Finishing up a "Jemma" radial, and wondering if anyone has experience using grease to lube the cam/gearcase of a radial. What product does Black & Decker/Milwaukee/Makita use for lube in their tools? Would this be suitable? It would seem that gear oil is going to leak past the tappets unless drained after running. I used sealed ball bearings throughout this build. Any info appreciated.
Radial cam/gearcase lube
- Thread starter l.dullum
- Start date
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The Jemma is a seven-cylinder spark-ignition radial of 40.5 cc designed by Eric Tomlinson and published in Strictly I.C. in the Dec. 1999 issue and following. It features open pushrods and rockers. The gear train is a 8 to 1 reduction using spur gears only (no internal gear) and the tappets are plain dome-headed hardened drill rod running against case-hardened cams. The cam/gearcase is sealed off from the crankcase. The crankcase is lubricated by blowby from the fuel/oil mix. Hope this add'l info helps clarify.
Larry
Larry
Tomlinson
Well-Known Member
Hello l.dullum.
When I built this engine, I expected to get some oily mist blowby from the crankcase into the cam gearcase (My main bearing was not sealed) . In addition, before running the engine I would depress one of the valves in No 1 cylinder, remove the pushrod and tappet and give a couple of squirts of gear oil through the tappet hole; a few seconds job.
Oil seepage past the lower tappets was minimal.
To answer your original question, If I were to use grease, in the absence of oily mist from the crankcase, I would be tempted to still introduce an occasional squirt of oil from the top.
Eric T.
Some cams just use oil drip
It can be as little as 10W oil .
The blow back of fuel and oil will wash away the grease.
On some automatic machines they just use way lub.
Dave
It can be as little as 10W oil .
The blow back of fuel and oil will wash away the grease.
On some automatic machines they just use way lub.
Dave
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