99 Volvo 5.0GL

[cobalt1999]

Carter P61122

 

[alldodge]

Walmart

Walmart will guarantee part

Marine for less

 

[Lou C]

If you have a carb the proper fuel pressure will be on the low end, the 3-8 psi spec you cited.
A 99 Volvo for sure won't have points, they used the Prestolite BID system on early models with electronic ignition and later they switched to the Delco EST IIRC.
You have an electric fuel pump, check the connections carefully, I think they are in the area where the raw water pump is (belt driven or in the crank pulley area?)

 

[Bhuie]

Ok,
So far the fuel line is clear from tank to engine. Fuel pump and filter have now been replaced. Same problem exists where full throttle is fine at start and then after a few seconds starts bogging down. Pull back on throttle and runs fine but top end is gone without bogging down and sputtering. So there are some electric components on the fuel filter and some type of large fuse like box you would see in a car fuse box. Wonder if it could be that or should I move to the holly carburetor? Coil?

 

[kenny nunez]

Try to unscrew the fuel suction pipe out of the tank. There is a fine mesh screen in the tube that may be partially plugged. Pitch the screen, put it back together then take the boat for a ride. Make sure all the fuel connections are tight and leak free.
You do not need a high pressure fuel pump with a carburetor.

 

[Bhuie]

Try to unscrew the fuel suction pipe out of the tank. There is a fine mesh screen in the tube that may be partially plugged. Pitch the screen, put it back together then take the boat for a ride. Make sure all the fuel connections are tight and leak free.
You do not need a high pressure fuel pump with a carburetor.

I have done all of that as well. All fuel lines are clean.

 

[Lou C]

You have a fuel pick up tube and an anti siphon valve. That’s the barbed fitting your fuel line attaches to. There is a spring loaded ball inside that valve. It’s there to shut off fuel flow if the fuel line between the tank & fuel pump leaks so you don’t get a bilge full of gasoline. Make sure that valve isn’t clogged and the ball moves freely. I have tested them with a vacuum pump and found that they open at about 1-2” Hg (inches of Mercury). Low pressure fuel pumps should develop about 9-10” Hg.
Fuel tank vent definitely not clogged?
Ever try running it on a separate outboard tank? That isolates the boat fuel system from the engine fuel system

 

[Lou C]

First pic shows the pick up tube & anti siphon valve second pic is testing them for vacuum leaks….
Vacuum leaks in the pick up tube, anti siphon valve or fuel line can cause this problem as can vacuum leaks at your fuel filter. If you run the boat on a seperate outboard tank you can isolate these factors..

 

[Bhuie]

View attachment 413266View attachment 413267
First pic shows the pick up tube & anti siphon valve second pic is testing them for vacuum leaks….
Vacuum leaks in the pick up tube, anti siphon valve or fuel line can cause this problem as can vacuum leaks at your fuel filter. If you run the boat on a seperate outboard tank you can isolate these factors..

Anti siphon ball has been removed. The fuel lines are clean from tank to carb. Fuel pump has been replaced. Fuel filter has been replaced.
It still does the exact same thing. Cold run full throttle then in less than like 30 seconds I loose top end power. She just starts sputtering. You can back off the throttle to scoot 3/4 and you can tell it’s trying to run right. Like a loose wire is twitching. I thought about replacing plugs and wires but at cold start she gets right up there then bogs. I have not pulled the carb yet.

 

[Lou C]

Did you pull out the fuel pick up tube and see if there's a clogged screen on the end of it? What can happen is this: some of these pick up tubes have a screen on the end and some don't (if you look closely at mine above you can see it doesn't have the screen). If you don't pull out the pick up tube you'll never know.

 

[Bhuie]

Did you pull out the fuel pick up tube and see if there's a clogged screen on the end of it? What can happen is this: some of these pick up tubes have a screen on the end and some don't (if you look closely at mine above you can see it doesn't have the screen). If you don't pull out the pick up tube you'll never know.

I did.
There’s a tube but no screen or anti siphon ball. I spoke with a mechanic and let him know what what was going on and he wondered if the fuel line in some area was loosing dexterity and squeezing off somewhere. I’m going to check that and replace the fuel lines. Since its inception I don’t think that has ever been done anyway. Next he suggested changing out the distributor cap and rotor. I’ll post back after those things have been done.

 

[99LarsonVP50]

Boat was running fine at the start of the season. I noticed a little dripping in the lower front of the engine suggesting a water pump needing to be replaced. Got the parts and replaced water pump. Getting to the three hex bolts I did turn the motor over several times to get to the hex bolts. I did this with both belts off and I’m now wondering if I affected the timing because now it is running rough. Runs fine at start up full throttle but then starts to bog and sputter out. Pull throttle back to 3-3500 rpm’s and you can feel the power go in and out. Almost like it’s not getting enough gas. Still runs but several times that same process repeats itself. Hatch was opened and it rained while working on it and wondered if water made its way in the carb. Wondering if Seafoam would cure it? So several possibilities going on here. Anyone here experience the same type thing going on?
Thanks,
Brad

I had this same issue when I bought my 99' larson with V.P. 5.0L GL. So the guy I bought the boat from told me the problem was intermittent. It would run all day on a hose with no issues. He made mention of adjusting trim seemed to help I attempted that when I was out on the lake but didn't seem to help me.
First time I took it out (hadn't gassed the boat up was on fumes) had no issues on the water but only ran it to like 2500-3k rpm for maybe 10-15mins. Put it back on the trailer.
Gassed it up a few days later and took it out on the lake ran great for about 30-40mins wife had to pee so went to turn around and head back to dock. Boat bogged down at anything over the same RPM range when I took it out the first time. I realized that if I kept the boat below 8MPH over ground would stay running so limped it back to the launch.
It seemed to me the ignition (spark) was failing not fuel. Trailered the boat home to check a few things out.
When I pulled the coil out I realized one of small wires coming from cap running to coil (closest to distributor) had at one point arc'd from the ignition wire post of connector to that wire. lets
What was happening was once coil/engine heated up it was arcing between the ignition wire connection and prong closest to distributor. Changed the coil and that one connector and full RPM range was obtained smooth and steady. There was also a pin hole through the center post where the ignition wire goes on the side with the prong it was arcing to.

 

[Bhuie]

Yes to the above. Fuel lines are Definitely clear.
I’m going to replace the distributor cap and rotor now to see if that changes anything.

 

[Bhuie]

I had this same issue when I bought my 99' larson with V.P. 5.0L GL. So the guy I bought the boat from told me the problem was intermittent. It would run all day on a hose with no issues. He made mention of adjusting trim seemed to help I attempted that when I was out on the lake but didn't seem to help me.
First time I took it out (hadn't gassed the boat up was on fumes) had no issues on the water but only ran it to like 2500-3k rpm for maybe 10-15mins. Put it back on the trailer.
Gassed it up a few days later and took it out on the lake ran great for about 30-40mins wife had to pee so went to turn around and head back to dock. Boat bogged down at anything over the same RPM range when I took it out the first time. I realized that if I kept the boat below 8MPH over ground would stay running so limped it back to the launch.
It seemed to me the ignition (spark) was failing not fuel. Trailered the boat home to check a few things out.
When I pulled the coil out I realized one of small wires coming from cap running to coil (closest to distributor) had at one point arc'd from the ignition wire post of connector to that wire. lets
What was happening was once coil/engine heated up it was arcing between the ignition wire connection and prong closest to distributor. Changed the coil and that one connector and full RPM range was obtained smooth and steady. There was also a pin hole through the center post where the ignition wire goes on the side with the prong it was arcing to.

Oh this is good stuff! I will definitely check this out!

 

[Bhuie]

Replaced distributor cap and rotor. No change. Moving to coil replacement. If this doesn’t fix I’ll pull the Holley carb and rebuild.

 

[Lou C]

How old is the fuel in the tank, straight gas or E10?
Reason why I ask is that last season, for the first time I had gas go bad on me. It was maybe 8 months old, stabilized 89 octane E10 which is what I have always used. Never had this before. BUT.....the only way I figured this out was to run the boat on a separate outboard style fuel tank with fresh gas. This was after replacing the points, condenser and cap, and rebuilding the Quadrajet. Still no improvment, so the only thing left was the fuel.
Lesson Learned: when you have a problem like this, check the fuel FIRST!
My gas cans were full with fuel for the yard engines/generator so I wound up getting a local guy to pump my tank out. Took all of 15 min. Worth it, one job I didn't have to do for a change!
Here's how I tested it, if you do this be careful with the fuel line hook up and use a shut off valve, just in case.

My old 4.3 4bbl just LOVED that Sunoco 94 Octane racing gas! Ran better than it has in a long time, got me thinking, maybe I'm better off draining the tank at the start of each season, so as to not waste time chasing a problem like this.

 

[Bhuie]

How old is the fuel in the tank, straight gas or E10?
Reason why I ask is that last season, for the first time I had gas go bad on me. It was maybe 8 months old, stabilized 89 octane E10 which is what I have always used. Never had this before. BUT.....the only way I figured this out was to run the boat on a separate outboard style fuel tank with fresh gas. This was after replacing the points, condenser and cap, and rebuilding the Quadrajet. Still no improvment, so the only thing left was the fuel.
Lesson Learned: when you have a problem like this, check the fuel FIRST!
My gas cans were full with fuel for the yard engines/generator so I wound up getting a local guy to pump my tank out. Took all of 15 min. Worth it, one job I didn't have to do for a change!
Here's how I tested it, if you do this be careful with the fuel line hook up and use a shut off valve, just in case.
View attachment 415802
My old 4.3 4bbl just LOVED that Sunoco 94 Octane racing gas! Ran better than it has in a long time, got me thinking, maybe I'm better off draining the tank at the start of each season, so as to not waste time chasing a problem like this.

I have thought about doing this very thing but the fuel lines from bottom of the tank to the carb are clear. I am 100% sure of it. And of course in any small engine or carbed engine of mine is NON-Ethanol only.

 

[Lou C]

The gas that gave me fits last season, was only 8/9 months old, stabilized E10 (all we can get at the gas docks here) and looked totally clear. It didn't BURN right though and other than smelling like varnish, or having obvious debris or water in it, there is no way you can tell that. In fact I just changed the fuel filter from last season and the inside totally clean, no debris or sign of water, etc. If all else fails, do what I did....
This was the first time this ever happened with this boat in 24 years, that's why I didn't suspect it at first, so I had gone through the carb and ignition before thinking it could be bad gas. Looks can be deceiving.

 

[Bhuie]

HEY GUYS…COIL FIXED IT!!!
Thank you all for the advice!!

 

[Lou C]

thanks for the follow up!
Just filled up my boat with Sunoco 94 octane for its trial run next week....