Mustang Fever

My Feedback: (2)

I've got the one four stroke, a 91, and its always been a great engine. Makes me wonder if the problems aren't limited to the two strokes.

davidbegg

Everyone says that most Chinese engines are just fine, run really well, and are tremendous value for the price. However there are a small number of engines that just won't run properly.

I have found that it is possible to get bearings for the SC46 in NZ so if the price is OK I will get a set and see if that cures the problem. (air leaking in via the front bearing) Other wise I will have a paper weight with new bearings!!!

I would like to beat the thing, the problems have now reached the annoying and frustrating phase.

Cheers

David

jeffie8696

And think of how satisfying it will be to conquer the ill running engine and make it bow to your wishes!! (Sorry, I'm an engine guy [sm=lol.gif] )

davidbegg

I enjoy playing with engines too(all sizes), and are pretty good, but this one has me stumped. You think you have got it licked, back comes the same problem.

Trouble is that now I am not prepared to spend any real money on the engine.

Cheers

David

NM2K

My Feedback: (14)

Big Ed said it very succinctly when he said, "The true test of engine quality isn't how well it runs through its first gallon of fuel, it's how well it runs through its twentieth".

I couldn't have said it better if I had a million years to think about it first.


Ed Cregger

davidbegg

Absolutely!!!!

It needs to go down into everyones memory, for little R/C engines and also big engines.

Cheers

David

pitviper51

hi, just reading the thread after getting a new mag 91 4stroke yesterday in a trade deal, its going on a KMP husky. i dont have anything else for it so far and was wondering if theres an invert pitts that will worth on this engine. and what size fuel lines and plugs to use.. mine doesnt have a manual either..
mike

NM2K

My Feedback: (14)

I've been flying Sanye produced engines since they first hit the US over fifteen years ago. The first ones were sold as ASP engines. All of mine were fine, no problems. I owned a couple of .12s, a .46, a .61 ABC and a 1.08 ABC. All took a bit of a break-in and all turned out to be very usable engines.

I now own a plethora (always wanted to use that word) of Sanye engines, both ASP and Magnum. Again, no problems with them at all. Can this lucky streak continue? Yes, if you use a fuel with castor oil in it. The more, the better.

I'm not saying that people don't get a lemon now and then. Obviously, they do, but this is not unique to Sanye produced engines. I haven't found the problem rate with these engines to be significantly greater than any other engine brand. Your experience may be different from mine and I'm not saying that anyone is incompetent or lying about their experience. I just don't feel it is good to label a brand as being bad when it is unwarranted.


Ed Cregger

davidbegg

I didn't say that Sanye engine are rubbish, just that my engine will not run properly for some reason. I have seem a lot of Chinese engines that run fine. However I do believe the guy at the hobbie shop, most Chinese (Sanye) engines are fine, a few can be difficult to tune but will run fine, but a few just won't run properly. My engines istarts easily, idle is excellent, full power is fine, the transition to mid speed and down to idle is the problem, it will almost certainly stop with another dead stick landing.

My Sanye engine (SC) has been run in correctly and always run on fuel containing castor oil.

NM2K

My Feedback: (14)

As Big Ed said a few posts ago, the test of a good engine isn't how well it runs on the first gallon, but instead how well it runs on its twentieth gallon.

Many of us have been spoiled by OS and their near instant break-in. In fact, if all one has ever owned/ra/flown are OS engines, chances are great that the first venture into breaking-in new less expensive engines could be viewed as a tribulation.

One shouldn't expect any other brand of engine to run as well, out of the box, as an OS. That is what you pay the extra money for and not much else.


Ed Cregger

pitviper51

since i dont have the manual for mine, can some one scan a copy of the break-in and needle settign for the 91 in here, thanks
mike

Mustang Fever

My Feedback: (2)

Mike:

All the manuals on Magnums are at hobbypeople.net The are the US distributor, I think.

Here's the url on the 91RFS book:

http://media.hobbypeople.net/manual/210970.pdf

pitviper51

now im getting some where! i got some OS f plugs onthe way and 14x6 and 14x8 props, the plane isnt near done but i wanna get this thing bench running soon,, let it idle a gallon haha thanks
mike

Mustang Fever

My Feedback: (2)

Mike:

From experience, I would highly recommend getting one of the Thunderbolt HOT 4 stroke plugs that hobbypeople carries. The whole Magnum line seems to like hot plugs, and the Thunderbolt is very high quality. The original one is still in my 91RFS and is going on three years old, and has survived two airplanes.

pitviper51

ill give what i got coming a try, i may be running a fulltime onboard glow anyway, tho theres not alot of room in this husky..[:@] hard to work inside,, not like my 50cc yak that im used to..
mike

crystaleagle

My Feedback: (8)

Hey, guys, I have a 1.20 Magnum 4 stroke and am having a little problem keeping it running at lower rpm ranges, no matter if at lower or low middle ranges. It will run for awhile then just dies, like it is starving for fuel or just flaming out. The engine has been sitting for at least 4 - 5 years and we have completely cleaned out the carb and intake manifold. I was just wondering if any of you have any suggestions as to what is causing this and why, and how we can resolve he issue. We set the carb back to factory settings and tried and seem to be a little better, but still dies at low idle.
We also have a 1.80 4 stroke, Magnum, that is doing the exact same thing. It ran great until just recently, when we tried to adjust it. Please give me a list of things to check and possibly do to resolve this. Thanks, Crystal

N1EDM

My Feedback: (2)

You said that you cleaned out the carb, but did you also run a piece of wire through the fuel inlet (where the fuel gets metered into the carb throat)? Where the engine was sitting for 4-5 years, I wonder if that tube could be gummed up a bit, though I'm sure that you ran some fuel through it. Perhaps it is partially restricted with some old, hardened caster oil? Could you take out the HS and LS needles and run a fine wire through that tube to make sure that it's fully clear?

Just a thought

Bob

panzerd18

Hi guys, I'm wondering if you can help me. I want a nice alloy spinner for my 91 Magnum 4 stroke. I was wonder what sized adapter kit will I need to fit a 2-3/4" alloy spinner?

I am also confused with were the fuel tubing goes. Does the crankcase nipple need to be connected to the nipple at the top (not carb or exhaust nipple)?

mike109

G'day all. I knew I had owned a few ASP/Magnums so I did a bit of a count. My first was an ASP 46 Mk 1 about 1992. It looked rough, the general presentation was not all that good but it was a strong runner and did not give me any problems. At one stage I even had it running as a diesel but as a diesel it would not throttle very well with the very large carby. Next was an ASP 65 FS which I never ran. It too was a bit on the rough side but the subsequent owner ran it for over 10 years until it just died of over use. Next was a Magnum 30FS (in the white box) which went into a SIG Seniorita. It was perfect in the Seniorita but I eventually sold it to a friend and he now has it in a twin and it is still running well. Next was an ASP 52FS. I bought it to put in a Goldberg cub but it ended up in a very old SIG Kadet helping to train a friend. All was well until he pranged the poor old Kadet and it is at present awaiting some repairs. An ASP 61 FS ended up in the Cub. It is still there and running well. I have it set a bit on the rich side and it splutters a bit as a result but it pulls the Cub around effortlessly. It is also very light for an engine of its size and fitted in where the 52 had been (and an OS 40FS and an OS70 which was total overkill). My next was a second hand Magnum 46 XL purchased very cheaply from that certain auction site. I bought it to experiment with diesel conversions. It has had a lot of use but runs extremely well and is pulling a Great Planes Big Stick 40 around effortlessly. It is easy to tune, has excellent compression despite obviously high hours. I also have a Leo 46. I know this is not from China but from Taiwan. It too was an auction special and very cheap. I had heard of people having problems with these engines and bought it as a bit of a challenge. So far it has only a few flights under its belt but it runs ok but is not the easiest to tune. I suspect that the rubbish I cleaned out of the carby today may have something to do with it. Little bits of metal and plastic were inside the carby. My final Chinese engine is a Magnum 91 XL which I have just bought. I bought it because it was cheap and I don't know what I am going to do with it. It looks fine but I have not run it yet.

All my engines are run on 10% nitro fuel with at least some castor oil. I tune my engines slightly rich and as a result I get reliability and very few dead sticks. When I do, it is usually because I have not yet adjusted the low idle mixture or the plane simply runs out of fuel. I usually leave the low mixture alone until the engine has about an hour's running. I find that most are on the rich side from the factory.

I guess you could say that I have some experience with Chinese engines. They have all run OK for me. Some have been a bit on the rough side on the outside, some had rubbish inside them that needed to be cleaned out but they all ran well and were reliable. The big problem that I have seen in other people's engines has been the fit of the carby barrel in the carby body. A friend had two ASPs that were quite loose in this area and as a result, they ran erratically until he sealed them with grease. He eventually replaced the carbys. Another - a GMS 120 - starts well, has good power and idles well but once the plug is removed it dies. A permanent glow driver has fixed it to some extent after trials with plugs and fuels did not.

To me the Chinese engines represent good value but are best in the hands of more experienced modelers. Novices may find them more difficult to handle and would probably be better off with OS or Thunder Tiger engines. For ease of handling and just plain quality it is hard to go past OS but they are more expensive.

RC-Captain

I from time to time read the MAGNUM post and will not respond unless I feel not enough information is being given . So after reading this I have to say putting a continuous powered remote glow driver is not a necessary thing to do for any glow powered engine. If you flame out when the driver is removed something isn't set up properly IE low speed needle, tank height,wrong fuel, wrong prop size, twitcy low speed needle, etc. I found my magnum .28 ran better on 5% vs 15%. Magnum engines are challenge for the average RC pilot so I moved on to using other engines.


CAP

mike109

G'day RC Captain

I agree. The guy that owns that GMS engine is a relative novice. I have never seen the engine. I just hear the stories second hand. He is happy now but he has not really found and fixed the problem. The glow driver is just a band-aid solution. It was his first engine and would not have been my choice for a complete novice but some sharp salesman fitted him up with it. At least he has it running but there are any number of engines that would have been a better choice for a complete novice.

Mustang Fever

My Feedback: (2)

Panzer:

The Magnum 91, having a 5/16-24 crank, can use the standard Dave Brown adapters for OS 5/16 inch cranks. You'll see recommendations to use the the one with the jam nut, but I found that it doesn't work. I've been using the standard two stroke kit with good results. These all use a nut that is threaded on one end for the crank, and on the other for a 10-32 socket head capscrew that holds the spinner on, and include a piloted flat washer for the prop.

The Dave Brown ones are:

Short: S524 (Tower LXB953, $5.69)
Long: X524 (Tower LXB939, $5.69)

lilhachet

My Feedback: (2)

Hi, I have a magnum 91 FS.I went to start it the other day and when I take the glow starter off, it dies?I have tried two new plugs with no help, it will stay running at half throttle,but below that it dies? I tried setting the LS neddle but that didn't help. Help!

Mustang Fever

My Feedback: (2)

What does it do when you try to run at full throttle?

lilhachet

My Feedback: (2)

I just ran it again after ajusting the high and low needles, it won't even start unless the throttle is at more the half throttle, I have a new plug in it, 15% fuel,new, a 14/8 prop.and it won't run at less then 1/2 throttle, runs great at full???? This motor is broken in, by the spec's. and maybe 1 hour flight time. It ran great before. Also, what are the spec's for the valves?