Charley

My Feedback: (2)

I sent NV the exact same message that I posted here. Did you give him as much detail as I did?

CR

Billsky

My Feedback: (37)

Two GX-40's left for sale, get them while you can. I'm done with all the irritation. The O.S. GGT 10's are running great with very little fuss. Running better after each tank.
Sometimes when you pay more you get the results expected.

Charley

My Feedback: (2)

This morning I put an second head shim in my GX-40, along with a new graphite head gasket & test ran it to see if it helped. The engine ran longer than before but still stopped running after a few minutes. So I put another head shim in, for a total of three shims. The engine ran through about 2/3rds of an 8 oz tank at half throttle before quitting. The HSN was less sensitive to adjustment than before but it still sounds to me like it's detonating. Makes me wonder if the gas I bought from my local "Stripes" store is up to its 92 octane rating. I wonder if any of these octane boosters work. Maybe some Avgas?

I was going to try a 10x7 prop but I managed to get my right hand into the APC 11x6 prop. The prop tips sliced through the nail on my index finger & gave me a 5-stitch slash on the back of my third finger right over the knuckle. Can't bend that finger now. It will be a week before I can get the stitches out. No more testing until then.

CR

Charley

My Feedback: (2)

I bought the GX-40 for the pure helluvvit. No regrets We could always replace the gas head buttons & needles with the nitro parts. Or are you wedded to gas?

CR

DaOldGuy

I gave him enough details he didn't seem to want to question anything. Sorry about the finger Charley, that sux when the NV is taking blood money.

Adding Shims would reduce compression and thus remove the need for high octane and loose some of the advertised HP. Bill and I are some what "wedded" to gas basically since the cost drops and the Flight time and HP get really good. Since the owners manual is off on so many things it just seems possible the break in prop could be wrong too and I was considering dropping to a 10X6 as well.

Bill is spot on about paying more for the GGT-10, they have a real gas carb and you can actually fly them. 8)

Charley

My Feedback: (2)

Since my engine still seems to be detonating the CR may still be too high for the fuel I'm using. I may have an engine wherein all the production tolerances acted to raise the CR to the max. I'll play with it some more next week. As for the OS gasser, I'll wait until TT, et al, makes a clone for a more reasonable price. Meanwhile I have several other gas engines.

CR

DaOldGuy

Got another reply today... Of the possible useful information from that reply, the Low Speed Needle should have a 1mm gap at full throttle... I have had this thing since May, the manual said not to touch the LS <factory set, prolly 1 mm at WOT> and once I finally touched the LS last month, it ran better but not correct.

I thought Magnum and ASP where the OS clones?

So this motor was 179 ish shipped.
The OS is 319 plus on Tower Hobbies
The OS has a Gas Carb and it actually has a Pump so all the drama of tank placement, loops in the fuel lines, and such all go away.
The OS is a bit heavier
Same bolt pattern as the OS 46 and 55
OS Swings a bigger prop
Pump gas, no 92 Oct required
Runs on typical 2 stroke oil, doesn't seem to demand a specific.

Starting to see the value in the extra spend.

the pope

Remember the OS is a 60 and the norvel a 40 . Is klotz castor being used by those who are having issues ? Maybe other castor is suitable but I went with what was recommended and havent had a issue other than early on which has been solved ( hopefully ) with the later production runs . To me it seems either fuel related or still with the head shims . Is the recommended plug being used . No swarf in the carb or air leaks in the lines , tank , carb etc . Shame to give up on the engine as mines been running good . Maybe sending it in for service might be a good idea . Let someone else root around with it . I found Dimitry to be a stand up guy and helpful . Cheers the pope

DaOldGuy

Yes... Klotz Benol Castor... I am a Klotz oil <synthetic> user in my gassers. I do think Dmitry is a stand up fella. and like anything new, you hate to touch and tweak anything new, and I didn't for a long time. We did finally check, tighten things,

I purchased 2 OS P3 and a OS P5, and there was a time I tried the P5 and it seemed better.

Agreed, the OS is larger and heavier then the NV, and why I have tried to get this NV to run consistently.

Dmitry mentioned all the positive reviews / comments on the motors, and I get that, but who is to say there could not be a bad patch of parts that got used unknowingly and the ones we got have issues.

hsukaria

Fellas, I got good news and bad news. First the good news: The engine I got from a friend who gave up on the GX-40 had been running great after a period of rough running on the bench and then on my Escapade for a few flights. After about a quart of gas mix of flying, the engine finally started to idle well enough to land without deadsticking. This engine had the head gasket replaced, the HSN o-ring replaced, and the aft piece of the muffler lost because the wire broke. But in the end I was getting 12K rpms with a Master Airscrew 11x6 prop. I finally thought I was out of the woods when on the last flight (always the last flight), the crankshaft pin sheared right off, and the con-rod poked through the crankcase. The crankcase is repairable since the pieces remained in place and I can coat the outside with JB Weld maybe. But I can't explain why the crank pin sheared of the crankshaft in a very clean break. This engine has not hydro-locked on me ever and I had not run it too lean either. The original owner called NV Engines about it and they told him it is because we ran it too rich and hydrolocked and no warranty coverage. It could not have been hydrolocking if I was getting 12K rpms out of it when it broke!!

So now I am torn whether I want to rebuild this thing as a gas or a nitro, or just use it as spare parts for my AX-40. I also don't know if I should replace the con-rod even though it is not busted. The brass bushing looks a bit scratched, but not sure that is normal.

What do you all think?

aspeed

I will go out on a limb, and say that there was not enough oil on the rod, which made it heat up, seize and snap off. That is usually the case of a snapped pin. I never had any snap that had a lot of clearance, but lost a couple that were too tight. At least .002" clearance is good. The oil has to get between.

hsukaria

That's what I would think but when I removed the backplate, the inside was quite oily. Maybe the bushing area and the crankpin were not getting enough oil for some reason.

Edit: I went back and looked at the crankpin and con-rod bushing and the surfaces are slightly scratched, but not enough to show any seizing. The crankpin rotates freely inside the con-rod bushing. The break is so clean between the crank and crankpin that there are no signs of bending or twisting.

DaOldGuy

I breached the discussion of sending it in and NV showing me they can get it to run. The reply back was...
"Our testing facility is in Russia. I don't think you would like to ship your engine there. But if so, it can be arranged," So I am guessing that "sending it in for service is not something that is frequently done.

11x6 is the break in prop, maybe it should not have been run 12K and that was just its limits. 8) I think I should take Dmitry up on his offer to send me the nitro parts or put a 10X5 on it and see if it will explode on the stand while on video. 8)

the pope

What happens with warranty work then ? Sounds like a cop out to me . Doesnt it work like if they import it then they have to fix it if theres a issue ? Thats good to know , I guess no more norvels for me Cheers the pope

DaOldGuy

I don't get a good feeling about Warranty work at all. I am getting the Nitro parts to see if it will run on that fuel I guess.

hsukaria

The manual says the piston/liner are not covered by warranty, which could be justified. But in the case of my engine, the crankpin broke and I am not sure it won't happen again if I buy a replacement crank.

the pope

Hi there husky , if I was u I would throw that ******* child of yours as far over the back fence as you can .That thing can be described as a p.o.s. and I wouldn't go crossing the road either if I was u with your luck. The bottom bush on the conrod didn't rotate so as to block the oil holes did it ? Your certainly taking it better than I would be .Cheers from the pope

aspeed

I still think it just did not have enough clearance on the rod to crank pin. Sometimes they are overhardened, but normally the pin gets tweaked, or the bearing spins. Bad cases the pin turns blue. If anyone throws it out, throw it my way, I will pay shipping. I can make a pin to press in. I was thinking of getting one, but the dollar here as well as the stock market in the last week, kind of put a stop to the dreams. I am in the middle of a move, and the machines may be out of service for a few months too. Mr. Pope, throwing children over fences is an old practise. Over the last 5 years or so, it is being frowned upon. Too bad. I used to scare the kid when he was bad, by telling him I would throw him in a snow bank. He always straightened up quick. I had to throw him on once. It was quite a scene. He's a good boy now.

hsukaria

Thanks popey. I am taking it well because I did not pay for it. I was helping a friend and he gave up on it and didn't charge me for it unless it would end up well. So, it failed and I don't owe him anything, although I think I will compensate him for it a little because I am using this as a learning experience in "character building". As a minimum, I can use the parts as spares for my AX=40 that I have owned for a few years with no issues.

I have to say, warranty and support was quite excellent when I bought the Norvel a few years back from Sig Manufacturing. They did everything possible to make sure that I was satisfied with my purchases from them.

hsukaria

My kids would have thought throwing them into a snow bank as a fun thing.

I priced the replacement crank and it is $35 plus shipping. So that will be about $40ish. Might be worth it if I knew it won't happen again.

The conrod bushing did not turn. I poked a pin through each oil hole to make sure they were not plugged and they were fine. Nothing seems to be out of whack as far as lubrication problems.

the pope

Just in case it may have been lost in translation I was referring to the engine being a bast##d child and to throw it over the fence .We all know bad kids should be thrown under a bus . cheers the pope

Charley

My Feedback: (2)

The 1mm info has been stated on this thread before. My GX-40 idled fine out of the box. After I took the carb apart looking for blockage I indexed the LSN to 1mm. It wound up a bit wider after tuning it.

I wrote TT, et al. Et al means, and others. We used to buy Thunder Tiger (TT) & Magnum engines. Both were considered OS clones by most modelers. Magnum is ASP, made by Sanye.

Anyway, call them what you will, I'll wait for a clone or get one from HK.

CR

Charley

My Feedback: (2)

Your scenario usually results in a broken rod, not a sheared crankpin. IME, sheared crankpins usually are the result of a seized piston.

CR

hsukaria

No seized piston in my case, perfectly smooth and was breaking in nicely until the bitter end.

Charley

My Feedback: (2)

hsukaria,

I disagree with their assessment. Unless they're claiming a prior hydraulic lock damaged the crankpin, causing it to fail later, in which case the rod would be bent. Is the rod bent? NV parts come from a address in CA. Too bad they don't have someone there to evaluate returned engines. If mine blew up I wouldn't throw more $$ at it.

BTW, what phone # did the PO call?

CR