Corrosion on engine exhaust mounts
 

Hey guys,

I have 2 problems with my 2002 sv650. The first one is as you can see there is a fair bit of corrosion which has eaten away at the engine mount and I think needs to be repaired. A fair bit of the metal is gone and I'm worried about structural integrity or it snapping open when I tighten the studs in there.
The second issue, that exhaust is just STUCK! I read that it can "weld" itself over years of use and rust/corrosion. Any tips on how to remove that?

Slowly doing a full overhaul of the bike so I'm patining parts and replacing/repairing rusty bolts, studs, etc

Re: Corrosion on engine exhaust mounts
 

If you don't actually need to disturb or remove the exhaust bolts, I would just leave them alone as they could well snap when you try and remove them. If that did happen, you'd go from having a running & riding (but slightly scruffy) bike to a bike that you can't ride. The worst case with old, corroded and broken bolts is that they snap flush with the head surface, and you'd have to remove the cylinder head and have the remnants of the stud spark-eroded away. It's risking a hell of a lot of hassle for the sake of appearance.

If you do want to try, start by applying a corrosion-killing penetrant like ACF-50 and letting it soak before you even try to move the bolts - I think you'd need to apply it regularly over a period of several weeks.

The exhaust pipe itself will clean up if you paint it with some Harpic Power Plus 10X toilet cleaner, work the stuff in with an old paint brush then leave for 5 minutes and rinse off.

Re: Corrosion on engine exhaust mounts
 

Thanks for the helpful reply Craig! I see what you mean there and you're right, it's not worth the hassle. I will leave the studs alone and simply put on new nuts as I removed the old ones, which were in dire state

How about the blue/white corrosion there on the engine part itself, should I do anything about that? I'm worried if I don't clean that up and have it welded then shaped (this is the solution I found at least) it will keep corroding away until that engine stud mount will be completely gone. I can already scape it away quite easily because it feels like some of the metal has turned into powder/mush.

Re: Corrosion on engine exhaust mounts
 

Those studs look like my studs - dare not try to remove nuts for the reasons Craig states. How about having a couple of domed nuts made. You could reduce the stud length perhaps. (Only if you are super pedantic - not meant in an insulting way)

Re: Corrosion on engine exhaust mounts
 

Keep it covered in generous amounts of ACF50 and don't look at it.


After the fun I had removing snapped header bolts I wouldn't do it again unless I was sure they would come out cleanly and easily.

Re: Corrosion on engine exhaust mounts
 

Thanks for all the advice guys. Definitely stopped me from doing something potentially stupid! Not touching those mounting bolts. The last thing I need is to spend money on removing a snapped bolt or two, or god forbid having to open up the engine, etc.

But any advice on 'this' bit, should I just use lots of that ACF50 over a period of time and leave it as is, or should I again, try to clean up the corrosion with ACF50 and have someone weld back/build back the metal that has been corroded, then re-shape it with a grinder, etc?

Thanks!

Re: Corrosion on engine exhaust mounts
 

You could put it together then spray the studs with heat resistant silver spray paint. (cannot remember what it is called but Halfords stock it) I use it every 5 or so years to paint the barrel on the Cub.

Re: Corrosion on engine exhaust mounts
 

I'll be sure to look into that, thanks for the tip Red

Re: Corrosion on engine exhaust mounts
 

I swapped all the exhaust studs on the bikes I am doing up. Most snapped. Managed to weld alot of them out, the others were drilled and retapped. Added some of the other stuff in the pics that I am making for the bikes.

After starting on the first bike it was clear the engines had to come out so it was easier to do alot of jobs, including the studs.

Re: Corrosion on engine exhaust mounts
 

Damn, that seems like a lot of work just for the studs, really tells me not to mess with the studs for the time being. Going to move houses soon as well and the last thing I need is to have to pay to move the motorcycle instead of just riding it. Great work with those though and thanks for the pics.

Your picture is clearer than mine so I used it to show what I'm having a problem with; all the corrosion is there, the bit of the engine that the stud screws into