5.0 FL loss of Power/RPM at WOT

[mwagne30]

O.K. Crew, its been years since my last Post and I'm back to the folks that know.

I'm in a spot, bad, 11 kid's under the age of 15(no, Not all Mine) looking to tube this week and were not running right....

1996 Four Winns 5.0 FL/ SX Outdrive will run great till I get her up to the higher range of RPM?

She will run strong, right up to almost 4200RPM and fall back to 3800 stutter and die if I don't throttle back. She will fire right back up and idle like nothing happened, and run right back up to 3800 and hold it but once I break that its like she is choking out.
Never ever had an Issus running up to 51/5300 RPM in the past and to date, first issue ever!

Part of me thinks fuel, pump, feed, other part thinks coil/electrical??

All Gages read normal, and I'm at a total loss,
*Filled boat and truck at the same time, same pump, truck runs fine, Check
*Added Sea foam like I always do, even gave the old tow vehicle Got a shot of the good stuff. Check
*Changed water/fuel separator- no change, Check
*Have can of electrical connection cleaner, going to spray cap and rotor to make sure we are clean and dry next.TBD

Asked one of the local Marina's, and you have to love this, $25.00 per question,(time is Money) just bring it in for a diagnose $125.00 (Experience is Priceless) Don't you love it...

Please share some wisdom, I would love nothing more then to smile at the Owner.......

and A BIG thanks to all that assist

 

[Scott Danforth]

What was the contents of the fuel filter when you inspected it?

what is your fuel pressure

BTW, its never the coil

 

[alldodge]

Finding the FL is a carb motor. Appears your running out of gas, but only thing missing is it should start to back fire from running lean. Agree check fuel pressure. Can get a vacuum fuel pump tester for under $20. Make up a Tee fitting using rubber fuel line and place between pump and carb

Pressure should be 3 to 7 psi

Can also be antisiphon valve on the tank. Can run the boat from a 5 gallon gas can by placing fuel line in the can.

 

[jimmbo]

Engine is leaning out. Plugged filter/water separator is common cause. But I have experienced the same problem and this is what I found...
I will assume you have a Holley 2bbl, I believe the power circuit is restricted with gum/dirt. Remove the metering block, remove the power valve and clean all the passages in the block. It wouldn’t hurt to clean the passages in the carb body either. Reassemble and give it a try

 

[mwagne30]

OK crew, Ill get to work today.
Start with the easy, look inside the fuel water separator.
Next, fuel line in the gas can trick, carb cleaning.
after that, I will check to see if I can gather a Holley gasket kit, a few cans of carb cleaner, fuel line, clamps and a gage.
Ill keep everyone updated.

Thanks for everything as always!

Folks I was never on a boat until just a few years ago, let alone operated/worked/owned one
Today, I cant even imagine life without one!
Thanks again!

 

[mwagne30]

I just posting an update

Issue ended up being the fuel filter in the Carb. I guess going from a 20 micron to a 10 Micron water/fuel separator was not in my best interest.

Anyhow once I was informed that it had a filter in the carb, (I guess its called a stone) I removed it, had to search for the Spring for about 10 Min, replaced everything and we were up and running.
FYI also replace the water/Fuel separator and went back with the 20

 

[Lou C]

surprised that changing from a 20 micron to a 10 would have that effect.
been using Sierra 10 micron filters for years. Gas is always very clean when I dump out a sample.

 

[alldodge]

The stone was the issue, not the 10 micron
Good to hear your up and going

 

[mwagne30]

Ok, same issue, she will run right up to 39/4100 RPM and falls right back on her nose, if I come back on the throttle, she perks right back up. If I lean back in the throttle back on her nose.
I can operate all day on anything below 3800RPM.but the second I break the 3900 mark its all over.

I just cant believe its the carb, but please give me your thoughts.

 

[alldodge]

Ok, same issue, she will run right up to 39/4100 RPM and falls right back on her nose, if I come back on the throttle, she perks right back up. If I lean back in the throttle back on her nose.
I can operate all day on anything below 3800RPM.but the second I break the 3900 mark its all over.

Thought you were good, but In this case I don't think its the carb, it would be low fuel supply.
The carb is not getting enough fuel. Check fuel pump pressure

 

[mwagne30]

Ok crew, let me bring everyone up to speed
Sit back and open a cold one of your choice

Fuel pick up Removed and replaced, still nosed off at 4100

Back flow valve replaced, same issue

check pressure on fuel pump, good to go- pass on replacing

Rebuilt carb, same issue

Break down and take her to the Marina that wanted to stick it in my back over the forth, the owner takes the boat out for a ride (To See for himself What its doing) I get it, and were out on the water just about to break into that Hold on to your hat mode and she falls on her face. he stops looks under the dash, unplugs the tach, he hammers it down with the tach UN-plugged in and she runs awesome, as a matter of fact never better, he plugs the tach back in and all is well???

he goes on to tell me that its about the 10th Four winns he has seen with the dash/Tack issue , and tell's me next time it acts up unplug run for 30 seconds, plug it back in and enjoy

has anyone ever had this happen?????
BTW he charged me $250.00 for 15 Min of review!

 

[alldodge]

Yes, but in most cases there are also comments about the tach bouncing around every so often. Time to get another tach

 

[mwagne30]

Its not that easy, the whole dash is one unit. no longer in use. does anyone know of a repair center?

 

[Lou C]

Ahh the silly VDO panel. Don’t know what they were thinking! Head over to
www.ifourwinns.com
I think if you search you may find how others put in a new panel . Might take some fab work.
BTW the old Medallion Gauges in my 30 year old H200 still work...