Right stuff is the wrong stuff

I made a huge mistake the last time I had the chaincase off of my MKIII. I had tore the gasket and instead of
waiting on a new gasket....I used Permatex Right Stuff as a gasket and it work great as far as no leaks but now
I am trying to remove the cover and nothing seems to work. I tried working a single razor blade (with acetone) but the joint with no gasket is thinner than the blade. Working thru the inspection holes...I tried using the clutch center to push on the outer case using a clutch removal bolt with washers/ nuts to push on the cover. Tapping on the cover while pushing with the removal bolt...no help...
Any ideas on how I can get enough room to get a razor blade started...
I am at a standstill until I get this cover off... I think JB Weld would be about as bad as this "Right Stuff"
Thanks for any suggestions,
Rod

Heat? Heat gun first then maybe a MAP torch.

It is rated @ 500 degrees.... I did try a heat gun and did not notice any help... I tried tapping the razor lightly
with a hammer... Only goes in 1/32...
Rod

When I tried to get the cover off my MK3 I had to use heat and a 2" wood chisel (flat side facing out). Originally tried pullers in the access holes. Sounds butcherous but It didn't leave any marks. (I was very careful indeed) Somone had used a similar product, didn't leak but.........

Heat cycles and solvent do help sometimes over eons so I use crimp back one sided razors to align with semi-invisible seam then hammer it in and others in. If breaks off as house razors tend to do must escalate to utility knife blades till can get chisels in w/o marring. Add glued on covers cases and heads to list of hardest things get past w/o injury. The mental forum focus you've got on that stupid seams chemical bonds will gradually let go under the pressure. See if it don't work magic for you too. Guess why I'm so sold on extra expensive Hylomar.

I have always used hypomar in the past with a gasket and have had no problems. How could I be so stupid and try
something new when the old had no problems... I am afraid of destroying the cover just to get it off...
Damn,
Rod

Remove the starter. The bottom bolt also is the case bolt. Your might be able to get a long brass punch in from the timing side and give it a couple of sharp hits. I don't know if you will have a good enough angle but it might be worth a try.

I removed the starter and there is room to get to the back of the outside cover. The only thing I could find is nut driver.... A few sharp taps with a hammer and nothing. Maybe a wood dowel chuck up in a hammer drill + pressure
at the clutch center bolt/washer set up?
Rod

The Right Stuff silicone sealant is swellable and will soften with time to a point that you will be able to get it apart. In the mean time don't panic, be patient. Bashing it with drifts and hammers is not going to get it apart. You need a combination of swelling and mechanical force to get it to move. A non-polar solvent like heptane or mineral spirits will swell the silicone, thereby significantly reducing its strength and allowing you to force your way into the joint. The Right Stuff has relatively high x-link density and is therefore not as swellable as lower x-link density analogs (Permatex Ultra Blue), but it will succumb to solvent over time.

Toluene is also an excellent solvent and possibly a bit more aggressive on the silicone, but it is also aggressive on other things like paint, wire insulation, etc, therefore, I'd stick with heptane or spirits. If you don't mind the stink, non-oxygenated gasoline is also a very good solvent for swelling silicone rubber and quite gentle on everything else.

If confronted with your situation, I'd start by draining all oil out of the primary and refilling with the swelling solvent of your choice. This allows liquid and vapor solvent to begin swelling the silicone from the inside. I'd also rig up something for the outside of the primary that allows solvent to be on the cover seam for an extended period of time, e.g., perhaps a strip of toweling that is saturated with solvent, and then wrapped as best you can with a layer of Saran or other thin pliable plastic film (garbage bag?) secured with tape to seal the system and minimize evaporation.

Now comes the hard part. Go away and leave it alone for days and let the solvent do the work for you. Check to assure the joint has solvent around it, and if it is getting dry, renew the solvent. After several days you should be able to make headway with razor blades as others have described, or with leverage as you metioned.

If you have the interest, you could conduct a separate experiment to asses the swellability of a thin section of "The Right Stuff". Coat out and cure well a thin section of "The Right Stuff". Place the cured silicone rubber into the solvent(s) of choice in a jar and observe/probe/pull it periodically over days to see how much it weakens.

Good luck and let us know how you fair.

Maybe you should contact Permatex and see if there is a solvent that will break it down. Something like acetone or naphtha. I would hate to see you damage that case. Good luck w/ that.

If even WZ's wise calming advice fails there's a non fight hippie way to consider, fill with dry beans, sealing up what Ya can leaving a place to syringe needle in hot water to keep wet as can then place pad under the cover to pick off of next day.

Here's the data sheet if that helps. Says to avoid contact with gasoline.

http://www.permatex.com/documents/TDS/a ... /34310.pdf

Last call...tap some of the pin holes 5/16 [ cover only] and jack the cover off, screw in the back cover a grub screw for the 5/16 jacks to push on then repair the holes if you feel the need. Prob three well placed will break the joint?

A few psi of compressed air inside the primary. Definitely dangerous but could be interesting. I would not get in front of the cover.

the air will escape via the rear clutch hole? If it didnot as you say "stand back"

Dances with Shrapnel said:

A few psi of compressed air inside the primary. Definitely dangerous but could be interesting. I would not get in front of the cover.

Click to expand...

+1 for Dances! +2 for John Robert. It has to work if you tap enough holes. The gasoline idea in the case sounds promising as well.
Dan.

Not sure about putting solvent inside the cover. Stator may decompose.

I know this is not directly helpful but…do you HAVE to take the cover off for some reason right now?

IF I had received a bike in that condition, I would have tried exactly what you have so I'm not sure I could offer anything that hasn't been suggested. But it's hard for me to imagine that a razor blade can't get "into" the seam somewhere around the case. I assume you've tried various locations for that.

Does a MkIII (you mentioned a starter) have the same clutch center outer case fitting as the earlier models - the large center plug for clutch adjusting? If so, removing that plug MIGHT allow you to fit some sort of tool into the case so that it fits in close to the mating surface between the inner/outer chain cases and use it as a lever.

I would think that a heat gun would ultimately prevail - it should be able to get hot enough to do the job if it's a heat gun, not a hair dryer. As noted, a torch certainly would. I'd prefer NOT using the torch though I've used one on tranny cases to pull the layshaft bearing. Heat + the razor blade HAS to work! (unless, of course, it doesn't)

FWIW, I like Permatex MotoSeal on most gaskets - it's basically the same thing as Yamabond. I like Hylomar but Motoseal is much cheaper and works just as well. Silicone sealant is a tool of the devil and, IMO, belongs only in bathtubs and showers.

motorson said:

+1 for Dances! +2 for John Robert. It has to work if you tap enough holes. The gasoline idea in the case sounds promising as well.
Dan.

Click to expand...

If you drill and tap the clutch center cap for 3/8 coarse or 7/16 coarse and thread a screw down to the clutch adjuster.
actuate the clutch... push off cover...in addition to JR jacking screws
Also long jacking screw in threaded fill hole ???

htown16 said:

Not sure about putting solvent inside the cover. Stator may decompose.

Click to expand...

The stator should have good solvent resistance, especially if it is a late style variety that is fully encapsulated. Even if early style should easily tolerate mineral spirits.

mike996 said:

I would think that a heat gun would ultimately prevail - it should be able to get hot enough to do the job if it's a heat gun, not a hair dryer. As noted, a torch certainly would. I'd prefer NOT using the torch though I've used one on tranny cases to pull the layshaft bearing. Heat + the razor blade HAS to work! (unless, of course, it doesn't)

Click to expand...

We are accustomed to the thermal behavior of epoxy and anaerobic threadlockers that exhibit structural strength at RT but soften dramatically with heat, e.g., JB weld (and any other RT cure epoxy), at RT (glassy state) exhibits structural strength, but at 212F (100C) (rubbery state) is nothing more than a firm rubber. So we know that heat dramatically alters the adhesive strength of such systems thereby allowing us to remove or loosen assemblies when heated.

However, silicone rubbers are different, in that they exhibit essentially constant modulus from ~ -40F (-40C) to ~ 450F (230C) where they begin to thermally decompose. Although silicone sealants (rubbers) are much weaker adhesives than epoxy and high strength threadlockers, because they are much lower modulus materials, their modulus and adhesive strength changes minimally, if at all, over a very broad range of temperature. So heating silicone sealants will not alter their strength like it will an epoxy or threadlocker. That said, heating an assembly still induces stress/strain, due to dimensional changes of the assembly, and this added stress/strain can certainly assist in breaking the adhesive bond. For that reason I too find modest heat useful to disassemble things adhered with Permatex Ultra Blue silicone. Just don't expect them to fall apart with heat.