Outdrive Oil Vent Thread Broken

[babikov]

Hi,

I replaced gear lube in the outdrive unit (1993 Mercruiser) and tried to put back the vent screw (one on the left side). The manual said ?torque to 40 lb. ft.? I set the click wrench to 20 lb. ft. to be safe and, guess what, I broke the thread!!!

I did not push much, it was probably damaged before me, I just finished it?

So, the screw is stuck. It rotates, but does not go out. In fact, it seats there quite tightly, but I understand this is only a matter of time ? it will leak and fall out one day.

I don?t believe I broke the lower unit and have to replace it ?

Imagine I will get the screw out somehow, what can I do then to repair?

Can I simply glue the screw into the vent hole (and use the dipstick hole to vent in the future)? What kind of glue? Epoxy? Or, can I put another screw through the hole and put a nut on it from the inside (permanently)?

Thanks for your feedback.

 

[Bt Doctur]

Re: Outdrive Oil Vent Thread Broken

what type of drive? what kind of manual says 40Ft/Lbs, are you sure it wasnt inch/Lbs
vent is upper, drain /fill is the lower, your referring to???

 

[babikov]

Re: Outdrive Oil Vent Thread Broken

Checked the manual again. Indeed, inch pound, not foot pound. Stupid me..

Anyway, what can I do now?

This is the vent hole in the upper part on the left side (not the drain/fill at the bottom, not the dipstick hole on the top). The drive is Alpha One.

 

[Bt Doctur]

Re: Outdrive Oil Vent Thread Broken

Get the old plug out and try retapping for the original
Maybe retap for a slightly larger metric bolt
TIG the hole closed

 

[babikov]

Re: Outdrive Oil Vent Thread Broken

Thanks for your suggestions. I will try.

The first question is how to get the stuck bolt out?

It rotates there, without going out, and its head is level with the surface of the outdrive unit, so that there in no way to grip it.

I think about opening the top cover to reach bolt and push it from the incide(screwing it out at the same time). But I am not sure whether I will be able to reach the bolt, because I never opened the top cover and not quite sure what is inside.

So my question is, if I open the top cover, will I be able to reach and push the vent bolt from the incide (without taking the gears out, of cause)? Is this a good approach? And how easy it will be to put the top cover back? I checked the mannual and it looks like there is only one O-ring and a seal coat needed.

Or, is there completely different way to get that bolt out?

Thanks!

 

[nola mike]

Re: Outdrive Oil Vent Thread Broken

yes, you should be able to reach the back of the screw by removing the top cover. top cover's 4 bolts--THAT one is torqued to 20 ft lbs uses a standard 12 pt socket, no prob to put on. otherwise will need to drill it out.

 

[jtybt]

Re: Outdrive Oil Vent Thread Broken

Do you have a remote drive oil reservoir?

Sorry, I'm not immediately familiar with your set-up or the reservoir plumbing. If you have internal plumbing to the reservoir, you can just weld up the vent.

If you don't have a reservoir, put one in and weld an aluminum tube or fitting to accept a rubber hose to a reservoir.

Another possibility is to weld a thick pre threaded plate to the case. That's a pretty thin area to be drilling and tapping.

 

[babikov]

Re: Outdrive Oil Vent Thread Broken

Thanks for another suggestion.

There is no oil level reservoir on my model, but there is another hole with a dipstick, in the top cover of the outdrive. From what i understand, this second hole can be used for venting, the only inconvenience is that when pumping oil in, one has to check the oil level manually several times, rather then simply waiting when it starts comming out of the vent hole.

So, my plan is to close the vent hole permanently (somehow, by sealing, retapping or welding) and use the dipstick hole for venting in future.

It should work, correct?

 

[jtybt]

Re: Outdrive Oil Vent Thread Broken

Correct!

What drive is this you have?

 

[Fishermark]

Re: Outdrive Oil Vent Thread Broken

If you do decide to close up the hole, then I would suggest forget trying to remove the vent screw. Go ahead and seal it up using some epoxy, (JB Wled or Marine Tex), and be done with it.

 

[JustJason]

Re: Outdrive Oil Vent Thread Broken

How the ell did you even get it to torque to 20 FT lbs?? I would thing for sure the bit would slip right out.

 

[babikov]

Re: Outdrive Oil Vent Thread Broken

I will still try to get the old plug out for one reason. Any epoxy application requires oil free surface, and it is impossible to have with the old bolt in, with oil around its head, on the surface and in the thread. Furthermore, it seats there flat and there is no much space around to put in any apoxy or sealer.

So, when I get the bolt out, what best epoxy or sealer shoud I take to fix it there permanently. One of the above suggestions was JB Waterweld. Any other option?

And thanks for all your responses.

JustJason,

I had a goot bit, 1/2" flat.

 

[Fishermark]

Re: Outdrive Oil Vent Thread Broken

Not to beat a dead horse - but I still see no reason to remove the screw if your intent is to epoxy it. You could certainly clean it up well enough for an epoxy to stick. Use some brake cleaner spray (leaves no residue) and a rag and acetone.

 

[babikov]

Re: Outdrive Oil Vent Thread Broken

Jtybt,

I have Alpha One, serial number (on top of the transom assembly) is OF058634. Nothing on it says this is Gen 2, but the mannual I got for this serial number is #14 for Gen 2.

So, would it be better to use anepoxy like WaterWeld (downside is that requires oil free application) or a permanent thread lock (oil is fine, I guess).

Thanks.

 

[Fun Times]

Re: Outdrive Oil Vent Thread Broken

If you can or do get the old vent screw out, You might be able to use a (wurth timeserts) It's a Different type of helicoil, The people that use them seem to say it's a much better way to go then a helicoil.

http://www.timesert.com/

http://www.youtube.com/watch?v=uP2Up_hG7rc