1993 Johnson 50 HP replacement options?

[johnsland8]

I just purchased a boat with a 1993 2-cyl Johnson 50 HP motor. Model VJ50TLETB. PO diclosed that the motor was bad. Looks like it has one bad cylinder, Cyl 1 tested at 155 psi, Cyl 2 tested at 120 psi. I guess the motor will start and run OK initially, then bogs down as it gets warm, makes sense I guess. Anyway, a rebuild seems expensive with machining, etc. so I was looking into just replacing the powerhead with a used or reconditioned one.
My question is, where can I find information that shows me what options I have. I'm not married to 50 HP. Are there other HP and Year options that would work? Can I also use Evinrude from the same years? Where can I find this info? I have done some searching but could not find an easy way to determine this...
Thank you very much for any help you can provide...

 

[HybridMX6]

Re: 1993 Johnson 50 HP replacement options?

I'm sort of in the same situation as you, so I will be interested to see what others have to say. I have a fully functional motor on my boat, but I just bought a '94 60hp Johnson that has 115, 115, 85, according to the PO. I'm going to do my own testing and go from there, but the motor sure is clean under the hood. Hope some others can give you (and I) some good advice.

 

[johnsland8]

Re: 1993 Johnson 50 HP replacement options?

Anyone?

 

[Dhadley]

Re: 1993 Johnson 50 HP replacement options?

As for the 93 50, any 2 cylinder 50 from 1981 thru 2005 is the same powerhead. Either Evinrude or Johnson. A 2 cylinder 60 hp powerhead from 1980 thru 85 will work too. A 2 cylinder 55 hp commercial powerhead from 1980 thru 2000 will work also. Don't beat yourself up over the numbers, you'll never see the difference between your 50 and a 2 cylinder 60. There are some older powerheads that will fit but the internals are different and you may run into getting the wrong parts down the road.

As for the 94 60 hp 3 cylinder, any 56 cid 3 cylinder powerhead will work from 1986 thru 01. Basically if it looks like your powerhead (single plate over exhaust) it will work. A 49 cid 3 cylinder (3 plates over exhaust) will not work.

In either case you can go to the Evinrude site and match parts to find the interchanging years. Start by comparing powerhead base gasket numbers.

 

[JB]

Re: 1993 Johnson 50 HP replacement options?

http://www.boatmotors.com/motorparts/

 

[tashasdaddy]

Re: 1993 Johnson 50 HP replacement options?

HybridMX6, hijacking at thread is very rude, please start you own thread. we will now address johnsland8, question.

what makes you think you need a rebuild? what have you check other than compression? have you pulled the head to see if it has a bad head gasket. have you inspected the cylinders and piston?

Don't go tearing something down that could be an easy fix.

 

[HybridMX6]

Re: 1993 Johnson 50 HP replacement options?

I wasn't intending to do that, I was just noting I would be interested to see what people have to say. Sorry, my apologies to johnsland8

 

[tashasdaddy]

Re: 1993 Johnson 50 HP replacement options?

if you start you own thread you will get all the specific help you need. just gets confusing, trying to help 2 people in the same thread.

 

[johnsland8]

Re: 1993 Johnson 50 HP replacement options?

As for the 93 50, any 2 cylinder 50 from 1981 thru 2005 is the same powerhead. Either Evinrude or Johnson. A 2 cylinder 60 hp powerhead from 1980 thru 85 will work too. A 2 cylinder 55 hp commercial powerhead from 1980 thru 2000 will work also. Don't beat yourself up over the numbers, you'll never see the difference between your 50 and a 2 cylinder 60. There are some older powerheads that will fit but the internals are different and you may run into getting the wrong parts down the road.

In either case you can go to the Evinrude site and match parts to find the interchanging years. Start by comparing powerhead base gasket numbers.

Thanks Dhadley! That is very helpful info. I had been to the Evinrude website but I couldn't get it clear in my head what to check to see what would interchange. The powerhead base gasket is now obviously a good choice, but I didn't think of it earlier.

 

[johnsland8]

Re: 1993 Johnson 50 HP replacement options?

what makes you think you need a rebuild? what have you check other than compression? have you pulled the head to see if it has a bad head gasket. have you inspected the cylinders and piston?

Don't go tearing something down that could be an easy fix.

This is a very good point. I haven't checked it out at all yet. I was just going from the PO's description and an estimate from his shop/marina. It doesn't appear though that they did anything other than a compression check. I will pull the head and do an inspection first. I just occasionally see some screamin deals on c-list and a well known auction site for motors with a bad lower unit or other minor issues in which the powerhead could be had for very cheap. That's what prompted my question.

Thank you for the reply!

 

[tashasdaddy]

Re: 1993 Johnson 50 HP replacement options?

check it out, may just be a decarb and a $20.00 gasket. i really think i would do a decarb on it before anything.
Decarb, take a can of seafoam put 3/4 of it in the gas tank, with only 1 gallon of premixed gas. put the rest in a spray bottle. start the engine, and let it come up to temperature. then remove plugs, and them some real good shot of seafoam into the cylinders, replace plugs, let sit 15 minutes. restart, and spray the rest of the seafoam into the carbs, so the the motor almost stalls, wait and repeat until the seafoam is gone.then take for a wide open spin. then put in new plugs, ad premixed gas to the tank, and take it for a wide open throttle spin. it is going to smoke like a house on fire, during this process.

afterwards compression.recheck

 

[johnsland8]

Re: 1993 Johnson 50 HP replacement options?

check it out, may just be a decarb and a $20.00 gasket. i really think i would do a decarb on it before anything.
Decarb, take a can of seafoam put 3/4 of it in the gas tank, with only 1 gallon of premixed gas. put the rest in a spray bottle. start the engine, and let it come up to temperature. then remove plugs, and them some real good shot of seafoam into the cylinders, replace plugs, let sit 15 minutes. restart, and spray the rest of the seafoam into the carbs, so the the motor almost stalls, wait and repeat until the seafoam is gone.then take for a wide open spin. then put in new plugs, ad premixed gas to the tank, and take it for a wide open throttle spin. it is going to smoke like a house on fire, during this process.

afterwards compression.recheck

I'm finally getting a chance to work on it this weekend. I am going to do my own compression check first and then try the decarb and retest. I have two questions.. You recommend a gallon of premix gas. My motor is oil injected, do I still use a premix? And, I will not be able to do this in the water, can I effectively decarb it by running it out of the water? (w/ muffs or barrel, of course).

Thanks again!

 

[tashasdaddy]

Re: 1993 Johnson 50 HP replacement options?

if you are sure the oil side of the pump is working, just mix seafoam and gas.

muffs will do. but do not rev above 1500 rpms.

 

[johnsland8]

Re: 1993 Johnson 50 HP replacement options?

As for the 93 50, any 2 cylinder 50 from 1981 thru 2005 is the same powerhead. Either Evinrude or Johnson. A 2 cylinder 60 hp powerhead from 1980 thru 85 will work too. A 2 cylinder 55 hp commercial powerhead from 1980 thru 2000 will work also. Don't beat yourself up over the numbers, you'll never see the difference between your 50 and a 2 cylinder 60. There are some older powerheads that will fit but the internals are different and you may run into getting the wrong parts down the road.

OK... I did the decarb as suggested with no improvement in compression so I pulled the head and there was obvious damage to the cylinder walls.

I picked up an '89 50 HP Johnson with a bad lower unit for pretty cheap of c-list so I began the powerhead swap.

What I found is that this powerhead will not fit onto the drive shaft of my lower unit. My drive shaft is considerably larger than that of the '89. It appears from a quick look that the drive size and splines are an integral part of the crankshaft? Doing a quick part number comparison it appears that the '88 - '91 motors used the same crankshaft, '92 used a different crankshaft, and '93 used yet a different crankshaft. I have seen similar information like posted above about the interchangeability of numerous powerheads from different years, but how can that be if the drive shaft on the lower unit will not fit into the crankshaft splines? Hopefully I am just missing something obvious? What do I do now?

Thanks again for any help...