Trouble starting on lake - 200 efi

[Too fat 2 fish]

Got a 94 Merc 200 efi xri motor. Starts right up when I launch. Run a while, then fish a while = hard to start.
When it does start, seems rich - lot of smoke and strong fuel smell. Runs fine when you give it some throttle.
Have replaced plugs, primer and all fuel lines. Fuel was also drained and refilled. Thanks in advance for any help

s/n is 06145588

[JOE54]

sounds like internal fuel leak to crankcase

[Too fat 2 fish]

sounds like internal fuel leak to crankcase

how would i test for that? also, compression is ok

[JOE54]

fuel psi test, inspect pump diaphragm,inspect injection for leaks in manifold for starters

[83ebbtide]

Any more news on this subject? I am having nearly the identical issue. Mine doesn't smoke a ton or have a heavy fuel smell.

[JOE54]

make sure electric pump running when no start

[Too fat 2 fish]

Any more news on this subject? I am having nearly the identical issue. Mine doesn't smoke a ton or have a heavy fuel smell.

I installed fuel/water separator + fresh plugs. Tiny amount of water in separator, plugs were wet with oil but motor hadn't been run in a week. Could be injecting too much oil? Causing it to leave unburned fuel? Going out tomorrow and will update.

[Too fat 2 fish]

I installed fuel/water separator + fresh plugs. Tiny amount of water in separator, plugs were wet with oil but motor hadn't been run in a week. Could be injecting too much oil? Causing it to leave unburned fuel? Going out tomorrow and will update.

Had these checked - all OK:
fuel psi test, inspect pump diaphragm,inspect injection for leaks in manifold for starters

Have run last 4 trips with no problem starting but still have heavy smoke and strong fuel smell.

Should I consider bypass oil inject and go to premix? What's life span for injection system?

[TX Cranker]

Had the same issue not long ago, but on a carb 175. Rebuilt the fuel pump and changed the primer to a genuine Mercury bulb.

[JOE54]

would not delete oil inj,make sure oil check valve in working properly at vst, not allowing oil to leak into vst or fuel to leak out into oil hose, known problem, on 94 if never replaced id do it reguardless

[Too fat 2 fish]

would not delete oil inj,make sure oil check valve in working properly at vst, not allowing oil to leak into vst or fuel to leak out into oil hose, known problem, on 94 if never replaced id do it reguardless

thanks Joe. oil check valve is original, I'll replace it

[EuropeanAM]

If you continue having problems, have someone check with the CDS (or a DDT) to make sure the temp sensors are reporting accurate temps (preferably check with engine cold).

IAT problems are becoming quite common.

[sleeper bird]

If you continue having problems, have someone check with the CDS (or a DDT) to make sure the temp sensors are reporting accurate temps (preferably check with engine cold).

IAT problems are becoming quite common.

mind me asking what IAT stands for?

[JOE54]

INTAKE AIR TEMP

[Too fat 2 fish]

thanks Joe. oil check valve is original, I'll replace it

Put on new check valve. Old one had indeed failed. Air could easily flow both directions
Try to get on the water soon will report results

[JOE54]

will be much better

[Too fat 2 fish]

Thanks Joe! New oil check valve made all the difference. Cost less than $15 and only minutes to swap out. Highly recommend others do the same

[JOE54]

welcome/ probly thousands bad that folks don't know about, I check every one that comes in my shop

[EuropeanAM]