posted
After 2nd phase of running in on C12 enigne, the pull starter failed. Investigation revealed that there is some heat damage to the outside end of the one way bearing. (The plastic casing was distorted). This is preventing the rollers to move and lock on application of the starter. Anyone had this problem? Question: Can I just replace the bearing, or does the outer crank/bearing and shaft need to be replaced? (Oh yes top tip - when removing the pullstarter ensure that the coiled spring does not leap across the room!)
IP: Logged
PembertonH
unregistered
posted
This RB Pull starter problem sounds very familiar. I recently had a similar challenge. On 13 April 2002, I bought a new nitro engine for my 1/10th scale Yokomo GT-4 touring car... an RB Concept C12, 1700-0104 engine with Pull-starter. RB claims that the pull-starter used to start this engine is of very high quality and designed for the use with this engine. However, the pull starter on my "new" RB motor failed on day 2. It worked fine on day 1 when I went through my engine break-in procedure. Yet on day 2 I get one compression "pop" and then the cord pulls freely through it's length. My engine will not start like this. I contacted RB Concept via e-mail, but their response was of no help. Thereafter I contacted some Nitro RC guru's at http://www.nitrorc.com and they provided the following assistance:
"Sounds like the 1-way bearing is slipping already. It doesn't mean there's anything wrong, just that oil and fuel may be seeping out the rear shaft bushing, getting on the starter's shaft. I'm surprised it happened so soon. I made it through about 1.5 gallons before my 1-way had started slipping. It got to a point where before I could start it, I had to remove the pull-start from the rear of the engine, clean off the shaft and inside of the 1-way, then re-assemble. Total pain in the a$$. Instead of using the pull-starter, I just left the pull-start housing off and used a cordless drill will a nut on the 1-way. Seemed to help, but most importantly it made cleaning off the shaft and bearing much easier."
I have taken off the pull starter and cleaned the shaft/one way bearing very well with nitro-cleaner. It solves the problem for a short while, but it'll slip again... and you'll be cleaning it again in order to get your engine started.
I wonder if RB Concept will provide us with a real fix to this problem?
posted
The one-way bearing slipping is indeed a problem and there is no real miracle solution I can give to you beside the cleaning method.
The main problem is that the oil used in the fuel for the engines seems not compatible with the function of the one-way bearing and since the one-way bearing is in contact with the fuel, you can guess what happens. Now we could try and find another construction for the pull starter but if this was so obvious it would have been made already, so this is where we at this moment.
posted
Thanks fo rthe feedback guys, very reassurring in a way to know I am not alone. I would imagine given the variability in time to slip that the problem is a tolerance issue of the shaft to bearing (a small shaft and large bearing must have coincided in my unit for such an early problem) I will ask if I can try with another shaft and bearing, failing that I guess I need to use a starter box. I'll keep you posted
Oops forgot to add, tried the cleaning thing 2 or 3 times and only got three pulls before it went loose again!
UBBFriend: Email this page to someone!
