6 replies to this topic

[Pat]

Hi all,

Are any of you familiar with glazed liner coursed by fully synthetic oil instead if mineral..

Have not dismantled the head/barrel yet, but some people has talked about glazed liner..
Im not using NOS pre-war iron cast rings, JP and the workshop confirmed steel rings.

cheers,

Edited by Pat, 26 July 2010 - 01:02 PM.

[Stork955]

Gday, no. Synthetic oil wont cause glazing on its own. What sort of bike are we talking about?


Cheers,

Stork

[jon v8]

Last time I had a glazed liners to deal with it was on a kubota 3cyl diesel running a generator on light load.The advice was to mist vinegar int the air intake whilst the engine was running on full load.It worked,the slubbering stopped within an hour of running and the engine went away - not to return.There is alot of talk about correct oil and running in proceedure etc,but modern oils to me can be so good at lubricating that they prevent running in that bores/rings need.
The old Deutz diesel advice of a handful of vim in the air intake on full load was a bit cruel to me....

[DAVETOM]

A few years ago, I worked with a guy who had been an engineer with the Williams F1 team during the Alan Jones era. To reduce blow-by and bed rings in, they used to sprinkle Talcum into the inlets, and watch the excess crankcase pressure disappear...
Must have been a brave guy who tried it first on a nice new F1 engine!

[Pat]

Thanks a lot for your replies!!

Yes, synth is "to good" > not running in..after ~50h trials riding. Instead spots at the liner / rings could have been glazed..
The plug gets sooty NOT wet after ~45min..just brush clean and contiou trialing..:-)
This spring I had perfect plug colour during 2d riding, as good coulour as my ZX6...

At the rebuild I was very eager to use modern rings because mineral oil is never any option just to get crap iron cast rings working.
...order a one of piston..BUT the workshop confirmed the rings from JP are ok...

Will test ride some days with mineral before I dismantle..AND order a new piston..

cheers,

Edited by Pat, 27 July 2010 - 08:39 AM.

[Stork955]

Gday, a black dry plug is fuel over-rich. This can cause oil consumption over a long time as it causes "bore wash". (Probably worn needle/needle jet). The fuel actually washes away the oil film on the bore and makes the rings wear prematurely. Iron rings are fine, the secret as you say is in the run-in. The first 10 minutes are the most crucial for any engine, it must be loaded to seat the rings properly. Engines running light loads also can do a similar thing like the generator above. Check your plug fouling issue first, it will be pointless doing any repair until this is OK.

Cheers,


Stork

[Pat]

Hi,
~25h trials riding after the switched to cheap mineral oil;

*identical ignition performance minute one-> 4h later, (before only ~30min couple of weeks ago..)
*plug is much less sooty, almost perfect
*oil drips from the crank case vent as it did this spring with synth oil. My interpretation is that now again a minor overpressure in the crank case occurs due to sealing oil ring as it should..
*nothing but oil has been changed:
-similar jets
-similar plug heat grade

Probably after ~75h tot the crap rings has starting to run in..
Cant wait to switch back to oil that do not fill the engine/pipe with dirt...

Cheers,