Micro CoGen.

Prime movers, diesel and gas engines => Listeroid/Petteroid/Clones => Topic started by: veggie on November 07, 2009, 08:49:44 PM

Title: Compression adjusting nut ....or plug it?
Post by: veggie on November 07, 2009, 08:49:44 PM

I hope I'm not opening up an old debate here but I need some opinions on the compression adjuster.
My 6/1 has the adjuster, but I also bought a Plug for the orifice which will fix my compression ratio at 18:1 (I think).

Intended running conditions:
======================
Load: Constant (2.5 - 3kw)
Fuel : WVO or WVO Blend
Location: Indoor Constant 55+ degf

Question: Do I need the compression adjuster ?  Pros? cons?   ( If it's really not necessary, I'd rather just plug it)

Cheers,
Veggie
Title: Re: Compression adjusting nut ....or plug it?
Post by: BruceM on November 07, 2009, 11:35:54 PM
Lister dropped the adjuster in their later years of production; I think consensus is that it was just an early marketing (and patent) gimmick.

I concur with Jens, blow off the adjuster, but get a glow plug.  Makes cold weather starting the same as summer.

Title: Re: Compression adjusting nut ....or plug it?
Post by: Crofter on November 08, 2009, 09:11:21 AM
I am starting my 10-1 now in freezing temperature and it would be difficult or impossible (for me) without the glow plug. A bit of additional compression does not have the same significance to a diesel engine as it would to a gas engine in regard to creation of higher peak cylinder pressures.

If you are always starting at a controlled higher temperature the glow plug is not of importance but if you do wish to go to a plain COV eliminator plug you can easily use a different shim gasket pack to adjust your compression downwards slightly and perhaps a bit of experiment with injection timing should be done to match it best with your fuel and engine rpm and load since it is a combination of compression induced cylinder temperature and time of initial injectiion that controls the actual fuel ignition and crankshaft position when peak pressure occurs. My bet is that real compression ratios are not really as high in reality as the figures commonly kicked around for a listeroid.