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1990 60hp evinrude losing power or shutting off at mid throttle

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shanej

Member
Hello everyone, I'm new to the forum .This is my first post.I'm at my wits end with my engine.First let me say that I'm somewhat of a mechanic.Not an expert but I have experience working on all kinds of engines. With that being said, here is my dilemma. My 1990 evinrude 60hp vro will start just fine, idles fine, and will put around in the water all day long. Now , when I get halfway through the throttle range it struggles a minute then cuts off. Then I turn the key to start it and it fires right up and will run the same way as earlier mentioned. Now sometimes in this process it will run like nothing is wrong but it for sure will act up most of the day. I have it hooked to a clean, plastic 6 gallon tank with fresh fuel and stabil added to the gas. The vent cap is open. The primer hand bulb is brand new and the hose as well. The plugs are new and per manufacturer's specs.The carbs are clean and just rebuilt. First run on these rebuilt carbs. ( By the way, the boat was doing this prior to all of the new hoses and bulbs and Carb rebuilds ). The fuel filter I installed is a glass see through so I can quickly identify a clogged filter but that is clean. The only hoses I haven't replaced YET are the factory fuel hoses on the motor. I don't know how old they are but I did check to insure the didn't have any holes in them to let air in the fuel line and the don't. My assumption is one of two things. It is either a collapsing fuel line that shuts when the engine starts demanding fuel at the higher Rome. Then opens back up when the motor shuts off, allowing the engine to start immediately after and idle fine or its the fuel pump. The bad thing is I don't know for sure what bad fuel pumps symptoms are and a new fuel pump is 400.00 ! Any input from someone who has experienced these symptoms? Please and thanks.
 
If a fuel restriction exists, the fuel primer bulb would have a tendency to be drawn flat.

If pumping the fuel primer bulb (acting as a manual fuel pump) solves the problem, suspect a failing fuel pump. THose pumps can be rebuilt with kits.

If pumping the fuel primer bulb results in no difference, I would suspect that the brass high speed jets, which are located in the bottom center portion of the craburetor float chambers, are still somewhat fouled. Clean them with a piece of single strand steel wire.... carburetor solvent just doesn't do a proper job of cleaning those jets.

Hint... Long drawn out paragraphs are hard to read as they have a tendency to flow together.
 
Tried pumping the bulb while engine was bogging. Didn't help. When I rebuilt the carbs I did run a small glasses screwdriver through the jets you refer to. Do you think the underhood factory hoses might be collapsing? But even so, when I'm squeezing the bulb they should open and the engine should gain its power back. Right?
 
In all my many years in the trade, I"ve never seen a fuel line collapse. However, should one have a tendency to collapse, it would have to be on the suction side of the pump, between the pump and the fuel supply.

The cause of the problem you describe is normally/usually due to a Sticking Timer Base under the flywheel, Clogged High Speed Jets, or having the Throttle Butterflies opening too soon if the link/sync has been tinkered with.
 
How could I confirm a sticking timer base? Thanks for your time. Is the base something that can be viewed while the engine is running?
 
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shanej said:
How could I confirm a sticking timer base? Thanks for your time. Is the base something that can be viewed while the engine is running?
Click to expand...

Have engine Not running. Spin prop to align shifter dogs and put engine into forward gear. Have someone slowly advance the throttle while you observe the timer base under the flwheel. I should move smoothly from its normal retard idle position up to the full spark advance position.
 
Thanks Joe...ill check it out and ill check high speed jets again just to be sure.you've been very knowledgeable. Thanks again:)
 
Run with carburetor cover removed and observe amount of fuel coming up each main jet when it acts up.--------Use a strong flashlight for this simple test.----My bet is dirt just above the float valve , restricting fuel flow to one carburetor.--------A thorough cleaning job and replacement of all hoses should take care of it.--------------Does the waterpump indicater hose come of the top of the block or is it still installed on the side ( exhaust cover ) , service bulletin says it must be on the top of the block.
 
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Looked all over the evinrude parts website, didn't find a rebuild kit for the vro fuel pumps but I did find a rebuild kit at a website called www.maxrules.com . It is 135.00 .beats paying 435.00 for a new one. Still not convinced that the fuel pump is the problem because when I squeeze the primer bulb as the engine starts bogging down it doesn't make the engine pick back up so ill check the timing base like joe recomends and the carbs like racerone said and see what happens. That will be this weekend. Will keep you all posted on the results. Thanks everyone
 
shop.evinrude.com----------Look under outboard accesories -------fuel systems.-----------------It is all there mate.
 
Racerone asked about the water outlet hose in an earier thread. Do the symptoms my engine is doing suggest overheating ? Because it ran fine for 20 minutes or so when I first left the dock that day after I rebuilt carbs and installed new primer bulb.
 
"...starts fine...idles fine...mid throttle...ran fine for 20 minutes..."
What do you guys think about SLOW mode? The 1990 model has a rev limiter powerpack.
 
Service bulletin came out in 1994 to move the tell tale hose to the top of the block-------------18 years ago !!------Has the motor never been in a knowledgeable shop ???---Has the waterpump impeller been replaced within the last 5 years ???
 
I'm not sure of the history of this engine. See my boat originally had a 1990 50hp evinrude that acted the same way that this engine is doing. Then thinking it was a 450.00 fuel pump problem a friend of mine at work sold me this 1989 evinrude 60 hp engine of his tree fallen pontoon boat for two hundred dollars . This engine ran ok last summer and now here I am again with same problem as the 50. Who know.....maybe its ethinol.???
 
I think at this point I'm going to take all the carbs back apart, ensure they are thoroughly clean, then take vro pump apart to check for anything out of the ordinary, clean it if necessary install another new fuel filter. Then I'm going to buy 5 gallons of ethinol free gas and run it.if runs with no problems then I'm going to switch tanks to ethinol and if engine acts up again that will be the tale tale of this ethinol crap ....... what do you guys think?
 
Do you guys think it could be the powerpack? Because all this trouble started last summer when I would be in full throttle the engine would just shut off for a second and then cut back on, sort of like u cut the key off real quick. Then it just progressively got worse from just a quick shut off to running full throttle and then instead of skipping off it would just shut off. What's y'all opinion? Does that sound like something a powerpack would do? The fuel system is sparkling clean and carbs look great ......????
 
Well anyway..I got some ethanol free gas.gonna give a go in the water tomorrow. Ran great on the hose.I will keep y'all posted.
 
Wiring looks good.....tried ethano free gas, still bogs out just after Quaternary throttle. Fuel pump is my next order. Does anyone know what " slow mode " is?
 
When some motors are overheating they go into " SLOW " mode.----------------Ignition starts to operate erratically to prevent engine damage.-----------Speed -------Limiting --------Overheat --------Warning ---Hence the term -----SLOW.-------In 1990 the 60 HP had that system.-------Have you moved the tell tale hose to the top of the block ?? Or does that not seem like a reasonable thing to do ??
 
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I bought the engine used . The water pump indicated hose comes off the side of the engine. Is this the hose your talking bout moving and if so what do in need to do? Thanks for your help.
 
Yes and the service bulletin came out on that modification, in 1994 to prevent possible overheat on those motors.------It should have been done long , long ago.-----Talk to your friendly dealer to have it done !!
 
Another quick question guys...I'm going to move the water line on the engine like the service recall says but do I have to put new thermostat and new cooling switch sensors and all that to. Or just simply relocate the water line and see if the problem is remedied?
 
Well, move the telltail water hose and it still stalls around quarter throttle but if I throttle up very slowly sometimes it makes it to wot. Going to bite the bullet and buy an overpriced fuel pump. Don't know what else it could possibly be. Tried new gas tank,new fuel filter,new primer bulb and hose, rebuilt all carbs, new plugs,and a lot of trips to the Marina.
 
If the thermostat is sticking would it hurt any thing to take it out completely? Don't understand why an outboard has a thermostat anyway. Cool water is constantly being pushed through from the waterpump. Why stop the flow with a thermostat? This engine also has a temperature switch. Maybe that's bad.
 
shanej said:
If the thermostat is sticking would it hurt any thing to take it out completely? Don't understand why an outboard has a thermostat anyway. Cool water is constantly being pushed through from the waterpump. Why stop the flow with a thermostat? This engine also has a temperature switch. Maybe that's bad.
Click to expand...

(Thermostat Purpose)
(J. Reeves)

Many engines are considered high performance engines and demand a thermostat(s), and many smaller hp engines also require a thermostat for the following reason. The pistons actually distort/twist off round when running. The thermostat is required to keep the outer wall surrounding the steel cylinder, and the cylinder wall itself at a temperture to compensate for the distortion.

With the thermostat removed, the difference in temperture between the inside the cylinder and the water jacket quickly reaches a point whereas (in effect) you have a oblong piston running up and down a round cylinder, or vice versa. Bottom line is without the thermostat, the piston and cylinder wall could be damaged in a short period of time.

The thermostat in your car isn't there simply to have the heater function properly..... think about it.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay auction at:

http://shop.ebay.com/Joe_OMC32/m.html?_dmd=1&_ipg=50&_sop=12&_rdc=1
 
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