Oil Gallery Cap Seized

[Hamza]

Hi guys,

Started working again on my engine after 8 months...been able to spend 2 or 3 hours daily and hope to squeeze in a bit more considering holiday season is approaching!!

So I was opening all the oil path/gallery caps to put in new O-rings. All of them opened fine, except for the one on the Right side of the lower crankcase. I managed to damage the hex head on it...damn thing is on tight...I tried heating it up with a heat gun for about 15 minutes and then tried cracking it....no luck...i opened the cap on the front to get a view and it seems that the threads are galled...I have taken a photo also but they came out rotated 90 degrees counter clockwise on the attachments...



I wanted an opinion/advise...I was wondering if it may be wise to leave it like that...even though I have spent good $ on spares for a ground up restoration and it seems wrong to leave it in there considering I have stripped down each nut and bolt so to speak......at the same time I am wary that if it is seized most likely the threads will not be good enough to screw in a new one....I will most likely need to drill out the threads and chuck in a bush then re-tap it so an original cap will fit in.........

I would really like to test it to see if it leaks...if I cannot then I am contemplating making my peace with it and moving on...the thought of putting sealant on the outside if it does leak did cross my mind.........

[Hamza]

Photos..

Oil Path 1.jpg

Cap.jpg

[Jeff Bennetts]

Put some real heat on it, propane or map gas!

[Hamza]

Thanks Jeff....I have a propane torch..how long of an exposure is safe do you think?

[Hamza]

Its a butane torch.....should work?

[Jeff Bennetts]

It would be nice if you had the correct socket and impact wrench, some decent heat around the boss/case and a couple taps and it should spin.

Make at least 4 or 5 slow passes around the boss with the heat, try to loosen it, repeat if needed.

[Hamza]

So i used a 14 mm socket on it..a 13 mm was too small...tried a small impact but thats what really ruined the hex head on the cap.....I will be giving it another shot tomorrow morning as the workshop is at my office...I will give it a healthy dose of heat...is there any danger of damaging the aluminum crank case though if I give it too much heat?

[CBX-tras]

See my answer over at CBX World.

[Rick Pope]

Since the cap is ruined, why not trim away the flange? That would likely get rid of the material that's giving the most resistance to rotation. It might also let the hex portion fall off. If so, go in with a small tool to split the threaded portion internally. With a little care, and luck, the threads will be fine.

[Larry Zimmer]

A few thoughts all with some heat:
Try to find a 6-point hex socket.
Grind the face of the socket so that the hex is flush with the end face of the socket. All sockets have a 'lead-in' chamfer. The hex on the plug isn't deep enough to adequately engage the hex of the socket with the lead-in chamfer on the socket.. That's why it slips and 'chews' the cap hex without turning it.
If all else fails, try a pipe wrench.

[Hamza]

Since the cap is ruined, why not trim away the flange? That would likely get rid of the material that's giving the most resistance to rotation. It might also let the hex portion fall off. If so, go in with a small tool to split the threaded portion internally. With a little care, and luck, the threads will be fine.

Thanks Rick...If all else fails I might have to go down this route...

[Hamza]

A few thoughts all with some heat:
Try to find a 6-point hex socket.
Grind the face of the socket so that the hex is flush with the end face of the socket. All sockets have a 'lead-in' chamfer. The hex on the plug isn't deep enough to adequately engage the hex of the socket with the lead-in chamfer on the socket.. That's why it slips and 'chews' the cap hex without turning it.
If all else fails, try a pipe wrench.

Thanks Larry..so if I understand correctly, get rid of the lead in chamfer on the socket so it grabs the hex better...Ill give this a go or maybe just torch this bad boy up and pipe wrench it...

[Hamza]

I will revert back with how I go tomorrow...Thanks guys...you guys have given me confidence to get this open now and not just leave it in....

[Larry Zimmer]

A few thoughts all with some heat:
Try to find a 6-point hex socket.
Grind the face of the socket so that the hex is flush with the end face of the socket. All sockets have a 'lead-in' chamfer. The hex on the plug isn't deep enough to adequately engage the hex of the socket with the lead-in chamfer on the socket.. That's why it slips and 'chews' the cap hex without turning it.
If all else fails, try a pipe wrench.

Thanks Larry..so if I understand correctly, get rid of the lead in chamfer on the socket so it grabs the hex better...Ill give this a go or maybe just torch this bad boy up and pipe wrench it...

Exactly.

[Hamza]

Hi guys,

Happy to report back that a butane torch, some smacks on the side and it opened right up..had to use a set of adjustable lock pliers on the ruined hex...

Alls well that ends well...

Thank you for all the advise!!

P_20211101_133621.jpg

P_20211101_133623.jpg