Just a quick question on Davis conversions>
While I am not a real novice at diesel engines, having several PAW's that I am familiar with, I recently picked up a couple of Davis conversion heads for an OS .25 LA and .40 LA. The instruction sheet that came with the heads recommended breaking in the engines (on glow fuel) before replacing the head with the diesel version. Since both of my OS's have never been run, I am wondering if this is really necessary? I can only guess that it has something to do with achieving a good seal between piston and cylinder before replacing the head and using diesel fuel. Am I wrong here?

Thanks...............

I would run at least a couple of tanks of glow on the bench you will get a feel for the engines they do have their own personalities. I have done it both ways no glow break in
and direct with Bobs heads, Its easier if you go with the glow run first also if you just put on the dieselhead without a glow run the break in will take a lot longer, Mr Davis states this for a reason 30+ years of making them. There is a big difference between the classics such as PAW and the modern schnuerle ported engines OS . TTs.STs etc each is fine in its own right I have both martin

I forgot which engine did not get a glow break in but to get it running the compression screw was all the way down and still missing after a few tanks the compression picked up and I could back off the compression screw since, yes the seal got better