coil problems or other issue??

[JT!]

well, i guess it had to happen, it's dieing. (1971 evinrude 50 selectric)​

i was booting along, at 49km/30mph and *whump* the boat slowed to a crawl.​

i brought it down to idle speed, popped it in neutral and went to look for weeds, cause it felt like i just plowed into a wad of vegetation. nothing there. water pump was operating ok as well.​

then i try moving again, 1/8 throttle ok, 1/4 ok, and then at a 1/2 throttle it bogs down.​

bring throttle back a bit to 1/4 and it recovers with a slight vibration.​

give it gas, it accelerates for a second then bogs, i pull back, and it idles healthily. i limped it back to the trailer and brought it home.​

i checked my 2 new sparkplugs; top cylinder's plug is normal to slightly dark, wet. bottom plug is wet, and barely carbonized.​

both of the old plugs, 5 hours use ago, were both uniformely black.
both my plug's coils have hairline cracks in them. they will be changed.​

is there anything else i should check out? or can i attribute my situation to coils alone? do my symtoms sound similar to anything else?​

 

[tashasdaddy]

Re: coil problems or other issue??

coils or carbs. with cracked coils you new it was going to leave you floating one day.

 

[JT!]

Re: coil problems or other issue??

Catalog Part NumberDescriptionQuantity Evinrude 0580821 COIL ASSY. 2
______________________________________________

how does Joe Boater (me) find the newest part #'s
the BRP site lists the original part number.

yet i found different models on the web that supposedly supercede the original OEM

i think newer is better, so where do i find the most recent part numbers​

 

[JT!]

Re: coil problems or other issue??

i found some coils locally for a decent price, new.

is it normal for you to be able to idle on bad coils, then they fail at higher rpm's?

i'm just wondering if i need to get other things while at the shop. the carbs were thoroughly cleaned and new jets installed, less than than 10 engine hours ago.

what worries me is the 1 plug that was not sooty, and was wet looking. how can i run on 1 cylinder at WOT and not notice a bad cylinder. can anyone advise on the plug issue?​

 

[JT!]

Re: coil problems or other issue??

both coils replaced and its still running on one cylinder??

one plug is wet and barely carbonized, the other is black and sooty.

wot = 8mph
1/2 = 8mph
1/4 = 8mph

it ran fine until i ran 3/4 throttle it for 5 minutes or about a 1 mile

suddenly gets weak and i have to pull throttle back.

the primer bulb on the fuel hose is very soft, but pumping it doesnt help at all.
i'm pretty sure i'm missing spark.

where should i start to look? the powerpack?
can new plugs go bad?