"Tin Lids"

[Rick F]

On another thread, Ruairidh mentioned that he never fitted oil baffles ("tin lids") when rebuilding an engine. I always do, since they were fitted throughout the life of the Seven and, even allowing for the eccentricity of some of the features, I feel sure that they would have been omitted had they not been considered  necessary - or at least desirable.

What do the rest of you think?

[Alan]

I’ve not fitted them for years, never noticed the difference.

[Andy Bennett]

Another bit relevant to my rebuild as I don't know if I have oil baffles at the moment but have obtained a set of used ones anyway as the opportunity was there.

Alan
Could this be because you are better at building engines than most and so the benefit from the baffles presumably keeping some oil away from the bores is needed on a regular engine but not one built by you, or because new pistons/rings are better than originals and so the engines simply don't need them any more, but did originally?

Andy

[Nick Salmon]

I always leave them out and have never noticed or seen any difference over time.

[Alan]

Andy, might well be modern pistons, rings and bore machining are better. As for the other, I’d doubt that.

[John Mason]

My engine has run without them for the last 12 years without any notable difference. It is also much less fiddley when reassembling ( if you use the method of putting all 4 pistons and rods into the bores then putting the block to the crankcase).

John Mason

[Chris KC]

My engine has a Reliant crank & rods thus has a 1/8" spacer plate twixt block and case, as Reliant rods are longer. The plate has slots which allow the rods to pass through, thus functioning to some extent as a substitute baffle.

[Charles Levien]

Probably best leaving baffles out with a pressure fed engine — there’s a lot less oil mist than spit and hope and the little ends miss out.

Charles. Also in deepest Norfolk

[Ian Williams]

I am also in the never use the baffles camp, I have built dozens of engines both road and race, never had a problem.

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PS Chris, I am confused I thought Reliant rods were shorter, the ones I have used are, you do have to shorten the Reliant pistons with a scraper cut, perhaps that is what you meant?

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PPS Sorry Chris I have just realised I am being stupid and confusing Renault with Reliant, old age is creeping up on me Doh!

[Colin Morgan]

In Barney Sharrat's book on 'The Austin' p28, he quotes George Coates talking about road testing Sevens: "In the early days of the Seven we were plagued with 'smokers'.  We were trying to turn out one hundred per week but there were so many smokers that numbers were well down for a long while.  A smoker would show its colours on the dirst descent of Rose Hill and continue smoking all the way back to the Works.  The trouble was eventually cured with oil control rings and by placing baffles in the base of the cylinders."

I wonder if this fix was belt and braces and the baffles have never contributed much to the solution?
Colin