Evinrude 50 4 stroke 1999 been setting, need to restart suggestions/ guidence

[Rickf]

Evinrude 50hp 4 stroke (Suzuki)1999, had issues with many years ago #3 cyl, mis sfire and cold temp compared to other cylinders, and shoved it to the back of yard till I got time to play with it, now semi retired, it needs to go scrap or repaired and replace my 35hp 2 stroke on the back of my other pontoon boat.
Last week, With no fuel, fogged cylinders, let set for 20 min, ran compression test 1: 60-195, 2: 60-195, 3: 60-180, not perfect, not overly bad, will live with.
Previously had to Suzuki shop 2x said no issue ran their computer, 2nd time said bad cam sensor, replaced no help,
IN THE PAST
I've swapped coils, replaced coils, plugs, swapped injectors, replaced secondary fuel pump electrical failure), all to no avail, thinking it was probably a bad computer, and it still may be, but I'm going to start the testing over, since the compression is still good. I'm going to do some further testing to scrap or save.

I'm open to any suggestions or ideas. sorry to be so long, just trying to answer all questions in advance.
Things I'm going to do:
pull elec fuel pump and clean well and all area.
Clean and flush with cleaner and air all fuel lines, tank and all fresh fuel.
Pull all injectors and make sure screens are clean, can soak in carb cleaner if that is suggested and safe.
Is there a way to safely test the Injectors for flow?
There is no corrosion on the ECU pins.
I have a noid light to test Inj signal.
I have a spark tester that I can test for a large spark
Any rotation will be done with water on to save water pump.
Will pull and replace water pump impeller if all tests are good
Replace fuel filter on side.
Should I replace the fuel filter inside of the fuel pump or clean and reinstall?
Of course oil and filter change before any further testing.
Change lower unit oil with water pump
Estimate time on this engine is less than 100 hours, I knew the couple that had it since new.
Any other Ideas or suggestion missed items, would be greatly appreciated.
Thanks again in Advance for them,
Rick in Ga

 

[Crosbyman]

first thing is to get a manual and compare results to specs. it may flag a problem more than swapping or guessing but... ex: see sect 3.59 on injector electricaland physical tests and..NOID lamp checks
download this manual

Repair Manuals G1 Motors & Gearcase - Google Drive

drive.google.com

pull elec fuel pump and clean well and all area. (measure ohms on pump)
Clean and flush with cleaner and air all fuel lines, tank and all fresh fuel.
Pull all injectors and make sure screens are clean, can soak in carb cleaner if that is suggested and safe. (Measure ohms per injector.. if OPEN-JUNK check that injectors click "no click ? try cleaning " ) see utubes on inj. work u could do but professionnal inj. jobs are best)
Is there a way to safely test the Injectors for flow? see utubes couple of videos showing basic flushing)
There is no corrosion on the ECU pins. (Check & apply contact cleaner check ALL connection points incl. connectors at both end of inj, coils, pump etc... "many years" sitting is a long time !)
I have a noid light to test Inj signal. (report findings here)
I have a spark tester that I can test for a large spark (report findings here)
Any rotation will be done with water on to save water pump.
Will pull and replace water pump impeller if all tests are good (replace anyway)
Replace fuel filter on side. ok
Should I replace the fuel filter inside of the fuel pump or clean and reinstall? cleaning filtersshould do
Of course oil and filter change before any further testing. OK
Change lower unit oil with water pump (replace anyway)
Estimate time on this engine is less than 100 hours, I knew the couple that had it since new. (should be able bring it to life...if nothing major)
Any other Ideas or suggestion missed items, would be greatly appreciated.
(easy stuff first...)

 

[Rickf]

Thanks Crosbyman,
answering your questions to My Question, that will also help someone else.

pull elec fuel pump and clean well and all area. (measure ohms on pump) Ohms forgot to check, powered direct to pump, it was frozen, pulled pump and found corroded not sure of cause, see picture, suggestions on stopping continued corrosion of bracket and best idea for cleaning, no damage to housing.
Clean and flush with cleaner and air all fuel lines, tank and all fresh fuel.
Pull all injectors and make sure screens are clean, can soak in carb cleaner if that is suggested and safe. (Measure ohms per injector.. if OPEN-JUNK check that injectors click "no click ? try cleaning " ) see utubes on inj. work u could do but professionnal inj. jobs are best)resistance
Is there a way to safely test the Injectors for flow? see utubes couple of videos showing basic flushing) Injectors 14.4 ohms but 1 loud clicker and 2 dull injectors, contacted the pro at Duvall's marine who had a cleaner machine and he said with that type of screen there was really no way to properly clean them and the were about the same price on Amazon as the cleaning $20. ea ordered 3 for $60.
There is no corrosion on the ECU pins. (Check & apply contact cleaner check ALL connection points incl. connectors at both end of inj, coils, pump etc... "many years" sitting is a long time !)all clean no corrosion, Ohmed all the systems and the were within factory spec checked from the ECU connectors
I have a noid light to test Inj signal. (report findings here)All good
I have a spark tester that I can test for a large spark (report findings here)all would jump a 20 on the spark tester which is electronic spark
Any rotation will be done with water on to save water pump.
Will pull and replace water pump impeller if all tests are good (replace anyway)
Replace fuel filter on side. ok changing both external fuel filters
Should I replace the fuel filter inside of the fuel pump or clean and reinstall? cleaning filters should do, off but not pulled apart yet
Of course oil and filter change before any further testing. OK
Change lower unit oil with water pump (replace anyway)
Estimate time on this engine is less than 100 hours, I knew the couple that had it since new. (should be able bring it to life...if nothing major)
Any other Ideas or suggestion missed items, would be greatly appreciated.
(easy stuff first...) so far other than Maintenance items the fuel pump was a surprise (corrosion any way) and injectors
Note for readers who have this engine on the bottom of the hi press pump chamber there is a screw with a hose attached to it that goes straight out the bottom as an external drain recommend opening screw a couple of turns and draining fuel at end of season get rid of any possible fuel/water and save the corrosion like I had, I had a fuel/water combination come out of mine after setting for a time. Will post results after I get it all back together
Thanks again to Crosbyman for the additions to my list

 

[Crosbyman]

some pumps... have ben known to be revived on ETEC engines by short reverse polarity kicks and feeding the pump some oil.. let it soak and retry inverse polarity kicks... then forward polarity
some have even boiled the pump (in a plastic bag) but I never tried it myself.

injectors can be cleaned in good injector shops if not RIP'd ...always replace them in their original position !!