Valley Gasket

bodger · Post by **bodger** » Mon Apr 25, 2011 8:04 pm

whats best , TIN or COMPOSITE .. and wit the later does it still need gasket goo on the water ways at each end ??

thankyou All .. keith

RoverP6B · Post by **RoverP6B** » Mon Apr 25, 2011 9:07 pm

Hello Keith,

Ideally it comes down to what heads and gaskets you are using. If you have 10 bolt heads or 14 bolt that have been shaved to give 28cc combustion chambers and composite head gaskets are used, then a tin valley gasket is the correct one.

If you have 14 bolt heads with their original 36cc combustion chambers and composite head gaskets fitted, then a composite valley gasket is the better choice.

I have not used a composite valley gasket, so I can't advice on the use of a sealant, but...I would be inclined to think that some should be used.

Ron.

ChrisJC · Post by **ChrisJC** » Tue Apr 26, 2011 6:59 am

I would always go composite now, but with the old non-stretch head bolts (remembering to retorque them after 500 miles)

You just need the heads skimmed appropriately because of the extra thickness.

Chris.

bodger · Post by **bodger** » Tue Apr 26, 2011 7:15 am

thankyou Guys .. i have 14 bolt heads with the outers not tightened fully ( nothing done to the heads )
with composite head gaskets as i'm using 10.5:1 pistons

its only the VALLEY gasket i'm changing i was wondering if i was using the right one ..?

DaveEFI · Post by **DaveEFI** » Tue Apr 26, 2011 7:58 am

bodger wrote:thankyou Guys .. i have 14 bolt heads with the outers not tightened fully ( nothing done to the heads )
with composite head gaskets as i'm using 10.5:1 pistons

its only the VALLEY gasket i'm changing i was wondering if i was using the right one ..?

Don't think there is a composite one. The choice is plated steel (bright) or some form of plastic coated steel (black).

On the aftermarket at least there are also two designs of the black one. One is the same pressing as the bright one, one has a slightly different profile round the ports. Make sure it actually fits properly and doesn't overlap the ports. I recently went through three from a South London Land Rover specialist, and they were all wrong. Eventually bought one from a main dealer - at 28 quid

- and that was fine. The rubber seals may be different too between black and bright.

I did use Hylomar on the black gasket round the water ports. Dunno if it was needed.

bodger · Post by **bodger** » Tue Apr 26, 2011 5:02 pm

Thankyou Dave

i got a shiny on in the end , i was told the black ones are just the same inside but have a coating to reduce the " tinny" sound the odler ones make ... ??????

baffles me , i have never heard mine make a noise ?

mgbv8 · Post by **mgbv8** » Tue Apr 26, 2011 6:50 pm

The comp valley gaskets are just tin ones with a nice coating on them. The coating itself does compress and makes a nice seal anyway. I've changed these at the track a few times and fitted them dry with no issues. Come to think of it. The last coated valley gasket was re-used 5 times and didnt leak

Although I have to admit to brushing on a thin smear of red hermetite to all the mating faces when I fit a new one.

These gaskets re just as strong as the old tin ones as I found out recently when I had a bit of a backfire

DEVONMAN · Post by **DEVONMAN** » Tue Apr 26, 2011 8:00 pm

bodger wrote:Thankyou Dave

i got a shiny on in the end , i was told the black ones are just the same inside but have a coating to reduce the " tinny" sound the odler ones make ... ??????

baffles me , i have never heard mine make a noise ?

When they first used this engine in a Rover (P5) they put a flat pillow of sound absorbing material between the gasket and the underside of the inlet manifold. This made the engine sound quieter and maybe that's what they were on about.
Maybe it also helped to keep the carbs cooler????

Regards Denis

TVRleigh · Post by **TVRleigh** » Wed Apr 27, 2011 12:04 pm

mgbv8 wrote:The comp valley gaskets are just tin ones with a nice coating on them. The coating itself does compress and makes a nice seal anyway. I've changed these at the track a few times and fitted them dry with no issues. Come to think of it. The last coated valley gasket was re-used 5 times and didnt leak

Although I have to admit to brushing on a thin smear of red hermetite to all the mating faces when I fit a new one.

These gaskets re just as strong as the old tin ones as I found out recently when I had a bit of a backfire

There are two types of these one as pictured about and a cheaper one that has more of a cardboard black finish.

I've also fitted the one above dry without problems. it shoud have 'G' at the end of the part code.

mgbv8 · Post by **mgbv8** » Wed Apr 27, 2011 5:49 pm

These are the ones from RS and have a sort of neoprene coating..

bodger · Post by **bodger** » Wed Apr 27, 2011 7:10 pm

thankyou once again everyone .. lots of good info ...all logged for future reference

bigaldart · Post by **bigaldart** » Mon May 02, 2011 6:35 pm

TVRLeigh,

That gasket looks familiar, a few years ago we put a stock early motor under our blower, stock pistons just to make a pass at the end of the season, we made it to about 100 ft and that's what the gasket looked like although slightly tighter moulded to the intake lol. Pulled the heads in the pits and as each piston came out there was a tinkle as the ring lands fell off! Oops, gasket didn't leak though.

Alan

mgbv8 · Post by **mgbv8** » Mon May 02, 2011 7:59 pm

That was my gasket Al ??

I was doing an ign spark strength test while the engine was idling. I put the plug onto the rocker cover to test it and as I lifted it off the plug spark jumped to the steel mesh in one of my breathers and lit up the engine vapours

It was quite a loud bang that got a few folk around me in the pits