Why are there so many rumours about piston #3 on flat fours? why is it the one the breaks first??
-- Paul Soames
1973 1303 Beetle -
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#3 piston
Oct 07, 2003
4 Replies
1973 1303 Beetle -
It has had cooling problems by design.
It's the one with the least cooling air flow on the pre-doghouse (pre-71) fan shrouds. Best place for a CHT sensor. The doghouse style had the oil cooler tin moved so it didn't block #3. I think the dates are right, but not sure.
3 reasons.
1) less cooling air (or hotter cooling air) on non-doghouse engines
2) runs hotter due to exhaust restriction (heater box) 3) it's the last cylinder in the engine to get oil (it's the forward most cylinder, lowest oil pressure).it's the only cylinder with all 3 problems, so it runs hottest.
John Aircooled.Net Inc.
AND.................Every one I've seen as a short block says
" If #3 Piston is damaged , Warranty is void"
What happens is, If you time it too far advanced , it will blow a hole in #3 fairly quickly....................no matter how well, the rest of the installation is done. This is why Timing is so Crucial on the VW engine among other things.
Remove "YOURPANTIES" to reply MUADIB®
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Artificial Intelligence is no match for natural stupidity.
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