5.0L EFI Question

[Rickochet]

Engine is a 2001 5.0L EFI Bravo II. If the electronic fuel pump is bad does the ECM sense this and not send pulse to injectors? Engine getting spark in plugs but no fuel to throttle body and node lights show no pulse. Engine has a new battery.

 

[alldodge]

Could use a serial number

The ECM normally doesn't know if the pump is working unless your boat has smartcraft and then its a maybe because of your year. Does the tach show around 300 rpm when cranking? Are your getting two beeps when key is turned ON and hear the fuel pump run?

 

[Rickochet]

Ser. # 0M069225 I have MMC controls. The only beep I can hear is the MMC beep at the controller 40' from the engine. The person at the motor didn't feel any activity at the pump when key turned on. Also took the fuel line off at throttle body and got no fuel flow when key turned on. It is highly probable the pump is seized from long storage. Also seems like maybe another issue with no pulse from ECM. I didn't pay attention to the tach, but the person at the motor said it seemed to be turning over just fine with the new battery.

 

[harleyman1975]

If you have power to the pump when cranking and no fuel I would make the assumption that the pump is kaput.

 

[alldodge]

Thanks for the SN - I'm seeing MEFI-3, TBI, TB-V ignition

You should be able to put a table spoon of gas down the throttle body and it should fire. If it does then we know its fuel, which it should be from your noid light test.

Still wonder if the tach is showing anything while cranking?

 

[Rickochet]

Thanks for the SN - I'm seeing MEFI-3, TBI, TB-V ignition

You should be able to put a table spoon of gas down the throttle body and it should fire. If it does then we know its fuel, which it should be from your noid light test.

Still wonder if the tach is showing anything while cranking?

It will start with starting fluid sprayed in throttle body. Will it fire with starting fluid even if the ECM does not show signal to the noid light?

 

[alldodge]

It will start with starting fluid sprayed in throttle body. Will it fire with starting fluid even if the ECM does not show signal to the noid light?

Yes it will hit with starting fluid but that is bad stuff to use in a motor, to much can break things, so don't use much.

If the ECM is not turning on the injectors there is no fuel. You should see the noid light flash IF the ECM is turning them on. Just trying to make sure its either fuel or spark were missing right now.

 

[Rickochet]

Yes it will hit with starting fluid but that is bad stuff to use in a motor, to much can break things, so don't use much. If the ECM is not turning on the injectors there is no fuel. You should see the noid light flash IF the ECM is turning them on. Just trying to make sure its either fuel or spark were missing right now.

Used just enough fluid to see if it would fire. Going to fix the fuel from the pump issue first then go after the electrical next. I am guessing that there is an ignition module that sends a signal to the ECM. The ECM in turn sends it to the injectors. So, maybe bad ignition module? How do you test for that?

 

[alldodge]

So I take it, it didn't fire and you think its spark?

 

[Rickochet]

So I take it, it didn't fire and you think its spark?

You have me confused. There is spark, pulse and signal. Spark plugs are getting "spark" since they fire with starting fluid.

 

[alldodge]

You have me confused. There is spark, pulse and signal. Spark plugs are getting "spark" since they fire with starting fluid.

OK, but this is why I asked the question

Used just enough fluid to see if it would fire. Going to fix the fuel from the pump issue first then go after the electrical next.

This tells me your going to fix a fuel problem but then go to electrical, so could not conclude it was fuel or electric

I am guessing that there is an ignition module that sends a signal to the ECM. The ECM in turn sends it to the injectors. So, maybe bad ignition module? How do you test for that?

The ignition module does send signal from module to ECM, and the ECM supplies pulses to the injectors. No need to test the module because if it was not working the motor would have no spark.

Need to check fuel pressure, and the Green and Blue wires on the injectors are the ones the ECM applies a ground to fire the injectors. Both will have a Pink wire which should have 12V

 

[Rickochet]

The ignition module does send signal from module to ECM, and the ECM supplies pulses to the injectors. No need to test the module because if it was not working the motor would have no spark.

Need to check fuel pressure, and the Green and Blue wires on the injectors are the ones the ECM applies a ground to fire the injectors. Both will have a Pink wire which should have 12V

Will check this weekend. Thanks for your help.

 

[Rickochet]

My bud, the marina mechanic has concluded that the fuel pump is bad. Getting 12v and does not do anything when key is turned on. He informed me this weekend that about his attempt to order a new one through the local Merc dealer. First, according to the dealer, Merc will only sell the pump with the cooler. Second, is that they are on backorder until the end of the month. I am seeing after market pumps everywhere with price ranges all over the board.

My question is why does Merc sell pump and cooler only? Are they fixing a design flaw in the original unit? Also, are the after market pumps bad juju?

 

[alldodge]

You can still get just the pump and I would just get it. There were concerns with the coolers corroding and leaking fuel, mainly with boats in salt water.

Is the fuel pump relay energizing when key is turned ON for 2 to 3 seconds?

 

[Rickochet]

You can still get just the pump and I would just get it. There were concerns with the coolers corroding and leaking fuel, mainly with boats in salt water.

Is the fuel pump relay energizing when key is turned ON for 2 to 3 seconds?

He told me he disconnected the pump plug and it was getting 12v. I am finding no OEM pumps without the cooler. So, will go with an aftermarket one.

 

[alldodge]

Merc doesn't make the pump so aftermarket is fine. If you search on 861156A1 several come up

 

[Rickochet]

Merc doesn't make the pump so aftermarket is fine. If you search on 861156A1 several come up

I did a search using that number and they are everywhere. Ended up ordering one from Amazon since I get free 2 day shipping. Now to get that puppy installed. There is room to get down next to it in the houseboat hull but still looks like a royal PITA to get out since it is located so close to the stringer and mount. I have read it is "easiest" to remove all the hoses and nuts, screws and slide the whole pump/cooler assembly out the front. I will have a fresh box of band aids ready.

Has someone here actually taken one of these off? Besides the two water lines, fuel lines and power plug are there a few key nuts or screws that hold it in place? What actually holds this in place to the engine? Here is a diagram.

https://www.perfprotech.com/mercury-...0?umodel=12340

 

[Rickochet]

Ok, update. Actually, the problem was with twin engines. I posted it as one to simplify things. My bud the mechanic replaced the fuel pumps on both motors. Both getting fuel to the manifold but neither getting pulse to the injectors. How odd is it for ECM's on both motors to be bad? The mechanic's boat is two slips away from mine and he had a lightening strike a few weeks ago that blew his battery chargers. My boat is aluminum hull. Any chance it could have fried both of my ECM's? So I guess I need to get the ECM's checked. Can these be checked taken off of the motors at a Merc dealer with the proper equipment? The local dealer will not do on water service.

 

[alldodge]

Actually, the problem was with twin engines.

Its always best to know the whole story and not just part of it.

Both motors were running fine until after a lighting strike, and now both motors will not start?

 

[Rickochet]

Its always best to know the whole story and not just part of it.
Both motors were running fine until after a lighting strike, and now both motors will not start?

Boat has not been started in years. Ran fine when last started. New fuel, new fuel filters, new impellers, new batteries. Generator runs fine. Engines crank fine. No impulse to noid lights. I am not blaming the lightening, just mentioned it to see if this have ever happened to anyone else. Engine #0M069225 and 0M069236. You identified these earlier as having the TBI ignition. Do these use the same ECU as the Delco systems?