1993 Johnson 48hp Clicking sound in Gearcase

I have a 1993 Johnson 48hp Outboard model J48ESLETE. We were at the lake and suddenly a clicking sound began coming from the engine. I put the engine in neutral and idled it up a little and there was no sound. I put it in reverse and still no sound. I then put it in forward and there was the sound. From what I can tell, it is not the engine and it only does it under load in forward gear. We were wuite a bit away from camp so we tried to make it but the clicking sound got worse so we shut off the engine and used the trolling motor to get back to camp. I got the boat on the trailor and out of the lake and then started the engine again. I put the engine in forward and no clicking so I am sure now it only does it when under load. I checked the gear oil before going to the lake and it was full. It was still full after this happened. I also checked the prop thinking maybe the shear pin come out or we were about to loose a prop and still found nothing wrong. I am pretty sure it is in the gearcase or maybe between the gearcase and engine but Im not sure yet what it may be. Does anyone have any ideas what I should look for or if there is something I have missed? I am hopeing to find it to be something simple but from the way it sounds Im pretty sure the gearcase is going to have to come apart. Thanks in advance for any help.

Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Just wandering if anyone has any ideas?

Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

I have continued checking for my problem and have not located any obvious signs of any issue except 1. I have found the gearcase oil to be black in color. Other than the color of the gearcase oil I do not see anything loose or broken. Any ideas?

Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Robert,

If you read the post I made earlier today it sounds very simular to the issue I had. The results of my neglect has now cost me a lower end unit. Lucky for me I located one for around $300.00. They are about $1500.00 for just a used one if you call the marina.

There are two gears (Forward and Reverse) and from your description of the problem you most likely have an issue with the forward gear. The book says to look for filings in the gear oil and to sample some of the oil at differant stages of draining and rub it between your finger and thumb to guage if any metals (sandy feeling) is present.

Just my opinion.

Andre

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Robert..... I'm familiar with Andre's disasterous lower unit blowup. The large slotted drain screw in the lower portion of your lower unit, remove it and drain the oil, looking for metal slivers, chips, chunks. If any are found, that lower unit needs to be dismantled for inspection.

Small fiber fuzzy like metal found on the drain screw magnet (even in what appears to be a large amount) is normal and is nothing to be concerned about, BUT the slivers, chips, chunks etc are.

Whether in gear or neutral, the pinion, forward, and reverse gear are turning constantly..... the noise is still there but one may not hear it distinctly unless under a load.

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Thanks. I will go and check the oil and see if I feal any filings. I dont currently have a manual for this engine but I do have a lot of mechanical experience as well as some marine mechanical experience. I have a book on the way but it will be a few days before it is here. I was really hopeing for it to be something other than the gears but if thats what it is then Ill have to take care of it.

Any idea what could have suddenly caused the gears to go bad like this? I checked the gear oil before we left for the lake and everything seemed fine.

Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Well, I checked the gearoil and find a few metal filings larger than normal so I went ahead and took the gearcase apart. I found just what I was hopeing I wouldnt find. There are 5 teeth broken on the forward gear and 4 broken on the pinion gear. The teeth are not broken completely but just enough to cause the noise. I guess it is safe to say I shut the engine down just in time. The reverse gear appears to be fine but due to the nature of the components it will be replaced with the others.

I only have one question, All the bearings look, feel, and measure out fine. They appear to have no damage or wear at all. Will the bearings all be ok to reuse when I replace the gears?

Thanks
Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Well - I can't say that you saved much of your lower end based on what you found but if you need to replace two of the three main items I'd consider the reverse gear if it's not that much more to do so. If it is costly to do so, then as long as it's still in good shape you're probably good to leave it.

I must give you credit for getting in there without a manual. Putting it back together will require some specifications that you just can't guess at.

Andre

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Bearings are normally reusable as long as they aren't scratched, chipped, whatever..... and still have a mirror like finish.

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Andre: I have some experience with disassembly on gearcases, I just dont have a manual on this particular model so it wasnt really too hard to get the case apart. I found an OEM gearset for $220 which includes forward/reverse/and pinion gears as well as clutch dog so I will definately be replaceing all the gears. This unit wont be put back together until my manual gets here, I like to be sure everything is strictly by the book.

Joe: I cleaned all the old oil off the bearings for inspection and there are no signs of any flaws in the bearings. They all have a nice shiny finish as well. Oh, after inspection I placed them in oil to prevent any possible flash rust.

Thanks for all the help. I really didnt want to find out it was the gears but after I found the set for $220 I felt a little better about the repair.

Robert

Re: 1993 Johnson 48hp Clicking sound in Gearcase

The gear set, usually just the pinion and forward gear. If you have the part number of that set, what is it?

Re: 1993 Johnson 48hp Clicking sound in Gearcase

Here are the part numbers: 397627 Gearset 12:29, 332489 Gear-Reverse, 332491 Shifter-Clutch dog.

Robert