I cam across a ASP 61 2 stroke that was about 4 or 5 years old. It was never been started. The HSN was turned out about 5 or 6 turns and the LSN was turned out 6 1/2 turns. On the LSN does turning it clockwise make it more lean. I did have it started and seems like screwing the HSN in and out didn't make any difference in the running. When I would throttle it up the engine would quit. That would I think indicate that the LSN is to lean. Looking for some suggestions. OK GrayBeard I know it is not a OS or YS.[][&o]

I would start out reading the engine manual.

don't got!!!!!![&o][&o][&o]

Then don't start turning screws on the LSN UNTIL you get a manual. They are factory set by most engine MFGR'S.

HUMMM!!!! to late. I had to take the LSN out in order to adjust the throttle arm. I screwed it in first before I took it out. It was 6 1/2 turns out. when I moved the throttle arm to the position I needed I put the LSN back in and the turned it out 6 1/2 turns. I can't believe that this would be the factory setting. I have lots of 2 stroke engines and none have the LSN out that many turns. What I wasn't sure if turning clockwise on that carb was leaning the LSN.

Take the carb off the engine and open the barrel all the way. Looking in the carb from the bottom you will see the spray bar on the HSN side and you will see the tip of the LSN on the other side. Set the LSN so there is a small gap between the two, do not worry about how many turns it ends up being. Set the HSN to 3 turns. Put the carb back on and try to start the engine. this should be close enough to get the engine running and up to full throttle. Adjust the HSN at full to peak RPM and back off 1/8 to 1/4 turn. Now bring it down to a fast idle, remove the glow igniter. If it sputters and stalls, you are very rich and need to screw the LSN in. Adjust 1/4 turn at a time. If it drops RPM but runs for a little bit you are a little rich. Adjust so the RPM drop when taking off the glow igniter is just noticable. This will get you very close.

Try this Magnum .61 manual since ASP and Magnum engines are pretty much the same anyway: http://media.globalhobby.com/manual/210770.PDF At the top of page #3 (at about halfway down the manual) it tells you how to reset the low speed needle to factory specs. I think this should get you in the ballpark to at least get it running again. Btw, "Speedracerntrixie" in post number 6 is spot on too.....so now you have two ways to try and get that booger running again!

By Golly, the Magnum manual shows the LSN out 5 turns. so maybe the 6 1/2 was in the ball park. I put another carb on this evening and I will see what happens with that one. I will keep everyone posted and thanks for the help.

BTW! No needles are set at the factory. "Factory settings" is a myth. You may get lucky, and the assembler screwed it in til it will run, but don't expect it to be right. Too many things affect the settings to expect an out of the box setting to be exact. A friend got one once that had the idle jet all the way shut. He was ready to throw the engine a way until I opened the idle jet for him. I read a mag. article once where the author set the idle by closing the throttle and blowing in the fuel line while slowly opening the idle. When he could hear air hissing, it was close enough to run and set.

Well I changed carbs and no difference. It is getting plenty of fuel. I removed the HSN, put my finger over the muffler and turned the engine over with an electric starter and plenty of fuel coming out of carb. Good plug, fresh battery on igniter, fresh fuel. Out of patience. Another paper weight that resembles a engine.

Yes quiting suddenly on throttle up is a sign of a rich LSN. If the high speed needle doen't change the mixture, then you likely have trash in the needle, or a leak in the fuel line.

Take it appart and see if some one didn't put the sleeve in wrong

Never had one apart. how do I know if the sleeve is in wrong. I can tune em, just don't know how to take them apart.
What do I look for when I take the head off.

There is joy in Muddville today., took the carb off of my 75 and it now runs great.[8D][8D] Now I have to figure out what was wrong with the original carb. [X(][&o][]

irish,

In your first post you said this was a new engine that had never been started. Are you going to a normal tune on it, or runnign through a proper break-in procedure with it running rich?

Hogflyer

Yes it is a new engine. When I had it running, just above idle it was very rich. I let it run about 4 minutes then was going to throttle up. It quit, I could not get it started again. I flushed the carb out, made sure it was getting fuel, checked the glow plug, checked the igniter still nothing. Put the carb on from my 75 and it fired right up. Still running it very rich. I do have it mounted on a plane, but I also have a flight stand at my home like the ones at the field,. Don't know what to look for on the original carb. I can take a picture of the carb if you think that will help.

There isn't much to those carbs. The stop screw and one nut should let the barrel out. The only adjustments on assembly are the needles. Look for something around the needle. Maybe it isn't going in as far as it should and can't lean out.

I'm going to fly the plane before I put the other carb on. Haven't flown this one for some time. It is still one of my favorites. Scratch built Not-For-Sale.

Hi!
Did you adjust both needles on you first carb?

Yes I did. After it would not run

That will be your next thread Taking an engine appart, reassemble and get runing. with pic's
Larry K

If you have many 2 strokes, you should be familiar with them. Bottom line is the LSN is set way to rich when you advance the throttle. Do yourself a favor, read up on this engine and see how it works. Then ask questions later. E.O.S.
CW Leans, CCW, Richens.

goirish,
Many Chinese engines have trouble running good even when brand new.....this fellow named Wayne Miller had 2 GMS .47 2 stroke engines....one was running good and the other would quit on Wide Open Throttle.....well after putting a baffle inside the muffler he got it to run good.........However, he was not satisfied as the engine should run good without the extra muffler restriction brought about by the baffle inside the muffler..............So he took away the baffle and then.........he decided to take a look inside the carburetor fuel inlet nipple........inside he could see the brass insert with the fuel hole that should be lined up with the fuel inlet nipple........Lo and behold!!!!!! the fuel hole of the brass insert is misaligned with the hole in the fuel inlet nipple. So the fuel at Wide Open Throttle was restricted from going straight into the spray bar inlet hole and was cutting off the engine at Wide Open Throttle. So he removed the fuel inlet nipple and drilled it one drill bit size larger and also drilled the inlet hole of the brass tube so that both fuel holes line up. I copied the drawing that Wayne Miller made so that the problem and the solution could be better understood. Larry.

I copied Wayne Miller's solution in here along with his drawing I posted previously at the above post and I attached also the picture taken by FlyboyDave of the misaligned fuel holes with the fuel inlet nipple removed for better clarity. So here it is "The problem seems to be fuel turbulence when fuel leaves the fuel intake nipple and takes a sharp turn when it enters the needle valve area (see drawing attached). This can create foaming, and in worst cases, a fuel air lock. This makes carburetor adjustment difficult and may even cause the engine to quit while in flight. To give credit where credit is due, this problem was identified by another modeler, Andy, in an earlier post and you should read it.

We have tried many things to fix this, such as, more muffler pressure, enlarging fuel/exhaust nipples and drilling the carburetor brass insert. Drilling the hole larger in the brass insert seems to have done the trick, I have just drilled three GMS .47 engines and all work well after the modification. Drilling the nipples does not seem to affect the performance, but doesn't hurt either.

I'm going to try and upload a picture to help those who have not done the modification yet. The modification can be done with the brass insert in place (although you have to be very careful not to damage the nipple threads) or by taking out the brass insert and drilling (preferred).(....to prevent drill shavings from going inside the engine.....take out the carburetor and drill it outside the engine and spray clean with brake cleaner the fuel passageways... DO NOT use carburetor cleaner!!!!....carburetor cleaner is very aggressive and will ruin the carburetor O rings).

The hole in the brass insert should be as close as possible to the "shoulder" of the brass insert and directly under the fuel intake nipple.

If you chose to try this modification, please make sure you do not have a carburetor air leak (where carburetor enters engine body) or an air leak at the engine back plate. If you do, you must seal first. Seal with Ultra Copper Hi-Temp RTV by Permatex (available from auto motive stores) or replace "O" rings as necessary. Testing for air leaks is described earlier in this thread.

Please be aware that any modification will void your warranty.

See instructions below and refer to the attached picture for part location. I've included two sets of instructions, one for drilling with brass insert in place and the second to remove brass insert for drilling.

If you chose to drill the brass insert in the carburetor:
1. First remove the needle valve retaining nut, needle valve and the intake fuel nipple to avoid damage to the needle valve. Drill the fuel intake nipple one (or two) size larger.
2. Reinsert the fuel intake nipple and then use it as a drill guide, this will protect the nipple threads.
3. Very carefully drill through the fuel intake nipple and into the brass insert.
3. Remove all brass filings from inside the brass insert and re assemble the carburetor.

If you wish to remove the brass insert to drill (preferred method):
1. Remove the intake fuel nipple
2. Remove the needle valve assembly by taking off the needle valve retaining nut retaining nut to avoid damage to the needle valve.
3. Remove the retaining screw
4. Remove throttle barrel, be careful, there is a spring behind it. Note: small end of spring goes into carburetor first.
5. Using a hardwood dowel or brass punch, carefully tap the threaded end of the brass insert until the brass insert comes out. Note: be careful not to damage the threads.
6. Drill the hole into the brass insert at a slight angle towards the carburetor throat (same angle as fuel intake nipple).
7. Clean out all brass filing out of brass insert and remove any drill burrs.
8. VERY IMPORTANT! Reinstall brass insert so the enlarged drill hole is directly underneath fuel intake nipple. To reinstall brass insert, you will need a hollow punch and a backup block with a hole (preferably made out of a hardwood block). Set the brass insert in place so the newly drilled hole will line up under the carburetor nipple. Put the carburetor over the hole in the wooden back up block and gently tap the brass insert in place using the hollow punch.
9. Reassemble carburetor.
After the above, you should adjust your engine as described in earlier posts.
I have just done this with three engines and they all work well."

P.S. When clicked the illustrations will enlarge and then you can see very clearly the misalignment of the 2 fuel inlet holes and what solution Wayne has done by drilling and enlarging the fuel inlet nipple and the brass insert holes to line up properly. This was on an RCU thread started by Wayne Miller here on the glow forum. Before Wayne's modification, the GMS .47's were so starved of fuel that the High Speed needle could be backed out so much that it is nearly falling off and the WOT mixture still will NOT richen up....resulting in a dead engine. The name of the thread is "RE: GMS engine tuning problem". There were many other helpful tips on that thread such as making sure that the low speed needle is completely clear of the spray bar tip .002"-.003"away from the spray bar tip at WOT so that there is no restriction on the spray bar tip at WOT. God Bless y'all. Larry.

It does the hobby community proud when a person like yourself knows' what he is talking about.