grumman-cats

I have access to machineing equipment and was curious to what mods people have successfully made to lighten the engine as in case changes, fins mods, egnition options etc...
I would really like to remove as much weight as possible without causing any overheating issues and strenght issues.

arobatx

PM RCIGN1 on here. He converts them as pictured below. Machines new prop hubs, converts to EI, mounts ignition inside light machined mount, cuts off excess crankshaft in rear, and some have even rounded off the cylinder fins. Ralph is a great resource for this, good luck with your project!

mmattockx

You don't say if you have EI or a magneto ignition? By far the largest weight reduction is had by going to electronic ignition from the mag. I have an RCIGN ultra-lite conversion and it weighed a bit under 4lb with Ralph's standard cup mount and no exhaust. I have not weighed it since the cup mount was removed, but it should be several ounces lighter in the new configuration. Ralph's work is beautiful and his prices are extremely reasonable for it.


Mark

arobatx

I've got two of RCIGN's G62s. One with the cup mount (EI inside it) and the other one with flat plate aluminum mount, separate ignition, machined case and it weighs 3lbs 15oz with the ignition and muffler. If i can knock just one ounce off by rounding off the fins, I will be at 4 lbs even with the ignition battery Mmattockx is right, the biggest weight loss is converting to EI. trimming the case and cutting off the excess crankshaft are next. rounding the fins won't save enough to be really worthwhile weight wise, but it looks cool

arobatx

Just out of curiosity Grumman-cats, what are you thinking of installing this modified engine on? Are you just wanting to play with getting a nice, light engine, or is there another reason you are trying to shed the weight? Because none of these modifications will make the engine perform better, it will just be lighter, so power to weight ratio will be better, thing is, some airframes need the weight, some don't One thing the EI will do is make starting the engine much more pleasant

grumman-cats

I'm looking at the 28% wild hare egde 540. I already have the engine but I still have to get a mount and prop hub for it and yes it is still the stock ignition set up. The reason I ask on the fins is that when you look at other engines that are produced for aircraft specific installations they seem to have maybe one cooling fin for every two that the zenoah does. I know this engine was originally developed for other installations that didn't have the cooling that an aircraft would have. Thats why I asked on that one. I know the EI system will save alot of weight but other cosmetics may as well.

mmattockx

Consider that the density of aluminum is around 1.56 oz/in^3. To lose 3 ounces, you need to remove 2 cubic inches of material. That is a LOT of cooling fins. I had Ralph turn off some of my fins and it looks great, but I would be surprised if it saved an ounce. If you have the mag ignition, you lose something like 9-10oz going to EI. Nothing else you do will come close....

Mark

Antique

My Feedback: (4)

You could save a little more if you cut the crank flush with the rear bearing and drill out the rear shaft, maybe with a 1/4" drill....Use sealed 6202 NSK bearings, leave the seals out of thecase, cut the case flush with the rear bearing and mill out the rear case leaving only the mounting bolt holes.Or mill it all out and use long 5mm case bolts into a flat plate...Get some lightweight case and cylinder bolts from 3W...use a CM6 spark plug...Cut off the coil mounts and use a RC EXL separate ignition....A WT76 carb works just as well and migh be a little lighter than the HDA48D...Cut the threads off the end of the crank, tap it 5/16 and make a hub flush with the end of the crank, use a 5/16 bolt to hold the prop on...3lbs 10 oz maybe ?
Use a glow plug with no iginiton.Trim the fins WAY down, it works on the DA150 twin race modified engines..Glow fuel is good for about 600 more rpm, depends on the nitro, a G62 can take it.....

arobatx

...like I said, get Ralph (rcign1) on the phone, you'll have all of your answers

Chad

Tired Old Man

My Feedback: (1)

Not much to be gained by shaving the cooling fins other than a racier look.