1990 964

[Gustaf 911]

Just wondering has anyone had experience with replacing valve covers on A 1990 964, I see there's some after market billet ones on the market, just wondering if there's been any issue with them, as my original ones are driving me nuts.

Cheers Gus

[twood]

The early valve covers are made of magnesium and they corrode. I looked at the billet ones but at the time they were just too expensive, The later OEM 964 valve covers are aluminium and i replaced mine with those and they seem to be fine. I liked the billet covers and they are probably better but I could not justify the cost.

[Tit]

I put on the later aluminium covers. They seem to work ok.  I still have some weepingweeping (a drop or two a week) but I think that's coming from higher than the valve covers. 

The early valve covers are made of magnesium and they corrode. I looked at the billet ones but at the time they were just too expensive, The later OEM 964 valve covers are aluminium and i replaced mine with those and they seem to be fine. I liked the billet covers and they are probably better but I could not justify the cost.

[tomo]

A bit of Info:

Advantages of billet:

• Cost effective in low quantities 
• High degree of precision 
• Very short lead times
• Structurally the parts are stronger

Disadvantages of billet:

• Costs increase as quantities increase 
• Some designs are not cost effective to machine
• Some designs cannot be machined from solid billet

Advantages of Casting:

• Cost effective at low quantities 
• Can produce parts of all sizes
• Capable of producing uniquely shaped parts 

Disadvantages of Casting:

• Labor intensive 
• Reduced dimensional accuracy compared to billet
• Rough surface finish 
• Imperfections or defects in the metal 

[Tit]

http://m.ebay.com/itm/380521238907?_mwBanner=1

[Mike D'Silva]

Gus

have you tried a new gasket kit with new washers and nuts? When i did my blue 964, i had the original magnesium covers blasted, coated and used a new kit with everything replaced. 

The previous service centre had put sealant on everything! threads, under the washers, etc...

With the new gasket kit, and the correct torque setting, I was lucky to not have any leaks... But I sold the car a few months later.. only did 2000kms since the new gasket kit went in...