So I now own a 1978 55hp Johnson outboard

[madtowndrunkard]

I know nothing about boat motors so here it goes. I purchased a 16 foot fishing boat w/ a 1978 55hp Johnson. It's electric start, steering wheel, shifter, etc. It ran good as far as I could tell. I've ran it wide open and it didn't studder or anything like that. It starts right up most of the time. Occasionally after running it a while, then shutting down, I'll try to restart it and it will not start....like maybe I flooded it? If I let it sit for about 20 minutes and turn the key w/ the choke off it will then restart. I've been stuck on the lake for 30 minutes before trying to restart it - then suddenly it starts? why does it do this? Did I flood it?

Last week I decided to change the plugs, I was told the plugs were burnt up pretty good when I showed them to the parts guy at the boat shop. I then drained he lower unit and the grease came out yellow, thick, and stinky. I filled it with new grease, and I was told the lower unit seals must be bad.

So I took the boat out after changing the plugs and grease and it stuttered and would kill while idling about 5 times before I could get it into gear and start moving. When I accelerated it bogged down and would quit. I restarted it and let it idle for about 5 minutes, then took off and it ran better then ever. I mean it REALLY ran well - I nearly killed my self going so fast and hitting some pretty big waves. I'm wondering if the plugs were not firing in both cylinders before? It never ran so fast w/ such good acceleration and top speed - though I didn't think it was slow before.

I was told a seal kit for my motor is about $65 and it's pretty easy to install. Is this true? or should I take it in and have them do it for about $250? Were can I find instructions to do this?

I'm also wondering if there is anything I should have checked on this motor? Timing? Water pump? I've heard that I should check the impeller? ( I have no clue what that is) Is there anything that should be greased? Any suggestions would be greatly appreciated.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

I forgot to mention, when I changed the plugs, I also added about 8oz of SeaFoam to about 4 Gal's of fuel. So maybe that caused the engine to choke and studder at first?

The seafoam was suggested to me by a small engine mechanic that worked on my chain saw.

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

My first suggestion, and a strong one, is to get a manual asap. Your starting procedure could be to blame, read the thread in the FAQ concerning this. A bath and rebuild may also be in order for the carbs. Impeller replacement is very important, cheap part, but if it fails, can be very expensive.

Here is the thread for the starting procedure.

http://forums.iboats.com/showthread.php?t=225510

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

I would also do a spark check and compression check, good to know to start troubleshooting. Both tester can be bought fairly cheap at most auto parts stores. If you need any help with this, let us know. As far as the impeller replacement goes though, I would reccomend having a manual for your first time. Also when you changed the lower unit oil, did you replace the drain and vent screw gaskets, that is the number 1 spot for water intrusion.

Here is a link to the manual you will need, cheap and pretty much brand new, 22 bucks. Worth every penny.

"http://cgi.ebay.com/ebaymotors/1978-JOHNSON-55-HP-OUTBOARD-MOTOR-SERVICE-MANUAL-NEW_W0QQcmdZViewItemQQcategoryZ26453QQihZ016QQitemZ260039110420QQrdZ1QQsspagenameZWDVW"

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

I would also do a spark check and compression check, good to know to start troubleshooting. Both tester can be bought fairly cheap at most auto parts stores. If you need any help with this, let us know. As far as the impeller replacement goes though, I would reccomend having a manual for your first time. Also when you changed the lower unit oil, did you replace the drain and vent screw gaskets, that is the number 1 spot for water intrusion.

Here is a link to the manual you will need, cheap and pretty much brand new, 22 bucks. Worth every penny.

"http://cgi.ebay.com/ebaymotors/1978-JOHNSON-55-HP-OUTBOARD-MOTOR-SERVICE-MANUAL-NEW_W0QQcmdZViewItemQQcategoryZ26453QQihZ016QQitemZ260039110420QQrdZ1QQsspagenameZWDVW"

No I didn't replace the gaskets, they were intact though...they are made of white plastic correct?

Where do I get a manual?

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

I would also do a spark check and compression check, good to know to start troubleshooting. Both tester can be bought fairly cheap at most auto parts stores. If you need any help with this, let us know. As far as the impeller replacement goes though, I would reccomend having a manual for your first time. Also when you changed the lower unit oil, did you replace the drain and vent screw gaskets, that is the number 1 spot for water intrusion.

Here is a link to the manual you will need, cheap and pretty much brand new, 22 bucks. Worth every penny.

"http://cgi.ebay.com/ebaymotors/1978-JOHNSON-55-HP-OUTBOARD-MOTOR-SERVICE-MANUAL-NEW_W0QQcmdZViewItemQQcategoryZ26453QQihZ016QQitemZ260039110420QQrdZ1QQsspagenameZWDVW"

No I didn't replace the gaskets, they were intact though...they are made of white plastic correct?

Where do I get a manual? ....nevermind......thank you

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

Yes, even though they are intact, from now on everytime you change the fluid it is reccomended to change the gasket, grab a handful of them on ur next trip to the BRP dealer.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

Yes, even though they are intact, from now on everytime you change the fluid it is reccomended to change the gasket, grab a handful of them on ur next trip to the BRP dealer.

If I buy a seal kit of the lower unit, is this an easy enough job to do my self?

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

That depends on the seal that you are replacing, and if you have your manual. They can be done fairly easily though. Was the first bit of oil to come out milky white? thick and stinky isnt necessarily water intrusion, more age of the oil, not to say though that you DONT have a water intrusion issue. Did the gearcase seem full when you emptied it? Same amount came out as you put in? If it was, I would change those gaskets, and wait until the next time you change your oil, check the first bit that comes out, since the water will sink to the bottom of the oil and exit first.

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

Pull the prop off and see if you have any gear oil residue around the shaft. That should tell you the condition of the prop seal.

Also use the full synthetic lu oil.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

That depends on the seal that you are replacing, and if you have your manual. They can be done fairly easily though. Was the first bit of oil to come out milky white? thick and stinky isnt necessarily water intrusion, more age of the oil, not to say though that you DONT have a water intrusion issue. Did the gearcase seem full when you emptied it? Same amount came out as you put in? If it was, I would change those gaskets, and wait until the next time you change your oil, check the first bit that comes out, since the water will sink to the bottom of the oil and exit first.

It came out yellow or creamy white...all of it. It seamed like I put a little more in it then what actually came out.

I just picked up the seal kit. It includes a whole bunch of seals and rings - plus new screws and gaskets. I'm guessing there are 20 different gaskets and seals in this kit. yikes.

I also picked up a new empeller. The guy at the Johnson dealer told me to take a good look at the water pump caseing - if it seems warn at all - that I should then just get a whole new water pump kit and replace the whole thing. (for any extra $50)

The Johnson dealer here also gave me a phone number to a company that prints old manuals for Johnson/OMC right in Milwaukee, Wi (an hour away from me) Ken Cook Company.

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

The ken cook company is good, but are a bit more pricey than the link that I sent you. He gave you good advice about the water pump, if it looks scored or damaged, replace it. You probably wont use all the seals, it is most likely a universal kit, so there will be ones for models other than yours. The manual will help you with this. Oil the blades of the impeller before install, it will ease the start up. Grease the splines of the driveshaft, and you will need a can of gasket sealing compound as well for the impeller housing plate. You may be tempted to "tighten" the shift rod, it may look "loose", but dont, it has tight tolerances and adjusting its length will mess up your shifting. Also might want to clean out the water intake area while your lu is down, and when bolting it back up, make sure that the water line goes smoothly into the grommet on top of the impeller housing, they easily get knocked to the side, or shoved into the impeller housing, restricting water flow and causing your motor to overheat. You will understand once you start. Good luck.

Here is a link to an exploded view of your lower unit apart. It may help

"http://epc.brp.com/default.aspx?brands=ej&lang=e"

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

Thanks alot for all your help. Once I get a manual I'm sure I'll be back with more questoins.

As for the kit being universal, I don't think it is actually. I do think it's for my motor. This shop is the only certified Johnson OB dealer and repair shop in the area....not that it means anything. But they did tell me they use Johnson parts. I'll give them a call just to make sure. I know I'll be freaking out when I have 10 left over parts.

With the seal kit and immpeller they gave me the same parts diagram that you just gave me with name and number for each part.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

One last question.

I've read on here a lot about your motor's RPM's. I do not have a tachometer on my motor. Is this something I can put on relatively cheap and easy?


oh yea and fuel - does it matter what octane you use?

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

The ken cook company is good, but are a bit more pricey than the link that I sent you. He gave you good advice about the water pump, if it looks scored or damaged, replace it. You probably wont use all the seals, it is most likely a universal kit, so there will be ones for models other than yours. The manual will help you with this. Oil the blades of the impeller before install, it will ease the start up. Grease the splines of the driveshaft, and you will need a can of gasket sealing compound as well for the impeller housing plate. You may be tempted to "tighten" the shift rod, it may look "loose", but dont, it has tight tolerances and adjusting its length will mess up your shifting. Also might want to clean out the water intake area while your lu is down, and when bolting it back up, make sure that the water line goes smoothly into the grommet on top of the impeller housing, they easily get knocked to the side, or shoved into the impeller housing, restricting water flow and causing your motor to overheat. You will understand once you start. Good luck.

Here is a link to an exploded view of your lower unit apart. It may help

"http://epc.brp.com/default.aspx?brands=ej&lang=e"

Ok I lied, I've got more questions....I know this is a stupid question, but you suggest oiling the impeller and greasing the splines of the driveshaft. What type of oil and grease should I use to do this?

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

As far as oiling the blades of the impeller, just use the oil that you use in your lower unit if you have any leftover. I use Marine Grease, available anywhere, for the splines on the driveshaft. You will be able to get the marine grease, lower unit oil, and gasket sealing compound at the OB dealer that you spoke of. Dont bother getting any octane fuel greater than 87, you're just wasting your money, the 87 regular is fine.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

The ken cook company is good, but are a bit more pricey than the link that I sent you. He gave you good advice about the water pump, if it looks scored or damaged, replace it. You probably wont use all the seals, it is most likely a universal kit, so there will be ones for models other than yours. The manual will help you with this. Oil the blades of the impeller before install, it will ease the start up. Grease the splines of the driveshaft, and you will need a can of gasket sealing compound as well for the impeller housing plate. You may be tempted to "tighten" the shift rod, it may look "loose", but dont, it has tight tolerances and adjusting its length will mess up your shifting. Also might want to clean out the water intake area while your lu is down, and when bolting it back up, make sure that the water line goes smoothly into the grommet on top of the impeller housing, they easily get knocked to the side, or shoved into the impeller housing, restricting water flow and causing your motor to overheat. You will understand once you start. Good luck.

Here is a link to an exploded view of your lower unit apart. It may help

"http://epc.brp.com/default.aspx?brands=ej&lang=e"

Hightrim

Thanks for your advice. I ordered my manual from the ebay link you gave me. The manual arrived, it's like new - but printed in 1977.

I just drained my lower unit again and about a couple table spoons of water came out first. So there is definately a leak. The funny thing is I can't find any oil leaking out anywhere. I've removed the prop and the shaft looks pretty good. I'm now headed up to the OB dealer to get the Marine grease and gasket sealing compound.

Do I only use the gasket sealing compound on the water pump housing? Or do I use it on all of the gaskets and seals?

 

[HighTrim]

Re: So I now own a 1978 55hp Johnson outboard

Those original manuals are by far the best, ordering it was a wise choice. That original manual should cover it as you go as to where you will need the compound, such as on the gaskets for the thermostats, etc... Next you will need to locate where you have a lower unit leak, by a pressure test. Or you could just replace all seals, usually if one is gone, the others arent far behind anyways.

pressure/vacuum test a lower unit:

a) drain the gear oil
b) use an appropriate adapter with a gauge tee'd in to apply pressure or vacuum. No more than 15 psig for pressure. You can use a bicycle pump or any other compressed air source for pressure. For vacuum, you need a vacuum pump.
c) LU should retain some pressure or vacuum for 45 minutes minimum.
d) If pressure doesn't hold, submerge LU in water to find leak source [possibilities: drive shaft seal, prop shaft seal(s) (usually two), shift shaft seal and the fill/drain screw washers.]
e) replace offending seal(s) as required.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

Those original manuals are by far the best, ordering it was a wise choice. That original manual should cover it as you go as to where you will need the compound, such as on the gaskets for the thermostats, etc... Next you will need to locate where you have a lower unit leak, by a pressure test. Or you could just replace all seals, usually if one is gone, the others arent far behind anyways.

pressure/vacuum test a lower unit:

a) drain the gear oil
b) use an appropriate adapter with a gauge tee'd in to apply pressure or vacuum. No more than 15 psig for pressure. You can use a bicycle pump or any other compressed air source for pressure. For vacuum, you need a vacuum pump.
c) LU should retain some pressure or vacuum for 45 minutes minimum.
d) If pressure doesn't hold, submerge LU in water to find leak source [possibilities: drive shaft seal, prop shaft seal(s) (usually two), shift shaft seal and the fill/drain screw washers.]
e) replace offending seal(s) as required.

The seals in the water pump were in bad shape but the impeller looked pretty good. I'm replacing it anyway. The pump was really dirty so I cleaned that up and it looks good. After I droped the LU everything was wet with water on the top. (the small pockets on the LU had water in them - don't know if that is normal or not?)

The seal kit came with a gasket that fits perfectly under the impeller housing (on top of the plate) or under the impeller plate - I'm not sure wich? The manual says nothing about a gasket in or under the water pump - only a seal. So I'm guessing I just don't use that gasket? There was nothing there when I took it apart.

 

[madtowndrunkard]

Re: So I now own a 1978 55hp Johnson outboard

I think I ruined the seal housing that fits over the drive shaft. I was trying to remove a ring out of the seal housing and out came a round spring and I tore the rubber gasket that was in there. I finally got that driveshaft oil retainer ring out but the rubber ring that fits inside the seal housing is all tore up and the spring that was inside the housing is now ripped out. It seems like that housing should come apart in two pieces but it doesn't. I don't know how the heck they got that rubber seal and ring in the middle of that seal housing.

I'm going to take that part in and show it to the Johnson dealer, I don't know what the heck I did there. There are some grooves insde that seal housing as well, so maybe it needed to be replaced anyway?

I can't figure out how to pull out the drive shaft and propeller shaft. The manual is showing that I need these special tools that I don't have. It looks really complicated from here on out. I'm ready to give up and bring it in to the Johnson mechanic. I'm a little irritated with my problem I had with the drive shaft seal housing as well. I'm really afraid I'm going to screw something up.