1960 johnson seahorse.. water leak cant find it

[Cotton_87]

i have been messing with this motor for the last month or so... i got it off a friend to try out. for a kicker motor. well when i got it it already had water in the lower unit. so i replaced the o ring on the prop shaft and resealed both joints the upper and the lower. after a couple of uses i noticed it was still getting water in it... so heres my findings after some tests in a bucket. with the oil drained and the plugs in. i soaked it for about a day but only submerged the prop and then checked to see if there was any water in it... none so then i submerged it all the way past the upper joint... let it sit for a day and also ran it for a little bit... pulled it out of the bucket and pulled the plug some water came out.. not alot. it seems that the water that gets into the exhaust housing is leaking into the gearcase??

 

[tx1961whaler]

Re: 1960 johnson seahorse.. water leak cant find it

Under the water pump plate (drive shaft seal) or the shifter rod (o-ring)

 

[EN2]

Re: 1960 johnson seahorse.. water leak cant find it

First of all, what model is this you are working on? There are several places water can enter the gearcase. What is needed is a pressure test on the gearcase. When it is pressurized,you will be able to hear where it is leaking, or by submerging in water. Any thing this old will proably need a compete resealing. The seals will be as hard as a rock. Also inspect prop shaft, drive shaft for a groove around sealing surfaces. Another suspect seal would be the shift shaft seal. An oem service manual would be big help.

 

[Mas]

Re: 1960 johnson seahorse.. water leak cant find it

Yes, get it pressure/vacuum tested. Static tests by soaking it will not pinpoint the leak. When the motor is running, the gear oil heats up slightly and causes pressure differences in the gearcase and again when it cools.

The gearcase must be pressurized to find the leak.

MAS

 

[Rick.]

Re: 1960 johnson seahorse.. water leak cant find it

The deeper the water the more head pressure that is exerted on the lower unit. There is no way you can be certain of the leak location with the method your using. A prop shaft seal that doesn't leak in 6 inches of water might well leak in 12 inches. I agree with the boys above. Rick.

 

[sheboyganjohn]

Re: 1960 johnson seahorse.. water leak cant find it

Since you did the plug seals and resealed the lower half to the upper and put in a new prop shaft seal I would suspect the shift o-ring. If it is like the one on my 40hp 1960, then it most likely has never been changed. Assuming your lower is put together the same way (hint need the model and HP of your motor), a quick and dirty way to check the shift o-ring is to pull the drive shaft out of the lower unit. Put some grease (light coat) on the drive shaft to make a good seal with the seal. Spray some soapy water on the shift shaft seal area (do not get any into the drive shaft hole). Push the drive shaft back into the lower unit. The drive shaft will creat just a little pressure in the lower unit, if you see bubbles around the shift shaft you found your leak.

I learned this one after changing all the seals in my lower except the shift shaft. I was putting the drive shaft into the lower unit (it was wet from just being run) and could see water bubbles around the shift shaft. One item of note, my shift shaft seal was completely shot so it did not take much pressure to push air out of it. If you have a slow leaker, this method may not produce enough pressure to show the leaki.

 

[Cotton_87]

Re: 1960 johnson seahorse.. water leak cant find it

that sounds like it could be the coulpert... the local marina suggested a some bushing on the driveshaft that is over $100.. there expensive tho. I did forget to mention its a 10hp! now when i unbolt the mid section it only comes down about an inch. to get it to come off would i have to unbolt the bottom fin and remove the prop shaft etc..??

 

[freddyray21]

Re: 1960 johnson seahorse.. water leak cant find it

on the side of the leg is a cover held on by two screws. remove the cover and you will find the shift linkage. Undo the bottom bolt only and the shift shaft will slide out letting you remove the lower unit. I am a bit confused as to what you resealed. You say joints so I am thinking you resealed the joint between the lower and the leg? It does not need a seal at all. the other joint where the lower comes apart just above the skeg take a spagetti seal and since it appears you did not get it apart all the way. (you can't unless you take the shift rod loose or the phillips screw at the bottom, which is a bad idea) then all you did perhaps was put some sealant on it which will not work generally. There are three seals and five gaskets that need to be replaced to do it right. Below the water pump is the driveshaft seal. On the prop shaft is a prop shaft seal and under a bushing where the shift rod goes through is a shift shaft seal. The five gaskets are the spagehetti seal and the two gaskets that go on the fill and vent screws. the water pump wear plate gasket and the last is an oring type that goes on the phillips screw holding the shift yoke. Not a really bad job. with the right tools I can do one in a hour and I am slow. A complete seal kit can be bought here in Iboats at: http://www.iboats.com/mall/partfind...gd_poid=110557&gd_row=12&**********=608583315

 

[Cotton_87]

Re: 1960 johnson seahorse.. water leak cant find it

the 2 joints i did reseal, was the very bottom section that holds the prop shaft, i went ahead and put silcon on it too altho it does have a rubber seal on it... the other section i sealed is the joint right above the exhaust 4 bolts.. i am new to working on boat motors so i'm not very good with all the terms. lol... but i did figure out how to remove the shift linkage and remove the whole lower unit freddyray21. now where the shift linkage passes thru by the water pump thats a bushing correct? and theres a seal under it? how do you remove the bushing?