1985 Evinrude 140 V4 running very rough/ hard to start

homer79

Recruit
Joined
Apr 14, 2023
Messages
2
Hi this is my first post here. Just recently purchased a Bass tracker with a 1985 140 hp Evinrude. Didn't start at first. It's been sitting for quite awhile. I drained the fuel tank,
put new fuel in,
cleaned the fuel filter,
replaced main fuel lines
Replaced spark plugs
Sprayed lube in the pistons
Cleaned the carbs
Checked all jets
Took VRO pump apart and replaced diaphrams (old ones were cracked up)
Checked spark on all plugs
Dumped in some seafoam
The plug for the VRO pump was very slightly corroded inside, and I cleaned it a bit and filled it with dielectric grease.

Result is it'll fire up, but run like it's only firing every odd time. Dies frequently. Then all at once it'll catch and run like a dream, only it won't idle down but stay very high idle. Before I replace the diaphrams it seemed to only stay running with the pumping primer bulb.
Would anyone have any ideas what to check next? Since electrical issue or something?
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,838
Welcome to iboats

First things first, what are the Compression #s
You say it has spark on all cylinders. Is the spark strong enough to jump a gap of 3/8"?
You said you cleaned the carbs. Did that include removing them, taking them apart, checking/adjusting the Floats, removing all the plug disks to be able to clean out all the passages? If you removed the carbs, did you sync all the carbs to each other and to the Spark Advance?
The gasket/seals between the Carb and the Intake in good condition?
The Carbs are fully closed at idle, and the idle speed is controlled by the Spark Timing.
When you had the VRO Pump apart, were all the O-rings in good condition?
 

homer79

Recruit
Joined
Apr 14, 2023
Messages
2
Welcome to iboats

First things first, what are the Compression #s
You say it has spark on all cylinders. Is the spark strong enough to jump a gap of 3/8"?
You said you cleaned the carbs. Did that include removing them, taking them apart, checking/adjusting the Floats, removing all the plug disks to be able to clean out all the passages? If you removed the carbs, did you sync all the carbs to each other and to the Spark Advance?
The gasket/seals between the Carb and the Intake in good condition?
The Carbs are fully closed at idle, and the idle speed is controlled by the Spark Timing.
When you had the VRO Pump apart, were all the O-rings in good condition?
Thanks, so I did take the carbs apart, but didn't do anything with the floats. I did note that all the bowls were full but didn't take them off. I really don't know much about syncing the carbs, is that a manual adjustment somewhere?
I don't have a compression tester so didn't check that.
The orings seemed fine, and I replaced everything that came with the new diaphrams.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,838
Any time the Carbs are R&Red, the linkages between each other, and with the Spark Advance Plate, need to be verified and adjusted if need be.
You need to get a Factory Service Manual specific to you model and year of Engine.
How did you manage to take the carbs apart, without taking the Fuel Bowls off?
Spraying Carb Cleaner into the carb while engine is running doesn't do much except cleans the Throttle Plate. a bit...

You say it is an 85. Did it have 4 single barrel carbs, or 2 barrel?
 
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