77 Johnson 85 Horse lower unit removal

[MRneatfreak]

The service manual is useless in this project. I got all four 9/16, one 5/8 and the two 7/16 bolts in the underwater side taken out. My buddy helped me with that then when it came time to disconnect the shift linkage said he had to leave,.

From what I can see there is a rivet holding the linkage under the carbs that connects to the shift rod and disappears in to the lower unit? I don't see a cotter pin or snap ring for a easy disconnect? Do I need to remove the powerhead cowlings underneath to facilliate this project?

I am removing to install a new water pump kit.

Ok just found this post:
http://forums.iboats.com/showthread.php?t=529703

Crazy how the search on the forum turns up no results, but google it and it show right up.

So the bell crank just opens up and it falls down right?

Confused on the Vernatherm, is it under the square looking plate between the heads or somewhere else?
Please advise.

 

[boobie]

Re: 77 Johnson 85 Horse lower unit removal

Right ! The thermos are under the cover between the cyls at the lower part of the block on the back.

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

The two bolt heads on the housing of the Vernatherm, were starting to round off. So I soaked em in deep creep and moved on to remove the lower unit to replace the water pump kit.

Upon reinstall of the lower unit, I got about 3/4 of inch left before it was mated, and it stopped moving by hand. I know the drive shaft splines are engaged because I can move the prop and hear the pistons moving, and I can see the shift linkage not binding. So can I draw the two pieces together with the bolts or should it move freely together by hand?

I ordered a factory manual off of ebay for $35, just have to wait for it get here. I hope it is more detailed than that crap shop one I bought at the marina for $45.

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

I ended up removing the bolts again and pulling the unit out and checking to make sure I didn't bend the metal water pipes in the middle section. Then pushed it together again, this time it went further, then bolted it all together. Getting the shift linkage to go line up was a pain.

I think I found part of the reason why there was no water coming out before I installed the water pump kit. The inlet passages in the lower unit were plugged with silt and bugs, the impeller actually looked ok. But replaced it all anyway.

 

[boobie]

Re: 77 Johnson 85 Horse lower unit removal

Hope you get a good manual. Seloc and Clymer suck. Also hope you didn't have any lube ON TOP of the drive shaft splines when you installed the g/c.

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

What would happen if there was lube on the splines on top of the driveshaft? There was some old black stuff on there already, cleaned it off and ...:facepalm:

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

It so happens I did grease those splines on the upper driveshaft. It makes no sense not to.

I read on online for a smaller johnson and it said to make sure you DO grease the splines?
http://www.sschapterpsa.com/ramblings/Lower_unit.htm

 

[Will Bark]

Re: 77 Johnson 85 Horse lower unit removal

He's talking about any grease on the top of the shaft which would prevent shaft from seating fully in the crank.

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

Oh, ok, yeah I ran my greasy finger across the top of that shaft but didn't put a big glob of synthetic grease on top. Whew.... Wasn't looking forward to pulling the lwr unit off again, and messing with the shift linkage.

PIA when you are working by yourself. Had to call my young boys out last night to hold the flashlight while reassembling everything. The older I get the more I hate working after sunset. Starting to realise its easier to go to bed early, get up at sunrise and let the sun provide the light.

Thanks, for the clarification. The people that contribute to this website ROCK

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

After playing around with the fuel system, I got the 85 horse to start on the first try However water at one point was coming out the two holes in the midsection, but then stopped after the engine died and I restarted it?

I don't know how water is supposed to flow? Does it come down from the top the cylinder heads, then flow down and out through the two rubber hoses, into the Vernatherm and then out the two holes in the midsection? I removed one hose to see which way water was moving, and there was nothing there, with the engine running, either from the head or the Vernatherm? I tried the muffs on a slow and moderate trickle, no change. Also there was a little water escaping where the lower unit mates to the midsection? Do I need to remove the lower unit again and try to get a better seal in the midsection with the internal water pipes? Or should I go to the boat docks and see how it does in the water?

I never did replace the vernatherm, as I'm afraid those two bolts are going to snap off, because the bolt heads were starting to round off, and the bolt itself wasn't moving.

Another thought: Is there anywhere else I can verify I have water pressure?

Any thoughts on Salt Away Solution? I think its been a while since this motor fired off, the previous three owners gave up on getting it to run, I got lucky with a used powerpack. So needless to say things are salt crusty inside? Maybe there is a salt crumb blocking a passage and that why its not peeing?

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

I was thinking that if I cant service the Vernatherm (thermostat) due to possibly breaking the bolts. Then I would take those rubber hoses off that link the heads to the Vernatherm, and try this procedure designed to remove salt deposits from a buildings' exterior:

If the coating is largely calcium carbonate or calcium sulfate, it adheres rather strongly and is difficult to remove by brushing. The practice developed in this case for masonry surfaces, has been to saturate the structure as thoroughly as possible with water, and then wash with diluted muriatic acid, followed immediately with an alkaline wash, then washed with water. The acid recommended is five (5) parts hydrochloric to one hundred (100) parts water, or twenty (20) parts vinegar to one hundred (100) parts water. The alkaline wash recommended is diluted household ammonia.

The most common materials we have in an outboard are Rubber, Plastic, Aluminum, Iron, Stainless, Zinc, and Copper. Not sure what the Vernatherm is made of? The idea was to unclog the thermostat area, and not allow the solution to enter the lower unit or impeller area. What do you think?

 

[MRneatfreak]

Re: 77 Johnson 85 Horse lower unit removal

I tried straight vinegar from the top of the Vernatherm and it ran out the two exhaust ports. Didn't foam up or anything. Chased it with water still no reaction. But it showed me that the passage isn't blocked. I ran the motor on muffs for a while and it started to spit water out of the midsection. Still not pleased with some water escaping between the lower and midsections,:facepalm: