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Rocker cover gaskets

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Alpine Daimler
Posts: 189
Joined: Thu Feb 18, 2016 2:17 pm
Location: A tad west of Hamburg on the Elbe River

Rocker cover gaskets

Post by Alpine Daimler »

Hello everyone,
Having removed the rocker covers, one of which leaked a little, I noticed the seals were rubber and 3mm thick, the replacement cork seals from the usual suppliers which I already have are noticeably thinner at 1,6mm. I am a little sceptical as to whether theses will effectively seal even when thoroughly cleaned and applied with blue Hylomar to the covers and only lightly greased on the side to the heads to enable easy and clean removal.
Looking on the old forum there is a discussion from a while back re the the pros and cons of rubber verses cork, any up to date information out there with regard to suppliers or even a need to fit rubber seals?
I shall check the mating surfaces with a straight edge before refitting to try and assertain the minimum depth of seal, cork or rubber, required.
Regards
Rob C.

Vortex O'Plinth
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Re: Rocker cover gaskets

Post by Vortex O'Plinth »

I've followed Russ Carpenter's practice and bonded cork gaskets to the rocker cover with Polyurethane adhesive. After applying the adhesive and fitting the gasket I rest the cover gasket side down on a piece of float glass while the adhesive cures. Russ claims that bonding the seal to the cover prevents the corners of the gasket pulling in and allowing leaks.

When the adhesive has cured I apply Blue Hylomar to the gasket face before refitting the cover. This has proved effective in preventing leaks. The PU adhesive is a much stronger bond than the Hylomar so subsequent removal is done by carefully breaking the Hylomar seal to the head. I have in fact reused cork gaskets fitted this way; I simply clean the gasket face and the head, apply fresh Hylomar to the cork and refit.
Nick

"Don't bother with the Air & Space Museum - there's nothing to see.......".

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Alpine Daimler
Posts: 189
Joined: Thu Feb 18, 2016 2:17 pm
Location: A tad west of Hamburg on the Elbe River

Re: Rocker cover gaskets

Post by Alpine Daimler »

Thank you Nick, that sounds like a good tip, I shall try that. I shall take a look around the motor factors and DIY stores over here and see what is on offer, the "Engine room" of Europe must have something somewhere!
Regards from an unseasonably warm Munich!
Rob C.

David S
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Joined: Sun Feb 21, 2016 9:23 am
Location: Forest of Dean

Re: Rocker cover gaskets

Post by David S »

Someone, somewhere, one day told me that the SP & V8 rocker cover gaskets are the same as an [unknown type of] Nissan.
It was a while ago but not so long that they'd be unavailable.
Does anyone know the type of Nissan? .... I just wonder how thick a that particular Nissan gasket is?

Or is this all useless information....!
be

Oh and by the way, I don't think you need any Hylomar on the bottom of the gasket, but that's just me and maybe not the best way.

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migray
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Re: Rocker cover gaskets

Post by migray »

According to the old forum:

Toyota Corolla 1600 1971-1976 fit perfectly

Don't know if that is much help though? Also discussion about using 3mm neoprene O ring material.

http://archive.dloc.co.uk/forum/topic.a ... C_ID=14393

Sydsmith
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Re: Rocker cover gaskets

Post by Sydsmith »

Some years ago a member of the old forum posted a solution to leaking rocker covers which I have used ever since and has never let me down, not a drop of oil has leaked out and the covers can be removed and refitted without having to fit a new gasket.

The solution is to carefully fit 3 mm "o" ring rubber into the grooves in the heads, having carefully cleaned the cover of all oil, start at the top and super glue the rubber into the groove, it sits on the top and must be kept tight all the way round, cut the join carefully and glue the end together of course this only works if you have the type of cover with grooves machined around the edge.

You need 1 meter of rubber for each cover which you can get on line or from any good motor factor.

Crossley Stephenson
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Joined: Wed Feb 10, 2016 9:15 pm
Location: Victoria, Australia

Re: Rocker cover gaskets

Post by Crossley Stephenson »

After ignoring the problem for far too long I have recently removed the rocker covers cleaned off the old gasket and the used 3mm neoprene 'rope'. After thoroughly cleaning both surfaces I used a smear of RTV in the groove of the covers before fitting the neoprene and allowing the RTV to 'dry' overnight before refitting the covers. So far no leaks and no whiff of burning oil as drops hit the exhaust.

Cheers
Michael

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Alpine Daimler
Posts: 189
Joined: Thu Feb 18, 2016 2:17 pm
Location: A tad west of Hamburg on the Elbe River

Re: Rocker cover gaskets

Post by Alpine Daimler »

I am going to go with Nicks suggestion as I now have the cork gaskets and PU adhesive. I should add that having cleaned the mating surfaces of the covers they reveal a machined groove of sorts, I am not sure if it is factory produced or a non spec afterthought as it appears incomplete, has "S" bends and an inconsistant depth, see pics.
The 3mm seal would appear to be also a good tip for which I am grateful and may give a go if the cork and glue process is not successful. The Toyota seal may well be what I have removed, appears to have slithered out of place on (over?) tightening, I shall investigate that aswell as it is a little thicker and when glued into place could be the best sealing method
Regards
Rob C
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Sydsmith
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Re: Rocker cover gaskets

Post by Sydsmith »

Rob that groove certainly does not look original or like mine perhaps as you suggest a mod. My grooves are even all round the edge of the covers.

There was a lengthy discussion on this subject on the old forum and some members did have their covers machines with a groove to solve the problem at the time.

Both my cars have the "O" ring material and never a drop of oil passes anywhere on the covers.

Clive
Posts: 19
Joined: Sat May 12, 2018 2:09 am
Location: Phoenix, USA

Re: Rocker cover gaskets

Post by Clive »

Rob,

I decided to make my own from the thickest cork gasket sheet I could get - 1/8th inch thick. Buying a sheet locally was cheaper than ordering them from the usuals, and I have enough to make a couple more (and lots to spare to make smaller gaskets).

The old ones used to leak at rear bottom corners. New ones don't leak!

Clive.

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