Cracked case intake side. 84 25hp

[Eyeballsdeep]

Hey guys I'm up at the cottage and I was dialling in my idle speed when I hapened to notice gas bubbling from a crack in the case. I have a spare 1984 20hp. Would I be able to swap case halves or would it be easyer to change reed plates and carb etc. and do a power head swap. Just so we are clear one is a 25 the other is a 20. Both the same year. 1984. I still want the power of the 25. So should I just switch carbs or what's the difference. I'm bringing my family here for two weeks so if this thing will hold together. It's just a hairline crack. A novice person would never have noticed. But I still want this motor to run perfectly. Any suggestions would be apreatiat.

 

[Eyeballsdeep]

Re: Cracked case intake side. 84 25hp

I took a closer look at the 20 hp and the only difference I can see is the carb. The 20 has a nylon insert in the ventury and the 25 doesn't. So I think I'll just swap power heads and change the carbs

 

[boobie]

Re: Cracked case intake side. 84 25hp

Can you post a pic of where it's cracked ??

 

[Eyeballsdeep]

Re: Cracked case intake side. 84 25hp

It's cracked on the left side. On the intake side of the case. It's on the upper part of the crank. The crack starts where a bolt goes in through the reed plate intake. And it's almost right through to where the cases split. I was showing a friend what a great motor it is. And started it up with no cowl on it I saw gas running down the side of the engine. From the crack. It's in the area where the wires would hook up if it had electric start. It still runs great though. I have a spare 20hp. maybe I can find a case half some time but I'm on holidays and my wife wouldn't want me elbow deep in this thing. I wish I could post a pic but I'm using my phone and it won't let me for some reason.

 

[Eyeballsdeep]

Re: Cracked case intake side. 84 25hp


Sorry I guess I can post pics from my phone. I'll get one of the case soon. Thanks a lot. I can't see this as being a common problem but the only thing I could think what caused it is either over or under torquing the bolt. Or possibly a defective case half? I'm stumped

 

[AlTn]

Re: Cracked case intake side. 84 25hp

I believe those crankcases are line bored...if so it would be advisable to replace as a complete block assembly

 

[boobie]

Re: Cracked case intake side. 84 25hp

Correct as said above, line bored.

 

[Eyeballsdeep]

Re: Cracked case intake side. 84 25hp

Yah I guess rather than screwing around with that headache. Should I just swap carbs and lower units? It's a shame cause I just painted it shined it all up.
1984 johnson 25hp part 2 - YouTube
It's a shame cause it runs alright. I'll post some pics of the tear down and the crack. Why would this hapen though I don't understand.

 

[jasper60103]

Re: Cracked case intake side. 84 25hp

Looks like you did a great paint job...
1984 25hp johnson - YouTube

Is the crack in the gear case the only problem? Maybe it can be repaired?