1975 15HP Johnson transom clamps froze up, how can I free up.

Boatist

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I have a 1975 Johnson 15 HP 2 stroke motor that I can not get loose from the kicker lift bracker. The 2 transom bolts are froze up and will not turn.
I have not forced them as do not want to break.

Last year I did not take off as normal as the combo lock I had on it was froze up from salt water. This year I cut the old lock off. Now I want to get the motor off but the transom clamp bolts will not turn. I tried some liquid wrench today but has not loosened up so far. The bolts to not appear rusted or salt corroded but they sure are stuck. I also tried some heat from a propane tourch but no help.

I do not think WD 40 will work.

Anyone have any ideas???
 

tashasdaddy

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

try some PB Blaster. keep applying, every couple of hours. try to get a wrench on the shaft, as the handles are weak. you might tap on the end on the bolt, to loosen oxidation.
 

5150abf

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

If I have this correctly you are talking about the bolts through the transom that hold the motor to the boat, those are easily replacable.
You have gone through my bag of tricks, if heat and penatrating oil don't get it you almost have to break them.
I geuss I don't understand why you don't want to break them, I would just start torqueing them and it either it comes off or they twist off, either way you get the motor off.
Worst case you have to get $5 worth of bolts.
Maybe I don't understand.
 

wavrider

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Like Tasshadaddy's said PB Blaster works miracles.
I read on one post here in the forum that a mixture of transmission fluid and acetome works better than anything else, do not know the ratio of the mixture but I do know it will play heck on the paint and finish so if you try this combo be careful of your transom paint and engine paint.
 

tashasdaddy

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

5150abf, this is a 15hp motor, it is not thru bolted. it used the transom clamp bolts. like these.
5515hp-1.jpg
 

5150abf

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

That would explain his reluctance to break them, had a 10 horse like that.
Maybe try tapping them lightly with a hammer. the vibration might break it lose.
Or get one of those computer cleaner air cans and blast it with really cold air.
 

tashasdaddy

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

it is a very common problem, on those used a trollers, expecially in salt water.
 

mattyv

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

this happened to me on my 25, i used PB blaster often and ended up getting them out with a pair of vice grips, no heat. totally wrecked the bolts and new ones are around 60$. at least from the dealer
 

ezeke

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

I have had a little luck using smaller visegrips on the transom end of those. Using penetrating oil, the handle and the vice grips got them loose. Heat may do it too, but that can get messy.

I've been using permatex anti-seize on those for a while now, and mine have not seized up again. The zinc anodes help, too.
 

kenmyfam

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Keep using the penetrating fluids every couple of hours and try tightening a little and loosening a little. If you get any movement either way then you are 90% there. Do not rush things if you get any movement, keep tightening and loosening a bit at a time while applying more penetrating fluid. You can also put a short pipe over the toggles to encourage things a bit but be very careful as a pipe will multiply the force you are exerting.
Good luck and be patient.
 

nightstalker

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

I use brake fluid to loosen up rusted nuts/bolts. Put it on liberally, let it sit overnight, reapply every 12 hours or so. After a couple of days, it will do the trick.
Nightstalker
 

samo_ott

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

This sounds exactly like the "how to free a stuck piston" thread :) everyone has a different tried and true method :)

I would heat with the propane and then when hot, hit it with the pb blaster, as the theory is there's more space in there for the goop to get in when the metal is hot and expanded... See! My 2c worth also :)
 

Boatist

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Thanks Everyone for the ideas.
As TD picture shows it is that type of clamp.

I have herd of PB Blaster here on IBoats but have never seen it in a store. Is it something only found in the east? What store carries PB Blaster?

I did a search here on Iboats, Cabela's, Bass Pro's, Champion Trailers but no hits.
 

iwombat

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Just about every Napa and Shucks here in the NW carries PB blaster. There are many other recepies for penetrating oils. My personal favorite is diesel and ATF. You might be able to get a better set of tools applied to the problem by drilling out the rivets that hold the handles on and using big wrench on the square end of the bolt.
 

kenmyfam

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Just about every Napa and Shucks here in the NW carries PB blaster. There are many other recepies for penetrating oils. My personal favorite is diesel and ATF. You might be able to get a better set of tools applied to the problem by drilling out the rivets that hold the handles on and using big wrench on the square end of the bolt.

Very wise idea !!!!
 

Boatist

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

Thanks for the help and Ideas
I found PB Blaster at Walmart and every day during last week I gave it a shot and tried the bolts with the Handles but did not budge. Today I got out all the tools and went to work. First side put on a pair of vice grips and rocked it back and fourth and starting moving right away.

Second side tried the same thing but not so lucky. After trying the vice grips for a while the top and bottom of the threads tore up pretty good right near the handle on the end. I Found a 1/2 inch wrench allmost fit on the shaft so I took a file and filed the thread down a little more and got the 1/2 inch wrench started. Hammered it all the way on and use it and got broke loose.

After broke loose on both sides tried PB Blaster again bit did not seem to help.
Next tried some Silicone Spray and I could turn with a single finger. The bolts had been coated with antiseize in past years.

The real story is do not skip even the simple maintenance like I did last year because a combination lock was froze up from salt water. I should have cut off last year took the motor off and cleaned up and varnished the homemade mounting board. I will complete all my maintenance this year before heading to the ocean.

Anyway wanted to say thanks for all your ideas.

One last question what is best for decarb. DEEP CREEP, SEAFOAM or OMC ENGINE TURNER.
 

samo_ott

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Re: 1975 15HP Johnson transom clamps froze up, how can I free up.

That's good you got it. Salt water kills things.

DEEP CREEP and SEAFOAM are the same thing. DC is an aerosol and SF is a liquid. SF is for squirting in the carbs for fogging and DC goes in the tank for decarbing and maintenance. I use em both. They do other stuff also. Read the label. Have not used the OMC stuff though.
 
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