Rough engine due to sticking valve
Lefty
the engine roughness. Thanks for getting me on the right track.
However, be aware that the inner part of the guide retates within the
outer part. Point being, this will make it difficult to lap the stem
without removing the valve. This of course requires removal of the
cylinder. My intentions at this point is to use an additive to perhaps
clean up the valves somewhat.
I will point out that on one occasion on start up I had a dead spot
and had to move the prop by hand. As I was rushed to keep an
appointment, could not take the time to locate the cylinder. As I
could actually hear the air escaping, I now realize I had an exhaust
valve stuck open, could have easily idenified the cylinder. But this
could happen on any cylinder I suppose if it is due to the cooling
down of the cylinders.
Let me know your thoughts on this
Lefty
David McGirt
to the TW list, as he is my TW mechanic - well, part of a team of
mechanics.. ( Tim, Robert, and Bill ) Hehe
On 11/23/07 9:05 AM, "Lary King" <lk...@tacora.com> wrote:
> David,
> FYI, you will get air coming out on start with the "dead" cylinder as it is
> designed to do this with the lower cylinders porting air out with the exhaust
> valve open to assist with hydraulic lock issue. Only the lower 4 will do this
> and it is most noticeable when the air is low.
> I always use Marvel Mystery Oil to help with valve sticking. 1/2 gallon on
> every oil change keeps them nice and clean. Possibly the engine in question
> was operated on auto gas which eats up the exhaust valve guides. And yes the
> valve guide is a very complex assembly. Sticking with Russian engineering of
> as many parts as possible and still be able to work there are some 15 parts in
> each guide assembly.
> The best way to keep them in good order is to keep the oil clean and use MMO
> and do not let it sit for long periods. I have changed several cylinders with
> obvious corrosion rings on the valve stems from prolonged sitting in one spot.
> Larry
>
> -----Original Message-----
> From: da...@mcgirt.net [mailto:da...@mcgirt.net]
> Sent: Thursday, November 22, 2007 9:01 PM
> To: Lary King
> Subject: Fw: [Yak52TW] Rough engine due to sticking valve
>
> Fyi
> Sent from my BlackBerry wireless handheld.
>
> -----Original Message-----
> From: Lefty <randm...@bellsouth.net>
>
> Date: Thu, 22 Nov 2007 17:41:20
> To:Yak 52 TW Owners Group <Yak-52-TW-O...@googlegroups.com>
> Subject: [Yak52TW] Rough engine due to sticking valve