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+--- Thread: Oil baffles (/showthread.php?tid=4125)
Oil baffles - leaf200 - 01-04-2020
Hi,
I am trying to fit a set of oil baffles to a early 1926 engine but I am finding the recesses don’t look deep enough. Where the later oil baffles thicker than early ones?
Thanks
David
RE: Oil baffles - Ian Williams - 01-04-2020
Not in my experience, but I throw them away rather than fit them
RE: Oil baffles - Dave Mann - 02-04-2020
I follow Ian's advice, the science that puts the mixture above the piston also draws the oil through the slot in the baffle.
RE: Oil baffles - Tony Griffiths - 02-04-2020
(02-04-2020, 10:26 AM)Dave Mann Wrote: I follow Ian's advice, the science that puts the mixture above the piston also draws the oil through the slot in the baffle.I bow to Mr. Mann's vast experience and knowledge - all based upon sound empirical evidence. One wonders what, if any, experiments were carried out with baffles by the factory - or, indeed, subsequently by any of us?
RE: Oil baffles - John Mason - 02-04-2020
My engine has run without baffles for the last ten years without problems. I have no scientific proof but I think it maybe something to do with modern pistons having the lower oil ring.
John Mason.
RE: Oil baffles - Bruce Nicholls - 02-04-2020
First thing I threw away in about 1972. Never missed them.
RE: Oil baffles - Tony Press - 02-04-2020
Didn't the factory have great problems with oil burning at start up causing many 'smoking' engines to be replaced at the test stage ?
The baffles may have been an attempt to stop this.
RE: Oil baffles - Bob Culver - 02-04-2020
Somebody must have done a before and after test with no other changes. It is astonishing how much oil a Seven can burn....with baffles. I wonder if supposed to channel downward droplets toward the con rod drillings. Although Ricardo reckons all so hectic that attempts to direct spray futile. Suppose on a racing engine adds slightly to pumping losses. I squeezed them very close on my car but still used 1pint in 300 hot main road running after rebore.
RE: Oil baffles - Ian Williams - 02-04-2020
In my experience with good bores, rings, valves and guide's sevens do not burn very much oil at, all certainly significantly less than a pint every 300! Some engines might leak this amount of oil but properly assembled most leaks can be stemmed to little more than the occasional drip
Edit, I should add that the first engine I built did smoke after new rings, it was the last engine that I used oil baffles on! it was rebuilt again without them and used little oil until i broke the crank.
RE: Oil baffles - Reckless Rat - 02-04-2020
For what it's worth the engine on my RP with oil baffles fitted was burning/leaking at a rate of about 100 miles to the pint before it was rebored. Now with +040 pistons and no oil baffles it hardly uses any at all. Since running in I did a long run across northern Spain with two crossings of the Pyrenees and over 2000 miles it used a pint and a half of oil. Consumption is still improving as the engine continues to bed in.