bravo gimbal bolt stripped - need advise
 

one ot the two horizontal gimbal bolts is stripped on my outdrive. it is one of the two bolts that define the trim pivot axis. the bolts cost $15 each and i lost two in two weekends!!

the outdrive casting threads are stripped. I am taking the bolt in to get a helicoil kit. does that make the most sense?

If I trim the unit up a little and take the other bolt out, can i rock the outdrive out along the drive spline pivoting about the hyd cylinders to reveal the hole i will need to tap and install the helicoil?

otherwise i will have to try to drill and tap through the clearance hole on the gimbal housing. I don't really want to take the whole drive off. I am out of town for two days and need it ready to watch the smoke on the water poker run!!!!

any suggestions would be great!!

Stripped bolt's
 

It's actually an easy repair, I just fixed one for a buddy last week.

That bell housing is easy to remove, looks intimidating but its not. Remove the six bolts
holding your drive on. Next the two bolt's you
stripped. behind the bell housing is a clamp
for your bellow's and for your oil line. Also your shifter cable.

Your threads need to be ground out super clean.
And taken to a Good welder. A tig welder will
get you the best work. Redrill and tap it's a
5/16 - 18 tap. If you didn't already know
it needs to be loctited. ( RED ) otherwise you
will continue to repeat this process.

Otherwise a new bell housing is $300 - $ 400.

Good luck
Cougarman

COUGARMAN is right -Drill out ALL the old damaged metal and have a GOOD welder fill the hole. Just a hint before you do anything take a scribe and mark an X over the existing hole so that you will be able to properly center the new hole. Fill the hole with new metal and then have a machine shop redrill and tap it for you to make sure it is perfectly straight. Helicoil will not work.

I used a heli coil earlier in the year and it worked great. If you do a search on this topic you will be able to read all the help I got.

BT :cool:

Heli coils
 

I haven't used heli coils myself, my only concern
is if they are steel or stainless steel.

If they are steel it will rust away in raw water.
And second, steel and aluminum don't get along.
They react against each other and cause a powdery
type corrosion.

Also you would need to special order fine
thread heli coils.

Back to Tinkerboaters comment, he is right about
marking the center. There is a couple way's to do
it.
First eyeball center and scribe it as Tinkerboater said.
Second that round pad is pretty accurate, so you can measure center of that and not be to far off.

Third drop it off at a Tool & Die shop and have
them do your welding, machine it back flat, and drill and tap it. Tell them the holes need to be
the symmetrical side for side.

I work in Tool shop so I'm furtunate to have
all the machinery at hand. I took machine
cordinates before I started. In the machine
world thay would be ( X, Y, & Z ) cordinates.
I won't go into all that detail, but if you choose
to take it to a true Tooling shop they will
know what you are talking about.

Best of luck

Cougarman

thanks

just got back into town, the helicoil is in 5/16 x 18.

good point about IT not being stainless. hmmmmmmmmm, didn't even think to spec it, was in a hurry

but, mating a stainless helicoil to the alum outdrive i don't think is any different than the bolt mating to the outdrive. I think I will put antiseize on and locktite????????? is that counter productive? the antiseize will put a bearier between the disimilar metals.

now i am wondering about re welding/ etc but I want to be boating this sat to watch the smoke on the water

I guess if I can get a stainless helicoil, it should be no different an interface than the original bolt. I'm stopping into the industrial shop tomorrow to get the kit. I'll ask about the helicoil material.


I'll search about the helicoil
thanks for the advice

Hey Rob, we should really take this issue to our welder buddy in Port Sheldon. He is a GREAT welder. If we bring him the parts, he will do it for free too. How about that price???

You know who I'm talking about don't you? Russ Six. Shop on the dunes? Ring a bell??

Maybe we can do this on Friday after work next week. Then I'll crash at your house and leave for the race with you from there???

Oh and yes, anti-sieze and loctite are counterproductive!! And you call yourself an engineer. Sheesh!!!!!!!!:rolleyes: :rolleyes: :rolleyes:

Yea what MIKE said -- You can't use locktite and anti-sieze on the same bolt. That bolt is under a LOT of force -- Use the heli coil for temporary to get the boat on the water then next week fix it properly. ( Weld the hole and retap )

if the helicoil is stainless, I feel that is a good fix. if I weld, then I will have to paint too.

do you think I can drill and tap by hand with the drive on the boat? otherwise, Mike whatcha doing tonight? i have never taken off an outdrive.

good idea about seeing Russ though. If I get help taking the outdrive off, I will get it welded, otherwise i will tackle the helicoil myself I guess. There i made a decision:D

It would be hard to hold the drive exactly on center while you drill and tap the bell housing, I would opt to remove the drive then you could re-grease the U joints too. If the bell housing is off center you may damage the bearing race with the drill or tap. The bearing surface is made only out of some nylon plastic. It would be best to remove the bell housing and work on it on a bench but depending on wether you have the exhaust bellows or not it may be more work to take it off than what it is worth. P.S the hinge pin is torqued to 145Ft Lbs and red locktited in.