Thanks for the reply. From what I read on this website forum it sounds like Lister engines had a good market / following at one time. So what changed it, the foreign competition or federal regulations?

I am new to this group and to Lister. Stumbled on to Lister through this group and other sites when I was looking for  diesel Generator.  Really like the whole concept of these engines. So I actually bought a SR2 generator set. Being new, I have noticed that there are so many different types/ model engines: Why so many models HR SR ST LR and more?

The other thing I am wondering about is Monarch engines. I have seen Monarch discussed here but not in a lot of detail.  I also bought a Monarch generator set with SR2 in the model number. It looked pretty obvious that this was either a clone to the SR2 Lister or Monarch bought basic engine parts from Lister and made some external cast parts with the name of Monarch on them. Is Monarch a clone or a Lister with Monarch's name on it?

The reason I ask about the difference is because gaskets are the same and other parts are too. Except there is one big difference I do see. When I took of the side plate to access and clean out the oil sump on the Monarch and Lister, the oil supply tubing for the main bearings is different. The Lister has oil go through an oil filter then to 3 supply tubes feeding the 1st, 2nd and 3rd main bearing. The Monarch has oil go through a filter and then on to only 2 supply tubes feeding the middle main bearing and the main bearing at the flywheel.  No tubes to the Main bearing at the front closest to the governor.  I have 2 thought on it; the front main bearing is feed from the oil pump directly with out going to the filter first.  You can see in the casting that the oil pump exit tube is close to the front main bearing and maybe it was drilled further to connect with the main bearing. Second thought is that it gets oil from the governor side via splash, because that area holds a small puddle of oil due to the exit hole back to the sump is slightly higher than the puddle. Any thoughts?