Flyer Freq

I can't believe I am letting myself get sucked into the GMS running problems debate again, and I know this isn't the point of this thread. I have no idea if GMS is going under or not, but I seriously doubt it! I have been wrong before.

We have a few of the GMS engines at our field. Awesome engines! Really! We did get one of the problematic engines, though. Its owner let me play with it, and I worked with others in a thread here on RCU, to solve the problem. The solution of drilling the intake nipple should have never, never , never, never been suggested!!! Many don't realize that the the size of the ID of the intake nipple and the size of the nipple ID on a muffler is often a calculated size for proper running/breathing. If you change any of these dimensions, you are changing how the engine breathes. Some have gotten away with it, but they were only putting a band aid on the real problem.

There were two problems, common to these engines. The problem with the engine continuing to run, even when the barrel was closed was usually due to the O-Ring not being properly seated. When you installed the carb, the carb needed to be twisted into position and held tightly in place while the jam nut was tightened. As far as the problem with the engine not transitioning under load, there was a period of time when the hole in the spray bar was manufactured in the wrong spot. Flow was partially blocked by an undercut area in the carb. The fuel had to enter the inlet, take an imediate right hand turn, go under a ledge the was blocking part of the spray bar hole, and then the fuel would go down into the spray bar, where it had to take another abrupt turn. There was incredible turbulance there. This turbulance created bubbles, as you transitioned the speed. The bubbles created a "lean" run. I took the spray bar out of a good engine, and replaced it in the one that wasn't running right. The engine imediately came to life and has never had another problem. I purchased a new carb body, which comes with the spray bar, and put it back in the good engine, and it runs great too. I have swapped the two carbs back and forth, and no problems! I preached this until I was blue in the face, on the "GMS Running Problems" forums, and it fell, mostly on deaf ears. People seem to prefer complicated fixes where they have to drill holes in something, rather than a simple $8.00 fix. I know my fix was right for many people, as I received e-mails and PM's from people that took my route and it fixed their engines. I know there could be other issues, but properly seating the O-Ring and replacing the Carb body will probably take care of 90% or better of the problems. My GMS .47 is so discollored from hundreds and hundreds of trouble free flights, it is unbelievable, but it just keeps going! It will out turn the OS .46 FX or AX at every turn.

I hope this will help some of you get your engines going. I hope that GMS is not gone, as it is a great engine!

Andy

Iflyglow

My Feedback: (79)

It is kinda funny that GMS, Super Tiger,Magnum and Tower engines are all made by the same factory, but only the engines marketed by GP are having supply problems. Magnum does not seem to have a supply problem. I am willing to bet that OS is putting extreme pressure on Tower (GP) to limit the sales of the engines which are cutting OS'S throat. Lets see, a Tower .75 for $94.00, or a OS .75AX for $180.00. I do not have to even answere this one if you have ever seen a Tower .75 run.

w8ye

My Feedback: (16)

Just for the record the Magnums are made by Sanye near Hong Kong and are also sold under other names such as ASP, SC, SY, Evolution, Kyosho, etc.

The Super Tiger, Tower and GMS engines are made by GMS. It took this company 2 years to get the Super Tigers going after they took the machinery out of Italy. I actually have no clue as to what is really wrong with them other than what has been mentioned in this forum. The way everything was out of stock at the same time makes you think that the factory burned down or something?

Thunder Tigers are made in Taiwan and some of the older Magnums and Tower 40 engines were made by Thunder Tiger back in the early 90's.

jeffie8696

After getting my GMS 47 pushed back for 3 months through Tower I just gave up. I have a wonderful GMS 32 and was looking foreword to the 47 but I ended up with a new in box nice running Magnum XL 46A. Purchased here from a fellow member at a considerable savings. I couldn't be happier. Sorry GMS and OS.

XTOL

Does anyone REALLY know whats going on? Ive been looking
to get a Tower 75 for my Sig King Kobra since NOVEMBER.

An email to Tower customer service netted no reply. A phone
call didnt get a whole lot more information. Just that they would
be in "late February". That of course didnt happen and they
are now saying late March.

After 4 months I have every reason to believe that date will
also come and go without seeing a motor for my plane.

Mike Hammer

w8ye

My Feedback: (16)

Back in the days when they were moving the Super Tigers from Italy to the GMS factory in China, we went through all this for over 2 years. It was always in about a month. When they did come they were made from Italian parts. It was another year before the full line was out and all the parts were made in China..

bigedmustafa

My Feedback: (2)

There isn't much you can do if you need parts, but if your only problem is you can't buy a GMS or Tower Hobbies engine right now then you simply need to check out all of the other viable options:

(Aviatronics) Aviastar (distributed by Sig Mfg)
JBA (distributed by Kangke USA)
SK (distributed by Kangke USA)
Magnum (distributed by Global Hobby)

I like Super Tigre and GMS engines, and would certainly buy more of them. There are other fish in the sea, as it were. With the Aviastar .53 and the JBA .56 available for $79.99 and the SK .50A and Aviastar .46 available for $59.99, there are plenty of good alternatives to the G-45 ABC or GMS .47 out there.

With the Magnum XLS .46A available everywhere for $69.99 and parts for it being plentiful and cheap, it kind of makes shopping around for a good, powerful, inexpensive 2-stroke seem like wasted effort.

Somebody needs to tach a JBA .75 ABC engine side by side with a Tower Hobbies .75 ABC engine so all of the folks biting their nails over the TH .75 being back-ordered can realize there's more than one choice of engine on the planet.

There's no shortage of good, cheap, powerful engines out there; there's only a shortage of them at Tower Hobbies.

jeffie8696

Yea you hit it on the head. I really love my GMS 32 and I thought the 47 would be the perfect stable mate but I am really happy with my Magnum 46. And I got it NIB here on the forum for a lot less than Tower. Sorry Tower.

XTOL

Just in case no one has noticed yet Tower is starting to push back
the dates on long out of stock Tower/GMS/Super Tiger engines to April.

Surprise surprise...

After waiting for a Tower 75 since last November its time to explore
other options. And that WILL NOT be OS.

Mike Hammer

jeffie8696

Mike, my Thunder Tiger GP 42 (actually it's a .396 according to the specs) after a minor port and polish solidly kicks my like new OS .46LAs butt! Same props same fuel same glow plugs ! And I am not even done with the "Mighty Tiger" yet. AND my Magnum XL .46 kicks said .46 LAs butt out of the box.

bigedmustafa

My Feedback: (2)

Do yourself a favor and try the JBA .75 ABC 2-stroke from Kangke USA, you won't be sorry.

XTOL

Ive been thinking about that but I dont know much about them.
I have seen some of the SK engines at our field and they have
been excellent. Only problem is they are ported for larger props
at lower RPM. Not exactly what I was looking for for a speedy plane.

Thats why I was wanting the Tower 75. Its pretty well regarded and known
as a screamer. And parts are easy to come by. But that doesnt mean squat
if you cant get one.

If you have a JBA 75 what kind of props does it like and what kinds
of RPMS are you seeing? This will be for a Sig King Kobra.

Mike Hammer

jeffie8696

So are the GMS engines pushed back to July yet?

blw

My Feedback: (3)

Please keep the thread centered on the original topic, and not about suggesting other engines.

NM2K

My Feedback: (14)

My apologies to friend Barry. That was intended to be a PM, not a public post.


Ed Cregger

russm

i guess this explatns why i have been waiting 5 months for my th76 replacment or repair. i will say that hobby services has been pretty square with me though.

Bax

My Feedback: (11)

According to the best information we have at this time, GMS engines are due to be coming back into stock in early May of this year.

NM2K

My Feedback: (14)

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I have nothing but good things to say about Tower Hobbies, their fine crew and policies. I've been with them through several owners, since 71 or so, and have always been treated fairly. I'm one of the lucky ones that has never had a screw up with Tower Hobbies. Of course, I know I'm not alone. It didn't come out right. <G>

I hope that Tower gets their .75 & .61 back in stock soon. I'm thinking of buying the .61 for SPA/BPA use. A rear exhaust version (at the same price/sans muffler and with an OS VF bolt pattern for the exhaust flange) would be nice.

If the JBA engines, and I say "if", cause I don't know, are as heavy and massive as my Lincoln .61, I might hesitate to buy one, since I'm flying some older pattern ships that were designed for the weight of a K&B .61 or Super Tigre G60 Bluehead (20 ozs. w/no muffler). Something in the 25 ozs. range might require tail weight. I should go look at the JBA engine specs. before dissing it because of its imagined weight.


Ed Cregger

rcdude7

My Feedback: (264)

Hello Bax,

Do the SuperTigre engines come through the same pipeline? I have been waiting for a .51 C/L engine to become available through tower. I would buy one on the second hand market to avoid the wait, but they just don't pop up very often.

blw

My Feedback: (3)

Ed,

No problem at all, and thanks. Everyone knows that you are always trying to be helpful around here.

borna

check out my GMS conversion from Glow to Gas. Lots of good pictures.
http://www.rcuniverse.com/forum/m_61...tm.htm#6165393

Borna

aviapilot

O.S. ducted fan engine cylinders are chrome plated (in Japan). [sm=49_49.gif] Therefore it is not a question of enviromental protection.[8D]

longdan

Guess they didn't make it?

jeffie8696

I guess the one I ordered in January is still on back order. Good thing I went to SIG and bought an Aviatronics Aviastar .46 instead. And I won't even look back!!

alcarafa

Bill its been 3 months since your " best information at the time" still nothing , did mecoa lets call it " GMS GIVE AWAY " offer say something to you guys ?

No more GMS' s sad but true, finally got it ?