I’m restoring a 1960 Dominator 99 engine. My timing cover is the type that has the oil pressure relief valve fitted to the inside of the cover. I know that Norton in a later year made a timing cover where the oil pressure relief valve fits onto the outside of the cover. Would I be able to use one of those - are the covers interchangeable? The reason I’m considering doing it is because I’m unable to undo the oil pressure relief valve in my current cover so I can’t check the internals. As the engine has done over 90000 miles, I’m checking every single part to make sure it’s still usable. I’m nervous about using heat on the oil pressure relief valve in my current cover in case it damages the metallurgical structure of the aluminium. Any advice gratefully accepted.
Thanks
Regards
Tony
Mix & Match
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You'll need to hold it in a…
You'll need to hold it in a vice with good soft jaws and use a big, correctly-sized spanner. Gentle heat is OK . There is only a spring and a piston in the inside prv. The filter is in the bit accessible from the outside. New parts are available from RGM and ANL. Good luch, Howard
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Thank you both. Philip,…
Thank you both.
Philip, that service notes extract is so useful. Did it come from a book that is still available as I’m wondering what other very helpful info it contains? It’s good to know I’ve got a few options if I can’t shift the oil pressure release valve cap in my original cover.
Howard, thanks for the advice regarding the removal of the release valve plug. I’ll get a blowtorch on it so as not to put too much heat into the cover.
Thanks again to both of you.
Regards
Tony
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Gently Does It
Tony, just to add my two pence. Following on from Howards advice re-soft vice jaws, the correct spanner size and gentle heat, etc. I've been down this road before and ended up with a cracked alloy casting when trying to remove a stubborn fastener, (not from a bike I must add). It's really best done as a two man job. One to gently heat the area immediately around the offending fastener. The other to gently apply lots of even force. Don't be tempted to try to shock it loose (aka, belt the daylights out of it), otherwise the heated alloy may crack. Also when you have removed the valve, gently reheat the casting for a few minutes and cover it up to let the casting cool slowly to release any stress that you may have created in the local area of the valve. Cover it with some old woolen material, (old blanket, jumper or similar, welders gauntlets etc) don't use modern materials it'll melt on. Whilst it's cooling go and stress relieve with a brew..
Regards
John
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Good Advice
John is quite correct about being careful with applying heat to the cover. It is all too easy to end up with a crack or warp due to overdoing things.
Howard....we seem to have an appreciative customer, so we must be doing something right. I will send you this Chapter once the five sections within it are completed. It's a biggie!!!
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Tony......you can use almost any of the 12 versions of cover made for the Dominator engines. There is just one exception.....the 11 hole version made for the first Model 7 bikes back in 1948/49. This cover might need a little creative engineering to fit leak free.
The attachment has been borrowed from the Dominator Service Notes and should be of some help,