Head Gasket orientation

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fillpoke
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Head Gasket orientation

Post by fillpoke »

Could anyone please tell me if the head gasket goes copper side up or down? Thanks.
bmcecosse
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Re: Head Gasket orientation

Post by bmcecosse »

I prefer copper side UP - and a thin wipe of grease over both sides before installation.
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alexmcguffie
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Re: Head Gasket orientation

Post by alexmcguffie »

Yep, copper side up too and grease. The grease will become a layer of carbon around the fire ring once the engine has been running, helping sealing. That's the theory at least...

This article from Mini Spares might be useful too:

http://www.minispares.com/article/Techn ... 945ed28986

Alex
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bmcecosse
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Re: Head Gasket orientation

Post by bmcecosse »

Don't be tempted to go beyond 44 ft lbf with the standard studs and nuts......whatever KC ( :roll: ) may say.......
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philthehill
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Re: Head Gasket orientation

Post by philthehill »

Personally I would never torque a standard/original/old 3/8" Minor cylinder head stud/nut any higher than the factory recommended 40 lb ft (5.5kg. m.) dry (no oil on either stud or nut).
You never know how brittle/fragile the stud is and there is no point in overdoing it as there is more chance of breaking or snapping the stud. They may even have been stretched when previously torqued down.
As important as the torque is - it is important to ensure that there is no raised metal around the stud where it screws into the block. This raised metal is caused by the stud pulling on the block threads and could cause problems with head and head gasket sealing. It is always best to remove the stud and with a counter sink put a slight countersink into the block making sure that no swarf or bits get into the cylinders or oil ways. I always use a high powered vacuum cleaner to suck away the swarf or bits when doing this operation. Clean away any residue not picked up by the vacuum cleaner - cleanliness is everything when rebuilding any part of an engine.
Last edited by philthehill on Mon Mar 03, 2014 12:51 pm, edited 1 time in total.

alexmcguffie
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Re: Head Gasket orientation

Post by alexmcguffie »

IMPORTANT NOTE

The torque figures in the Mini Spares link are for a 1275 lump. The factory figure for a 1098 is 40 lbs/ft.
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philthehill
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Re: Head Gasket orientation

Post by philthehill »

The cylinder head studs and nuts may have been changed to the higher tensile strength ones Pt No: CAM150 (long) and Cam151 (short) with flanged nuts Pt No: 51K1193B. These high tensile studs can be identified by either: a dimple in the top end, stamped with a 'Y' or '22' on their top end or have a tapered finish above the 3/8" UNF thread; if they have those features/markings it can be safely assumed that they are the later high tensile ones and can be torqued to 50lb ft (6.9kgf m). All others to 40lb ft.
The high tensile (Pt Nos above) studs and nuts are much better than the standard Minor ones and I would only use these on any standard or mildly tuned engine rebuild I do or alternatively use ARP extra high tensile steel bolts when building a high power engine. In my opinion old Minor cylinder studs/nuts are an unknown quantity and whilst they may be perfectly useable I prefer to fit the high tensile ones, you pays your money and takes your chance!!!
You should always have either a full set of standard or high tensile Minor cylinder head studs/nuts; DO NOT mix and match!!!!

bmcecosse
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Re: Head Gasket orientation

Post by bmcecosse »

The exact same studs were used on the original Cooper S engines - and were specified at 44 ft lbf. II've never had any bother with that setting. Yes - the dimple/Y/22 studs are better - but I would be loath to go above 44 - nor do I see any need to go higher. The later Mini engines are specified at 50 ft lbf - BUT with the later studs as Phil mentions - and with the flanged head nuts. Without a doubt these nuts are better - but I'm not convinced 50 ft lbf is necessary. And I agree -it is a good idea to slightly countersink the stud holes in the block - to make sure there is no raised metal there.
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