From what I understand this is the same basic engine as the Brison 2.4. Is there anyone out there that offers a conversion for this saw engine? I have an old Dolmar (Makita) PS 401 that gets very little use as a chainsaw. I am willing to sacrifice this as an aircraft engine in lieu of my Husq 335xpt, Stihl 034, and Husq 272 xp.

What is involved in converting this engine? I have never done a conversion, but am very good at taking things apart! :-)

Take it apart, take the crank out, Push the bearings out or cover them with some duct tape...cut or grind off all the extra casting until you just have the round part of the case...Make a flat plate that uses the case bolts to hold it together..You can drill out the case bolts with a .194 drill and use 10-32 bolts all the way through the new back plate to hold it together..cut off the rear straight part of the crank a little above flush with the rear crank seal...Re install the crank..Make a new prop hub with a magnet in it and a bracket for a Hall sensor for the CD ignition....Picture is a 4.2 Sachs chainsaw conversion, same idea except the ignition is inside the mount...

Poulan 60

Hey Ralf...how good does that Poulan 60cc engine run. Looks Nice!!! Capt,n

Ran great when it was here, Maybe Alan has run it in his plane ?

Ralph, you are a beast! ... and I mean that in the nicest way! You directions sound reasonable, though I am sure this will make a lot more sense as I start getting the thing torn down.

Looks like I am going to need to acquire or make some parts to make this thing work. Will I need to buy an ignition system for it? Where? From whom? How much?

How would this compare to a G-38 or G-45 in performance? Weight?

Needless to say, those pics you posted of your conversions look awesome!

Hey RCIGN.....did you get a new computer.? You see to be doing more photos. Very Nice. Keep up the good work. Capt,n

I found my long lost digital camera and figured out how to use it
The Sky's the limit ........
Hgiles....Stronger and lighter than a G38...C&H can set you up with an igntion...[8D]

My Poulan 60cc (shown above in Ralph's posting) converted by RCIGN1 runs great! Have one mounted in a Jack Devine P-40 but it has not flown as of yet. The builder is not yet ready to make the maiden flight yet. We have run about one tank of gas through it but I can't remember what rpm's were were getting. He is running a three bladed prop on it. I'll get rpm and prop size and post here soon.

Thanks for the reply Birddog.....how did you get that online name? Kinda Neat. Did they make a Birddog airplane. Maybe a trainer??? Take care Capt,n

I've been in love with the Cessna L-19 Birddog ever since I was a kid and the name just seemed to work for me. I just sold a 1/4th scale Birddog with one of Ralph's converted G38's on the nose here on RCU.

I have a Sachs model 102 that is also a 40cc saw. I was disappointed when I took it apart to find it has roller bearings. The cylinder is almost identical to the one on my Brison 2.4. The bearing on the bottom end of the rod is uncaged rollers. I have thought about putting a ball bearing in the mount at the rear to deal with the side thrust. Would this be a workable solution, or is there a better way to deal with this?

Thanks,
Dean

You may be able to install a thrust washer? Ask RCIGN....If anyone knows ...its him. He is the man!!! Capt,n

My Dolmar ps401

is the rod 2-piece with bolts holding it together or one piece?

a ball bearing to take thrust load would be better at the front...BUT all the old quadras and curent US engines 35-42cc engines get by just fine with rollers on both end of the crank and (at least on the quadra) a brass/bronze thrust washer.


dave

Dave,
Here is a pic of the rod, crankshaft, and the twelve rollers that make up the lower rod bearing. It might be possible to put the bearing on the front. It could be installed in the plate that also would carry the timing ring. The crank even has a shoulder on it that the bearing could ride against. The smaller portion of the crank measures .500 so a bearing should be easy to find.

Dean