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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
If you already got most of the fuel out of the tank, you can loosen the tank mounts and remove the rear bolt then jack the back end of the tank up so the remaining gas goes forward.
Add: You probably want to replace the pump.. The fuel flows through the electric motor past the armature / brushes..
Last edited by Max Headflow; Mar 8, 2025 at 05:10 PM.
If you already got most of the fuel out of the tank, you can loosen the tank mounts and remove the rear bolt then jack the back end of the tank up so the remaining gas goes forward.
Add: You probably want to replace the pump.. The fuel flows through the electric motor past the armature / brushes..
I thought about that Max but was thinking of raising the rear end up, replacing the tank quick disconnecing valve with a fitting that I could connect a hose to, drop the tank back down and let gravity do the rest but I don't know the thread size of the tank valve. I have a quick disconnect setup for the tank cross over (copied the way Gary/FSG did his) so it would take all of 15 minutes to pull the tank and I am in no rush but I might try your tip first if I can get the damn hose to stay put.
I am replacing everything, pump, filter, regulator, quick disconnect tank valve and top plate gasket. After seeing the deteriorated sock, I am not so sure I want to replace that part. Would you?
You found your problem. The exit hose disconnected from the coupling.. That connection should be on real tight.. Now what may have done it was the decaying pickup sock.. The routing is sock, pump, filter, regulator.. If the filter plugs, the pump is going max pressure.
Do you put additives in the tank? Stale ethanol gas will do it..
If you're talking about the sock that's there to protect the fuel pump.. absolutely replace it..
After taking a closer look I realized that screen should be replaced; I had to think about the how the fuel gets through the system and realized the screen was the pick up point; I just didn't think about it. What causes the screen to deteroriate like in the picture I posted? Ethanol? I wonder when it came apart and if pieces of the screen could have clogged up the pump? As it stands now, I don't know what caused the failure.
You found your problem. The exit hose disconnected from the coupling.. That connection should be on real tight.. Now what may have done it was the decaying pickup sock.. The routing is sock, pump, filter, regulator.. If the filter plugs, the pump is going max pressure.
Do you put additives in the tank? Stale ethanol gas will do it..
I started thinking about the fuel flow and realized, as you point out, that the sock is the pickup point and has to be replaced. I just never thought about it, I was happy that the pump assembly came out easier than I expected.
How could the exit hose disconnect? IIRC, there is no clamp at that connection so I thought I might have disonnected it by pulling on the pump assembly to cut that hose at the filter but I also thought that connection should be tight enough that I could not pull the hose off.
The only additive I add to the fuel is Star Tron or Stabil; every so often I run some MMO through. I don't know how long it takes for ethanol fuel to go stale with a stabilizing additive. The gas in the tank was from a fillup in September last year with the appropriate amount of Star Tron added.
If the filter plugs and the pump goes to max pressure; could that cause the pump to fail? If pump is at max pressure could that push the exit hose off the connector? I still don't know what caused the failure.
There isn't any clamp but the hose is pretty stiff. Its possible that the stabilizer did something to the hose maybe not. Either way I've not been able to pull on off the bottom valve. It's stuck on pretty good.. In fact bet you have issues pushing the hose on to the fittings. I use a heat gun and get hose real hot.
The pump design will limit the pressure.. The pump is like the water pump in an old outboard. It has a ton of fingers.. I'd bet once the pressure gets to a certain point it stops building. Cut the old one apart.
The fact that you go 0 fuel pressure says that something popped loose. Even a plugged pump or filter would generate some pressure. The fact that you had none and gas dribbles out of the connector says a hose popped off or filter / regulator assembly popped apart.
Update #5
Well, aside from the deteriorated sock I know why the fuel pressure was zero; the exit line separted before the connection at the quick disonnect valve.
I started to drain the tank as Max suggested but the handle bars prevented the tank from being raised back to front so I pulled the tank back and raised front to back and was able to siphon all but a few ounces; put the tank back in place and removed the quick disconnect. I still can't figure out how/why the exit line broke where it did; I think this is unusual.
Everything back together, replaced every thing. The regulator that came in the Fuel Pump Factory kit was a bitch to push in. Waiting for the new exit line/quick disconnect assembly to put all back together.
Question: Removing the system from the tank requires straightening out "leg" with the filter. If installing with that leg straightened out, how do you retract the leg back into the correct position. Maybe it will be obvious when I install but if there is a trick; those of you who have done this, let me know.
I also found an unknown rubber item rolling around in the fuel tank.
Update #5
the exit line separted before the connection at the quick disonnect valve.
put the tank back in place and removed the quick disconnect. I still can't figure out how/why the exit line broke where it did; I think this is unusual.
Everything back together, replaced every thing. The regulator that came in the Fuel Pump Factory kit was a bitch to push in. Waiting for the new exit line/quick disconnect assembly to put all back together.
I also found an unknown rubber item rolling around in the fuel tank.
First thought is age and getting brittle for the line snapping off
Have see a rubber grommet thing on the bottom of the pump then the sock
Serves give the pump something to set on as well a noise damper.
Hope the rest goes easy WP
Last edited by djl; Mar 9, 2025 at 05:40 PM.
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