Best valve guide alloy?

I have a '87 Carrera and it sometimes smokes(blue oil smoke) for about a minute or two after start-up, usually after sitting for a few days or more. This started about 5,000 mi. ago ; it has 112,000mi on the orig. motor. My question is, should the problem be worn guides what is the ultimate alloy for replacement? One parts supplier advertises Beryllium Copper as the best for both valve guides and seats. Others say a Silica-Manganese Phosphate is best for guides and stock seats are OK. From what I've heard the factory Phosphor-Bronze guides are problematic; too soft and can't take the heat. Looking for longevity on daily driver here, what's best? Maybe oil is just seeping past the rings during long periods of sitting? Seems possible due to oil reservoir being higher than engine sump. One thing more, a brown deposit has always accumulated on the bumper near the exhaust; oil(Mobil 1)consumption is about 1 quart in 700mi umless it's driven more aggressively then it uses about 1 quart in 500mi. And it always smells like burning oil while idling at a stop but I don't see any smoke.

[This message has been edited by movin (edited 01-14-2001).]

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[This message has been edited by movin (edited 01-15-2001).]

[This message has been edited by movin (edited 01-15-2001).]

[This message has been edited by movin (edited 01-15-2001).]

The good news is that your valve guides aren't what's causing the smoke on startup. That's typically either an enrichened mixture (rare on a DME car, unless the engine is stone cold, which yours is) or possible oil seeping past your rings (more likely) or possibly condensation in your engine somewhere (which is most likely). My car has always smoked on startup (an '86).

As far as valve guides go: The chromed versions starting in '86 haven't given me any trouble yet (at 107K). I have heard of later cars still having problems though. This problem plagued the 3.2 series the most, I think.


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Mark Szabo
1986 911 Targa 3.2
1987 Escort 5-speed 1.9
The Porsche Owners Gallery

Originally posted by old_skul:
The good news is that your valve guides aren't what's causing the smoke on startup. That's typically either an enrichened mixture (rare on a DME car, unless the engine is stone cold, which yours is) or possible oil seeping past your rings (more likely) or possibly condensation in your engine somewhere (which is most likely). My car has always smoked on startup (an '86).

As far as valve guides go: The chromed versions starting in '86 haven't given me any trouble yet (at 107K). I have heard of later cars still having problems though. This problem plagued the 3.2 series the most, I think.

The smoke is oil burning, and it seems to happen after sitting for a few days or more. Maybe oil is seeping from the reservoir to the sump up to the cylinder level? Could that could explain the start-up smoke? Why would it just start doing this 5,000mi ago? Bad rings? Would a power chip cause an overly rich mix and lead to wearing out of the cylinder and rings?

Apparently the boxer engine gets oil in the cylinder when it sits. From the sump. Normal. I think you'll find that the oil smoke cloud happens sometimes, and at other times does not. Normal.

My car runs pretty rich during startup, though CIS is different. the smoke looks bluish in the mornings, but is mostly white, gas/condensation smoke. And there's a lot of it. normal, but I wish I could turn down the choke. I may try fidding with the warm up regulator some day.

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'83 SC