Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp)

1$Laketrout

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Hi
I have a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp) serial number 1741743 that the water pump has stopped working. I am having problems removing the lower unit. I followed the Seloc?s manual to put the motor in forward and removed the two screws that hold the lower unit on. The lower unit only drops about an inch and stops. I moved the shift to reverse and neutral without any effect. I removed the motor thinking that the drive shaft was stuck. I still cannot get the lower unit off. I think from the drawing that the shift rod attaches between the engine and the lower unit. The shift rod seems to be stuck. Am I missing something or do I have to get more aggressive to get the lower unit removed.
 

Texasmark

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

I had a 7.5 but never pulled the lower unit so I don't know but I have read threads on here where fishing sized Mercs have a shift linkage clamp under the carburetor that you have to remove to get it apart. If this is the problem, it will break apart about 1 inch but no more.

If you can't get it to separate at all, either you didn't get all the screws out or the drive shaft spline is stuck to the powerhead and I don't know how you break that apart without tearing something up.....but someone will jump in and guide you.

Mark
 

1$Laketrout

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

Hi

From the parts drawings the shift shaft is in two parts. The top starts at the shifter lever and then joins another section that goes to the lower unit. I cannot find an access area to get to the middle section. I think that if I take the top shifter apart the middle connector may get caught by the small opening at the lower unit.
I tried again to force the lower unit off without success. I used wooden wedges and tried penetrating oil. It is either stuck at the middle condition area or the shifter shaft is rusted onto the shaft. I have read most of the forums question and answers on lower units. They give very good information but for my motor it has not solved my problem.
 

Texasmark

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

I reread your original post and I got side tracked in my answer.

OMC used to use a 2 piece rod that had a clamp about midway down the midsection on the side of it, under an oval cover with 2 screws. This system was used in the '50's and early '60's for sure. Easier to see it on the '50's engines built before they started all their soundproofing shrouds that cover everything up. Their shifter operated in up and down fashion.

Your 1" drop down indicates that the shifter is the problem, not the driveshaft or overlooked screws or other things.

Doesn't make sense that you would have a 2 piece shift rod with no means of connecting, unless the top and bottom sections are held in place so that upon remateing the sections the pin and socket could find each other.....but there could exist such a thing. However, if this were the case you wouldn't be held up in a partial disengagement like you are.

I think you need to look up in the engine area at the end of the shift shaft. Push the lower unit back in place and pull out while looking there. Surely you will see what is stopping you from coming all the way out. I would assume there is a clamp around the shaft with a compression screw which probably has to be completely removed to get the clamp off.

Keep posted.

Mark
 

Texasmark

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

One more thing. You mentioned rusted shafts. I saw a 90 hp merc lower unit in the '65-'68 timeframe that had been removed for servicing at a dealer on the Gulf coast....salt water. The drive shaft was obviously made of carbon steel, not SS like OMC used at the time. I did not pay any attention to the shifter, but it too could be carbon steel. Anyway you absolutely would not believe the rust that had accumulated on that shaft. Later Merc went to SS and obviously for good reason.

So, you may in fact have a rusted shaft.

Keep bumping this post up to the top. Just submit a reply and say "Bump". That will keep it at the top of the list where it is visible and someone in the know will surely find it and be able to answer your question correctly.

Mark
 

1$Laketrout

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

Hi
I took the shifter apart and the shift shaft seems to be pressed into the shifter. There is no screw or clamp holding the shifter. I looked at the parts diagram again and the shifter seems to be in two parts and I cannot see any way to get to the area that the shaft may be attached. There is nothing holding the shifter just under the engine as some models do. Could it be that I have to remove the shifter housing? The housing is held by four metal and rubber parts. I have three other outboards and have removed the lower units without any problems.

David
 

Texasmark

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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

David, I don't know man. You would have thought that if anyone was out there that knew they would have seen this post as many times as we have hit it and bumped it back to the top.

Pull the cover you mentioned. Got nothing to loose.

Keep in touch,

Mark
 

luskateer

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May 1, 2008
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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

Hi,
I'm bumping this thread to the top. I have exactly the same problem with the same motor(3.9). I've removed the two nuts and the lower unit starts to come apart but seams to be hung up in the front. Is there more to removing the shift linkage that isn't obvious.
I'm thinking there's a screw on the outside that needs to be taken out. I think it retains a collar where the shaft separates. OR
is it just splined in place.
Any help
thanks
Rich
 

luskateer

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May 1, 2008
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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

I'll answer my own posting.
The shifter shaft is splined so all you do is simply remove it. There's nothing else that needs to be loosened. As long as you don't change the rotation of the shifting shaft it should reinstall easily. I left it in forward. The real bear turned out to be the impeller was frozen to the shaft. I took a drill bit with drill and went after it and was able to split it for removal.
How is that these one hour jobs turn into 5 hours......:(

BTW.....Please take this in the spirit in which it's given. I had a probem and was looking for help. I try to search past posts for answers. I can't help but notice that lots of postings don't seem to come to resolution. It would seem beneficial that if the original poster comes for answers and figures it out he should share that resolution with everyone........instead of just dropping the thread....I find it really frustrating to follow a thread for like 8 or 10 entrys and then it sort of goes away in the ether.......
enough said
still like this forum a bunch:D
 

bob1340

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Jun 12, 2010
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Re: Having problems removing lower unit of a 1965 Mercury Kiekhaefer Model 39 (3.9 Hp

I agree. I like when something gets resolved.
 
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