Oil cap

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Classiccars
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Oil cap

Post by Classiccars »

Hi I have a plastic screw on oil cap but eould maybe prefer a metal one.Bought one before that turned out to be the wrong size.Can someone advise a cap for an ital A plus cover please.
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Re: Oil cap

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svenedin
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Re: Oil cap

Post by svenedin »

Before you replace your plastic oil filler cap with a metal one, be aware there are 2 types of plastic cap: long-vented and short non-vented. Which one is appropriate depends on the engine breathing system your car has.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Bill_qaz
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Re: Oil cap

Post by Bill_qaz »

philthehill wrote: Mon Sep 01, 2025 9:30 pm You could try this cap:-
https://www.ebay.co.uk/itm/334627673071 ... R-Kmuu-gZg
Just purchased one of these Tudor caps, seems reasonable quality. I needed non vented for my application so simply put shiny self tapping screw in the breather hole in cap.
Regards Bill
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Re: Oil cap

Post by Classiccars »

Thanks all just yo update this is yhe rocker cover which is morris unlike the 1275 engine so it would be yo fit this cover please just yo be sure.
20250902_112051.jpg
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philthehill
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Re: Oil cap

Post by philthehill »

The Tudor' oil filler cap will fit the rocker cover shown in the photo above. If a non vented cap is required use a screw as Bill has done.

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svenedin
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Re: Oil cap

Post by svenedin »

I would just mention for any future readers of this thread that the metal vented oil cap is likely to have little restriction whereas the plastic vented cap is deliberately restricted and has a gauze filter so that dirt is not drawn in. It is not actually a "vent" in the long-vented plastic cap but an inlet. This restricted inlet is necessary with closed-circuit breather engines (designated 10ME) that use a PCV valve. If the wrong type of cap is installed it can lead to unexpected rough running or problems with the crankcase breathing system. A little bit of engine bling may cause issues in other words.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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Re: Oil cap

Post by Classiccars »

Food for thought thanks very much.
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Bill_qaz
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Re: Oil cap

Post by Bill_qaz »

What does the breather from your rocker cover connect to?
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Re: Oil cap

Post by Classiccars »

That's a left Iver from when the engine was blowing out oil under pressure so put on at a higher level than the rocker so the oil went back to the engine instead.
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Re: Oil cap

Post by Bill_qaz »

Just fitted alloy valve cover and the Tudor cap. Drilled and tapped cover for banjo to connect original pipe to air filter case. Sealed breather hole in cap with screw.
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Regards Bill
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