Removing rusted bolts HELP!!!

[100333624]

So I got my powerhead off and now I am stuck... What you are looking at is right below the powerhead on the main part of the engine, where the lower unit driveshaft sticks up about 2 or 3 inches, there are 2 bolts that I have to remove in order to get to the swivel bracket assembly that I'm trying to fix. The problem is these 2 bolts are rusted and have managed to bond themselves onto the engine casing. Steel bonding to aluminum?! I am not sure whats going on here but there is some water in the pockets there, you should be able to see them in the pictures.. But now what do I do? How do I remove these bolts without casing catastrophe to the engine casing? I could get new bolts but how do I get these ones out? They don't even budge and I don't wanna resort to grinding in such a tiny space... PLEASE give me some helpful ideas!!

Thanks,
Nick

 

[jimbo_jwc]

Re: Removing rusted bolts HELP!!!

Aerokroil penetrating oil ,leave on a day and reapply let it soak , apply heat next day with another soaking while warm . Use right six point socket weather American or metric shim stock over top of bolt and drive on so tight and hammer impact .

 

[Moody Blue]

Re: Removing rusted bolts HELP!!!

Aerokroil penetrating oil ,leave on a day and reapply let it soak , apply heat next day with another soaking while warm . Use right six point socket weather American or metric shim stock over top of bolt and drive on so tight and hammer impact .

In addition to the advice above, keep in mind that it will not come out easily (maybe not at all) and you need to be very patient. Try to achieve SMALL movements in the bolt, both loosening and tightening. Repeated application of heat, penetrating oil (I prefer PB Blaster) and shock/vibration will help to break it loose. I've spent days working on seized bolts like this to get them out without breaking.

You can try applying a sharp hammer blow directly onto the head of the bolt to jarr it loose.

Is there a nut behind or is the bolt threaded into a blind hole?

So you decided to keep the 78 80hp?

 

[gm280]

Re: Removing rusted bolts HELP!!!

Some good advice above in my opinion. I'd also go carefully while using their advice. AND once you do get them out (and I know you will) go back with stainless steel after you retap the holes. Those rusted bolts are in a tuff area to get to. I second the six point socket and the shim material if the socket is too loose... Is there any chance to get a vice grip wrench on the side of the bolt. With the penetrating fluid and some heat, the vice grip will maybe help break them loose. Odd how such corroded bolts and nuts seem to always be in hard areas to get to...? Keep us informed and more pictures too...

 

[mercurymang]

Re: Removing rusted bolts HELP!!!

If you absolutely have to get them off there is a fairly good trick. First, soak it as long as you can with some pbblaster (there are actually some better things to use but I don't know all their names). Next, get a 1/2" impact and put it on the lowest possible setting. Then just pound away at it. I would recommend going forward and backward initially. Thats what I did to get the bolts out of my block in the pic i posted up. In the end, I did end up breaking 3 off but I think that if I had been more patient, it would have worked.

 

[100333624]

Re: Removing rusted bolts HELP!!!

In addition to the advice above, keep in mind that it will not come out easily (maybe not at all) and you need to be very patient. Try to achieve SMALL movements in the bolt, both loosening and tightening. Repeated application of heat, penetrating oil (I prefer PB Blaster) and shock/vibration will help to break it loose. I've spent days working on seized bolts like this to get them out without breaking.

You can try applying a sharp hammer blow directly onto the head of the bolt to jarr it loose.

Is there a nut behind or is the bolt threaded into a blind hole?

So you decided to keep the 78 80hp?

Moody Blue yes I figured it would be best to keep the 80 for now, do what I will with it and I can learn a lot from it before moving onto a bigger badder brother of his...

I've tried hitting it, and even cleaning out everything around it but it is literally welded onto the casing and I don't think it can come out unless I grind it off... The problem with that is its such a tiny space I don't know how I can grind in there..

That's one other issue now, I don't know if it threads into this piece or the piece below it, although I have a feeling it just threads into the piece below it...

 

[100333624]

Re: Removing rusted bolts HELP!!!

I will do my best, I will try the penetration method with PB Blaster as I have a spray can left over from last year, along with propane heat (not strong enough?) and maybe vice grip twisting methods lol... It's unfortunate that half the head of one of the bolts has corroded away and trying to use sockets on it is almost impossible... the other one however fits a socket on it just nicely!

 

[gm280]

Re: Removing rusted bolts HELP!!!

Instead of grinding the heads off, you also have the option to drill it out. Start with a smaller size drill bit and work your way up until you get to the threads. Then you could take a punch and hammer and maybe collapse the sides in and remove the two parts. After you are able to do that, you should be able to get a vice grip on the remaining part to see if it will turn out. If you still can't get it out, then drill for a tap the correct size and retap the holes cleaning out any remaining material... Yes it is a long tedious effort but it does work in the long run...been there, done that...

 

[100333624]

Re: Removing rusted bolts HELP!!!

Instead of grinding the heads off, you also have the option to drill it out. Start with a smaller size drill bit and work your way up until you get to the threads. Then you could take a punch and hammer and maybe collapse the sides in and remove the two parts. After you are able to do that, you should be able to get a vice grip on the remaining part to see if it will turn out. If you still can't get it out, then drill for a tap the correct size and retap the holes cleaning out any remaining material... Yes it is a long tedious effort but it does work in the long run...been there, done that...

You know what, that's exactly what I'm gonna do! After checking it again it is clear that it has bonded to the exhaust extension plate casing, I can clearly see fresh metal under the rust and it's solid as ever! No way any penetrating liquid will get in there because it's WELDED itself on all around! It only makes sense that these 2" bolts screw in at the extension plate below. At least that what the diagram says.. Then the plate underneath this one has 7 bolts that screw into the drive shaft housing below it! So I'm on a drill them out since I can't grind! Thanks guys!

 

[reynold460]

Re: Removing rusted bolts HELP!!!

i had a 115 merc with this problem and thats what i did drilled the tops off the bolts lifted the spacer off the bolts , took a pair of vicegrips to the remaining bolt shaft sticking up and removed them

 

[100333624]

Re: Removing rusted bolts HELP!!!

Awesome, I haven't done anything as of yet and I will drill them out right now... I am concerned now, why did this happen in the first place? Some sort of leaking gasket? How did water get in there to begin with??

 

[100333624]

Re: Removing rusted bolts HELP!!!

Ok so I got the bolt heads off! Thanks for the drilling tip it worked great! But the part doesn't come off? Could those bolts be threaded all the way? Or how can I get the gasket to separate because maybe that's holding it down??

 

[TD_Maker]

Re: Removing rusted bolts HELP!!!

Try to get a set of reverse thread drill bits. Sometimes, the bit will grab the screw and back it out.

 

[Mi duckdown]

Re: Removing rusted bolts HELP!!!

Big fan of reverse drill bits as TD posted. not to be a smart arse but the drill has to be in reverse also.

 

[100333624]

Re: Removing rusted bolts HELP!!!

Ok so I removed them now and got that piece off!!!!! Finally!! But..... Now I got the same problem with the lower piece and 3 bolts this time.. This is unbelievable its driving me nuts.. I drilled out these bolts now also but this piece really doesn't wanna come off... How can I get it I pry apart because I got no where to get an edge on it...? Very annoying!

 

[quicktach]

Re: Removing rusted bolts HELP!!!

KROIL is excellent for seized nuts/bolts/studs etc. Apply liberally and let it soak for a day. Then repeat.

 

[mercurymang]

Re: Removing rusted bolts HELP!!!

Kroil. Thats the stuff. Heard it's really good. Actually, I saw a list somewhere where they actually did a scientific study with everything from nothing to wd40 to home brews, etc. They took created rusted bolt scenarios that were identical and used the penatrents in equal amounts and then measured the torque required to remove them. Kroil was near the top of the list. Actually what was at the top of the list was a home brew of acetone and transmission fluid as I recall.

Edit: I did a search and found it: Best Penetrating Oil Test, surprise winner - Ford Truck Enthusiasts Forums

 

[100333624]

Re: Removing rusted bolts HELP!!!

Kroil. Thats the stuff. Heard it's really good. Actually, I saw a list somewhere where they actually did a scientific study with everything from nothing to wd40 to home brews, etc. They took created rusted bolt scenarios that were identical and used the penatrents in equal amounts and then measured the torque required to remove them. Kroil was near the top of the list. Actually what was at the top of the list was a home brew of acetone and transmission fluid as I recall.

Edit: I did a search and found it: Best Penetrating Oil Test, surprise winner - Ford Truck Enthusiasts Forums

Awesome thanks for the post! Maybe I will make my own home brew in the future when needed! Fortunately I got them all out! Now I just have to deal with getting the broken bolts out! I absolutely ruined the holes on the lower exhaust extension plate thanks to one stupid bolt that just didn't wanna come out. Now I gotta find me another part, oh well I guess you live and learn right...

 

[jimbo_jwc]

Re: Removing rusted bolts HELP!!!

Wow mention a product on here and Bang a link comes to top of page with special Google offer . Doesn't get any easier , Two new king size cans delivered to my barn . ps this usually wards off stuck things for awhile . Its that Good haha .

 

[gm280]

Re: Removing rusted bolts HELP!!!

I hope you got everything apart now and can retap those threads to clean up the holes before reassembly. As I stated previously, go back with stainless steel and you will avoid this situation in the future if that ever needs disassembled again (probably not though). If the holes are torn up beyond a simple retap effort to correct, you can purchase Heli-Coils and install them where needed. They will hold at least the same amount of torque or more. I’ve used them many many times in my past for just such situations with great results. Hope you get everything working soon...