Rocker arm oiling

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Putt-Rite

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So our little motors don't have valve covers and oil pumps. How are the rockers arms oiled? A drop before running I assume? How long does an oiling last?
 
I use bronze Oilite bushings in my engine's rocker arms.

RWO
 
I hope I don't sound like an igno, but don't you have to add a drop of oil to oilite bushings every so often? Those big radial engines appear to have exposed rocker arms. So they must be oiled before flight?
 
I have 3 engines with exposed rockers, a Holt, a V-twin and an inline 4 cylinder. Prior to running I put a drop of 30 wt. oil on each rocker which is usually good for a day of exhibition, usually 1-2 hours of total running time. My 302 V-8 had a pressure oil system buy I removed the oiling to the rocker shafts because it would over-oil and smoke. The rocker shaft is hollow so I remove one of the breather caps and feed oil into the shaft. This also is good for the day. I have no abnormal wear on any of the rockers on any of the engines.
gbritnell
 
If you drill a hole with your smallest centre drill through the rocker the CSK recess forms a small resovoir that holds enough oil for a run. If teh rocker is horizontal like a lot of hit and miss engines then drill the end of the pivot and put a cross hole so the oil flows to the rocker like this

DSC05408.jpg
 
I hope I don't sound like an igno, but don't you have to add a drop of oil to oilite bushings every so often? Those big radial engines appear to have exposed rocker arms. So they must be oiled before flight?
The "Oilite" bush manufacturers say no. Oil just washes out the factory lube.

Don't know about big radials. That's true for tires and aircraft engines.:rolleyes:

Bill
 
Early radials did require periodic oiling/greasing of the exposed rocker arms. By the mid 1920's, engine designers in the US had incorporated rocker boxes and pushrod tubes with pressure lubrication of the valve gear, eliminating a maint. headache and increasing reliability.

Regarding Oilite, the common sintered bronze bushings are factory impregnated with 30 wt. oil. As long as they don't get too hot, the oil content will last a long time. For example, fractional HP electric motors in use in most home appliances use Oilite style bearings and they can last many years.

RWO
RWO
 

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