Thanks for the info. It seems that the best guess out there is that these engines use 25 micron filters. I'll send the spare filter in my trunk out for them to look at. It may take a couple of weeks, considering I will be on vacation next week.
Everything Hy-Pro sells is made in their factory in Fishers Indiana. They may end up being expensive, but it can't hurt to ask. I went through their distributor training last year when we were working on a national contract between my former employer and Hy-Pro. I have a strong engineering background (the hands on type) and was impressed with their facilities. I was also impressed with their product when we put it in service. It did exactly what they said it would.
They warned up ahead of time that after installing their filter we would have a period where we were going to go through filters faster. Sure enough we did. Once the filters got the previously dirty systems cleaned up the usage rate went down. The filters take out 99.5% of the particles for the size they are rated at and their dualglass G7 (or are they up to version 8?) material holds about 4x more dirt than a paper filter. They cost about double a paper filter, but clean better and hold 4X more dirt. The question is how much will they charge to make some. If I get them going I will have them up on my site,
www.FryerPower.com.
-Jim