1990 88 SPL Carb Draining

Hey all,

New to the forum. I have a 1976 Aquasport 170 with a 1990 Evinrude 88 SPL Outboard. I recently had awful phase separation issues in my below deck 27 gallon aluminum fuel tank. I believe it was a bad fill up from a local fuel dock. My tank, lines, filters, etc... are all brand new. I used my existing fuel line and primer bulb to manually drain the bottom of my tank. I endded up draining about 10 gallons until there was no more evidense of water or phase separation. The 3 pictures attached are when it was first discovered, after draining a few gallons, and after draining 10 gallons. My question is....does anyone know how to drain the carb bowls on this motor? Do i need to remove the carbs completely? The lowest screws I can find on the carbs are the plugs for the high speed jets. I am changing my fuel pump for good measure as well. Thanks!!

Those plugs will drain the carburetors.---------You just need to remove one of them on the upper carburetor and one on the bottom carburetor.

racerone said:

Those plugs will drain the carburetors.---------You just need to remove one of them on the upper carburetor and one on the bottom carburetor.

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Excellent!! Thank you for the response!

Brendanpd2 said:

1990 Evinrude 88 SPL Outboard. I recently had awful phase separation issues in my below deck 27 gallon aluminum fuel tank. I believe it was a bad fill up from a local fuel dock. My tank, lines, filters, etc... are all brand new.
....does anyone know how to drain the carb bowls on this motor? Do i need to remove the carbs completely? The lowest screws I can find on the carbs are the plugs for the high speed jets. I am changing my fuel pump for good measure as well. Thanks!!

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Wow, that's a nasty water infestation.
RacerOne is right, part #9 in the diagram is the screw to remove:
http://www.marineengine.com/parts/j...SLESA&manufacturer=Johnson&section=Carburetor

This wouldn't have helped in your situation, but I use Stabil Marine every time I add fuel to my boats. Ethanol fuel is just too flaky in a marine environment and the Stabil is pretty cheap insurance that you aren't introducing water into your fuel system.
https://www.goldeagle.com/product/sta-bil-360-marine

Unless you have reason to believe the fuel pump is bad I wouldn't bother replacing it. If you were having running issues before the water issue that's one thing, but good clean fuel should take care of any residual water in the pump.

KJ

That is realy bad fuel contamination.
I think I would drain the tank completely and put that down to a bad experience.
Dont take any chances with bad fuel, its good you have caught the problem now and not at sea a long way out.
avoid that fuel station like the plague. and tell everyone here it is.
they will soon clean out their crap tanks when people stop buying from them.
I always buy from a busy car gas station, the have much fresher fuel, never even 1 week old.

Thank you for the tips guys. Unfortunately I actually did find this issue while on the water. I got towed back to my slip twice. I have sense drained the fuel and started fresh. I changed the fuel pump because it has never been done and I want anted to upgrade to the newer omc version that is constructed to withstand ethanol fuels. Thank you were confirming those screws as the proper ones for draining the bowls. They worked well and I drained them until I was confident the carbs were full of good fuel. Today I ran the motor at idle for about 1/2 hour with a seafoam treatment. I wasn't able to take her for an actual test run. I performed a seafoam treatment before I knew about the water issue and had her running great for about a half hour in the harbor as a test run only to break down again and get towed....so I'm hoping now that I got all the water out this won't happen again. Wish me luck lol!!

I think if I was you I would potter around close to the shore for atleast an hour trying it at different speeds. you should be fine now, but this is
maybe me to think about a little kicker motor on the back for extra safety in the future.

hope I all goes well for ya.

Thank you for all of the input!! Update: I've had the motor running at idle on several occasions now after the new fuel, fuel pump, and spark plugs. Still haven't had a chance for a WOT test run. I've attached pictures of all 4 plugs after a total of about 30 minutes of idle and low rpm run time. Last one looks a little lean to me but I'm no expert. I seem to have a constant fuel slick in the water behind the motor but I cant find any leaks. Appears to all be coming from the exhaust. She seems to run a little rougher than I remember but I could just be imagining it with all the testing ive been doing. Hopefully will have a test run soon.

Time to do a compression test.-----Post your numbers.-----These motors have a nasty habit of breaking piston rings.

racerone said:

Time to do a compression test.-----Post your numbers.-----These motors have a nasty habit of breaking piston rings.

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Will do. I did one last year but I forget the numbers. I will post the numbers after completed. What about the spark plugs makes you think there could be a piston issue? Thanks.

fourth picture indicates that cylinder has problems.----But that is my opinion others will argue.