Joined: Aug 2017 Posts: 1,644 Threads: 93
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Location: Monmouthshire
Austin managed to make the Seven affordable by keeping production costs down. Using a valve chest/tappet cover made from flattened out biscuit tins undoubtedly saved three farthings, but costs rather more per month in oil loss. I have tried silicon o ring material, pretend to be as delicate as a piano tuner in tightening but not overtightening the knurled knobs. Using blue goo worries me in case I have not been sufficiently sparing, and some might get into the oil and thence jets etc. I have wondered whether to rake through the stores in search of some boatbuilding tools of my youth, but I'm not sure that using a caulking mallet to drive oakum round the cover would work. Yesterday I spent happy hours on the phone talking to our invariably helpful and friendly cherished suppliers. Sadly, they either did not choose to stock aluminium covers, or had none in stock.
Does any one either have an ali cover surplus to their requirements, or suggest a supplier, cherished or otherwise, who might have one that I can purchase?
Joined: Aug 2017 Posts: 1,200 Threads: 71
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Did you talk to John Barlow? He certainly used to do them...
Joined: Aug 2017 Posts: 783 Threads: 26
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Location: On a hill in Wiltshire
Are you sure it is the fault of the tappet cover?
On two cars I have been involved with recently the oil appears to be coming from the fuel pumps, having at first been blamed on the tappet covers.
Joined: Mar 2015 Posts: 5,464 Threads: 231
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Location: Scotchland
Has the leak become worse quite recently or has it always been there?
Joined: Aug 2017 Posts: 1,644 Threads: 93
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Location: Monmouthshire
Thanks for responses. John Barlow only has blanks in stock and is not sure when he will be able to get them machined. Petrol pump leaks are not unusual. Before I put this rebuilt engine back in, I took care on the bench to make sure both faces were clean and compatible, so far this has remained tight.
Ruairidh, I've got used to cork seals slowly giving up and needing replaced almost annualy. The o rings, advised on the forum, don't seem to last any longer. This leak slowly increased over the last month or so. Putting new o ring on last week has limited the leakage visibly to the rear bottom, but it is still far from tight. That is why I was thinking that that the rigid ali cover might be the solution. Certainly there were no original pressed tin tappet covers visible under bonnets at Shelsley on Sunday!
Joined: Aug 2017 Posts: 691 Threads: 37
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Location: The Scottish Border
With some luck you might find a Reliant Alloy Cover on Ebay.
I ground off “Reliant” and polished and lacquered it , finishing
it off with two nice Alloy thumbscrews from the A7 Workshop.
This cover takes an O ring rubber.
Regards
Bill G
Based near the Scottish Border,
Joined: Aug 2017 Posts: 1,644 Threads: 93
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Location: Monmouthshire
Oxfordshire Sevens also out of stock. However I will now remain sitting out in the sun with the ipad and try and track down aReliant cover, never heard that suggestion before.
Joined: Mar 2015 Posts: 5,464 Threads: 231
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Location: Scotchland
If you fitted a new silicone gasket (completely dry) and a leak still occurred then I would suggest the block to crankcase gasket is the cause. I have zero leaks after 5k with silicone gasket and original tapper cover.
Do check that the cover is sitting clear of the manifold and crankcase - if held up on these it will never seal.
Leak at the bottom rear indicates that your rearmost block stud may be loose. Tighten it, and others, with extreme caution!
