SwedeSpeed - Volvo Performance Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
247 Posts
Discussion Starter #1
Hi, I had posted this on the other forum.
What I am trying to find out is if there is any reason to believe that this method of fuel removal from the tank could damage the fuel pump in any way?




"I am writing this to share my experience in removing my old "covid" fuel from my backup XC90, 2004 2.5T which has been sitting a lot; also with an eye to using this method to get gas to run my generator in an emergency if I run out of propane. This is not a DIY, and I am not promoting this method, but just sharing my experience and method for removing fuel from the XC90.

I had tried the standard method of siphoning with no luck and also looked into the "GasTapper" method, using a stiffer 1/2" OD hose with a small flexible hose threaded through it. Unfortunately, this method also does not work on the XC90.

What worked for me was to purchase a Schrader Valve Extender Hose like for a dually tire to fit onto the Schrader Valve on the fuel rail, I think also there is a Schrader Valve by the fuel filter, but I did not try that location.
Anyway, I removed the valving from the male end of the extension and fitted a piece of fuel hose to the threaded end there with some RTV on the threads and a worm clamp to hold it.

Next, after bleeding the residual pressure from the Schrader Valve on the rail, I threaded the female end of the extender onto the rail Schrader valve.

Next, I used a fuel line clamp on the fuel hose drain line and clamped it closed in order to build starting pressure when the pump primes in Pos.2. Then checked for leaks.

Next, I started the XC90, then released the clamp from the fuel line drain and it began pumping fuel into my gas can. It flows at a decent rate at idle and doesn't seem to affect idle speed or engine smoothness, it ran as normal.

This method seems to work well, but I haven't ran it by VIDA yet, wondering if it will set a code for pressure. I'll look into that soon. There were a lot of options for the Schrader Valve Extender, keeping in mind that the angled, all metal ones could have an interference issue on my other XC, I opted for a rubber hose one, here."
 

·
Registered
Joined
·
454 Posts
Sounds like you wanted to do this so your engine wouldn't ingest the old stale fuel, but this method requires the engine to ingest the old stale fuel?
 

·
Registered
Joined
·
247 Posts
Discussion Starter #3
Sounds like you wanted to do this so your engine wouldn't ingest the old stale fuel, but this method requires the engine to ingest the old stale fuel?
No, I did this so that I wouldn't have to run out all of the old fuel from the tank before I refilled with real gas prior to my emissions inspection and anticipated low fuel use as I no longer commute. This way yes, I did run at idle for a couple of minutes, but that's it. Seemed better than driving more than a hundred miles or physically disturbing the pump and associated wiring. Feel me?
Also, as stated, I wanted to use this method to provide ancillary fuel for my generator if I go through my propane during an outage.

Any thoughts on my "question"?
 

·
Registered
Joined
·
1,954 Posts
Duplicate
 

·
Registered
Joined
·
1,954 Posts
I wonder if unplugging the fuel line at the filter and turn the key to pos 2 to “prime” the fuel? Never done this myself. Just a thought.

I don’t think this would damage the pump unless you ran it bone dry for a period of time.
 

·
Registered
Joined
·
436 Posts
I wonder if unplugging the fuel line at the filter and turn the key to pos 2 to “prime” the fuel? Never done this myself. Just a thought.

I don’t think this would damage the pump unless you ran it bone dry for a period of time.
I like this idea too.
 

·
Premium Member
Joined
·
637 Posts
I wonder if unplugging the fuel line at the filter and turn the key to pos 2 to “prime” the fuel? Never done this myself. Just a thought.

I don’t think this would damage the pump unless you ran it bone dry for a period of time.
I remember when fuel injection first arrived in 1970. We learned that the fuel pump would run for a second or two the stop when starting so that fuel would not run all over if there was a leak.There is likely some kind of flow-limiting logic in the event fuel pressure is too low or the engine isn't running on these even more clever later models. Could get ugly in the case of an accident with the key left on and a fuel line cut. Gravity drainage is bad enough!
You could simply hot-wire the pump, though?
 

·
Registered
Joined
·
1,954 Posts
good point on the fuel leakage.
 

·
Registered
Joined
·
247 Posts
Discussion Starter #9
I wonder if unplugging the fuel line at the filter and turn the key to pos 2 to “prime” the fuel? Never done this myself. Just a thought.

I don’t think this would damage the pump unless you ran it bone dry for a period of time.
Yes, I thought of using the priming mechanism to drain the fuel, but the fuel doesn't continue to flow after the prime and that would take a lot of key turning to remove a quantity of fuel. I think also that in the event of an accident, that power to the fuel pump is cut by impact sensors. this is why the vacuum pump is necessary to properly run brakes in the event the engine is shut off in an accident.

I haven't looked yet with VIDA at what the pump is doing when I'm draining the fuel. I assume that it's working harder to maintain the rail pressure, so I don't open the clamp full bore, but it still pumps a good quantity in a short time with the engine running. I would hesitate to run it for a long time because I imagine the pump is running as if the gas pedal is floored when performing this operation.
 
1 - 9 of 9 Posts
Top