1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

[bergiesue]

Hi!

I'm new to the forum and I have lots of questions that I'm sure you guys will help me with. We bought a 1974 Glastron GT-160 with a 115hp Johnson outboard about 5 weeks ago.

Last weekend on the lake (about our 5th time out in the boat), we cruising along at a moderate speed and then "POP" from the lower unit on the Johnson. We stopped looked around to make sure we didn't hit anything (we didn't), then we were able to move forward for a few yards but the lower unit was making a rattling noise and we lost all forward power. We tried reverse and made it a few yards closed to the ramp and then suddenly we had no power at all. Luckily we got a tow to the dock by some very nice boaters.

We were planning to take the lower unit apart to see what damage was done in there - drained out the oil and saw rather large (1/8") chunks of metal we stuck on the drain plug and more came out with the oil. The oil was horribly burnt. The prop & shaft spin freely in forward, reverse, and neutral gears but we can feel a little grinding in there when we spin it.

We have the repair manual for the boat and thought we'd better go to the local boat shop to see what they thought about the "special tools" listed in the manual. The repair man told us that we basically had no business inside the lower unit because it is so complicated and extremely difficult to get it all put together correctly without tearing up all our new gears and then quoted us about $1000 for a rebuild - around $650 of that was gears and seals and other parts. He also said that if we start taking it apart to look in there, he can't work on it at all - doesn't like boxes of parts. My fiance is a machinist and thought the whole project looked easier than what the guy said it would be but after talking to the repair guy we don't know what to do.

I came home and started reading through the lower unit forums and then looked on Ebay for a used lower unit. I found this:

"Johnson Evinrude V4 Outboard Motor Lower Unit Assembly. Complete.-Came off of a 1977 model 115HP with a 20 in shaft length.-Will work on a vast array of the V4 cross flow motors1973to1978 this unit was Vacuum and pressure tested to 15 psi.-No water or metal shavings in gear oil was present. All shafts spin true and free. Spines are in good shape. - Shifts easily into forward - neutral ? reverse. sold as is " $200.

http://cgi.ebay.com/ebaymotors/ws/e...50304199692&ssPageName=ADME:X:RTQ:MOTORS:1123

It seems easy enough for us to replace the whole lower unit. I'm concerned that this unit may not fit our motor - I checked with the seller and he said it will and the only thing we should need besides basic tools is oil to fill it back up. The price seems reasonable to me. What do you guys think?

I'd like advice as to what you think may have broken in there and what we should do about it - rebuild ourselves, have it done at the shop, or get the used one from ebay. The auction has about 1 1/2 days left on it and I don't want to miss out on the part if this is the best answer for us.

THANKS!

-Heather
Colorado Springs, CO

 

[crb478]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

it will fit, I would buy it especially if the seller has good feed back.

 

[ezmobee]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

I think that eBay unit would a very wise purchase.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

Thanks guys!

I went ahead and bid on the used unit. Let's hope I get it!!!

I will let you guys know if I get it and if we need any help with installation tips!!!

-Heather

 

[iwombat]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

If you get it, you should plan on replacing the water pump.

 

[witchcrafter]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

if you dont get it go to craigslist.org and search around your area for things. i would do as iwombat stated also and go ahead and replace the water pump.

 

[iwombat]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

Also, if you've got a machinist that can help you, there's no reason you can't tackle a rebuild on the one you've got. (The ebay unit should still be plan A.) You'll need to find a monster set of snap-ring pliers though.

 

[witchcrafter]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

and make sure you dont damage the tubes that run thru the exhaust housing when putting back togeather. these push water to the motor.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit UPDATE

Re: 1974 Johnson 115 hp lower unit UPDATE

We just pulled the old lower unit off. Surprisingly, we didn't have any problems at all. What will we need to buy to install the new one? Are there and seals that we need? Do we need a whole new water pump or just the waterpump repair kit?

THANKS SO MUCH FOR ALL THE HELP!

 

[witchcrafter]

Re: 1974 Johnson 115 hp lower unit UPDATE

Re: 1974 Johnson 115 hp lower unit UPDATE

a NEW water pump not a repair kit. i didnt have any gaskets i had to replace. now there should be 1 or 2 copper tubes in the housing (you will see if you look up in there) make sure you dont damaged them.i did on my first time.

 

[ezeke]

Re: 1974 Johnson 115 hp lower unit repair/replace?

Re: 1974 Johnson 115 hp lower unit repair/replace?

You might want to wait until you see the condition of the pump on the Ebay gearcase. Between the one that you have and that one, you may need only a new impeller.

The one other thing that you should consider replacing is the inner exhaust seal (PN 314937) that seals the exhaust tube to the gearcase.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit UPDATE!!! - help!!!

Re: 1974 Johnson 115 hp lower unit UPDATE!!! - help!!!

OK guys - I received the Ebay unit on Thursday and spent all day yesterday cleaning it up. It was used in salt water before (that part wasn't advertised!) so it was totally encrusted with salt - gross! It even had one bolt "salted" in. We took apart the water pump and it was SPOTTLESS inside - almost no wear on the impeller, no salt, inside surfaces smooth and clean. Almost like the water pump had been replaced recently. We installed it and went for a test run today. Forward gear works GREAT - super smooth and seems quiter than our old one. The problem is WE HAVE NO REVERSE GEAR. When we put it into reverse we get a slight backward movement and a grinding/clacking noise. I am NOT happy. Any ideas on what may be wrong? Is there anything we could have done wrong with the installation that would cause this (hopefully)? Or is it time to give up and call the mechanic for a rebuild..... THOUGHTS???

 

[freddyray21]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP!!!!

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP!!!!

Did you check the shifting before installing? It could be several things. I am assuming this is not an electric shift. I would first check to see the shift linkage is correct. It is important when lining the shift rod up that the lower unit and the shifter is in the same gear. After putting it together and before installing the bolt I always put them in reverse at the shift handle as it will push the rods where they need to be. Once that is done leave it in reverse then put the bolt in the shift linkage. Should be fine then. If not the linkage it could be a reversed clutch dog. Please understand this motor is a lot newer than anything I usually work on, but on the older motors the clutch dogs would get worn and since forward would wear much more quickly than reverse the practice of reversing the clutch dog gave you a good forward again and a poor reverse. Not saying this is the problem, but could be.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

I think everything was in neutral then we installed it - guess I should have paid more attention. We also noticed today that the boat seemed to be slightly engaged in forward gear when we were starting it in neutral - jumping forward a little bit.

I was reading some other posts and came up with this: The shift rod connector screws on to the top end of the shift rod. On our old unit, this connector was screwed down all the way - no threads visible below the connector. On the Ebay lower unit, this connecter had about a 1/4" of threads visible below it and it was seized up tight - couldn't get it off to clean it - its really glued on there! This makes the Ebay shift rod longer than the old one. Since reverse has the shift rod pulled UP and the rod is too long, it would not go completely into gear. This would also explain it lurching forward in neutral as well becase it wouldn't be able to completely disengage from forward. If this is the case, we drop the lower end, somehow loosen that glued-on shift rod connector and then screw it down all the way on the threads. Does this sound plausible? Would 1/4" of length on the shift rod make that much of a difference?

Another question: If it safe to run the motor in gear with just the earmuffs and the garden hose or do we need to take it back to the lake to test forward and reverse? (Its a 40 mile trip to the lake so I hope the answer is yes!!)

-Heather

 

[ezeke]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

The swivel barrel at the top of the shift rod is the only adjustment for tthe shift rod. It should be turned down until seated and then out no more than two turns to face the flat surface towards the driveshaft.

Once in place, disconnect the shift cable and confirm that you can manually shift to forward and reverse by raising and lowering the bellcrank with the shift lever. If you turn the flywheel with the plugs out, this will be easier. Edit: Leave the gearcase in neutral for cable connection.

Move the control arm fully forward and back to neutral and adjust the cable using the trunnion nut at the engine until the cable slips back on the shift lever without any movement of the shift lever.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

Will do! THANKS for the advice! I'm going to go drain it and drop it right now so that I can start on it first thing tomorrow!

Can you answer the earmuff question for me?

 

[Joe Reeves]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

It's okay to run the engine on a flushette (garden hose) and to shift into gear (forward and reverse), BUT do not open the throttle very far.... 1800 rpm tops. Have the water pressure turned on full force.

As Zeke states, free that top barrel shift connector, screw it all the way down gently, then back it off slightly until the vertical portion faces forward (flat portion faces back).

 

[ezeke]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

Edit: To Joe Reeves, didn't see you coming, sir!

There is no technical problem with running in gear on muffs as long as you don't exceed 1500 RPM which you would not do in neutral either.

The problem is that it is dangerous for you, pets and children, so be careful.

 

[freddyray21]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

sounds very much like a linkage situation and these guys have you on the right track.

 

[bergiesue]

Re: 1974 Johnson 115 hp lower unit UPDATE/HELP: NO REVERSE!!!

THANKS SO MUCH FOR ALL THE TIPS! I hope we're right about the linkage adjustment - that would sure be a big relief for me! I got the unit drained and taken off again tonight. It shifts into forward and neutral easily, reverse takes just a little bit more effort but it goes in. The prop and driveshaft turn the right directions in both forward and reverse. I can't feel any grinding or catching in any of the gears - turns really smoothly. I got the shift linkage loosened up and cleaned all the threads so that it can actually turn now. Tomorrow I will reinstall the unit and do a test. Right now I have the linkage tightened all the way down and backed off about 1/2 turn to face the right way. It's about 4 or 5 turns tighter than it was before. Both the lower unit and the controls on the boat are in reverse gear. Anything else I should do before I reinstall it?

Keep your fingers crossed for me!!!