Frustration with motor has taken me back to a newb...

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jaygreig

jaygreig

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Terre Haute, Indiana
I put a 35mm piston/+2mm stroke stuffed crank top end on a 2 bolt CY. This is the ESP ported kit from DDM. Installed with Losi tuned pipe, new Walbro 990, fresh 93 fuel, Klotz oil, Killer RC on a DX3R tx with a 3300T rx. I used the DDM graphite/steel crank seal, Fast eddy bearings, and new CY oil seals, and I believe a 0.040 head gasket.
I am doing my usual put way too much money into the Losi before I sell it...I got everything together, fueled it up and it started on the 4th pull...was purring right along and as soon as I gently bumped the throttle, it dies. It restarted on the second pull and ran for another few minutes until I bumped the throttle again. This time started on the first pull...this time I opted to give it about a 1/4 throttle blip to see what it would do...low and behold it dies again...very abruptly...no bogging or loading up. I am at a loss...I have finally gotten to where I trust (mostly) my mechanical skill and knowledge with these magnificent machines, and here I am asking for help with the overwhelming feeling that I am overlooking something obvious/simple. Any help would be appreciated.

Yes battery is fully charged fresh off the charger and is a 5700mah 2s 30c lipo
 
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What are the Carb. settings ?
1st Sounds like a lean high speed needle could be to blame.
Readjuct to factory 1 1/4 low and 1 1/2 high settings and retry.
2nd thing to try is to disconnect the kill swich to eliminate that from being a problem.

Fill me in from there & I will certainly try to help.
 
Did u put the piston on the right way? Sounds like a carby problem though... Check to see if there are any air leaks as well.
Good luck
 
I'm not all that engine savy so dunno if this matters but on all of the descriptions to ESP's kits it mentions using a .020" gasket. Could the .040" be the problem? Maybe someone more knowledgeable can answer that.
 
See the red highlighted text that explains why you still use the stock .020 gasket with this kit.
This I guess could be a problem with the install done in the Original post, assuming that this is the kit used, but he did not say 36mm.
He did indicate a 35mm, which would be this kit: http://www.davesmotors.com/race-ported-cy-35mm-26_9cc-big-bore-kit.html
I the 35mm kit was used, you would be required to use a .040 gasket to add clearance for the extended stroke of the crankshaft.
Would really need to know for sure what kit was used to give good advise on how best to correct this problem, or start troubleshooting anyway.

If displacement is what you crave, look no further. This ESP modified & ESP Race Ported big-bore combo kit will allow you to convert your current engine into a 30.5cc performance monster. Feel the power that only a larger engine can provide. This kit is a TORQUE MONSTER, with killer low end and midrange power. ESP modifies this cylinder by machining at the head. The stock 36mm cylinder does not have room for the longer crankshaft in this kit, so ESP has machined out the proper spacing. This is a more efficient and reliable solution than stacking gaskets to achieve the needed space, as there is proper spark plug clearance and the piston ring remains in the well-plated area of the cylinder. The squish band is cut so there will be .020"-.025" of squish (using the stock .020" cylinder gasket), and the combustion chamber is machined to get the compression ratio down to 14:1 for running on premium pump 91 or higher octane gasoline. The head geometry is reshaped to the proven standard 'hemisphere' shaped combustion chamber, and the squish area equals 50% bore area, for more effiecient burning. These ESP modified cylinders are then race ported by ESP - intake, exhaust, and transfer ports have been enlarged/reshaped for more fuel/air flow and hence more power. Kit includes ESP modified + ESP ported 36mm cylinder, 36mm piston, piston ring, piston pin and two pin washers, circlips, two cylinder bolts, insulator gasket, and CMR7H spark plug. Increases your engine displacement to 30.5cc (36mm bore) when used with a 30mm stroke crankshaft. This kit is not recommended for use with a 28mm or 29mm stroke crankshaft, as the modifications are specially tailored to work with a 30mm stroke. Increases engine power SUBSTANTIALLY - estimated engine power output is 4.3+ HP. This high-performance product requires 91 octane (using the R+M/2 octane rating method) or higher fuel, and comes without warranty. Fits Zenoah G23LH / G230RC / G260RC engines when a +2mm (30mm total stroke) crankshaft is added. Also fits Chung Yang CY23RC / CY26RC / CY27RC / GP290 engines when a +2mm (30mm total stroke) crankshaft is added. Bolts directly on to Chung Yang CY29RC engines, as this engine features a 30mm stroke crankshaft as stock. Bottom line - to install this kit on any engine except a CY29RC, you must purchase a +2mm crankshaft. For Scooters: Fits any scooter using one of the above engines. Fits Sport, Liquimatic, Bigfoot, X-ped, Super X-ped, Super Bigfoot, Go-Quad, Super Go-Quad, Go-Quad 30, GSR26R, GSR29R, and Homebuilders Kit. For R/C: Fits a wide variety of 1:5 and 1:6 R/C cars, planes, boats, and helicopters. Same mounting dimensions as Zenoah G230RC / G260RC. For cars - fits FG: Marder, Leopard, Monster Beetle, Monster Truck, Stadium Truck, and Pajero. Also fits Smartech Traveler, Firehammer, XTM, Carson Attack, HPI Baja 5b, and other large scale RC cars. Must be used together with a 30mm stroke crankshaft.
 
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I agree with you, it could be a problem depending on what kit he actually used.
Lowering the compression would be one affect, changing port timing would aslo be a problem by adding a thicker gasket.
I would think that it would not want to start at all, instead of start & then die when hitting the throttle.
Sounds more like a carb. adjustment issue to me, but ... Could be a kill switch issue ... Or ... Whatever.

Where did you go Jay ? ;)
 
It's awesome seeing some of the responses I got for this. Looker, I think we really need to meet up one day so I can pick your brain on a few of my engine projects. How far are you from Terre Haute?

The update will nearly kill me to post, but I figured out what the problem is..it was something so obvious I can't believe I didn't see it. So as I was making another attempt to check over some of the seals and checking spark etc. I had moved to the other side of the Losi on the stand...I did my usual trick of sticking the battery compartment section of my transmitter in my back pocket to get both hands free and bumped the throttle...out of the corner of my eye I see a light blink...the led light that I mounted to the battery box lid...the kill switch indicator. So yeah...the throttle servo was browning out the rx and showing a glitch/voltage drop to the Killer. I cannot believe the whole time I had been messing with it that I never noticed the light blink. (Hidden by the pipe) I'm not sure what is causing the stock throttle servo to draw so much, but at least I've figured out where the gremlin was. I disconnected the super bee and the engine came up throaty and strong...
So thanks to everyone who gave me a fresh "look" at it...it never ceases to amaze me the wealth of knowledge on this forum
 
The question still remains, did you use the correct gasket? Seems silly to buy a ported kit and then use a thicker gasket then intended. Sure it will run, but it would most def be better to put the right one in. Glad you found the glitch though it can sure be annoying when you cant get them running.
 
jaygreig said:
It's awesome seeing some of the responses I got for this. Looker, I think we really need to meet up one day so I can pick your brain on a few of my engine projects. How far are you from Terre Haute?

The update will nearly kill me to post, but I figured out what the problem is..it was something so obvious I can't believe I didn't see it. So as I was making another attempt to check over some of the seals and checking spark etc. I had moved to the other side of the Losi on the stand...I did my usual trick of sticking the battery compartment section of my transmitter in my back pocket to get both hands free and bumped the throttle...out of the corner of my eye I see a light blink...the led light that I mounted to the battery box lid...the kill switch indicator. So yeah...the throttle servo was browning out the rx and showing a glitch/voltage drop to the Killer. I cannot believe the whole time I had been messing with it that I never noticed the light blink. (Hidden by the pipe) I'm not sure what is causing the stock throttle servo to draw so much, but at least I've figured out where the gremlin was. I disconnected the super bee and the engine came up throaty and strong...
So thanks to everyone who gave me a fresh "look" at it...it never ceases to amaze me the wealth of knowledge on this forum
Click to expand...

1st - I am literally about 7 miles from LargeScaleRC, so being as you have been there, I am about less than 10 minutes due East from the tracks.
Would be great to meet up sometime.
I have built most of my own engines, for the last 8 years or so, and had many Very good performing combos.
It is very strange that the throttle servo is pulling enough current to brown out the receiver enough to engage the kill switch.
That alone really make me wonder.
I have a specialty R/C tool here, to test things just like what you are experiencing, which checks the amount of current draw of servos.
It is great that you found the problem, and worked out a solution for now.
R/C is a constant troubleshooting hobby. ;)
 
Glad you found the problem, you should pick up a buzzer for the kill switch. I had a similar issue a week or 2 ago. Start and idle no prob but give it gas and it would die. Did this a few times until I finally heard the buzzer over the noise of the others cars. Come to realize I had a low battery. Maybe a capacitor would help prevent the brown outs? or you could try lowering the low voltage setting on the super bee so you can still have the remote kill option.
 
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