More fuel issues?

[CV16]

Ok, my dads boat has a Merc 228. It runs so sweet when you first take off in the mornings. When we shut down and fire up the kicker motor to fish, all seems well. Sometimes when we go to restart the main motor, it'll only idle. The fuel pump is good, 7-8lbs of pressure, as it should be. The fuel filter is full of gas, and I have changed the water seperator a good dozen or so times. We put an Edlebrock carb on it a few years back and it has always ran great. Well, yesterday, we did the usual 8-10 mile run out to where the fish are and it ran great. We fished til our limit was met, then headed in. It ran super all the way in. Then we decided to make a run out a few miles just to do it. On the way in, it sure felt like it was starved for gas as it would only barely run at idle again. The filter was again full of fuel, but the carb was dry. I say that the floats are getting stuck and want to rip in to it, my dad says it's vapor lock and not to mess with his carb. I need conformation from some people on here so my dad will agree to let me clean out the carb. We only have access to reformulated gas here, so I can imagine that the carb may be gunked up. He says it runs too good some times for the carb to need cleaning. And I do agree, it runs great, until you put on 15-20 miles. Am I on the right track? If not, please poiint me in the wright dirrection!!!

 

[CV16]

Re: More fuel issues?

PS, I have only heard of vapor lock. What the heck is it, and what are the symptoms?

 

[Another retired guy]

Re: More fuel issues?

PS, I have only heard of vapor lock. What the heck is it, and what are the symptoms?

Vapor lock occurs when heat build up causes the gas in the fuel line to vaporize before it reaches the carb. Used to be very common on cars back in the 50's and 60's ( I had such a car )
Cure was to wrap a cloth around the hot pipe and pour water onto it to cool it down!
In my case it used to stop the engine dead - wouldn't run at all, so don't think that's your problem.

 

[alldodge]

Re: More fuel issues?

I have changed the water seperator a good dozen or so times.

The filter was again full of fuel, but the carb was dry. !

Was the water seperator changed a dozen times this year, and if so why?
The filter was full (by removing and verifying I take it). How do you know the carb was empty (pumping the accelerator pump)?

 

[CV16]

Re: More fuel issues?

He has a clear fuel filter besides the water seperator is how I know the filter was full. There was no smell of gas and I could see no gas in the carb. No spray of fuel while pumping either. The thing is, I can let it sit for a day and it'll do the same thing, run sweet at first, then just get to where it'll only idle for a little bit, then nothing at all. Let it sit for a day or two, and all's well for close to a 10 mile run. I'm about ready to just buy him a different boat!!

 

[alldodge]

Re: More fuel issues?

He has a clear fuel filter besides the water seperator is how I know the filter was full. There was no smell of gas and I could see no gas in the carb. No spray of fuel while pumping either. The thing is, I can let it sit for a day and it'll do the same thing, run sweet at first, then just get to where it'll only idle for a little bit, then nothing at all. Let it sit for a day or two, and all's well for close to a 10 mile run. I'm about ready to just buy him a different boat!!

Might be drawing a vacuum on the fuel tank. May also be some issue with the two filters. How is the setup and routing of the fuel lines, through the two fuel filters to the carb? Can I also say that the clear fuel filter is an in-line filter like below?

http://www.summitracing.com/parts/knn-81-0261?seid=srese1&gclid=CNbPqbfSibkCFexDMgodqXwAvQ

 

[CV16]

Re: More fuel issues?

That is just like the filter he has. I believe the fuel line runs from the tank/pump/water seperator/in-line/carb. We had an issue with no gas in the past, that is why we put in the clear filter. That problem ended up getting solved by just taking apart eveery fitting and putting new thread sealer on them(Monster brand). It ran great with it this way most of last season. I also checked the vent in the tank, it's not blocked. I think I'm just going to wait until Wed, he's going to his cabin for a week, I can tear it apart without him stopping over and catching me, lol. I really think it's just the needles getting stuck closed. My problem is that he doesn't live too far from me and he stops over every time I seem to even look at his boat. HE thinks it is good enough, we can get out there and troll our way back in, no need to fix it. He has gained faith in the little 15hp Johnson we put on back!

 

[alldodge]

Re: More fuel issues?

The problem with the see thru filters is you can see fuel but it may not make it the rest of the way if it's not 90 to 100% full. Most setups have the fuel line to water seperator, to pump, to carb. With the clear filter being before the water seperator the water seperator may not be full. As you mentioned previously there could have been an air leak but using sealant probably fixed it.

You said the fuel pump is good at 7-8 psi but if that was last season, might just check it again. Something is restricting fuel or not suppling sufficient fuel

 

[CV16]

Re: More fuel issues?

The plastic filter is 99.99%full, there was 1 little bubble in it. I also just checked the fuel pressure todsay, right at 7 still. And you are right, the water seperator is before the pump. It is mounted right at the pump, I had to go check that out. I might just take a 1/2 day tonight(3rd shifter) and pull the carb then. I know my dad won't stop over at 3AM lol.

 

[alldodge]

Re: More fuel issues?

Sure looking like the carb. Look forward to hearing the results

 

[CV16]

Re: More fuel issues?

Ok, had the boat out a few times after cleaning the carb without dad knowing. I didn't see anything in there, but it sure runs good now! I powered out about 12-15 miles a few times to fish and had no issues what so ever. Well, one issue, didn't catch any fish! Dad was happy that I didn't waste my time tearing the carb down to clean it, ignorance is bliss! Now it's time to get on the Merc outboard section to try and figure out the wiring on my 1966 850! Got me a bass boat to put it on now!!!!

 

[alldodge]

Re: More fuel issues?

Sounds great, and now Dad can save his 15HP Johnson for fising or when he really needs it