help with mercruiser 5.0L !

[alldodge]

Re: help with mercruiser 5.0L !

I replaced the separator. Filled it to the top with gas. Installed it and cranked her over. She didn't start. I pulled the separator again, and a little bit of the gas was gone. I THINK the manual fuel pump is doing its job, but I don't know if it's building adequate pressure.

I also cleaned the coil wire and cleaned the inside of the coil itself. It was goopy and full of grease. I am not sure if this is how they come from the factory. But that crap was everywhere. I pulled the wire from the coil side and left it sitting on top of the coil, and cranked her over. I didn't see a single spark, nor did I hearing any pop pop. MAYBE it's a spark issue after all, but I am still perplexed. I will have the new coil tomorrow.

slothman I do believe you have two issues and one is compounding the other. You may have fixed the fuel issue by replacing the filter, time will tell.

The next is spark and goop or grease should not be found. Your coil has cracked and the oil inside is leaking out and needs replacing. Once you get the coil replaced we may be able to determine what other issues are lurking and figure them out.

Like dad use to say, we all got to hang in their like a hair in a biscut

 

[slothman]

Re: help with mercruiser 5.0L !

i lied, it is fuel. I poored some gas down the carbs. She started right up. Idled on the muffs for about 60 seconds, then died, just like she did on the lake. should i just order the damn fuel pump ???

 

[alldodge]

Re: help with mercruiser 5.0L !

i lied, it is fuel. I poored some gas down the carbs. She started right up. Idled on the muffs for about 60 seconds, then died, just like she did on the lake. should i just order the damn fuel pump ???

Take the fuel pump off and pump it by hand to see if you can get sucktion on the inlet port. Look at the pump arm and see if it is damaged. If you get sucktion and the pump arm is not damaged, reinstall the pump. Then get a gas can and put your fuel line going to the tank in the can.

 

[slothman]

Re: help with mercruiser 5.0L !

Take the fuel pump off and pump it by hand to see if you can get sucktion on the inlet port. Look at the pump arm and see if it is damaged. If you get sucktion and the pump arm is not damaged, reinstall the pump. Then get a gas can and put your fuel line going to the tank in the can.

I will inspect fuel pump and fuel line for blockage

 

[achris]

Re: help with mercruiser 5.0L !

I'm not convinced you have a mechanical pump. We need an ENGINE serial number... Provide that and we'll be able to give you better info. My gut says it's an electric pump and your problem is the oil pressure switch.

Chris...

 

[slothman]

Re: help with mercruiser 5.0L !

I'm not convinced you have a mechanical pump. We need an ENGINE serial number... Provide that and we'll be able to give you better info. My gut says it's an electric pump and your problem is the oil pressure switch.

Chris...

the pump is mechanical. My serial number is 0F593121 . I already looked up the fuel pump part number and got one ordered. I'm also going to blow out the fuel lines.

 

[slothman]

Re: help with mercruiser 5.0L !

replaced the spark plugs today and DAMN they were nasty ! You can tell they haven't been replaced in a while lol. Fuel pump should be in friday so I should update soon ....

 

[achris]

Re: help with mercruiser 5.0L !

I'm not convinced you have a mechanical pump. We need an ENGINE serial number... Provide that and we'll be able to give you better info. My gut says it's an electric pump and your problem is the oil pressure switch.

Chris...

the pump is mechanical. My serial number is 0F593121 . ....

Thanks... Don't know what planet I was on, you already gave the serial number much earlier... Thanks anyway...

Chris......

 

[slothman]

Re: help with mercruiser 5.0L !

Thanks... Don't know what planet I was on, you already gave the serial number much earlier... Thanks anyway...

Chris......

not a prob !

 

[slothman]

Re: help with mercruiser 5.0L !

Still not getting fuel to the carb. New fuel pump, still won't start until I fill the carb myself. Swapped the anti siphon valve and still nothing. What's next? Fuel pickup tube? When I pull the tank/water separator line nothing comes out. Not a drop of fuel. Hose looks good.

 

[achris]

Re: help with mercruiser 5.0L !

Get a separate fuel container, preferably something like an outboard remote tank, and hook that directly to the engine.... At least that will tell you if you have an engine problem or a supply problem....

Chris....

 

[NHGuy]

Re: help with mercruiser 5.0L !

Well if you have a new pump and no fuel coming up there's every chance that the problem is before the pump. You can repeatedly change the fuel water separator or...
Get some fuel line, get extra. Maybe get a barb without the anti siphon in it, and empty that tank all the way to the bottom. If you have enough line you can siphon it out. Alternately you can get some clear plastic line and run it in the sender hole or onto the pickup. Only issue with using the tank fuel pickup is that if there's a lot of debris the pickup will clog before the tank is empty.
Pull the fuel sender and look in there, get the interior of your tank really perfectly clean. Can't say that loud enough! Before re rigging, put the fuel cap on and apply air pressure to the line or the pickup point to blow any crap out of the vent. Or for the cost of a length of vent hose just replace the hose and blow out the fitting while it's open. Then clean up the anti siphon valve, put it back on and use the new line to the pump. That's what I did, best afternoon I ever spent. Don't skip the anti siphon valve, it's for your safety. A good pump will pull clear fuel through that thing forever.
I think that's your best move.
Since your plugs and other stuff are so bad why not finish it off with wires, cap and rotor. Probably will be worth it.
The day I drove off after doing fuel and ignition was the happiest I have been in a long time. The boat I had been mucking with just pulled away. Felt like it would tow an ocean liner compared to how it had been.

 

[alldodge]

Re: help with mercruiser 5.0L !

If it doesn't start using the remote tank, recheck your pump installation. Did the pump arm get beside the rod actuator?

 

[slothman]

Re: help with mercruiser 5.0L !

If it doesn't start using the remote tank, recheck your pump installation. Did the pump arm get beside the rod actuator?

no, I made sure the rod was sitting on the right spot on the pump arm.

 

[slothman]

Re: help with mercruiser 5.0L !

Get a separate fuel container, preferably something like an outboard remote tank, and hook that directly to the engine.... At least that will tell you if you have an engine problem or a supply problem....

Chris....

Yep I'm going to stick that damn hose in a gas can

 

[slothman]

Re: help with mercruiser 5.0L !

dedicated gas can didn't work either. I think fuel the lines have air and the pump isn't primed. I'm deleting the water separator just in case the top passages are gunked up .

 

[slothman]

Re: help with mercruiser 5.0L !

ok deleted the water separator, fuel pump is pumping REAL good now. I know it's getting gas up to the carb. However I am not sure if the carb is clogged. Could the coil possibly be bad? I checked the primary resistance, shows 1.0-1.2 . secondary shows 10,900 . spark plugs were black...possibly indicating unburnt fuel. what is the next step ? I think I have ruled out the tank. It's pulling straight from the tank and tons of fuel is flowing up to the carb like it should.

 

[Fun Times]

Re: help with mercruiser 5.0L !

I'm deleting the water separator just in case the top passages are gunked up .

ok deleted the water separator, fuel pump is pumping REAL good now. I know it's getting gas up to the carb. However I am not sure if the carb is clogged.

So do you plan on trying to clean the fuel filter/water separator base assembly and installing a new filter? or just remove it all together?

With the carburetor flame arrestor removed, ignition key off, try opening the throttle all the way while looking to see if any fuel flows down into the intake manifold.

spark plugs were black...possibly indicating unburnt fuel. what is the next step ?

Did you clean or install new spark plugs? If they are fouled, the engine may not start.

 

[NHGuy]

Re: help with mercruiser 5.0L !

So throw a tablespoon of fuel in the carb throat and see if it kicks. If it does start cleaning the carb.

 

[slothman]

Re: help with mercruiser 5.0L !

So do you plan on trying to clean the fuel filter/water separator base assembly and installing a new filter? or just remove it all together?

With the carburetor flame arrestor removed, ignition key off, try opening the throttle all the way while looking to see if any fuel flows down into the intake manifold.

Did you clean or install new spark plugs? If they are fouled, the engine may not start.

I removed the entire water separator system. It pumps WAY more gas now, and has zero restriction. When I pump the throttle I can see gas squirting in. I can turn it over, it will start, and then die 10 seconds later. Almost like it is out of fuel. HOWEVER...I replaced the spark plugs and they looked nasty and black. Just like unburnt fuel. I went ahead and ordered a new coil for $39. But....I have a feeling the carb is going to need an inspection. maybe a plugged jet or something else ???