Late 80s 70hp Evinrude driveshaft.

[bonz_d]

I will be picking up a used boat this weekend that has a late 80s Evinrude 70hp VRO that has a major issue. When this engine was taken in this past spring for service and a water pump change it was founf that the drive shft had siezed into the crankshaft. The shop was unable to get it apart or the owner was unwilling to pay to have it fixed. So there it is unrepaired, still on the boat.

The purchase price is reflective of the nonrunning engine so basically buying the boat and trailer.

Question is this engine even worth fooling with? Has anyone been able to get one freed up? Would the powerhead need to be removed to fix this? Can the powerhead be removed with the shaft attached?

If it's not worth fooling with then I'll just remove and replace it.

Thanks!

 

[Fleetwin]

Re: Late 80s 70hp Evinrude driveshaft.

They can be freed up-SOMETIMES.

I've had a couple seized shafts on smaller engines.

What I did was spray plenty of PB Blaster into the exhaust housing with the engine hanging upside down-bolts loose but still in place. One of them took almost two weeks but it eventually came free.

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

I'm more than willing to give anything a try. If it works the engine would be basically free.

 

[oldman570]

Re: Late 80s 70hp Evinrude driveshaft.

The upside down trick will work for most motors with a little patance at times. I've had to drill a small hole in the midsection inline with the DS inorder to spray the PB Blaster in on the DS and let it run down it to the crank connection. Then taped and used a SS screw to close the hole after getting the LU off. It can be welded shut also. I would run a compression test first along with checking the spark to see if it is worth the trouble to repair. The impeller must be bad and should be replaced so spining the motor over for testing should not hurt any. JMO
Oldman570

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Well the boat was brought home Saturday and I not sure how I want to proceed.

The shaft is really siezed in there and when they tried to remove it they must have stuck pry bars into it and really reefed on it as the exhaust housing has 2 large cracks in it. Also there is not enough seperation between the lower unit and exhaust to try and spray down the dive shaft.

So, do I just junk/scrap/salvage what I can? Do I try and repair it? As-is it is useless.

I have thought about removing it and as the exhaust housing is already trashed just taking a saws-all to the exhaust housing and cutting it off to get access to the shaft and then trying to remove the shaft. Then if sucsessful just looking for a donor motor to cannablize parts from.

I believe the engine it self is functional as while cleaning out the boat I found a brand new in the box water pump kit and I don't believe they would have purchased it if the motor was not running.

Opinions and thoughts please! BTW thisengine is equiped with PTT.

 

[mark1961]

Re: Late 80s 70hp Evinrude driveshaft.

The cracks in the exhaust housing may be able to be repaired (welded).....the suggestion above from oldman re driliing an access hole so you can get some pb blaster to run down the shaft might be worth a shot.

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Doubt it. It's also all distorted from them trying to remove and the one side has a large gap were it is cracked.

 

[oldman570]

Re: Late 80s 70hp Evinrude driveshaft.

Check PM's
Oldman570

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Guess no one has an opinion for a change.

 

[phillnjack2]

Re: Late 80s 70hp Evinrude driveshaft.

my friends 50 hp has the same problem.
his engine is an 87 50hp and no way is it comming apart.
ive tried everything, even managing to hang it upside down and using a slide hammer.
tried filling it up with diesel and leaving for a week etc, and still nothing.

best option is to get rid of it for parts, or buy another engine and keep it for spares.
by the time youve got it off (if you ever do) the gearbox bearings will be shot,possibly bent shaft
gearbox housing needing welding or a replacement housing the list goes on.

if you knew the engine was a realy good strong motor that was reliable etc , it then could be worth it.

But to be honest i dont think youl have much luck if a dealer has already tried to free it.

by the way you cannot get powerhead off unless you free the drive shaft , thats without cutting through it ofcourse.


phill

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Well I was told that it was taken to a shop but I don't think a shop would have done this! Do you? There are tool marks on both sides of the exhaust housing. Also haven't tried to turn it over with the lower hanging like this to get a compression check. Though I still don't believe they would have spent the money and effort on a non-running engine.

 

[James R]

Re: Late 80s 70hp Evinrude driveshaft.

It may be possible to have the casing welded. However if you want to save the lower unit and the powerhead take a tank cutter to the leg to access the drive shaft with a sawzall. Cut the shaft and separate the lower. The powerhead can then be removed. With the powerhead off it may be possible to remove the remaining shaft with heat applied to the shaft. If that does not work then stripping the powerhead to separate the crankshaft for better access may work.
As was stated you need to do a compression test and spark test to get some idea of the motors worth. If you have both of these tests prove good then it may be worth the work.

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Thanks James R,

When I bought the boat it was with the assumption that the motor was trash and even told that to the seller. Have already looked at 3 replacement engines for the boat. 50 to 75hp outboards are pretty plentifull in my area so a replacement isn't an issue other than finding the right one.

The thinking on this engine is if it's junk then whatever is salvable will be removed. So far I've been unable to do any testing with this still lose. So yes at this point I don't know what I have here. Which is why I've thought about getting the lower unit free then I can check compression and spark and determine if it's worth proceeding. Then if the powerhead is good and strong then I don't have a problem with spending a few hundred bucks to repair it. Again I am pretty certain that I could find a blown one pretty cheap to cannablize.

 

[mark1961]

Re: Late 80s 70hp Evinrude driveshaft.

Wow! They really tried to lever that sucker off! Is the shift rod disconnected? Lol!

You should give oldmans tip a shot......what have you got to lose if it doesnt work?

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Wow! They really tried to lever that sucker off! Is the shift rod disconnected? Lol!

Yes they did, didn't they! You know I was thinking the same thing about the shift rod but as of yet I haven't been able to look. Will do it this weekend and hopefully get it removed from the boat at the same time.

 

[fishfeatures]

Re: Late 80s 70hp Evinrude driveshaft.

Wow! They really tried to lever that sucker off! Is the shift rod disconnected? Lol!

You should give oldmans tip a shot......what have you got to lose if it doesnt work?

this was my guess too, is the shift rod beneath the bottom carb disconnected? this i reckon would cause the gap, and unfortunately the damage caused in trying to remove the lower unit

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

this was my guess too, is the shift rod beneath the bottom carb disconnected? this i reckon would cause the gap, and unfortunately the the that you caused in trying to remove the lower unit

Couldn't quite interpet this last part but as of right now I cannot answer as to the shift rod. I will know more today now that I have a bit of free time to investigate. To be clear this engine was purchased in this condition as not running.

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Just went out and looked and yes the shift rod is disconnected.

Time to think this out.

 

[bonz_d]

Re: Late 80s 70hp Evinrude driveshaft.

Sorry to bring this up but I haven't given up yet.

Warmed up enough to go out into the garage and putz with it a bit. I have the engine turned upside down at the moment and while looking I found a spot where there is access to the driveshaft and the end of the crank. I've got it sitting on soak cycle right now with some good penetrant oil. It is also currently not in gear so the prop shaft spins freely.

I'll give it a couple days to soak and then see if it will come lose. Think it would help if I was able to get it into gear and try and turn the prop shaft back and forth?