No Go Juice to Injectors

[The T Man]

I have a 350 Mercruiser Alpha I Bravo I and I need some help. I have a boat in Maine and I need to get it out of the water soon. I live 150 miles away so my trouble shooting comes at an expense (one weekend = one try). Here is the situation.

I am not getting fuel. The motor stalled - starved for fuel. I checked the fuel filter / water separator and it was only about half full. I checked the line and filter prior to this and everything was clear. I could blow through the line and hear bubbling in the tank. I could suck on the line and got fuel quite easily. Even though I could hear the fuel pump run (pulse on with the ignition on), I figured that this must be the problem. I replaced the pump but still have the exact same issue. The water separator is dry.

I really would appreciate any advice on this and thanks.http://forums.iboats.com/images/smilies/confused.gif

 

[Fun Times]

Re: No Go Juice to Injectors

I have a 350 Mercruiser Alpha I Bravo I and I need some help. I have a boat in Maine and I need to get it out of the water soon. I live 150 miles away so my trouble shooting comes at an expense (one weekend = one try). Here is the situation.

I am not getting fuel. The motor stalled - starved for fuel. I checked the fuel filter / water separator and it was only about half full. I checked the line and filter prior to this and everything was clear. I could blow through the line and hear bubbling in the tank. I could suck on the line and got fuel quite easily. Even though I could hear the fuel pump run (pulse on with the ignition on), I figured that this must be the problem. I replaced the pump but still have the exact same issue. The water separator is dry.

I really would appreciate any advice on this and thanks.http://forums.iboats.com/images/smilies/confused.gif

Hi, Sorry But with this info that I highlighted it's a little hard to understand what engine you really do have because you said you have a 350 Mercruiser Alpha I Bravo I and I need some help. The alpha is a stern drive & the bravo is a different style stern drive, And with each stern drive you could have any size and style engine from a carb to MPI, And not knowing the year is kind of hard to know what we are working with also. When you say Injectors that to me would be a MPI engine, But with out knowing what engine you have it's still a guess.


As a starting point if you really do have a 350 mag MPI engine, You will want to start with checking the fuel pressure on the fuel rail on top of the engine their is a schrader valve with a black cap you will need to unscrew, That is where you would hook up the fuel gauge like what is in this link.http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=92699. Normaly you would want to see a fuel pressure of anywhere from 36ish psi up to 43ish psi. Good luck to you with it.

 

[havasuboatman]

Re: No Go Juice to Injectors

You need to fill up your waterseparater/fuel filter all the way to the top and try it again.

 

[The T Man]

Re: No Go Juice to Injectors

The motor is a 1999 EFI 350 Mag Mercruiser Horizon. I believe it it a Bravo I stern drive and I thought that the Alpha I referred to the motor type.

Havasuboatman, Do you really think that by me dumping out the remaining fuel when I checked the water separator, could be the issue here? When I first removed the separator, I saw that it was about half full (optimistic I dumped the remainder because of possible H2O and contam. Do you think this could be it? I only had enough battery to give it about 30 seconds of cranking before panic began to set in. I did re-look inside of the separator and I didn't see much fuel there so I figured I replaced the fuel pump for nothing.

 

[havasuboatman]

Re: No Go Juice to Injectors

I am almost certain that is your problem.

 

[Fun Times]

Re: No Go Juice to Injectors

I am almost certain that is your problem.

I also agree, You do need the fuel filter full to start the engine a lot easier and to get a good idea of whats going on, When the filter was half full you may have had a air pocket anywhere between the filter and the injectors, Sometimes to release the air pocket you can push the schrader valve while the fuel pump is on, Just have some rags in the area covering the valve all around.

 

[The T Man]

Re: No Go Juice to Injectors

Thanks very much. I will head up to Maine this weekend armed with a cup of fuel and a battery charger. I will report my results as soon as I can. Thanks again for your help.

http://forums.iboats.com/images/smilies/biggrin.gif

 

[45Auto]

Re: No Go Juice to Injectors

I only had enough battery to give it about 30 seconds of cranking

First thing you need to do is get a fully charged battery in it.

If that doesn't fix it, don't be surprised if the empty water separator isn't your problem.

I change the water separator every year on my MPI motor, NEVER have filled the new one with fuel before installing it, and the motor has always fired back up within a second or two of turning the key after I've changed it.

Have you checked to see if it's getting spark? Verify that before you keep fooling with the fuel system.

If it is getting spark, sounds like you need to download the Mercruiser Factory Manual #24 from the "adults Only" section and start the EFI "engine cranks but will not run" diagnostics starting on page 5G-30.

 

[The T Man]

Re: No Go Juice to Injectors

I was wondering if there was some type of valve in the system to release any trapped air. Where is the Schrader valve located on this motor, "push the schrader valve" and what does it look like, a tire style valve?

 

[Fun Times]

Re: No Go Juice to Injectors

I was wondering if there was some type of valve in the system to release any trapped air. Where is the Schrader valve located on this motor, "push the schrader valve" and what does it look like, a tire style valve?[/QUOTE]Yes, Kind of like A tire valve.

 

[The T Man]

Re: No Go Juice to Injectors

Do you know where these are typically placed? Is it on the fuel rail?

Thanks.

 

[havasuboatman]

Re: No Go Juice to Injectors

If you engine has a schader valve it'll be on the fuel rail, probably under a black screw on cap.

 

[uaw9fan]

Re: No Go Juice to Injectors

Instead of filling the water seperator with gas, I always use an old outboard primer bulb with some fuel line on the outlet.
Remove fuel line and put primer bulb inline and squeeze away. Once the system is full, start the motor and let it run for a minute. then turn the motor off and hold a rag around the fitting while you remove the primer and return it to normal.

 

[The T Man]

Re: No Go Juice to Injectors

Thanks for everyone's help! After a foiled attempt last weekend (40+ MPH winds) I made it to the mooring and utilized everyone's advice. I filled the F-Filter with gas and gave her a crank. It started! Only to stall after one minute. Second attempt - same thing. I figured that it wasn't the air bleed valve as the injectors would accomplish the same thing. I finally figured that the problem was on the up side (filter to the tank) because the pump was giving sufficient pressure to the injectors. It was just not getting fuel to the injectors. I was fooled by blowing air from the filter back into the tank and hearing bubbles, ASSUMING that the line was clear. Well I have a "check valve" (one way valve) in line and this malfunctioned so it was NOT opening when the power was applied but it somewhat closed and provided restriction to the fuel's flow. I took it out of the circuit and voila! It started and stayed running. Problem solved and before the snow started to fly. THANKS again for everyone's help.