1994 140hp evinrude

[Mrobi]

I have a 1994 evinrude 140hp. I took my boatvout yesterday and could only reach 36mph/4100rpms. It was hitting 43mPh/5200rpms. With in the last year I have replaces plugs & wires, power pack, themostat, coil packs, impeller, rebuilt all 4 carbs(all chasing another problemthat y'all help me remedy) and all seals in the lower unit. The only thing I did before I noticed it was not reaching WOT, was replaced the fuel quick disconnect with a permanent connection because I started losng prime after adding the quick disconnect. Im no longer losing prime but now I can't reach wot speeds. Any suggestions

 

[saltchuckmatt]

I'm guessing you lost one cylinder somehow.....spark, fuel, compression....something. what story do the spark plugs tell?

 

[racerone]

Nobody can see, touch or hear your motor !----You need to post information.-----The 2 most elegantly tests are #1 compression test, post the actual values here.---#2 is a spark test , does spark jump a gap of 3/8" or more on each lead, yes or no?----Then again it could be the flywheel key sheared.-----Or seagull feather stuck in a reed valve.

 

[Mrobi]

I'm guessing you lost one cylinder somehow.....spark, fuel, compression....something. what story do the spark plugs tell?

Thanks

I'm guessing you lost one cylinder somehow.....spark, fuel, compression....something. what story do the spark plugs tell?

The bottom starboard plug appeared fouled but definitely has spark, lots of spark. The other 3 plugs looked ok. Gonna rent a compression tester tomorrow.

 

[Mrobi]

Nobody can see, touch or hear your motor !----You need to post information.-----The 2 most elegantly tests are #1 compression test, post the actual values here.---#2 is a spark test , does spark jump a gap of 3/8" or more on each lead, yes or no?----Then again it could be the flywheel key sheared.-----Or seagull feather stuck in a reed valve.

Thanks

The bottom starboard plug appeared fouled but definitely has spark, lots of spark. The other 3 plugs looked ok. Gonna rent a compression tester tomorrow.

Thank you

 

[saltchuckmatt]

Thanks

The bottom starboard plug appeared fouled but definitely has spark, lots of spark. The other 3 plugs looked ok. Gonna rent a compression tester tomorrow.

Spark means nothing....buy an inexpensive spark gap tester like Racerone suggested...cheap at any auto parts store. Could be an ignition coil.

 

[Mrobi]

Nobody can see, touch or hear your motor !----You need to post information.-----The 2 most elegantly tests are #1 compression test, post the actual values here.---#2 is a spark test , does spark jump a gap of 3/8" or more on each lead, yes or no?----Then again it could be the flywheel key sheared.-----Or seagull feather stuck in a reed valve.

So im understanding you. I need to spread the gap from .030" to 3/8(.375)" and see if its still sparking?

 

[racerone]

Sparkplugs are not used for this test.----Buy a spark tester.----Or use some wire / glue and carboard to make one.

 

[Mrobi]

Sparkplugs are not used for this test.----Buy a spark tester.----Or use some wire / glue and carboard to make one.

Sparkplugs are not used for this test.----Buy a spark tester.----Or use some wire / glue and carboard to make one.

Will by a spark test when I rent the compression tester

 

[saltchuckmatt]

Will by a spark test when I rent the compression tester

 

[Mrobi]

Picked up exact spark tester.
Cylinder 1& 2 steady spark motor started and ran briefly
Cylinder 3 & 4 not as steady. Cylinder fired once on 1 and not at all 3. Replaced new coils with old coils on 3 and 4. Motor will start on all now:
Compression numbers:
Cylinder
1: 100
2: 110
3: 100
4: 110

 

[saltchuckmatt]

S

Picked up exact spark tester.
Cylinder 1& 2 steady spark motor started and ran briefly
Cylinder 3 & 4 not as steady. Cylinder fired once on 1 and not at all 3. Replaced new coils with old coils on 3 and 4. Motor will start on all now:
Compression numbers:
Cylinder
1: 100
2: 110
3: 100
4: 110

So 3/8 gap on all cylinders? Good blue spark?

Compression states well used.

Take it out for a spin.

 

[Mrobi]

S

So 3/8 gap on all cylinders? Good blue spark?

Compression states well used.

Take it out for a spin.

Will do tomorrow. Do you know what the factory compression numbers should be. Just googling ive seen 95-115 & 120-140. Quite a discrepancy

 

[saltchuckmatt]

95 to 140...

Could be your compression tester. I have 3...they all read differently. Check it right after you've earned it up.

 

[Mrobi]

95 to 140...

Could be your compression tester. I have 3...they all read differently. Check it right after you've earned it up.

Will do thanks

 

[Mrobi]

Im back baby. 43 mph @ 5100tpms. Thanks for all your help

 

[saltchuckmatt]

Im back baby. 43 mph @ 5100tpms. Thanks for all your help