Hello,I have a McCulloch weedeater engine I would like to convert to R/C .Is there a do it youselfer out there who has pics and instructions on how I go about this?I know this question has probably been asked a thousand times but I am not haveing any luck searching forums....any help would be apprieciated...Thanks

These people sell a conversion kit.

http://home.att.net/~carrprecision/Page3.html

Go down to the McCulloch picture and study it carefully and compare with your engine. Call the guy on the phone and talk to him?

all you should need to convert this engine is a prop adapter. for the engine mount you can just go to the hardware store and get some nylon spacers the length you need, a stick of 10-32 allthread and some nyloc nuts, but this only works if you can get to the back side of the firewall... that style works well though... just go straight out 4 of the 5 back plate screw locations

if you can machine a prop adapter, it's not that complicated, just make the blank the shape you want, tap the smaller end to the threads on the crankshaft (I think it's 5/16 24) then drill and tap the large end for whatever size you want the bolt to attach the prop to be, you have to cut the crank where the threads start to make this work, but you can do that with a hacksaw or dremel or something...

A McCulloch with a clutch at the engine (Long shaft) has 3/8-24 threads. One with a short shaft is 5/16-24

It's been a few years but I (For some reason?) remember the back plate bolts as 10-24? All the bolts should be replaced anyway for they are torqx head self tapping screws. The head stips out easy and they break.

When taking an engine apart, the screws are coated with Loc-Tite and will be difficult to remove. A little heat applied with a propane torch seems to soften the Loc-Tite but be sure and not to melt any aluminum.

Got a Mac Mb29....Yardman has the same engine parts. http://www.rcuniverse.com/forum/tt.asp?forumid=92 Good luck Capt,n

I knew it was 10 something or other... (they only sell one size of #10 allthread if you can even find it) and it's been a few months since I did my conversion and I use all sorts of bolts at work... they all get mixed up in my head... I've assembled around 7 GM engines starting with longblocks, all LP/Gas and all '07 models going for certification... there's a few bolts here and there

none of the mac's I've torn apart (3) have had loctite on the threads, all have been the self taping torx bolts though which come out hard sometimes, I just used the stock 5th screw to hold the back plate on then mounted the engine to the firewall with the studs to seal it the rest of the way, seems to work fine...

one of these days I'll get pics of what I did with the flywheel, I just broke the fins off with pliers and sanded them down as even as I could, doesn't vibrate at all... didn't balance it either...

yeah, my only experience is with the older 28 and 32cc engines, which is what I assumed this topic to be about... not as powerful as I expected but it could be the fact that it's most likely tired (will get bowman rings sometime soon) it's been off the plane for a few months waiting for me to get enough ambition to tear into it and modify a few things...

The Mac 28/32 is not as powerful as you would think by looking at the ports. The timing is conservative. Try to prop them for 7000.

I have two 32's w/C-H ignition and 1/2" venturi carbs. They turn an 18-8 Classic in the mid 7's. Ive never put them on a plane.

any easy mods that have decent gains and keep it easy to start? I was thinking removing the jug seal and going with ultra black or red RTV and getting a bigger carb. if there isn't anything all that easy I'll probably just go to gas/glow, it's nose heavy anyway... already has a 1/2" exhaust exit...

I went the expensive route (?) and bought conversion parts from Carr Precision in Oregon - about $65. A friend, with a lathe milled down the fins on the flywheel. The muffler came from Ken Lambert.

I have a Mac 32 on CH ignition, it's very old from "Center Mark".. or something like that... It's a good running engine, and seems to be pretty peppy.... I had it on a Hanger9 Taylorcraft, proped it with a MSC 18x8... It really hauled the T-craft around.... much better than the G26, and Homelite25 I had on the T-craft before the 32.... I'm putting it on a CMP 72inch Zero... that should be fun.

Jim Dines what prop are u using and what kind of rpm numbers are you getting.
Thanks.

Jim Dines: I like the way your engine came out. That sure is a good way to mount mag coil. The exhaust looks nice too!. Capt,n

All the conversion stuff on my 32's came from C-H in Wyoming. Everything fit right up. Even the timing was a no brainer. There was only one way for the hall effect sensor bracket to attach and the hub was keyed.

Like Jim Dines's 32, they look like they were made to be model airplane engines.

Sorry my post was so incomplete. Mine is a 28cc. Initial runn was on APC 16X8. Here is more complete info:

http: http://www.rcuniverse.com/forum/m_38...tm.htm#3855475