one HAL 9000 opinion...fwiw
POST YOUR MDL #
Yes — on the
1994 Evinrude E140CXERE carbureted V4, that combination of
hard starting + intermittent rough idle + dying points me more toward a
fuel/low-speed carburetion problem than an ignition problem, although ignition should be checked too.
I'd investigate in this order:
- Carburetor low-speed circuits
- A partially plugged idle/low-speed passage can cause exactly this.
- The engine may run reasonably once the throttle is opened, yet be difficult to start and die at idle.
- If one carburetor is affected, the engine can idle very unevenly.
- Choke/enrichment system
- If it is hard to start cold, check whether the electric primer/enrichment system is actually supplying fuel.
- If it starts only after repeated priming, that's a strong clue.
- Conversely, excessive enrichment can make it load up and die.
- Carburetor synchronization/link-and-sync
- On this V4, the four carburetors need to begin opening together and the idle timing/throttle relationship must be correct.
- An incorrect adjustment can produce a very unstable idle.
- Fuel supply / air entering the fuel system
- Check the primer bulb, fuel hose, connections and fuel filter.
- A small air leak can make the problem intermittent.
- Watch the primer bulb while the engine is running; if it repeatedly collapses, that's particularly significant.
- Ignition at idle
- Check all four plugs for condition and compare them.
- An intermittent coil or ignition component can cause an occasional dead cylinder and make the engine suddenly shake or die.
- A spark-gap test is much more useful than simply looking at the spark at the plug.
- Compression
- I'd do this before getting too deep into carburetor work. Four relatively even readings are what you're looking for.
A very useful test
When it is
running rough and about to die, carefully give it a
small amount of choke/enrichment.
- If it immediately improves: very strong indication of a lean fuel condition — carb low-speed circuit, fuel restriction or air leak.
- If it gets worse: you're probably not dealing with a simple lean condition.
- If there is little/no change: ignition or synchronization becomes more suspicious.
Also, if it
dies suddenly as though someone switched the ignition off, rather than gradually coughing and slowing down, I'd move ignition higher on the list.