Poulan 42 cc conversion with magneto?
 

Good evening.
Quick question about poulan...
Somebody told me that poulan 42 cc have a magneto mounted on the plastic case.
Is there a way to go other then electronic ignition?Say if i want to keep original magneto?
Though will ask before i buy the saw:eek:

Thanks.
Mitty

RE: Poulan 42 cc conversion with magneto?
 

The 42cc Poulan has the mount for the magneto coil on the case of the saw. There is no practical way of monting the coil to the engine head. I converted mine to an electronic ignition and it runs great

Armand

RE: Poulan 42 cc conversion with magneto?
 

Did anyone ever figure out a way to use the magneto ignition on the Poulan 42cc? Perhaps a portion of the case could be left intact for the purpose of holding the coil like in its intended configuration. I had a couple of these engines given to me and would love to find a way of using them in a plane without having to buy an electronic ignition.

RE: Poulan 42 cc conversion with magneto?
 

av8tor1977 has one running on gas/glow, cheaper than electric ignition and easy to work with apparently, i'm sure he'll chime in.

RE: Poulan 42 cc conversion with magneto?
 

Yep, Poulan 42cc on Gas/Glow on my Giant Stik. Has a smoke system, plenty of vertical. You can haul it straight up after a short take off roll. Many fun flights with it.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

What's the thread size of the crankshaft on this Poulan 42cc? If I went with the gas/glow route, I would remove the flywheel and then what kind of prop adapter would I need? I know I would need the glow plug adapter and the fuel mixture. Am I overlooking anything to get it going this way?

RE: Poulan 42 cc conversion with magneto?
 

Sorry but I don't remember what the thread size was on mine.

You can either make a glow plug adapter out of an old spark plug, or you can buy them for around 10 bucks or less from either Horizon Hobby or CH Igntions. You need a prop hub for use with electronic ignition. Another way is to take a hole saw and cut the center of the magneto out. You can then use this center piece, and a prop hub meant for use with a magneto. CH-Ignitions and others sell the prop hubs.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

Av8TOR: Do you use on-board glow on that plane? Capt,n

RE: Poulan 42 cc conversion with magneto?
 

No. Out of my five airplanes running Gas/Glow, I only put onboard glow on the Super Tiger .90. I'm thinking about putting a normal size carb on that engine instead of the huge one I put on it at first, and taking out the onboard glow. The engine makes really good power with the big carb on it, but it won't idle as slow as I want, even with the butterfly completely closed.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

Hey Av8tor, what is your gas/glow mix formula? I have a guy locally that wants an engine to run like that. I have a 23.6cc Echo for him. What carb do you run and what are the tuning issues? By the way have you done the twin yet?

Tim

RE: Poulan 42 cc conversion with magneto?
 

Hi Tim,

It's two parts of high test gasoline to one part of 10% oil, 10% nitro glow fuel. The trick is finding the glow fuel, even though all the major manufacturers make it. It's often called Glow Fuel for Large Super Tiger Engines. The Echo 23.6cc seems to run particularly nice on it. In very few cases, one needs to raise the lever in the fuel regulator just a touch to increase fuel flow. Other than that, you just open the needles about a half turn or so more than normal, and then fine tune as normal. The engine will like the idle mix a touch richer than we normally set the gassers.

Funny you should mention the twin. I built it some time ago, and it runs great. But just a couple of days ago I pulled the Gas/Glow Poulan 42cc off my Giant Stik and installed the twin. Test flight as soon as I can get around to it..... Man, that engine runs as smooth as glass. If you set a glass of "liquid refreshment" on the test stand with it running, it doesn't even shake the beer... whoops, I mean liquid. I also have it set up on Gas/Glow.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

No engine shakes on a fairly heavy test stand. When you get same engine on a fuse with no wing...then you can really tell how smooth a engine is! Capt,n

RE: Poulan 42 cc conversion with magneto?
 

Well, it doesn't shake on the airplane either. It's much smoother than the 42cc single that was on the plane, and I thought it was pretty smooth for a "thumper".

Tim, just happened to think you might have been referring to the 62cc twin. I've looked it over and made plans several times, but I still haven't gotten around to finishing that one. One of these days soon I hope...

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

Yep that is the one I was talking about. As for the different engines having the shakes, any engine of good size will shake when the fuselage has no wings. I have seen many times someone start up their giant scale plane without wings. Amazing how a single or twin engine can violently shake the fuselage around. Put the wings on and it is very smooth. Just my .02.

RE: Poulan 42 cc conversion with magneto?
 

Yeah, it's really not recommended, nor a good idea to start a plane without the wings. Puts the whole fuselage and everything on it/in it under a lot of stress.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

Bought an 18" Poulan chainsaw with a 40cc engine. Does anyone know if there is a big difference between the 40cc and 42cc engine? Doesn't make sense to me that they would build a new engine for 2cc's. Thanks.

RE: Poulan 42 cc conversion with magneto?
 

Not sure enough to say John, but I have a Poulan 36cc that is externally virtually identical to my 42cc.

Incidentally, the 46cc is a little harder to convert because of it's intake manifold configuration, but it's a lighter and more powerful engine. Something to keep in mind when shopping Poulans... Having said that, I've still gotten very good use out of my Poulan 42cc.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

What does a Poulans come in. I have been looking for one for some time now with no luck.

and What twin are you talking about and how hard are they to come by?

Paul

RE: Poulan 42 cc conversion with magneto?
 

The Poulans we've mentioned come in Poulan Chain Saws. I'm not sure if they are used in other branded equipment or not.

The twin I spoke of is one I made using a crankcase that Keith at BME engines was selling. They are no longer available. The other twin is a 62cc model out of an Echo Chain saw. No longer made and very difficult to find.

AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

Well that would be my luck. I want a twin. jus for fun

RE: Poulan 42 cc conversion with magneto?
 

hi, im in the middle of making magneeto adapters for all poulan engines that dont have the ignition on the engine itself.

RE: Poulan 42 cc conversion with magneto?
 

Ellas1, could you please show how you make the adapter for the magneto? Thanks.

RE: Poulan 42 cc conversion with magneto?
 

sur but not ready to send pics yet, almost there, i will send you once it is complete. its experimental once its on my engine and it runs (which it will) i will send you pics.
happy holidays.
john.

RE: Poulan 42 cc conversion with magneto?
 

You can find Poulan engines in sears chain saws. Lots of them! Captr,n

RE: Poulan 42 cc conversion with magneto?
 

Here's my attempt at converting this Poulan 42cc using a portion of the saw case. This way, I keep the engine, flywheel, and magneto in it's proper position. I still have to get a prop hub and mount it to some sort of test stand. I think more trimming can be done to the case near the "chain oil" portion of the saw case under the magneto. However, I won't do any more trimming until I actually get it running with a prop. I'm not sure how much I can trim away around where the magneto mounts, because I'm afraid of weakening this area. I'm not concerned with saving every last ounce of weight on this engine right now. My goal is to simply convert it to an airplane engine using the original ignition. If anyone has ideas or comments on my approach to this conversion, please let me know.

RE: Poulan 42 cc conversion with magneto?
 

Sorry to say, but I really think you should spring for electronic ignition or go Gas/Glow. I felt my 42cc Poulan was rather heavy even on Gas/Glow. I'm afraid yours is going to be quite heavy and bulky.

The cost has come down on ignition systems. Check www.ch-ignitions.com

Good luck,
AV8TOR

RE: Poulan 42 cc conversion with magneto?
 

I would like to use the stock muffler. How do I take it apart and gut it? Do I need to drill outlet holes in the muffler for the exhaust and if so, how many and what size?

RE: Poulan 42 cc conversion with magneto?
 

If you are planning on using the same carb. I wouldn't modify it to much,
especially if you have a one needle carb. or limiters on it.
You will run out of adjustment in a hurry.

Being a chain saw the mufflers aren't all that bad.
A lot of mufflers have a screen over the outlet.
Try removing that and go from there.

Your muffler looks sealed and can't easly be opened and resealed.

RE: Poulan 42 cc conversion with magneto?
 

I finished up my 42cc conversion and was able to keep the magneto ignition by keeping just enough of the saw case to keep the coil in the proper position. I did a little more trimming to the case since I posted the photos. I’ve test run it twice on a test stand and it runs and sounds great. I have not tached it though. However, it is quite heavy as I did not trim the flywheel or do any of the typical things to loose weight. It has the 11.11mm carb and stock chainsaw muffler. I mounted it to the plane that used to have the flywheel/magneto Homelite 30cc and after adding 5 ounces of tailweight to get it to balance, it came out 2 pounds heavier than with the Homey. I still need to test run it and tach it on the airplane, and if satisfied, I’ll try flying it. However, I’m thinking that I may go with the gas/glow setup. How much weight could I feasibly loose by doing this? Is it possible to get it down to what the flywheel Homelite 30cc weighs? If so, I could remove the added 5 ounces of tail weight. I’m thinking that the portion of the saw case I kept weighs around 5 or 6 ounces also. Does anyone know how much the flywheel/coil/spark plug assembly weighs on a Poulan 42cc? Obviously, what I’m trying to do is replace the 30cc with the 42cc for more power and keep my flying weight the same or very close. I guess I need to order a glow plug adapter, an OS four stroke plug, and try to get some 10/10 glow fuel. I hate to buy a gallon of 10/10 since I have 4 unopened gallons of Omega 15% already, but if I have to, I will. Am I forgetting anything else?

RE: Poulan 42 cc conversion with magneto?
 

Well she's not going to win any beauty prize, but should work OK. I guess you noticed that quite a lot of support is needed to stop the coil being attracted to the magnets while it's running - so you can't hack too much away there.

;)

RE: Poulan 42 cc conversion with magneto?
 

You're right, I did see movement in the coil mount as I rotated the magnets past, so I secured it with a steel zip tie around the coil mount and around the back side of the muffler. Now, there is no movement when I rotate the flywheel. I'll run it a bit on the ground to make sure everything is holding up OK before I fly it. Also, I don't think it would be that hard to replace the hacked up saw portion with an aluminum bracket to hold the coil. I think it could be made with small pieces of aluminum L channel to mount the coil in the exact position. I may still pursue this if I don't go the gas/glow route.

RE: Poulan 42 cc conversion with magneto?
 

The alloy channel route is how the coil is fitted to my McCulloch. Looks quite professional with the corners trimmed and small capheads holding it all together.

RE: Poulan 42 cc conversion with magneto?
 

Hi plasticmaster, if you can get some methanol try to mix one part methanol with 2 parts 15%nitro glow fuel this should give you a 10% nnitro mixture as for oil if its on a 18% oil content you'll probably end up in the 12% range so :Dprobably your mixture will be a 10/12 glow fuel which once you mix with 2 parts gasoline it will give you a 3.3% nitro and a 4% oil content, so go ahead and make a samll batch and try it on your 42 poulan as Gas/Glow mix with an OS 4F plug.:D

A 1 to1 mix of 15% glow fuel with methanol will give you a 7.5% nitro and 9% oil glow fuel that you can alsomix with 2 parts high octane gasoline and at the end you will have a 2.5% nitro and 3% oil which isn't bad for Gas/Glo fuel either.

RE: Poulan 42 cc conversion with magneto?
 

I'd mix up a batch of fuel using the 15% flow fuel.

Knowing that this isn't the ideal mix run it to see how is works.
Leave everything in place and give it a shot.

I did this on my first conversion and I knew I was on to something good.
It was a 32cc Mac that was discarded by another flyer when the EI went out.
It ran better on gas-glow than it ever did on EI.

RE: Poulan 42 cc conversion with magneto?
 

AV8TOR,
How much did your Big Stick weigh with the 42cc on gas/glow, ready to fly?

RE: Poulan 42 cc conversion with magneto?
 

Hey plasticmaster, regarding the stock muffler depending on how new it is it could have a catalyst. If you have "material" looking stuff inside, I would round up another muffler.

RE: Poulan 42 cc conversion with magneto?
 

I've only run the Poulan 42cc with the original muffler completely stock. I've taken it apart though and the exhaust goes into a hard metal "cage" with holes in it. This cage is also wrapped with the spark screen and the cage gives support when tightening the muffler to the engine. Once I get it running on gas/glow, I'll try running it again with the stock muffler and then with the spark screen removed. These are the only components inside the muffler shell.