the rear.

Tell us what you see.

As others have said, the shift cable on your motor can slip in the casing guides when you are moving to forward gear because it is pulling. The cable may also be broken.


The rubber looks like new and the gears in the propeller also decent (no grind)

I will start investigating on the throttle case right now.
 

johnshera

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Re: I think my forward gear has worn out

Joe ... I will do the slipage check like you asked.
 

johnshera

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Re: I think my forward gear has worn out

Joe... I've marked the propeller with white touch up paint and placed it back on the shaft, tighten it down, place a block of 2x4 to keep the propeller from turning, place the 1 1/4 socket on it and turned it clockwise. I weigh about 253 lbs and I applied about that much (sort of speak)to the turn. When I took it off and looked at the marks it had moved a little less than 1/16th of an inch. Does this explain anything? It was alot of pressure on that propeller. I can't imagine the water making the propeller slip after that but I could be wrong! What you think?
 

ezeke

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Re: I think my forward gear has worn out

Are you saying you put that pressure on the flywheel?

Joe Reeves said "....apply turning pressure to the flywheel but in a clockwise direction..... a great amount of pressure."

Turning it from the propeller nut would probably show a badly spun prop anyway, but you don't have the heat from the exhaust in either approach.

At this point, it is beginning to read like the propeller is not the problem.
 
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