2008 5.0 GXi fuel pump replacement

[LattimerII]

My new to me 2008 Glastron GT 225 developed the infamous fuel pump whine at idle rpms on day 2 of owning it. No performance problems that I can tell. Just that irritating whine.

I replaced fuel filter today as that seemed like the cheapest possible fix. It may be slightly quieter, but it is still quite loud. My mechanic is going to check for anti siphon valve, boat side problems, etc. on Thursday. Assuming the problem can't be identified and remedied that way, I may try replacing the fuel pump myself.

Is there a thread or website detailing this procedure anywhere? I've searched and found lots of references to this problem but no instructions for swapping out the pump.

Thanks for any help.

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

It's very simple to change the high pressure fuel pump or the fuel pump assembly. The high pressure pump I swapped out actually came with installation instructions.

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

Yeah, it looks simple enough. I thought I read somewhere about making sure to depressurize the lines. I'm sure it's not hard, I just want to be sure I don't do it incorrectly.

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

I believe the instructions did say something about depressurizing first. Just a word of advice, replacing your fuel will not likely fix your problem, you need to find the root cause of why the pump has failed. Does your high pressure pump also get hot?

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

I believe the instructions did say something about depressurizing first. Just a word of advice, replacing your fuel will not likely fix your problem, you need to find the root cause of why the pump has failed. Does your high pressure pump also get hot?

Hot to touch. Yes.

Going to test a few things with the mechanic tomorrow. I'm hoping for a simple fix. I don't mind replacing the pump if that will fix it. I'm wondering if I got one of the pumps with the painted inside. No fun buying a new one, but at least then I'd have a reason and a fix for the problem.

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

I had the same symptoms of overheating and whining on my 5.0 GXi-E and I had a fuel pressure reading over 100 psi at the rail. I swapped the fuel pressure regulator from one engine to the other and brought the pressure down to 55psi and the overheating went away, there was also some crud on the screen of the regulator. I thought that I was fixed until I tried to go on plane, now I have backfiring and loss of power from the same engine. I now suspect the crud has clogged my injectors.

 

[Dave Dup]

Re: 2008 5.0 GXi fuel pump replacement

Check to make sure your vapor reservoir cooling hoses are clear. To do this disconnect the top hose coming off the reservoir from the exhaust riser connection nipple. Plug the nipple connection then start the engine and let the hose run into the bilge or extend it over board. If water is flowing from the hose the circulation around the reservoir cooling jacket is good. Let the engine idle for 30 minutes or more and check to see if the pump gets hot and the reservoir feels cool. If it gets hot and starts to whine after you reconnect it to the exhaust manifold you may have some back pressure from the riser cooling water system causing resistance to the reservoir circulating water system.
I'm placing my cooling line overboard thru a thru hull fitting and have not had any problems since.

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

I've already checked the cooling lines, I do not have a restriction.

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

Update:

Changed fuel filter the other day. Whine is still there but seems a little quieter. Still quite noticeable just somewhat quieter.

Took it to my mechanic today and he hooked up an external gas tank. Still whined after several minutes at idle. Says he could feel good flow through the cooling line to the pump, however it was quite hot. He doesn't believe the problem lies on the tank side of the system or the cooling line. He thinks its the pump itself. His advice was run it for now and replace in the winter unless it fails.

I'm seriously considering doing it myself. It looks really straightforward. Disconnect battery, disconnect all hoses/fittings, replace with new pump, and reconnect battery. Is that all there is to it, or am I missing something important?

 

[Redpony]

Re: 2008 5.0 GXi fuel pump replacement

The inlet to the high pressure pump has a mesh screen when you take the pump off, look to see if it is clogged with debris.

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

The inlet to the high pressure pump has a mesh screen when you take the pump off, look to see if it is clogged with debris.

Will do. New 2012 model pump without paint is ordered and on the way. Will be here next week.

From your response, it sounds like I'm right about just swapping them out?

 

[Dave Dup]

Re: 2008 5.0 GXi fuel pump replacement

Will do. New 2012 model pump without paint is ordered and on the way. Will be here next week.

From your response, it sounds like I'm right about just swapping them out?

Lattirmerll,
If your satisfied that all the pump screens and the fuel pressure regulator screen is clear. Then give this a try before you hook up your new pump: Disconnect the vapor reservoir cooling hose from the exhaust riser. Plug the exhaust riser connection, start the engine and let the cooling hose run disconnected into the bilge or extended it over board. Let it idle for a awhile and see if your pump whines or gets hot.

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

Lattirmerll,
If your satisfied that all the pump screens and the fuel pressure regulator screen is clear. Then give this a try before you hook up your new pump: Disconnect the vapor reservoir cooling hose from the exhaust riser. Plug the exhaust riser connection, start the engine and let the cooling hose run disconnected into the bilge or extended it over board. Let it idle for a awhile and see if your pump whines or gets hot.

I'm no mechanic, so you may have to explain things in a dumbed down version. Pictures might even be better!!

Anyway, I replaced the pump today. Was able to do it by matching connections from old pump, so that made it easy. I'm now 600 dollars poorer, and still have a whine . Still getting hot to touch as well.

How do I: 1. Check fuel pressure regulator ( I need to know where to find it for starters) and 2. Which lines are you talking about disconnecting and running overboard?

Edited to add: I work tomorrow, but can check things out a little more on Thursday (including breaking down old pump to look for paint)

Second edit:
Is this the line you are talking about leaving disconnected?

 

[tarheelgwb]

Re: 2008 5.0 GXi fuel pump replacement

I'm no mechanic, so you may have to explain things in a dumbed down version. Pictures might even be better!!

Anyway, I replaced the pump today. Was able to do it by matching connections from old pump, so that made it easy. I'm now 600 dollars poorer, and still have a whine . Still getting hot to touch as well.

How do I: 1. Check fuel pressure regulator ( I need to know where to find it for starters) and 2. Which lines are you talking about disconnecting and running overboard?

Edited to add: I work tomorrow, but can check things out a little more on Thursday (including breaking down old pump to look for paint)

Second edit:
Is this the line you are talking about leaving disconnected?

it looks like the hose youare holding is the water inlet hose from the thermostat? is that correct? i think Ddupille is referring to the exit hose from the fuel pump that goes to the exhaust riser to see if water flows thru the fuel pump smoothly. that hose is near the bottom of the fuel cell on the right side behind the high pressure pump. i hope this is correct.

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

The fuel pressure regulator is located on the fuel rail. Be careful when removing and installing the retaining clip, it's spring loaded and may pop off to be lost somewhere in the engine compartment. Schematic of a Volvo 5.0 GXi-E fuel system is shown in the link, item 23 is pressure regulator. There is a screen inside of it that you can visually inspect. Mine was clogged with some kind of material that could have been paint but there is no way to be sure.

http://www.volvopentastore.com/Fuel...on_id.373582659--store_id.366--view_id.787193

 

[Dave Dup]

Re: 2008 5.0 GXi fuel pump replacement

The hose you are holding is the inlet cooling hose. The outlet hose is one of two hoses on the top of the vapor reservoir tank; same diameter. The cooling hose is connected to the top side of the vpr tank. The one in the topcenter is connected to the intake manifold. You want the one that connects to the exhaust riser. This is the one you disconnect from the riser. Then plug off the riser connection. And let the cooling hose run into the bilge or extend it overboard and see if the pump whines or gets hot.

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

Thanks for the help guys. Plan for tomorrow is as follows:

1.Break down old fuel pump and inspect screens
2. If screens are clear, I doubt I'd need to check fuel pressure regulator. If they are clogged, then I'll proceed to check the fuel pressure regulator
3. Try Ddupille's solution
4. Cross my fingers

Will report back

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

Where did you find the pump assembly for $600?

 

[LattimerII]

Re: 2008 5.0 GXi fuel pump replacement

Where did you find the pump assembly for $600?

$635 on eBay from Marinepowerservice

Update for today:

I took off high pressure pump from old assembly. The screen appeared clean, so I did not even try and check fuel pressure regulator.

I disconnected the exhaust riser hose and tried to blow through it. I could blow through it, but there was some resistance and when I stopped blowing into it, a small rush of air exited back at me.

I did the next tests twice to confirm results. Water temperature at surface of lake today was 97-98 (it is pretty hot here right now).

I capped the exhaust riser hose and ran 6 feet of new hose from pump over the side of the boat. I then let the engine run at idle for 15 minutes. Using an IR thermometer aimed at the same spot on HP pump each time, I averaged 144 Fahrenheit with a one reading max of 148.

I worked on some other projects and let engine cool for an hour before reconnecting to exhaust riser hose. Within 3 minutes of startup, a slight whine was there with temp averaging 154 Fahrenheit. 6 minutes in and whine was very noticeable and temp hit 158.

Again I disconnected from exhaust riser and ran hose over the side. This time I did not wait any longer than it took to swap hoses. Temp was reading about 130 when I started this test. Quickly rose back to 144 but leveled out and stayed there. Ran for another 7-8 minutes without any climb in temp and no whine. An interesting note on this round of testing, I accidentally forgot to plug the exhaust riser hose before starting. Water poured from the hose into the bilge. What's interesting is that the flow from that hose was at least equal to if not greater than my hose run over the side and connected to fuel pump.

This leads me to the conclusion that at least part of the problem for some of us with the whine problem is overheating likely from too much back pressure in water cooling system. I think in my case Ddupille was right. I'll need to run the boat a little more to see if this fix continues to work. Now I just have to figure out how to make a thru hull fitting for this simple little "fix".

I'm happy that for now the whine seems to be gone, but dang this whole fuel cell design seems poorly thought out. Paint in some pumps, overheating, frequent pump replacements for many owners

 

[NoExcuses]

Re: 2008 5.0 GXi fuel pump replacement

144F still seems too hot, the fuel pump on my "good" engine only runs about 100F. After I changed the regulator on the "bad" engine, the temperature and pressure went to normal. I would still check fuel pressure on the rail and inspect the fuel pressure regulator. The regulator is as easy to remove/install as a fuel-water separator.