Murdoc

I"m about to order a modeltech magic 40 size fun fly. What about install a gms 47 in it?
Anyone with experience on gms engines?
They seems a bit heavy though.. but I dont know

w8ye

My Feedback: (16)

The GMS 47 will take it for a whirl

opjose

Yup no problem with that...

Are you ordering a NEW GMS engine or do you already have it?

Just curious.

Sourkraut

Great little engine that will haul the Magic around just fine. I am running a GMS.47 in my Phoenix Funstar and it works fantastic. I also am running a GMS.61 in an F22 Raptor and the GMS.76 in a Hogbipe. All the engines work great and have awesome power. I do find that when they are cold they take a little longer to get running but once warmed up they are great.

opjose

Exactly!

I've often explained to owners of these and the identical Tower Hobbies engines, that they need to leave the glow ignitor on for 30 seconds after starting the engine for the first time in the day.

Then run it up a bit to get the head warm.

Once done the engine does very well there after.

Murdoc

I"m ordering a new one
This will be my first order from tower, I really didnt know that they have so good prices and so many products!
I have 8 hitec hs 422 servos, so I"ll just throw them in the magic

crazy8s

My Feedback: (21)

Murdoc,
The GMS .47 is a very powerful engine for its displacement. My son has one on his Hanger 9 .46 size Harrier and with a 12X4 APC prop it will pull it vertical till out of site. Hovering with it is no problem at all. He also has an OS .46 AX and an OS .46 FX and the GMS will out pull both of those engines easily on the same size props. Just be aware that the engine does require a proper break in period and it can be cranky till broken in fully. It isn't as user friendly right out of the box the way OS engines can be but once broken in it will out run and out last the OS engines in its size class.

Sourkraut

Murdoc,
The GMS .47 is a very powerful engine for its displacement. My son has one on his Hanger 9 .46 size Harrier and with a 12X4 APC prop it will pull it vertical till out of site. Hovering with it is no problem at all. He also has an OS .46 AX and an OS .46 FX and the GMS will out pull both of those engines easily on the same size props. Just be aware that the engine does require a proper break in period and it can be cranky till broken in fully. It isn't as user friendly right out of the box the way OS engines can be but once broken in it will out run and out last the OS engines in its size class.
[/quote]

AMEN to that brother!!

Murdoc

Sounds good I cant wait
But is gms the sort of engines that is impossible to start without an electric starter?

w8ye

My Feedback: (16)

I only use the electric starter

Sourkraut

Same here!

Murdoc

you guys are lazy! Am I the only one that prefers to hand start an engine?
Of course, if I don"t get it started by hand of some reason then I use my electric starter.

Wayne Miller

Hi,

There is another thread a while back on RCU dedicated to solving GMS .47 engines that were difficult to get running. In the end, after many suspected fixes, the problem engins seemed to be isolated to the line up of the hole in the fuel intake to the fuel intake nipple.

The thread is here:
http://www.rcuniverse.com/forum/m_22...tm.htm#2290854

If you have any problems with your engine, you may want to read through the thread, the final fix is there with pictures.

Hope this helps.

Fly4Fun,

Wayne

Murdoc

Thanks alot I"m sure that thread will be useful to me Again thanks!

opjose

If it doesn't show "IN STOCK" good luck!!!

I've have had 2 on order since August of last year!!!

I purchase the last 5 engines K&B had as part of their closeout promotion, along with a ton of very cheaply sold parts.

opjose

Almost ALL ABC engines are very hard to start by hand AT FIRST.

This is because the engine is not worn in yet and the sleeve and cylinder have an extremely tight fit out of the box.

So tight that you may believe you will break something...

The key is this...

DO NOT cowl or cover the engine until you've run a few tanks through.

On your very first start up attempt, use a heat gun or hair dryer to heat up the cylinder head.

Get it to the point that it is almost HOT but be careful with your plane's covering if you have the engine mounted.

Then immediately prime and start the engine before the cylinder head cools off.

Once you do have it running, run it a BIT rich, not slobberingly rich, for a full tank, taking the engine up and down from about 70% open throttle down to idle and back many times.

After this follow normal break-in proceedures with additional tanks of fuel.

After you've run about a gallon or a gallon and a half through it, you'll find that it will settle in.

Until then run the high end a bit rich and leave the idle a bit high... also if possible use a heavier prop, like an APC.

The slight extra mass helps keep the engine going, especially at first... a flywheel or spinner weight will also do the same thing.

Afterwards you'll find it EASY to hand start, once it has been broken in... usually requiring only a flip or two after priming.

Whirley Bird

My Feedback: (1)

AMEN to that brother!!

[/quote]
I received my 61 Evolution today.
I set in a stand and put that in a vice.
No problem starting.
I used a 14x5 prop to load it down a bit and I used a full quart of fuel to run it in.
It's idling nice and smooth and my TAC was showing close to 18,000 RPM
Now i'm waiting for the Tower hobby 60 MK III with an OS 65LA engine.
I want to compare the two different engines.
That trainer has semi symmetrical type of wing so it should fly nice.
I have already ordered that and the [parts needed to converted to a tail dragger.
Vegas/

w8ye

My Feedback: (16)

The GMS 47 is shown as in stock

opjose

Great! Maybe some actually and finally arrived... mine still show "late december"... a backorder of well over a year and a few months!

crazy8s

My Feedback: (21)

I received my 61 Evolution today.
I set in a stand and put that in a vice.
No problem starting.
I used a 14x5 prop to load it down a bit and I used a full quart of fuel to run it in.
It's idling nice and smooth and my TAC was showing close to 18,000 RPM
Now i'm waiting for the Tower hobby 60 MK III with an OS 65LA engine.
I want to compare the two different engines.
That trainer has semi symmetrical type of wing so it should fly nice.
I have already ordered that and the [parts needed to converted to a tail dragger.
Vegas/
[/quote]
Whirley Bird,
I'm not sure what the relevence of your post has to do with the subject of this thread which is the GMS .47 but I am curious as to why you are running an Evolution .61 at such high rpm's during break in. 18000 rpm's?? A quart of fuel isn't very much for a break in period and those numbers seem extreme for a .61 size engine. Btw, there are lots of Evolution engines at my flying field and while they are user friendly right out of the box they also seem to be the first ones experiencing bearing failures after a season of flying which is ridiculous. I think the manufacturer in their quest to make an inexpensive engine are using the cheapest bearings available. Powerwise the Evolution .61 is going to have it all over the OS .65 LA. It's the whole ABC type engine versus a bushed bearing engine thing.

nebp40man

Hi, Just signed up for rc universe just so I could respond. I own Four .47's and a couple of the bigger engines. I have used the .47's extensively over the years. They run really well once they're broke in. The guy I fly with is a diehard OS. buyer. The .47's I've had fly circles around the comperable OS. (comperable planes, weight and size)[8D] The only drawback I can say about them is, You can't seem to ever shut them down, even with radio trim all the way down. They will sputter a bit and finally stop. I don't know if the carb barrel is not a tight enough fit or what. Run them a little rich on your flights. I think all 2 strokes tend to lean out on hot days and this can make landings interesting if your engine is not running. Hope this helps, good luck.

w8ye

My Feedback: (16)

nebp40man,

Welcome to RCUniverse as a poster. Hope you have many years of enjoyment.

Jim

Wayne Miller

Hi nebp40man,

Welcome to the thread, hope you are finding it interesting.

I think the only thing that will cause an engine to continue to run with the carb fully closed is an air leak, usually around the base of the carb, there is a post here somewhere talking about sealing the carb mounts and barrel - you may want to take a look. Perhaps someone already knows where the post is, I'll take a look as well.

Fly4Fun,

Wayne

opjose

You really need to crank the carb down HARD when ( or before you start ) you tighten the retaining bolt.

Also those cardboard red washers they use tend to leak. Remove the nipples and fittings and apply blue locktite around the threads. This helps a lot.

I've had a couple of GMS engines that do this and I've been able to eliminate the problem by doing the above.

Don't forget to check the tightness of ALL of the cap screws. After the first few runs they WILL come loose.

Now if I could only fix the SuperTigre's identical problem so easily! It has a bad airleak around the throttle barrel. ST even put a rubber ring around this area to help but I find it ineffective.

w8ye

My Feedback: (16)

The Super Tiger, GMS, and Tower engines are all made by the same (GMS) company and share some of the same problems