Heli-NuBee

Hey j301, thanks for the update. I'm glad to hear that your engine is performing well.

Heli-NuBee (AKA Roger the radial rabbit)

mchandrayan

I have been flying my NGH 35 for some time now. With all the initial teething troubles the engine is now settled and working well. I had the problem of fuel being sucked out from the carb, which was cured by installing an aftermarket venturi

Heli-NuBee

Thanks mchandrayan, I'm glad to hear you are having good luck with your engine.

Best wishes and good safe flying.

Heli-NuBee (AKA Roger the radial rabbit)

Heli-NuBee

Update, I replaced my NGH 38GF four-stroke engine in my CMP BF-109 with an NGH 35GX two-stroke engine due to excessive vibration. The new NGH 35 CC engine runs great but also has a lot of vibration. The engine vibrated the screws out of three of my servos on only three tanks of fuel for break-in. It appears to me that the NGH brand runs quite well but does seem to have an issue with balance and vibration.

Best wishes and good safe flying.

Heli-NuBee (AKA Roger the radial rabbit)

Heli-NuBee

I installed a Dave Platt spinner and did some more break-in runs with a bit of tuning and the engine is now running much smoother. My CMP BF-109 is now ready for its maiden flight.



Best wishes and good safe flying.

Heli-NuBee (AKA Roger the radial rabbit)

Heli-NuBee

I had my maiden flights on the 109 Wednesday morning. The plane flew very well and the engine ran great. The only issue encountered was the tendency for the landing gear to bounce if one trys to turn the plane while at any speed on landing. Even slight corrections on the ground result in severe bouncing. I got away with it the first flight but the second flight resulted in a nose over and broken prop. I am not sure how to cure this issue except to let the plane roll out until very slow on landing. I used the retracts sold by Nitro planes for the 109 and they work well but seem a bit on the weak side for this plane. Here are some pictures of the maiden flights.



Best wishes and good safe flying.

Heli-NuBee (AKA Roger the radial rabbit)

Heli-NuBee

I did a test run on the NGH-38GF engine powered GP Super Sportster today. I got the engine running much better. The low needle was quite rich and tuning helped the low end shaking. However, the engine bolts came loose in less than five minutes of running from vibration. This engine runs strong, it is a shame that it has so much vibration. I rechecked the prop and spinner balance but they were good. I had blue locktight on the engine bolts, maybe I need to go to red locktight. I will keep tying, I think it will be worth it in the end.



Best wishes and good safe flying.

Heli-NuBee (AKA Roger the radial rabbit)

Oooops! My Bad! I ment to post this on the NGH 38GF forum. Sorry!

SIX GUNS

wow this seems to be the same old story these NGH,JBA and all the other Chinese engines of this design have a carberation issues the one thing I have
found is to use a small bore weed wacker carb and that does cure some of the issues but the carb that comes with the engine is designed for a much bigger engine and untill the problems get resolved with the timing and a better carb the NGH , JBA and other small engines are going to be a problem so buyer beware the reed style engines have been doing fairly well from the info that I have been seeing the engine that has been doing well is the elevation engines which has a complete different carb design all together

Launch Pad McQuack

Can someone give me the measurement from the bottom of the mounting lug to the top of the spark plug socket cap? I have the measurement to the top of the plug...wondering how much the cap adds. Thinking about this on a 80" Platt FW-190 and would like to keep it in the cowl.

RBean

Don't have the measurements now but will be home in a couple of days and measure. I purchased mine from Agate Racing. Started ok, idle good with good response and top end. It turned a Zoar 17-8 three blade prop 7,320 rpm when new and now after five or six flights, 7,600. I have it in an CMP 109, 73" wingspan, 15.5 lbs. It is plenty of power. However, I had a throttle servo malfunction and made a bad landing breaking the prop and bending one landing gear strut. I think the servo was too close to the muffler and the muffler was loose. I'll try a different high temperature thread locker and move the servo.

Launch Pad McQuack

Thanks the Platt requires a Beam mount. I want to remove the ST 3000 that is in it and go to a gas engine. I am thinking this may be the ticket. But with an up right engine I don't want to have that cap hanging right out on top.

captinjohn

Redo the thing with the cylinder head down or any downward angle that will work....Done !

RBean

Pad Launch,

From the bottom of the mounting lug to top of spark plug cap is 5.25". You may want to reconsider the NGH 35. I bought mine new form Agape Racing. It has run good with no problems and I have 10 flights and two short ground runs on the engine. On the last flight the throttle started acting erratic which help cause a bad landing and damage to plane. Broke the prop and bent on gear strut. It turns out that the throttle servo was malfunctioning due to excessive heat. The reason it showed up on flight no. 10 and not before is because the muffler broke right at the mounting flange and hot exhaust gas was escaping into the rear cowl where the servo was located. Here are pictures of the broken muffler. The prop and spinner were balanced and there was no unusual vibration. I read this thread and understand that this engine had muffler problems, but I thought they had been solved. I guess not. I'll contact Agape and see what they will do. Also there is a local guy who can weld small aluminum. Maybe he can repair and reinforce with a bead around the fracture.

captinjohn

It sounds like this engine needs to be better balanced..............

mchandrayan

R Bean
Was your muffler mounted with the engine in rear exhaust configuration?
I have had great throubles with this muffler. Initially the muffler kept coming loose from the exhaust manifold, this was fixed by no longer using the supplied (and spare) gasket and using high temp RTV instead. Then the 6 bolts keeping the two halves of muffler together kept falling off. This was solved by using nord lock washer on all bolts. And finally the muffler broke exactly like your picture. I even sent some money down the drain getting a spare one. The issue was finally fixed by getting an after market muffler. I and a friend both use the after market muffler and that has never come loose (but the engine is now in side exhaust configuration)

P.S.
I see from previous posts that your engine was indeed rear exhaust configuration.

SIX GUNS

mchandrayan , can you post pics of the new muffler you installed ??

mchandrayan

That would be a bit improbable at this time as I would need to take off the cowl and then take a picture. But next time I need to take the cowl off, I would take a picture and post it here. I have the engine back to side exhaust and mounted inverted with this muffler.
I bought the muffler from Agape Racing, currently shows out of stock. I also did not use the gasket and used the red RTV
Here is the link
Hope this helps

RBean

I got he broken muffler repaired. It was welded and reinforced in the break area. Got one flight and the muffler came loose again (but didn't break). Removed, cleaned bolt thread with Natpha and used permatex high temperature thread locker. Had one ground run and one flight and so far, ok.

RBean

On the second flight after reinstallation, the throttle servo started acting up again. I was able to land ok. The muffler broke again just out side of where it was welded. I got the after market muffler from Agate Racing, meant for a side mount, but used on the rear mount. Have not run yet, I hope it fixes the problem.

mchandrayan

I think there is a bit of mechanics involved there. What I feel is that major vibration and the movement of the engine is in vertical plane that translates to the engine head and upper case moving in vertical plane and also in the longitudinal plane. When the muffler is mounted in rear configuration the mass of muffler wants to resist the movement While the head and case still want to move. Now that is going to stress the manifolds especially given the angular transitions are more likely to fail. A lighter muffler would last longer. The issue of adequate cooling for a rear muffler will also present an issue. My prediction is that the Agape muffler will also come loose in rear configuration or may even fail. While it would last much longer in the side configuration

SIX GUNS

I would have to agree with that also making sure that the prop and spinner are balanced and if this continues I would take the engine apart and check the balance of the engine its self witch is very simple

RBean

The prop and spinner are balanced. When running, the engine does not seem to have any more vibration than other single cylinder gas engines that I have. I also reinforced the engine mounts somewhat. Here are pictures of the new muffler.

mchandrayan

The agape muffler being much lighter than the stock item should last much longer in the rear exhaust configuration, since the mass resisting the movement is going to be much lesser. In your installation I assume you have to dismount the entire engine in case you need to take off the muffler. That would be a fiddly work

spaceworm

Sounds like excessive vibration and a marginal muffler design/material. Is it possible to provide additional support for the muffler with straps or brackets. Several engine/muffler manufacturers provide/require this additional support for the muffler. I am wondering if soft engine mounts or hard mounts is better. any one using soft mounts?

Sincerely, Richard

mchandrayan

Yes I would say that the stock muffler is not very suited for rear exhaust option. I have the engine mounted on nylon bearers and ever since I went back to side exhaust with Agape muffler all my problems vanished