Prove to me your a genius!

[francisj51224]

I have a '79 Johnson with a bad exhaust gasket. During disassembly, I found the drive shaft is seized into the crankshaft. I have been soaking it with PB Blaster, I have applied unknown lbs. of pressure to pull it free, and I have reluctantly applied heat to the end of the crank, nothing has worked. Are there any more suggestions?

 

[HighTrim]

Re: Prove to me your a genius!

oops, someone forgot the o ring at the top of the driveshaft!

Maybe try flipping it upside down so that gravity is working with you (but protected so that if it does free up you will not damage anything!) and dousing it with a mixture of ATF/Acetone. Although I have had good luck with PB BLaster as well, great stuff usually.

 

[AlTn]

Re: Prove to me your a genius!

as suggested, upside down, suspended , 1" or 2 "s would be enough with something besides concrete to break it's drop if it decides to, I'd recomment an air impact hammer with something between it and the driveshaft so you aren't directly virbating the d/s surface itself, keep working your way around the d/s with the vibration/impact, this may take several sessions if it works at all...keep soaking it between sessions...if and when it comes out the crank or d/s may be beyond service

 

[kfa4303]

Re: Prove to me your a genius!

Ok. The title of your thread, "Prove to me your a genius!", should actually read "Prove to me you are a genius!", or "Prove to me you're a genius!". Sorry, I couldn't resist :/ Ditto on the ATF (automatic transmission fluid) and Acetone. That seems to be the releasing agent of choice.

 

[raczekp1]

Re: Prove to me your a genius!

i would put powerhead on the latch with driveshaft pointing down,
grab drive shaft in strong vise grip tool,and start taping with hamer in this tool down to tap just straight down

 

[daselbee]

Re: Prove to me your a genius!

Take it or leave it....

Drive wedges into the gap between LU and ex housing. Go in from rear, and use just enough wedge to create a stress up there on the DS to crankshaft joint. Kinda wedge it so as to bend the DS slightly.

Now...start the motor. The vibration of running it, combined with the stress on the DS/crankshaft joint will break it free.

Be prepared to shut it off, and be prepared to control the drop of the LU when it breaks free.

Controversial? Yep. That is what I am all about...

 

[JB]

Re: Prove to me your a genius!

Model number??

 

[F_R]

Re: Prove to me your a genius!

I have a '79 Johnson with a bad exhaust gasket. During disassembly, I found the drive shaft is seized into the crankshaft. I have been soaking it with PB Blaster, I have applied unknown lbs. of pressure to pull it free, and I have reluctantly applied heat to the end of the crank, nothing has worked. Are there any more suggestions?

Assuming it is the 35hp you asked about earlier. If you applied heat to the crank, you obviously have the powerhead (and drive shaft) removed, right? If the usual soaking and vibration won't get it out, you will have to get more serious. Either you or somebody equipped, make a clamp to fit the shaft. Forget the vise grips, it will just cut grooves in the shaft. Then you will need a heavy piece of steel with a hole drilled through the center to slide on the shaft (AKA a slide hammer). Then beat the shaft out of the crank by sliding the hammer against the clamp. Do it in an area that won't be harmed by the brutality.

If you got that crank very hot, replace the seal.

 

[Faztbullet]

Re: Prove to me your a genius!

Usually in my experiences with this problem, when you get it removed the crank splines are badly damaged and the crankshaft needs to be replaced....my humble $.02

 

[1946Zephyr]

Re: Prove to me your a genius!

I must have been really lucky with outboards in the last 20 years or something. I am yet to see this form of catastrophy.

 

[F_R]

Re: Prove to me your a genius!

1946, You really must be lucky. Or the mechanics in your area have enough sense to use a new o-ring on the splines. And you must not have worked on many Elgins & Chryslers etc. Yes, some Mercs too.

 

[1946Zephyr]

Re: Prove to me your a genius!

True, I haven't seen many Elgins and Chryslers. Worked on only a handful of Mercs. Now I know what to stay away from.

 

[HighTrim]

Re: Prove to me your a genius!

I have only seen one, and the motor cannot be blamed. The previous owner did not think the o ring was necessary.

People dont realize how easily water "climbs" the drive shaft while spinning over 4000 RPMS.

 

[wilde1j]

Re: Prove to me your a genius!

I'll bet he's (1946) a fresh water guy!

 

[1946Zephyr]

Re: Prove to me your a genius!

Well, I do live a couple hours from the coast, but I have seen a few. Some are so bad, that the bolts pretty much become a permanent part of the motor.

 

[sschefer]

Re: Prove to me your a genius!

Haven't seen Francis (OP) respond yet but I'm a little confused being a Merc guy. How is it that he was able to heat the crankshaft if the mid won't separate from the powerhead. Do these motors have a drive shaft that will allow the lower unit/mid to be removed without removing the drive shaft too? Like I said, I know nothing about JohnnyRudes but if it were a Merc, you'd have to tear down the L/U.

To the OP if I'm totally messed up and you can get to the drive shaft and all the PB blaster soaking hasn't worked then you'll need to break out the sawzall and cut the drive shaft. If you're careful you can cut and have it repaired provided you can get the splined end out of the crank otherwise, a new crank will be needed as was mentioned before. I had 1 Merc 2.5L that did this to me and that ended up being the solution for me. I hated to do it but it was the right decision in the end. I never did get that piece out of that crank. I kind of half arsed expected it to fall out as soon as I cut the drive shaft and was actually happy that it didn't.

 

[F_R]

Re: Prove to me your a genius!

I believe he said in another thread that the shaft pulled out of the lower unit. The only thing normally preventing it from pulling out is the water pump drive key won't go through the pump housing....unless you brutally force it. But y're right, it ain't a Merc.

 

[kodibass]

Re: Prove to me your a genius!

Here is what I have done on 2 very stuck shafts & it worked, I clamped the rag wrapped shaft in my wilton 5" vise, I put 2 small hydrolic bottle jacks under the powerhead with 2 pieces of 1/2 flat plate between jacks and powerhead bottom, "slowly"-"evenly" applied upward pressure on the jacks, This is kinda hard to write/explain but I hope you get the basic idea, I did not care about either of these engines as they were junkers, one was 15 rude, and one was a clinton (wards 7.5) I still have both, & both are still junk. But them shafts is out!