No fuel in float bowl

[Garage Dog]

So..I take my boat to "Rip Off A-Rama Marine Repair" here in town. I'll save the gory details but I'm not taking it back. The check engine light is on and the motor will not stay running. It's a 2000 Johnson 90 PLSSE.
I figure it's time to resurrect my old 2 stroke skills of 40 (really...? 40 years) ago. Built lots of road race engines and a few dirt bike motors but no outboards.

Anyway I removed all 4 carbs and none of them have fuel in the float bowls! They are bone dry except a slight bit fuel dampness around the brass screw in the float bowl. I've never seen anything like that before. Is this something new or are my carbs just that far out of adjustment? I can't imagine this is normal.

I have a Johnson shop manual which is a help but I am not sure if float drop is measured with or without the gasket. Any other tips you can offer are greatly appreciated!

 

[gm280]

Well it sound like your fuel pump needs looked at. Remove the fuel line from the pump and crank over the engine. If fuel comes out in a nice stream, then you have something blocking the fuel at the carbs. I can't see four carbs all being bad and not allowing any fuel in. The odds of that are truly amazing to say the least. JMHO!

 

[Chris1956]

Check Engine alarm is a fuel restriction. Check fuel filters for clogs, check antisiphon valve for clog. Check main strainer for clog.

 

[Garage Dog]

Thanks for the feedback.
I had already checked for restrictions and clogged strainers. I don't have a anti siphon valve. I did as GM280 suggested and disconnected the fuel line between the pump and fuel rail. fuel would flow when the ball was squeezed but WOULD NOT flow when turning the key.

Doing some research I found that I can get a VRO replacement pump that pumps only fuel for around $140.00 which is cheeper than a VRO rebuild kit and I mix my fuel anyway. Have any of you guys gone this route before? The pump # is 8402-460

http://parts.promarineusa.com/productdetail/M50/1/1/8402-460​

 

[Fed]

Yet the pump pulls enough vacuum to bring on the check engine light?
I'd investigate further.

 

[Garage Dog]

Yet the pump pulls enough vacuum to bring on the check engine light?
I'd investigate further.

Where would you suggest? If pumping the ball freely flows fuel with the hose removed it seems to indicate there are no obstructions between the tank and where fuel enters the motor. I have checked the fuel lines to make sure they have not delaminated like the old ones that were on the boat when I bought it. They are only a few months old and look new inside. I guess the only other component would be the carbs themselves. Any other ideas?

 

[Fed]

I'd establish if it is indeed the vacuum switch bringing on the check engine light and where it is in the fuel circuit.
I'd guess it would be right before the fuel pump but I'm not familiar with your motor.

Did you check the filter beside the separator mounted on the motor?

 

[oldboat1]

blind lead for me too (haven't played with that motor). See references here to primer pumps, and whether to keep key depressed during starting (or not) -- just thinking maybe it's your starting procedure. But just cranking the engine should operate the fuel pump. Let's see, did you run the fuel out of the carbs when shutting it down, then discover in restarting that fuel isn't being supplied? (The shop might have run them dry, if that was the prior use.) Hard to figure. Got an owner's manual?

 

[Tim Frank]

Use a vacuum gauge to check fuel line suction and a pressure gauge to measure output. Just taking off the fuel line to see if fuel pulses from the hose does not really tell you anything.
That test was designed by the same guy who gave us the "ground-a-plug-on-the-block to verify spark quality" test.

Will the bulb fill the carb bowls?

You said you removed all 4 carbs on a 90HP ? .... I hate to ask, but are you sure you counted correctly?

 

[gm280]

Tim, I think there are two carbs per side. If you look at the break down of his engine they list two for port and two for starboard. JMHO!

 

[Tim Frank]

Tim, I think there are two carbs per side. If you look at the break down of his engine they list two for port and two for starboard. JMHO!

Well if you think there are 4, obviously I'm wrong.
I thought it was a 2000 vintage 90 HP, V-4, with a carb for port side and a carb for starboard side....the typical OMC setup.

 

[Garage Dog]

[QUOTE=Tim Frank;n1006403


Will the bulb fill the carb bowls?
No

.... I hate to ask, but are you sure you counted correctly?
Yes, it's a 60 degree V4



I do have a manual and I found a trouble shooting section with the symptoms I am having but nothing on no fuel in the float bowls. There is quite a bit of stuff to check. I hope to have a chance to check some of these things out this weekend...stay tuned!

 

[Chris1956]

Tim, Those 60* V4 motors have a two throat throttle body for each bank of cylinders. Two assemblies containing a float chamber bolt to the throttle bodies. Neither the throttle body or the assemblies contains all the parts of a traditional carb. So it is fair to say the motor has two 2 barrel carbs, or just as fair to say it has 4 carbs.

FWIW - You need to buy 4 carb kits to rebuild the carbs on that motor.

Dog - Did you check the condition of the vapor separator and pump?

 

[Tim Frank]

]

Will the bulb fill the carb bowls?

No

Surely that implies a simple fuel line problem.
Per Chris's earlier post, check for reversed bulb, or various blockages.

 

[Faztbullet]

fuel would flow when the ball was squeezed but WOULD NOT flow when turning the key.

An it wont with a VRO pump as it has to build up enough vacuum to overcome the air motor spring. That why when its running you hear a click every minute or so ,that click is when pump pulses fuel. Fill the bowls manually so engine will run and then pull the line from pump to carbs and see if it pumps,if not VRO is bad or major air leak/blockage

 

[Garage Dog]

An it wont with a VRO pump as it has to build up enough vacuum to overcome the air motor spring. That why when its running you hear a click every minute or so ,that click is when pump pulses fuel. Fill the bowls manually so engine will run and then pull the line from pump to carbs and see if it pumps,if not VRO is bad or major air leak/blockage

This sounds like a good place to start! HOPEFULLY I'll have a chance to work on it this weekend.

I have eliminated things like the squeeze ball being backwards and any blockages in the tank all the way to the fuel pump itself per suggestions from all you guys. One thing I haven't looked at yet is the pulser that tells the pump to pump. I understand that they sometimes get stick thus will not actuate the fuel pump.

Regarding testing with a vacuum gauge, I still have one from years ago..haven't seen or used it in years. It measures vacuum as well as fuel pressure. Might have to watch a few you tubes to remember how to use it!

 

[Tim Frank]

If you have an OEM manual, it will have a diagram of the gauge hook-up, and the suction and discharge specs.

 

[Fed]

Checked the BRP website, motor doesn't have a vacuum switch.