Paul,
Thanks for the help. As near as I cal tell, the cover is not cracked.
I cleaned it thoroughly inside and out. No clogs. Although I did not examine
it closely for cracks. Seems like a pretty solid piece.
Agree with you on the valve cover vent. However, if I open up the vent
tube, the leak comes back big time even if the tappet cover is left hooked to
the carbs. Its basically the same leak as venting the tappet cover to
atmosphere.
When I first looked at the leak with the manifolds off, the cover was
fairly dry as was the block areas to the sides and top of the cover. The block
directly under the cover (for the full length of the gasket) looked like
someone had poured oil on it immediately before I looked at it (very shiny).
As I see it, I cannot remove my crankcase vacuum set up until I have
installed a fix that will stop the tappet cover leak. Normally I do not
disconnect PCV systems, but my only option as I see it is to install an earlier
tappet cover that was made before Leyland got so cheap that they couldn't
afford gasket channels. Any suggestions on which one to use ???? I was
thinking about MGA or 18G versions but I haven't seen either so I don't know if
they have the gasket channels or if the MGA version will fit.
Also, what about sealing off the tappet cover vents entirely and
venting only through the valve cover??? Any ideas on this ?? Don't know if
the oil drain holes in the head are big enough to allow venting.
Is this front tappet cover seal normally a problem (once its been
removed) ????
Thanks Again, Skip
'74 MGB
-----Original Message-----
From: Paul Hunt (T) [mailto:paul.hunt1@blueyonder.co.uk]
Sent: Wednesday, March 10, 2004 4:59
To: Christian, Wellner L. CIV COMNAVAIRSYSCOMPATUXENTRIVERMD AIR
4.1.1.4; MG Digest (E-mail)
Subject: Re: Desperate - Oil Leak From Front Tappet Cover
It definitely is not normal although it can be difficult to get a good seal.
Is it definitely coming from round the seal? Or is the cover cracked, the
crack being closed with the cover off but opening when tightened. Is the
breather pipe cracked? Is the pipe clear or has the gauze flame trap.oil
separator behind it got bunged up with solidified gunge?
I've found in the past that silicone sealant causes gaskets to get squeezed
out of position so I don't like it. Some also 'skin' very quickly in air,
in the time it takes to get a bead all the way round. I use Hermetite Red.
I realise you did it to try and cure a leak but unless you allow air in to
the rocker cover, either via the charcoal canister or a vented oil filler
cap if no canister, as well as sucking on it from the carbs, you will not
get adequate ventilation and in most cases condensation will build up
causing internal corrosion and that creamy scum on the oil filler cap. If
the canister has been removed you should block off the rocker cover port and
replace the non-vented oil filler cap with a vented one as this filters the
air as well as restricting it.
PaulH.
----- Original Message -----
From: "Christian, Wellner L. CIV COMNAVAIRSYSCOMPATUXENTRIVERMD AIR 4.1.1.4"
<wellner.christian@navy.mil>
To: "MG Digest (E-mail)" <mgs@autox.team.net>
Sent: Tuesday, March 09, 2004 7:09 PM
Subject: Desperate - Oil Leak From Front Tappet Cover
> I have a 1974 MGB. Car has had a bad oil leak from the front tappet cover
> since I bought it. I sealed the valve cover vent and left the tappet
cover
> vent hooked to the carbs to pull a vacuum in the crankcase. This slowed
the
> leak by about 80 percent.
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