One of the issues with doing the pings is figuring out what pistons
are in the car. They are flat top pistons that just have 0.02 and an
"v" shaped arrow mark at the edge of the piston pointing towards the
front of the engine. He has no idea if they are 3, 4 or 5 ring. Even
if the pistons are pulled and we know how many rings they have is
there any way to figure out what rings will fit correctly? Oh, and a
ring job can be done in a 948 without removing the engine right
(fingers crossed)?
Greg
On Fri, Jul 1, 2011 at 1:09 PM, Jim Seippel <aseippel@austin.rr.com> wrote:
> Compression comes from the top rings on the pistons. The bottom ring is the
> oil control ring. You can have good compression and have bad rings. Engines
> using oil will sometime have great compression because the oil provide a
> better seal for the compression rings.
>
> If you replace the rings, you need to clean the ring grooves on the
pistons,
> hone the cylinder walls, and stagger the rings. There will be some oil
usage
> until the rings are seated. Oil consumption from new rings should disappear
> after 500-1000 miles.
>
> Smoke from valve stem seals usually occurs when the engine is first started
> and disappears after the engine is run for a few minutes. The smoke comes
> from oil running down the valve stem after the engine is stopped or after a
> downshift where the throttle is closed and the oil is sucked down the valve
> stems. If the valve to valve guide clearance is correct and the valve stem
> seals are OK it will likely be a ring issue.
>
> The above answer is based on a stock 948 that is using oil. A later model
> that is equipped with a PCV valve can suck oil it out of the engine if the
> PCV valve is not working correctly resulting in oil smoke.
>
> Also, you need to make sure the oil is good. If you have had a really rich
> running engine, you could have gasoline contaminated oil which will leak
> past the rings. Pull the dipstick and smell the oil, if you don't smell
> gasoline, you will probably have to re-ring the engine.
>
> Jim
>
>
> -----Original Message-----
> From: spridgets-bounces@autox.team.net
> [mailto:spridgets-bounces@autox.team.net] On Behalf Of Gregory Groiss
> Sent: Friday, July 01, 2011 11:05 AM
> To: spridgets@autox.team.net; ROBERT MANIACI
> Subject: [Spridgets] 948 With A Bad Smoking Problem
>
> Hello All,
>
> I am posting this for Bob Maniaci. He's tried to post it twice but I
> never saw it show up on the list.....
>
> Hey Guys
> I'll run the scenario by you guys and maybe someone can help. I bought
> my wife a '59
> 948cc bugeye for her b'day, car came from Fla. via Texas. The bugeye
> was blowing alot
> of smoke and oil coming out of the exhaust. I got a new 12G295 head and had
> new
> valves(3 angle grind)springs, bronze guides, and seals installed, Greg
> Groiss and myself
> removed the old head installed the new one( and found out that the
> bugeye has .020 flat
> top pistons)after installation 3 we did another compression test and
> came out w/ the
> following #'s cyl.#1 160, #2 155, #3 150, #4 150 reinstalld the plugs
> and fired her up.
> Immediately a plume of smoke shot out of the exhaust and got
> progressively worse. Is it
> possible the smoke is from residual oil in the exhaust. or is it
> possible w/even those
> compression #'s I have ring problem or something else I'm missing? If
> it's the oil in the
> exhaust pipe/muffler is there a way to to clear it without running the
> car and having it
> look like J. Bond switching on the smoke? (LIke seafoam) Any hlp or insight
> is
> appreciated
> _______________________________________________
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