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Good AM from Green Bay OG Members/Experts

I am restoring an MS 70 and need some advice on rewiring the light manifold. Regardless of the pump model, removing the circular aluminum threaded "explosion proof" lid to these junction boxes has always proven to be difficult and often times resulted in damaging the lid, hindering its reuse. OTHER than heat, has anyone discovered the "best practice" for this step in the restoration? If you would rather chat than type, my cell # is in my profile.

Thanks Neil

I use a cold chisel and make four evenly spaced groves on the cap, then take a flat punch and work the groves around the cap until the cap loosens. I then file the rough edges and fill the groves with body putty. Richard

I have found that using an 8 point socket with a breaker bar helps a lot.

The last one that I did, I heated the plug with a propane torch. I used a 3/4 socket backwards, putting the square end of a 3/4 drive socket on the cover and turning the socket with a pipe wrench. The pipe wrench left marks in the socket but the plug came out without damage.

Neil, Even though you stated "other than heat"....let me jump in...After reading all of these replies, I am guessing that all of these attempts were with the light manifold removed from the pump frame? When I was restoring a bunch of MS 80's, same manifold design, I'd have 5 or 6 on the bench and do them all at the same time. It is nearly impossible to remove the access nut while in the frame as there is too much flex, of the frame, to allow the cap to break free. Remove from the location. Clamp in a strong vise. Usually a pipe wrench worked with some Kroils to penetrate. On difficult units, since I always replaced all the wiring and porcelain sockets, I would use heat. Sorry but there are times that heat is the only option. First try a propane torch moving it all around the area and spraying with Kroils after you remove the flame. You might need to go to acetylene but be careful not to over heat. One last resort, use a thin cut off wheel to cut into the area between the cap and where it meets the cup. Work around under the cap slowly and not too deep. Use Kroils from time to time. This is the dirtiest way to get it done but usually works. have no more tips on this as I have used all of the above to success in many restorations. Regards, PaulI

I have had good success over the years with a little heat from a propane torch around the threads on the body of the manifold. That is the part that you want warm and to expand. Then spray some penetrating oil into the threads and it will usually come off with ease.

My trick to success has been to rest the manifold on the edge of a solid surface exactly where the cap screws in and whomp the living sh&t out of it exactly opposite where it's resting on a solid surface. The impact tends to break the seal so to speak. And yes there is a risk to cracking the housing but you really have to hit it really hard. And besides I don't worry about that because I always have more...lol.

Neil, I’ve done it a few times. I always used Kroil and let it soak for a while. I then use acetylene torch to heat the outer housing very hot, then I go to a flat adjustable pipe wrench and put a 4’ fence post on the pipe wrench and it usually breaks free. Repeat if necessary.

Also, a lot of mechanics know this trick too…. Try to tighten it a little. Sometimes when you try to loosen old bolts they won’t budge because of crud. But if you try the other way, once in a while they budge and it cracks that seal of rust and crud.

Thanks Guys I am now in search of a 4' fence post. I do concur with the "going tight" suggestion. Stay tuned Neil

I put the entire manifold in a bonfire or burn barrel for a while. I break off the porcelain light sockets first with a hammer (use eye protection). When it comes out everything is freed up and the black tar flows out.