Bob

Thanks for update.

I was aware of most of this info but but did not share everything here on RCU as this is going to make it pretty hard for YS, Richard Verano, and other world wide distributators to sell their remaining stock without the availability of the new pump and knowledge of the introduction of a new and more powerfull YS DZ 175 CDI. This is a tuff situtation for both the consumer [who is having problems related to design] and the manufacture [who is trying to fix the problem without damaging his current product line].

All

Update on my returned engine from Richard.

I had 13 very perfect runs over the weekend when late Saturday I began having the same surging problems and by the end of the day could not get the engine to run at full throttle and the more I tried to adjust it out the worse it got. All of these runs were with 19x11, 30% LS, high volume fan between flights, 95 to 100 degree days, and no adjustment to the engine mixture prior to it running bad again. the exact same symptons as before, only this time it was at the 14 & 15 flight count!

Sunday morning I asked Ron Barr to bring to the field several other types of fuel including some 20% & reg 30%. No joy, same problem. I had received in Saturdays mail the new pump from Richard and was ready to pull the engine and put the new pump on when I decided to try one more thing even though I was convinced it was not going to be the problem. I had installed two new spark plugs in trying to trouble shoot the engine prior to sending it to Richard so I new the plug was new. Well, by now you guessed it! I changed the plug and the engine ran perfectly for five more flights Sunday.

So I am back on track with testing to see how many flights I can get with cooling between flights, running the 30% LS, & 19x11 prop. By the way, after running the 19.5x11.5 I am not happy with the running the 19x11 but will for the test. As soon as I get to 100 flights with no problems, I am going to switch to the 19.5x11.5 as I need to do this while we we still have at or near 100 degree days. Not sure if or when this will occur.

Does anyone have an alternate source number for the YS spark plug? Central charges $24 for a single plug plus shipping and handling. That's over $30 bucks a pop that in the open market should cost no more than $5 to $10 depending on quanity!!

Dick