Fuel flow (primer bulb?) issue & low-oil alarm won't quit

[BMarkey]

I think I know what's up, but need some support.

My 115 Johnson (year 2000) ran fine three weeks ago. Today, it would stop running as if it were out of gas every few minutes. I noticed the primer bulb was not completely firm and pumped it, then the engine would run fine again. This happened on the trailer and on the water, consistently. No matter what, the primer bulb wold not stay hard.

First thing to replace is the bulb, right? It's relatively new, but I do see a slight crack (not all the way through).

If it's not that, then am I looking at a fuel pump? If not, what else? I removed and replaced the fuel-water separator (had a small amount of water in it).

At first, I feared a water problem again. I am still getting water atop my gas tank after rains and cleaning. But this definitely seems to be a fuel flow issue, right?

Simultaneously, my low-oil alarm sounded while on the trailer. I filled the tank with oil. But the alarm still sounds now every time I start the engine. I do not think the alarm sounds after the first time (engine start). I noticed the primer bulb from the oil tank was not firm and pumped it until it was firm. It stayed firm.

Also, the engine is making typical smoke and seems to be running fine, despite the oil alarm.

I suppose I need to check the oil alarm switch/sensor, wherever they are? Suggestions? Thanks.

[pmagrady]

If the new bulb does not solve the gas issue, check the spin on gas filter and the little gas filter on the motor. If that does not work, run the motor from a small external tank. That will tell you if you have a problem associated with the boat's tank, like a restriction in the vent.

Can't help you with the oil warning. I have Yamahas. The Yam alarm sounds each time you start. Some Johnson expert will chime in on this one.

[seahorse]

The low oil alarm is triggered by a float inside the oil tank. If it is sticking or shorted you will get a 10 second warning horn sound and the LOW OIL light will come on and stay on as long as the float is stuck or the electrical short remains. Disconnecting the oil tank wiring at the motor will tell you if there is a bad gauge or a bad float.

Any crack in a fuel component is an indication to replace that part.

Your fuel feed problem could be any number of things from the pump, pulse hose, fittings, restrictions, boat fuel system problems, etc. Each has to be checked out or substituted to find the problem(s).

[BMarkey]

Thanks, much, for the advice.

Here's the latest:

I replaced the Sierra fuel-water separator filter and the primer bulb. No effect.

The engine runs fine for a few minutes until the primer bulb starts to soften, then cuts out.

I need to know whether to look into the fuel pump (don't know anything about it, but it's 10 years old), and maybe whether to check for an obstruction in the fuel line or pickup tube in the tank. The fuel hoses appear tight and the fuel-water separator and fitting are tight. The hoses from the separator to engine are new. From the separator to tank, they are 10 years old. I do not notice any fuel leaking.

I do not have a fuel vent. The cap is vented.

I suppose I could re-hook up the 6-gallon tank and run directly from it. That would eliminate any problem with the boat fuel lines and separator. If all runs well from the small tank, then I must have a problem with the lines (or fuel pump), right? Is there any way I can eliminate the fuel pump as the source of the problem?

The low-oil alarm sounds after a couple of minutes and blares for at least 10 seconds, then shuts down. The low-oil light stays on. I would like to know more about checking the gauge and/or float/sensor in the tank. I just replaced the tank oil, so hope I somehow got that float stuck.

Isn't it odd that these two issues arose simultaneously?

I checked for kinked oil hose and checked the fittings. The tank is nearly full and the cap is tight. I see that there is a wire going to the top of the oil tank.

[njterrier]

As for the fuel pick-up on the sending unit on the tank, check to see if there is an obstruction. Also I would recommend cutting the bottom of the pick-up tube at a 45 degree angle. This would help the unit pick up fuel even if there is a small obstruction swashing around in your tank. Definitely sounds like a fuel starvation issue.

Two other questions.

1- What filter size (microns) is the sierra fuel/water filter?

2- What physical size is the actual canister?. Is it a short or long canister?

Hope this helps

Scott

[BIGDAWG2566]

SOUNDS LIKE YOU HAVE A BAD VRO PUMP

[BMarkey]

SOUNDS LIKE YOU HAVE A BAD VRO PUMP

VRO pump? How difficult is it to diagnose, replace? I have done carbs and an impeller.

The Sierra filter is the newer 2-micron version. Is has the short canister. It is new as of tonight.

The engine runs fine as long as the bulb is pumped every few minutes. he engine appears to be getting oil, as it is giving off its typical amount of smoke.

Edited June 28, 2010 by BMarkey

[BMarkey]

Update: I just hooked up a 6-gallon tank (premixed oil) directly to the engine, bypassing the fuel-water separator. I pumped the new Quicksilver primer bulb until it was firm and the engine started right up and ran well.

After around five minutes, the low-oil alarm sounded for around 10-20 seconds and then stopped. The "no-oil" light was solid on the console. I suppose the engine was getting double oil because I did not disconnect the oil injection tank.

A minute or two later, the primer bulb slowly had gone soft (did not collapse) and the engine slowly died from fuel starvation.

These are the exact same symptoms experienced when the engine ran from the internal tank.

So ... It's not a restriction, tank, or fuel hose (new, rated for E-10) problem, right?

What's next? VRO pump?

From what I understand, the VRO is a fuel pump and oil injection system in one, located on a bracket between the carbs at the front of the engine. They are reportedly expensive to replace (how much)?

If that's my problem, how does the engine run at all? Does this pump just die or does it fade out? Can it be rebuilt?

Am I getting the oil alarm because the pump is not properly mixing oil and gas, or is detecting a lower than required flow of gas?

How difficult a job is this? Is there a how-to available anywhere?

Any advice?

Thanks.

[BMarkey]

I've been pricing a new VRO pump locally and on the 'Net. It's going to cost me $400 to $439, it appears. Also, they are difficult to find in stock. The non-oil mix pumps are almost as expensive.

[Sunbury]

If you've got the usual amount of smoke and the engine hasn't slung a piston through the side yet I would guess it's probably more of a sensor issue than a pump issue. Either way its probably a good investment to let a qualified mechanic look at it. Has the oil level in the tank gone down any or have you run it enough to tell?