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rodm717

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I have a '76 Evinrude 85hp v4 that I've been very happy with. New coils, wires, plugs, and fuel pump, working great for two years. Last trip out 2 weeks ago and has ran great until this morning. I could not get it start and also could not get my kicker to start. First time.
I swapped fuel tanks and disconnected/reconnected multiple times and checked the choke and actuated the throttle linkage. Nothing. Full battery, just topped off last night.
I'm going to check spark, voltage,and compression. I bought a new fuel tank and fittings to eliminate that, but also want pass the fuel through a filter while transferring the new fuel into the new tank to a new tank just in case s I'mome water got in the fuel. I'm thinking it has to be fuel or electrical.
Any other ideas or experience with these older v4's would be appreciated. I have read the starters can sometimes pose a problem by not producing the full amount of voltage and intend to check that. The starter looks older, if not original.
I ordered and will have some diagnostic tools in
the next couple of days to help.
Horrible to have this happen at height of crabbing in the Chesapeake Bay in Maryland. Realistically only 6-8 weeks left.
 
Okay, I have spark on all 4 cylinders and compression is 125psi across all 4 cylinders. So far so good. But when I pulled the plugs , I noticed one was fouled and black while the others were fairly decent. More importantly, I am not smelling gas after after dry firing while compression testing. I pulled the new looking fuel pump cover, gas coming out until I pulled hose, and the screen looks clean and gas is freshly mixed non-ethanol. I generally try to only run non-ethanol.
Next steps are to clean or replace plugs, remove air box to spray a little starter fluid directly into carbs, and measure voltage off of coils. Going from running fine to nothing is starting make me think there is an issue with fuel flow more than anything. Possibly the pump. Only 2 years old, but.....
Any thoughts or other ideas are appreciated.
 
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Also, running fine to nothing, I'm finding it hard to think it is the carburators, but not counting that out. Pulling the line to the carbs from the pump should tell me something. Ran out of light, but hope to get back to it tomorrow.
 
I would drain the carbs & see if clean fuel (pre-mixed obviously) or a water cocktail comes out.
Obviously it's highly unlikely both motors broke down simultaneously.
 
Droid thanks for response. I am further into it now. Motor starts on starter fluid. I have fuel in front of and behind fuel pump to carburators. No fuel came out when I open either carburator bowl plugs on each carb.
I'm guessing something is wrong with float, or needle valve or a serious blockage in both carbs.
I would have hoped only using non-ethanol would have prevented gumming and blockage.
Next step is to check tee and hope it is there, otherwise I'm going to be into carburator rebuilds.
 
Tee was clear and ended up running to my local BRP/Evinrude/Johnson parts dealer about an hour away. It did cost more than online, but I have them it in my hand today, not 5 days from now and know I have the right OEM parts.
I purchased (2) 439076 carb rebuild kits, (2) 386573 silencer to carb gaskets, and (1) 319796 silencer cover gasket. Again could have got this online for about $40-50 less, but like the idea of supporting my local brick and mortar. I ended up spending about $140.
Reading literature and watching videos tonight, pulling and rebuilding carbs tomorrow. Still need to pick up gasket sealant, 5/16" fuel hose, and 1/4" evap hose for crank case to silencer.
I will probably pick up a brass tee to replace the plastic one as well.
I'm honestly think back pressure from the resting/expanding fuel in the tank and pressure in lines finish off the float valve pin and or seat, or the floats gave way. Will see tomorrow I guess what is there tomorrow. Happy this is pretty much the last ancillary part on the motor to be replaced. Golden coating is still on the nuts and look unmolested. Crazy to think these carbs may be completely original to this 50 year old beast.
The old gentleman and marine mechanic in the shop also said that Evinrude was dumb in the sense that these have some of thickest sleeves in the cylinder bores ever made. Why they are referred to as bullet proof. And over the years they used the same sleeves bored and thinned for higher horsepower models. Not sure if that's true, but sounds like a good story to me. 😂
 
Okay, I see now there was nothing on any of the gaskets surfaces when I pulled apart.
Unfortunately I have not found a smoking gun. Except for the bowls being bone dry. Everything is really clean and great shape. I did notice some cracking on the fuel hoses, but I pulling and yanking could have caused that. Regardless they definitely needed replaced.
Out to get some more carb cleaner and fuel hose and then rebuild and get back on. Hoping beyond I get this all sorted and running by end of day. Fingers crossed.
 
1st trip out on the Chesapeake Bay and.motor settled in perfectly. Very crisp and responsive and idle did settle out., compared to initial start up.
Only thing left to install is the new silencer cover gasket and need to modify a bit. There are dovetails for alignment around the perimeter that are a little tight. I need to use a razor and "pinch" the inside edges of the dovetail, then it should fit fine. I previously ran without this gasket and not sure what, it any, improvement it will actually make. Regardless the engine will be completely OEM. At this point all periferal systems will be upgraded within past 2-3 years. The starter and high speed coils on the stator are the only things original to my knowledge.
 
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