Rusty exhaust bolt question

[Sebastian S]

Looking for a bit of input on this...
I'm removing the rusty old exhaust from my Wasserboxer MV engine, and have run into a bit of trouble with the bolts on the front of the engine:


It's pretty much the same on both sides. Both of these should be bolts right? Or is the lower one usually a stud? A bit hard to tell, but looks like it (especially on the image actually). They have rusted to a kind of conical shape which makes the tools slide of... I have the Irwin Bolt-grips but they won't do the trick on these ones. A bit hard to flatten down the sides enough to get a smaller socket on aswell, not much room to work with. I unfortunately don't have a welder so have to find another way. I'll probably try a bolt extractor (easy out) next, or would you recommend something else first?
I really don't want to pull the engine because of broken bolts...

[lloydy]

The bolts on the turbo of my old engine looked like that, the guy who eventually got the turbo out reckoned they had been welded or that metal filler stuff put on it. he used some sort of easy out tool to remove one of them, the other stayed put and had to be removed by the turbo recon people

[Hacksawbob]

You can try a hammer and old chisel or a proper metal cold chisel (with eye protection) to get them moving. Good in a tight spot, but this is one of the reasons that people end up removing the engine.. especially if they shear off Easy outs are usually more of a problem than a solution, they snap off and make life even harder.

If I have a nasty one this is the route I take,

wire brush +chisel to clean faces
plus gas
six sided socket
heat til cherry red
chisel
weld a second nut on
centre punch and drill out starting small and incresingtil only threads left
if needed re-drill oversize and fit a timecert

much easier with the engine out!

I have heard others use freezing tools aswell, rust off?

[Mickyfin]

Mine look like that, and am dreading removing them when my new system arrives.

[kevtherev]

Heat...lots of heat and a lot of patience

[Mickyfin]

Cheers, guess I need to buy one of those portable gas thingy's to apply the heat.

[Sebastian S]

Thanks guys! Will get back on them tomorrow... Will go nice and easy. I reckon welding on a nut would be the best route, maybe time to buy a welder... Quite a tight spot though, especially on the left side.

And yeah, heat really helps. The bolts on the rear of the engine came out easily after lots of heat. Just be careful with those fuel lines and plastic parts and stuff.

[AngeloEvs]

Mine were like that and each exhaust was cut away close to the flange exactly as in your photo. The mechanic cut carefully through the remnant of the exhaust leaving the flange under each nut. He drifted each section anti clockwise and looked for signs of the bolt head moving, welding the bolt head to the flange if necessary thus applying heat as well, some were removed just using mole grips on the remnant of the flange under the badly erroded bolt head. One didn't budge even with welding/heating up and, in his opinion, was a candidate for shearing which would have meant dropping the entire engine for one sheared bolt.

He ground the head off and was going to weld a new nut on but we found that the standard exhaust flange was thicker than the flange on the SS exhaust that was to be fitted, quite a bit of the thread actually protruded proud of the new SS flange. The thread was in good condition - the head had deteriorated and not much left of it. We discussed the options and decided not to remove it but try and use it as a stud, we took about 2mm off the SS Flange so that a washer could also be fitted. It's been fine since but cutting through the flanges was done with a compressor driven hacksaw blade and you have to be careful to stop when you reach the gasket so as not to damage the face.

[Sebastian S]

Finally had a bit more time today, and.. success!
All studs and bolts out! It took lots of time and effort but well worth it not having to remove the engine.

Started out with the chisel, removing all rust and loose metal. On two bolts I then could hammer on a 9 or 10mm socket. Then lots and lots of heat. Maybe one or two turns on the ratchet, then more heat etc. I did snap one bolt, it was to far gone, but got lucky and could use a pipe wrench or whatever they are called in english and got the rest out quite easily. The studs were removed the same way.



Victory!

Now on to the rest...

Thanks for all the response, very good too have a second opinion on these kind of things.. !

[Sebastian S]

AngeloEvs: thanks for the tip on using the snapped bolt as a stud! I did consider copying that approach on the bolt that I snapped but it wasn't long enough and didn't want to remove that much on the flange on the new exhaust. Sounds like a good trick though!

[kevtherev]

Heat...lots of heat and a lot of patience

that's ok no problem

[Mickyfin]

Great news, glad you sorted it. Can I ask, what did you use to apply the heat? I ask as I need to do exactly the same soon.

[Sebastian S]

http://biltema.se/sv/Verktyg/Svetsning- ... are-17608/" onclick="window.open(this.href);return false;

Heat...lots of heat and a lot of patience

that's ok no problem

Huh?

[Mickyfin]

Cool, thanks

[ghost123uk]

Heat...lots of heat and a lot of patience

that's ok no problem