I recently picked up a Bud Nosen P-51 with a Sachs 4.2 in it, for short money. The engine looks to have never been started (as the airplane was not quite finished). I've done my share of research online about the Sachs. I have not however come acroas anyone out there currently converting them to electronic ignition or even working on them for that matter. I have a shop full of DA's but I have a feeling I should hang onto this old girl and see if she can find a place in one of my 1/5 warbirds.

Any insights appreciated!

Milton's got your EI Conversion parts and is very helpful

http://rcextremepower.net/

What you have there is a engine that puts out great power and will last forever. A 22x12 prop on this for a warbird is idea. Once the engine is broke in (100 flights or so), you no longer need the spring starter. It hand starts very easy as long as the points are clean and adjusted right. These are great engines and will knock the socks off any new engine out there! Let me be the first to know if you decide to part with it! Paul

Thanks Jerry!

Paul, This is my understanding that these are bullet proof engines. It came on a Nosen Mustang that was never finished and I had just picked up some new Retracts for it when I came into a Ziroli Fibergalss mustang nearly complete. My dilemma is weather to mount up the 4.2 which is basically new and was almost free to me or bust open the bank and put a DA 100 inline in it which will undoubtedly make me smile. I have certainly owned some great older technology engines that were great, like G62's and GT80's, that started every time easily and ran great. Do you think the Sachs is enough engine to pull the Ziroli with authority? I have a G62 in a Byron AT-6 and I'm not disappointed with that but you do have to fly it. I think I've gotten a little jaded as I have some 35 & 40% IMAC stuff that skews your idea of what performance is. In fact I fly jets for a living and I realize how little we fly in the RC world is scale powered. When I flipped the prop through very briskly with a known good plug and the grounding circuit squared away...no spark. Is there much to opening her up and checking the mag etc?

This engine could have either a cdi magneto ignition or a points magneto ignition . The black wire coming out of the engine is the kill wire . It gets grounded to the engine to kill the engine , be sure it is not grounded when testing the ignition . If you have a point ignitiion it is possible that the points and condensor are the cause of no spark . If it is a cdi ignition the most likely cause of no spark is a failed coil or bad plug wire .
In either case it would be best to convert it to an electronic ignition . I would contact Bill Jennings at Bjs engine service or Adrian at CH ignitions for the conversion.
The 4.2 itself is literally indestructable and every bit as good as a G62 or any other 60 to 70cc engine . It is a heavier engine than the newer generation engines , but most warbirds need the nose weight anyway . I would run props such as Xoar 22x12 , 24 x10 or APC T6 racing prop to get that warbird speed .
anyway .

That's great info, as I did not find and schematics or diagrams as to what was lurking on that bell housing. I would like to get her fired up before committing and building around it for the Ziroli. I agree a conversion to EI is at a minimum going forward. I agree about the nose wieght, I always cringe just piling the lead on to a firewall!

I'm in Argentina at the moment but will pull her apart next Monday when I get home. Just familiarize myself and plane on shipping it out for conversion. Any guess and what I should budget for conversion? I only ask because if it were to be in the $200-300 range I would have to seriously consider a used DA 85 for high 4's.

Thanks again for for the insight!

I would think somewhere in the 150.00 range would be reasonable . RCextremepower can sell you a kit to install but you may need to do some light machining and fabrication for magnet and pickup mount . It may be worth a call to see what he can do for you .

Since you are used to flying an IMAC type 40% bird I would think that for you to be happy with that 4.2 in the P-51 it would have to weigh no more then 30 lbs. I have fallen into this myself, people give me very strange looks when I tell them my .60 powered 7 lb Super Kaos is a dog. But that is what happens when you get used to flying a 38-40 lb airplane with 90 lb of thrust.

I know!! I had a 1/3 scale Cub with a DA 100 on it and it was like crack! It was just so much more fun to fly, I really do like to fly scale, which is something not often seen at our flying fields. However, it's so nice to just be able to throw in another handful of throttle and defy gravity once in a while.

I have a Ziroli DC-3 in all FliteMetal which is the one airplane I intentionally did not overpower. I'm planning on doing this P-51 in Flitemetal as well and sub 30 lbs will likely be a stretch.

I was just down at Top Gun a couple of weeks ago and the Warbirds there were "well powered" and it was very cool (albeit not realistic) to watch them pull themselves skyward with little effort.