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smokey Austin 12/4 light ascot saloon 1934
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mid



Joined: 10 Jun 2008
Posts: 136
Location: Northampton

PostPosted: Mon Jun 01, 2009 4:31 pm    Post subject: smokey Austin 12/4 light ascot saloon 1934 Reply with quote

hi all, just wondering if anyone can shed some light on this for me... i have an austin 12/4 light ascot saloon 1934 with a 1535cc side valve engine.

recently (although its only recently i've been following it rather than driving it so it could've been happening for a while) at anything over 40mph or going up hill or under load there is a fair bit of smoke coming from under the engine... when looking under there it appears there is some sort of opeing / breather type thing on the bottom of the bell housing and this is where it appears to be coming from - its definitely more of an oil vapour rather than exhaust, as sometimes if the windows are open it comes into the cabin around the gear stick and it smells oily but not like toxic exhaust fumes.

I am assuming its related as it was much worse last weekend and when we stopped we noticed that we'd lost the oil filler cap - anyone know how this is meant to hold on? was it just a push fit?

i'd like to get to the bottom of this asap as we use the car for weddings - dont really want it filling with smoke with a bride in the back - we've fitted a gearstic gator at the moment which has stopped it coming into the cabin, i just would like to get to the bottom of the problem rather than mask it!

other than this the car is running absolutely fine with no other issues i know of.

any ideas or do they just do this?

Martin
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victor 101



Joined: 03 Apr 2009
Posts: 449
Location: East Yorkshire

PostPosted: Mon Jun 01, 2009 10:11 pm    Post subject: Reply with quote

Sounds like you could have a problem with worn rings/bores, compression escaping past the rings and pressurising the crankscase which would force its way out at the point of least resistence. A compression check would be advisable.
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mid



Joined: 10 Jun 2008
Posts: 136
Location: Northampton

PostPosted: Tue Jun 02, 2009 9:56 pm    Post subject: Reply with quote

rings was my first thought but then the car appears to be running really well still. secondly the smoke doesnt smell anything like exhaust fumes.

dont suppose anyone can tell me what the oil filler caps on the light 12's are like? i'm almost certain that the one we have lost is not an original one.

do they have some sort of breather in?
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Timstopp



Joined: 16 Oct 2008
Posts: 95
Location: colchester, essex

PostPosted: Wed Jun 03, 2009 3:50 pm    Post subject: Reply with quote

I just had exactly the same in my 34 Wolseley, smoke coming into car on load sometimes and under car. The smoke smelt slightly oily but not like exhaust because it was caused by piston blowby due to worn or broken piston ring/rings. It is a mixture of unburnt gases and oil vapour. Indeed the pressure caused by this blowby probably caused your oil filler cap to blow off!
It was quite easy to diagnose with a compression tester, and I had a broken ring (see photo below). It took me about 4 hours to replace and now - no smoke!

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Wolseley Nine 1934 Morris 8 tourer 1936
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Timstopp



Joined: 16 Oct 2008
Posts: 95
Location: colchester, essex

PostPosted: Wed Jun 03, 2009 3:52 pm    Post subject: Reply with quote

Sorry, meant to say mine ran fine before (or so I thought), but now has extra power- not a lot, but some
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Wolseley Nine 1934 Morris 8 tourer 1936
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Nic Jarman



Joined: 05 Oct 2008
Posts: 1035
Location: Stoke by Clare, Suffolk

PostPosted: Sun Jun 07, 2009 12:54 pm    Post subject: Reply with quote

Hi Mid, nice web site.
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