Hi All,
Trying to get a feeling from everyone as to what is wrong with my O.S. 21VZ-B V-Spec. Running 30% sidewinder and no changes to shims or other.
Issue Description
Recently in previous runs the engine has flamed out two times before this issue became chronic, but after starting up it seem fine the rest of the time. Prior to the two recent times this engine has never flamed out. Last Saturday engine flamed out constantly.
First race, went about 5 minutes then landed a jump and flamed out. Restarted... flamed out after about a lap on flat spot, restarted... flamed out going down the pit ramp.
Troubleshooting: Checked glow plug. Appeared perfect, but swapped out for new plug anyway. Ran on side and checked engine temp, running 210... target I usually go for is 220-230.
Second race, ran for about 3 minutes, flamed out at end of straight, restarted... flamed out at 1/2 a lap, restarted... again flame out at end of pit lane.
Troubleshooting: Re-tuned engine and bench ran engine. Ran for about nine minutes with no issues. Checked engine temp, 215.
Third race, ran for about 1 minutes, flamed out at end of straight, restarted... flamed out at 1/2 a lap, restarted... again flame out at end of pit lane.
Potential Diagnosis
Speaking to others at the track I got two potential issues.
Discounted issues verified by others
Very confident engine is tuned properly
No tank or line leaks
Carburetor and case cover seals appear good
Possible Issue #1: Dirt in a needle valve is causing the flameouts. I keep my car pretty clean, but I do recall seeing some dirt in the high mix value and using a can of air to clear some dirt.
Possible Issue #2: Upon inspection there is oil/fuel coming out around the seal to the exhaust manifold. The seal does appear worn and the fit is loose. Does not have that snug feel. Could this cause flameouts?
Someone Else?: Asking you, is there something I/we have not thought of?
Thanks to all those who post. I'm in the process of learning nitro engines and the people here offer some great feedback for learning.