Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

bcollins47

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We were on the lake on last weekend and going along smoothly. Than we heard a noise and now the boat won't go in gear. Acts like it is in neutral. If you put it in reverse the engine dies. Any idea what could have happened?


Thanks for your help!
 

ktbarrentine

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Greetings and welcome. If you search the threads on this forum, you'll find numerous ones similar to yours. Can you provide more info on the symptoms, like what kind of noise, did you smell anything, did your water temp go up after the event? Sounds like it could be: Blown engine coupler (symptom is smell of burnt rubber in engine compt. and an increase in engine water temp due to lack of cooling water from the outdrive), bad coupling splines (might see metal flakes around the coupling area in the engine compt, same symptom with the water temp), broken U-joint(s), stripped upper gears in the outdrive, Broken vertical shaft in the outdrive, spun prop hub, etc. Shift cable bad or out of adjustment can result in the symptom of engine dying when shifting to reverse. Have you got it out of the water so you can do some diagnostics and dissassembly/inspection?
 

tpenfield

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

We were on the lake on last weekend and going along smoothly. Than we heard a noise and now the boat won't go in gear. Acts like it is in neutral. If you put it in reverse the engine dies. Any idea what could have happened?


Thanks for your help!

A noise ??? do you have any idea of what kind of noise and could you describe it? Something may have broke . . . could be in the lower unit, but a bit more info would be helpful.
 

Bondo

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

We were on the lake on last weekend and going along smoothly. Than we heard a noise and now the boat won't go in gear. Acts like it is in neutral. If you put it in reverse the engine dies. Any idea what could have happened?


Thanks for your help!

Ayuh,... Welcome Aboard,... What drive,..??
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

We were going about 20 miles an hour when we heard a sound like a bolt breaking. Than nothing ..... Usually you can feel when the boat goes in gear. Now you can't feel anything when you put it in forward gear. When you put it in reverse it dies. Haven't had a chance to look at the boat yet. I was hopefully for a little guidance on were to start looking.

Were you would suggest I start???


Thanks for sharing your knowledge!
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

We were going about 20 miles an hour when we heard a sound like a bolt breaking. Than nothing ..... Usually you can feel when the boat goes in gear. Now you can't feel anything when you put it in forward gear. When you put it in reverse it dies. Haven't had a chance to look at the boat yet. I was hopefully for a little guidance on were to start looking.

Didn't notice a change in water temperature but I didn't run it very long.
No smell that I noticed but I didn't check at the time.


Were you would suggest I start???


Thanks for sharing your knowledge!
 

ktbarrentine

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

I suggest you start (with boat out of water), with engine OFF, put shifter in fwd and try to turn prop in both directions. Should "lock" CCW and should "ratchet" CW. If you are able to turn the prop (with some resistance) CCW, then you are disconnected from the engine, i.e. broken shaft or bad splines or stripped gears. Then do same after shifting to reverse, except should lock CW and ratchet CCW. Tell us what reponse you get. The next step is to pull the outdrive and get a little more intrusive to check for the coupler or gears or shaft issues. The shifter check is simple and quick, but is a bit limited in what it can tell you. KTB

Sounds to me (IMHO) that you are into pulling drive, possibly followed by draining drive oil and splitting the drive apart depending on what you find after first pulling the drive off the boat.

Have you done a "good" look in the engine compartment at the coupler to see if there is a "smoking gun" there? (bits of rubber, black dust, obvious damage)
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

I suggest you start (with boat out of water), with engine OFF, put shifter in fwd and try to turn prop in both directions. Should "lock" CCW and should "ratchet" CW. If you are able to turn the prop (with some resistance) CCW, then you are disconnected from the engine, i.e. broken shaft or bad splines or stripped gears. Then do same after shifting to reverse, except should lock CW and ratchet CCW. Tell us what reponse you get. The next step is to pull the outdrive and get a little more intrusive to check for the coupler or gears or shaft issues. The shifter check is simple and quick, but is a bit limited in what it can tell you. KTB

Sounds to me (IMHO) that you are into pulling drive, possibly followed by draining drive oil and splitting the drive apart depending on what you find after first pulling the drive off the boat.

Have you done a "good" look in the engine compartment at the coupler to see if there is a "smoking gun" there? (bits of rubber, black dust, obvious damage)



Thanks.... I will try it tonight and let you know what I find....
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

So I ran the check on the Boat and confirmmed what ktbarrentine suspected that the we were disconnected from the engine. I could turn the prop ccw on fwd and cw on reverse. It did rachet on forward and reverse . I'm assuming I should pulle the the drive at this point . Correct?

... No smoking gun.... no bits of rubber or black dust in the engine compartment.
 

ktbarrentine

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Yep...time to pull the O/D and have a look-see. One thing you could do first is pull the top cap off of the upper and see the condition of the upper gears. Just costs a gasket to look. Post pictures, if you can. Oh, and drain the O/D oil into a clear container and check for condition of oil (water, bits of metal, etc., or just good, stinky-smelly O/D oil).
 

BF

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

have you drained the outdrive oil? That's the first thing I'd do... water/metal filings/chunks of gear in the oil? Also, before pulling the outdrive you could inspect the shift cable and make sure it is moving enough to fully engage into fwd. The stalling when going into reverse really points to the lower unit though. Remember that everything from the engine up to, but not including the clutch dog/propshaft is being turned whenever the engine is running, whether it is in F, N or R. If engine runs normally in "N" then I'd say your U-joints & uppers are probably OK, your lower unit drive shaft is either OK or completely sheared, and your fwd gear in the lower unit is probably OK (since it turns at all times too, even in "N" just clutch dog does not engage in it. Again, look for metal in oil, and see if the lower unit oil has had water intrusion.
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

have you drained the outdrive oil? That's the first thing I'd do... water/metal filings/chunks of gear in the oil? Also, before pulling the outdrive you could inspect the shift cable and make sure it is moving enough to fully engage into fwd. The stalling when going into reverse really points to the lower unit though. Remember that everything from the engine up to, but not including the clutch dog/propshaft is being turned whenever the engine is running, whether it is in F, N or R. If engine runs normally in "N" then I'd say your U-joints & uppers are probably OK, your lower unit drive shaft is either OK or completely sheared, and your fwd gear in the lower unit is probably OK (since it turns at all times too, even in "N" just clutch dog does not engage in it. Again, look for metal in oil, and see if the lower unit oil has had water intrusion.


I will drain the oil tonight.... What is puzzling to me is what caused the problem in the first place. We have only owned the boat for a month but have used it several time without any issues. Is there a weak link in these units? Is there somthing I could have done to prevent this issue?
 

series60

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Is there a weak link in these units? Is there something I could have done to prevent this issue?

For the most part there aren't weak links in these outdrives. The weak link is the PO lack of proper maintenance! Engine alignment is one of the most critical adjustments on these outdrives.

FYI: If you have to change the engine coupler you will need to pull the engine. First pull the outdrive and look inside the cavity with a flashlight and see how the splines look on the coupler. The first picture is what you should see with the outdrive off.

This second picture should give you some idea of how the coupler splines should look. This coupler was still running but the splines are very worn. They were starting to develop very sharp edges and a few had some chipping stating.
 

BF

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Did you check the lower unit oil when you bought the boat? (to see that 1- it was full and 2- that it looked good with no water) Did you check the lower unit oil again after using the boat to see if there was any water intrusion? Those are things that I always do when running a new-to-me boat. If a lower unit seal was bad and allowed water intrusion, you will get bearing failure at some point. How long that would take likely depends on how much oil has been displaced by water. An un-scupulous seller can hide a leaky lower unit by putting new oil in just before the sale. Who's to say if the seal was bad before, or failed during your first few outings?

How's the prop look? Any chance you hit a submerged log?
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

I changed the drive Oil when I bought the boat. Looked ok at that point. The prop was a little chewed up when I bought it. Thought they may have hit a rock or something at some point. Probably did enough to weaken it. Plan to pull it off tonight so I will let you know what I find... Thanks again for your help!
 

ktbarrentine

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

For the most part there aren't weak links in these outdrives. The weak link is the PO lack of proper maintenance! Engine alignment is one of the most critical adjustments on these outdrives.

FYI: If you have to change the engine coupler you will need to pull the engine. First pull the outdrive and look inside the cavity with a flashlight and see how the splines look on the coupler. The first picture is what you should see with the outdrive off.


This second picture should give you some idea of how the coupler splines should look. This coupler was still running but the splines are very worn. They were starting to develop very sharp edges and a few had some chipping stating.

Your links dont seem to work.
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Your links dont seem to work.



So drive gear.jpgI found the problem..... I pulled off the top cover of the down drive and found both gears destroyed. Checked the coupler and everything else appears to be fine. Question is how can i take apart the middle section and replace the gears? The gears appear to be hooked to the shaft. Would my local boat shop have these parts? Does anyone have access to the manual for a Merccurizer Alpha 1 downdrive? Any advise on how to take this unit apart?

See photo of the side gear.... other gear looks the same.

Read another post with the same issue.... Sounds like I should buy a replacement....

My serial # on the drive is 0D569813 ..... What is the replacment part I would need?

Thanks
 

ktbarrentine

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Man...so sorry... looks terrible! Have you drained your oil? What did you find? If you have traces of metal in the oil coming out of the lower, you're probably looking at a new drive. The metal from the gears in the upper migrates to the lower.

Look in the "adults only" sticky at the top of this forum for the information on your drive. Find the section called "mercruiser information" and in that, find the section on "service manuals"...

Taking it apart is not difficult...it is the rebuilding that is a challenge, and takes special tools and such...and if you have metal in the oil, may not be worth that effort or cost.
 

bcollins47

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Re: Boat made noise and now acts like it is in neutral. 91 searay 4.3 in/out board

Man...so sorry... looks terrible! Have you drained your oil? What did you find? If you have traces of metal in the oil coming out of the lower, you're probably looking at a new drive. The metal from the gears in the upper migrates to the lower.

Look in the "adults only" sticky at the top of this forum for the information on your drive. Find the section called "mercruiser information" and in that, find the section on "service manuals"...

Taking it apart is not difficult...it is the rebuilding that is a challenge, and takes special tools and such...and if you have metal in the oil, may not be worth that effort or cost.


Real small flakes of metal in the oil.... Do you think I can get away with just replacing the upper section or do you think I would replace the whole thing?
 
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