Re: Revmaster damage report

Jim Patillo

Hi Dave, 

Teflon “buttons” keep the rod pins in place from contacting the side walls, instead of relying on metal clips. Was there a really loud bang? 😮
That was one hell of an explosion. 


From: <> on behalf of Dave Dugas via <davedq2@...>
Sent: Friday, October 15, 2021 6:38:45 PM
To: <>
Subject: Re: [Q-List] Revmaster damage report
Hi Robert. 
I don't understand what a Teflon button is. I'll be looking for the connecting rod bolt to see if it broke or loosened up, when I get the case apart.

On Fri, Oct 15, 2021 at 9:07 PM, Robert Cringely
<bob@...> wrote:
My VW experience was back in the 70s and 80s when I rebuilt the engine in my $1300 KR-1 MANY times. It never failed or even hiccoughed, but I always wanted more power. 1600, 1835, then 2180 lasted 1100+ hours until the hangar roof failed in a storm, crushing my little KR. I used it one year to commute from Palo Alto to Van Nuys for a teaching job. Oh, to be young again...

Snapping back to reality, it's clear that you broke a rod bolt but I think the piston pin failed first. It's also gone, and from the shape of that little end I'd say the big end was still intact when the (now pinless) little end started smashing into the bottom of the piston. Either a circlip failed or a teflon button melted. Sometimes those teflon buttons aren't really teflon, which is why Steve Bennett wouldn't touch them

On Fri, Oct 15, 2021 at 5:11 PM Dave Dugas via <> wrote:
Here's pictures of the pieces from the #1 cylinder, along with a picture of the crankcase. A lot of aluminum material of various sizes also found in the sump when I removed the oil drain assembly from the bottom of the crankcase. I'm going to split the case, hoping to see what's left of the connecting rod bolt, which I think was what failed.

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