Engine Flaming Out
#1
Engine Flaming Out
I know it's difficult to determine an engine problem on the internet, but maybe someone has had a problem similar to mine.
At the track today i installed a fresh conrod in my Caster Grenade. It ran fine during practice, but then starting to flame out during the heats. We thought it was a clutch spring problem so we changed those. That didn't help. In the main it was apparent the coming out of the straightaway when i let off the throttle, the engine would die. We kept adjusting the tune, but the same problem occurred. Sometimes i could barely get off pit lane. So when i let off the throttle the engine acted like it would just load up with fuel, and stall when i gave it throttle. One person said it was lack of compression, however the engine does have some flywheel resistance when hot. Others said it was rod/crank slop. Which would have to be the crank since the rod is new.
If you having any suggestion/ideas please feel free to post them.
Thanks
At the track today i installed a fresh conrod in my Caster Grenade. It ran fine during practice, but then starting to flame out during the heats. We thought it was a clutch spring problem so we changed those. That didn't help. In the main it was apparent the coming out of the straightaway when i let off the throttle, the engine would die. We kept adjusting the tune, but the same problem occurred. Sometimes i could barely get off pit lane. So when i let off the throttle the engine acted like it would just load up with fuel, and stall when i gave it throttle. One person said it was lack of compression, however the engine does have some flywheel resistance when hot. Others said it was rod/crank slop. Which would have to be the crank since the rod is new.
If you having any suggestion/ideas please feel free to post them.
Thanks
#2
thats usually a sign of low compression and or crankpin wear,i would lean to the crankpin wear.
also is it running hot? if so rear bearing is about to drop.
me personally i would pull it out and strip it down to inspect.
also is it running hot? if so rear bearing is about to drop.
me personally i would pull it out and strip it down to inspect.
#4
cool let us know..
also measure all the way around the pin.
also measure all the way around the pin.
#5
I just took the backplate off and checked the slop. I can see where the crank pin moves inside the rod, and squishes fluid around in between the two. The rod is brand new, so wouldn't that mean the crank pin is worn since it has some slop between it and the rod?
#8
Tech Fanatic
iTrader: (5)
I had the same symptoms with my engines, it turned out to be the high speed needles o rings. they were worn out and the needle was spinning out from the vibration of the engine. I was able to put the buggy up on the bump box give it throttle and watch the needle turn all the way out. a new set of o-rings and i was good to go. i run a OD ss .21.
#9
Tech Prophet
iTrader: (96)
Crank measurement to look for and be within tolerance is 4.92mm or better , measure in many different spots on the crankpin .
Hope this helps ,
Monty
And btw , the crank/rod fit has to have a little play so oil can get in there :-)
#10
Honestly, the rod/crank feels the same as it always has, if not better since i installed the new rod. I think the problem is the lsn because it's extremely easy to turn. I read in an rc car action magazine to put a light bit of blue loctite on the threads. But i don't trust putting locktite on my engine. I'm going to get some new o-rings and give it another shot.
#11
Tech Prophet
iTrader: (96)
Honestly, the rod/crank feels the same as it always has, if not better since i installed the new rod. I think the problem is the lsn because it's extremely easy to turn. I read in an rc car action magazine to put a light bit of blue loctite on the threads. But i don't trust putting locktite on my engine. I'm going to get some new o-rings and give it another shot.
pm me if you need one ,
monty
#13
would a O.S. carb work as well?
#15
you will see the rod slop more at TDC when rotating the crank back and forth,
agree you cant beat a novarossi carb.
btw the 14mm novarossi crank will work in there also.
agree you cant beat a novarossi carb.
btw the 14mm novarossi crank will work in there also.