lower unit mounting bolt stuck and stripped, help!!

[f4igrad]

Re: lower unit mounting bolt stuck and stripped, help!!

i have second guessed myself on this, but i removed the bolt where the shift rod connects, i removed the trim fin and the bolt underneath it, and i removed the bolt directly in front of the trim fin. i have been following the service manual precisely, and i have retraced my steps just to make sure. If there were several bolts left, I wouldn't be able to twist the lower unit so much. it will twist back and forth by almost half an inch, but i cannot even fit a hair in between the lower unit and upper unit in the area of the seized bolt. it is stuck and stuck good. i have heated the thing up so many times that i can't imagine the heat doing anymore good. i probably put the torch on it 10 - 12 times today. i have pulled and wiggled the engine so much that the entire boat wiggles, in fact i have put so much weight on the lower unit when trying to break it free that the front of the trailer would leave the ground. it is absolutely ridiculous how seized this bolt is. if i didn't know any better, i would swear the bolt was welded in place.

 

[imported_lorin]

Re: lower unit mounting bolt stuck and stripped, help!!

One or two days spent on a motor is not such a big deal although I understand your frustration. Maybe try this. Remove motor from boat. Remove engine cover from motor. Stand engine up-upside down so that it is sitting on the flywheel. That way, when you spray penetrating oil, it will run down into hole. This next part is real important.Try to get your hands on an oxy-acetylene torch. Oxy-acetylene is much more effective than propane for unsticking bolts. Propane isn't hot enough to take advantage of the difference in expansion rates between the steel bolt and aluminum housing. Oxy-acet. makes a big difference. Another thing you could try is drilling a small hole through the non-threaded part of the housing till you reach the bolt. Then you would have an even more effective area for squirting in oil. You dont want to break the bolt because you'll need as much of it as possible to grab onto when the gearcase does come off. Don't despair.

 

[itstippy]

Re: lower unit mounting bolt stuck and stripped, help!!

What do you guys suppose is flexing when he twists the LU a half inch? That's interesting. It HAS to be putting great pressure on the stubborn bolt, doesn't it? Can you devise a way to hold the thing in the "flexed" position overnight?

 

[Walker]

Re: lower unit mounting bolt stuck and stripped, help!!

I think the shank of the bolt is corroded in the collar of the lower unit but the threaded part is free in the midsection.

 

[f4igrad]

Re: lower unit mounting bolt stuck and stripped, help!!

well, i am taking it to someone with vast more knowledge than myself on saturday. i will report back if we get it unstuck, and how we do it. i tried hammering more wedges today and it hasn't budged.

 

[xtraham]

Re: lower unit mounting bolt stuck and stripped, help!!

if there is any way at all to get some coke-a-cola in it and keep it wet it will come out I have laid a rag full of coke on simular bolts over night, works for me..good luck

 

[toddr5516]

Re: lower unit mounting bolt stuck and stripped, help!!

i believe you may still have a little burr of the bolt hanging off keeping the LU from dropping if not then possibly use a metal scraper to wedge in the area of the bolt that is stuck.

 

[imported_IL_Glastron]

Re: lower unit mounting bolt stuck and stripped, help!!

I know you have tried it all, and i know how frustrating this is!!

Just do you have the screw OUT 100% for the shift shaft? I once did it and just backed it out enough where I thought It would be enough, but it wasn't and I had the same issue you did.. The unit will drop juuust enough to tease you! Make sure that shaft is not hanging onto anything under there.

Just a thought. Best of luck!

 

[f4igrad]

Re: lower unit mounting bolt stuck and stripped, help!!

well, just wanted to update this thread.

i trailered the boat 175 miles down to this guy's house yesterday. got there at 9:00 and we started working at 9:30. It took a solid 2 hours to get the lower unit off. we tried everything and ended up having to use screwdrivers to pry it and hammer a block of wood to get it to let go. took FOREVER, and there were four of us working on it (myself, the guy and his two sons). We were able to remove what was left of the old bolts and I had bought a whole new set to replace them with. there were many many more corroded bolts that slowed us down, and one snapped off and had to be drilled out. we finally got in and replaced the clutch dog and forward gear (he thought they looked pretty good, and just by looking at them the wear looked minimal. he was thinking that my prop was bad and that was the thunk i was getting). While we had it apart, we cleaned everyting very well, changed all of the oil seals, changed the impeller, and replaced a lot of the bolts. it kept storming on us as well, so that slowed us down. we put it all back together and I left his house at 7:30 to head home. after 10 hours worth of work, he only was going to charge me $50!!!! That was insande to me, so I gave him $200 and told him to take his sons out to dinner and a movie. Trailered the boat back home through some awful storms and got in late.

Took the boat out today and it shifts like butter, it is so smooth you can't even hear it go into gear. Ran it up to 5000 rpms and the boat was hauling some @ss, still had some throttle left but I didn't want to go much faster. The boat is an entirely different animal once it planes and gets up to speed. Much more fun considering the lake i am on is huge and has a lot of things to explore.

Thanks for all of your help through this, i am thrilled that the boat runs fast and strong now.

 

[tmcalavy]

Re: lower unit mounting bolt stuck and stripped, help!!

Well Neptune has tested you and passed with flying colors...now you have a real war story to tell, hang on to that boat and make some memories with it.

 

[rickdb1boat]

Re: lower unit mounting bolt stuck and stripped, help!!

Good to hear F4! Glad you got it taken care of and in the future, drop the lower unit every other year and replace the pump. Good practice to follow and it will be much easier to get those bolts out....Enjoy the ride...

 

[bluediamond46]

Re: lower unit mounting bolt stuck and stripped, help!!

Hammer the wedges in there as tight as you can get them and let it sit overnight. Then tighten them up again tomorrow...And continue to do this until it falls..It may be that the driveshaft is frozen in the powerhead..Give it time...

 

[bluediamond46]

Re: lower unit mounting bolt stuck and stripped, help!!

i have the same motor, i also had the same problem but finally realized the shift rod had to be removed if it is a remote control unit, if it is, then you have to remove the starter to get to the shift connector, after the bolt is removed from the shift housing, unit will drop so brace it up or hold on to it.