[rkporsley]

When the ignition is turned to On (not Start), as you noted, the pump runs for a second or two. That should prime the system, although it might take two or three cycles to really see how high it will go. Running the engine is a good idea, but if that won't work, at least the line should be primed and there's a good idea of whether or not it's reaching the right pressure. Also, once the pump stops running, the pressure should hold; if it drops rapidly, that could again indicate the cap is leaking, or there's a problem elsewhere.

Note: the fuel pressure gauge is connected into the fuel delivery line using a "T" (usually at the fuel filter connection) so that the fuel rails and fuel pressure regulator downstream of the filter are all in the system during testing.

Thanks, I'll get a fuel pressure tester from an auto shop and see what the result is. If it is low or not holding pressure, are there other things I should do before replacing the assembly with the cracked cap?

 

[berto]

I'm tempted to just buy a whole new assembly for $340 (in stock here in Anchorage). I can't be without a car for work next week. Already missed some this week and had to work out rides today. If the cap is cracked and that was the issue before, I don't see why something else would cause the issue this time.

@rkporsley I am also located in Anchorage. It may be the solder/weld job on the cap done by A&A failed, or the o-ring is damaged. I have a new fuel pump cap and the o-ring for an H6 in my garage if you want to try installing them.

 

[rkporsley]

@rkporsley I am also located in Anchorage. It may be the solder/weld job on the cap done by A&A failed, or the o-ring is damaged. I have a new fuel pump cap and the o-ring for an H6 in my garage if you want to try installing them.

Thanks! I'll post the results when I can.

 

[1 Lucky Texan]

Amazon sells a Dorman-branded kit that looks just like that NAPA one, cheaper too.

 

[plain OM]

If it is low or not holding pressure, are there other things I should do before replacing the assembly with the cracked cap?

Perhaps, with the tester "T" adapter in the fuel supply line at the filter, after a few cycles of the pump, see if the pressure reaches the spec. If ti does, then crimp the rubber hose after "T" adapter. If the pressure doesn't drop, the problem is downstream, i.e., it could be a leaking injector or failed pressure regulator, both of which could affect starting. If the pressure still drops as before, then the cause is upstream of the "T" adapter, meaning the pump or leaking line from the pump, although in the latter case fumes would be a giveaway. But the first thing will be to see if the pump does build up pressure when priming.

 

[gen2lover]

What are the chances there's an H6 car in a salvage yard near you.
I just bought a pump from an 04 H6 for $30
No cracks in the anodized cap whatsoever
Worth a try

 

[berto]

What are the chances there's an H6 car in a salvage yard near you.
I just bought a pump from an 04 H6 for $30
No cracks in the anodized cap whatsoever
Worth a try

I will answer this because I am also located in Anchorage. I am constantly watching local cl and FB marketplace for H6 parts cars, or H6 cars in good condition at a fair price. They are rare. There are two subaru salvage yards within 50 miles of town, and both "know what they have", and charge relatively high prices for much of their inventory. So, unfortunately, locally finding a used H6 fuel pump for a fair price is unlikely.

 

[gen2lover]

I will answer this because I am also located in Anchorage. I am constantly watching local cl and FB marketplace for H6 parts cars, or H6 cars in good condition at a fair price. They are rare. There are two subaru salvage yards within 50 miles of town, and both "know what they have", and charge relatively high prices for much of their inventory. So, unfortunately, locally finding a used H6 fuel pump for a fair price is unlikely.

That's a shame

 

[rkporsley]

I will answer this because I am also located in Anchorage. I am constantly watching local cl and FB marketplace for H6 parts cars, or H6 cars in good condition at a fair price. They are rare. There are two subaru salvage yards within 50 miles of town, and both "know what they have", and charge relatively high prices for much of their inventory. So, unfortunately, locally finding a used H6 fuel pump for a fair price is unlikely.

? Besides major parts they've already pulled for their computer inventory to sell, I've had decent luck pulling odds and ends off a couple vehicles at Northwest Auto Parts over the years. New ashtray, dome light cover, etc. I can't stand the guys out at Knik Towing & Wrecking, though, they're super rude, expensive, and not worth it usually. Admittedly, I did get a rearmost driver's side window with printed antenna from there after someone shot mine out with a BB gun on Halloween a few years ago.

 

[rkporsley]

Solved! My car is up and running again! Here's to another 232k miles ?

After replacing just the fuel pump in the old assembly I was not getting the right fuel pressure so I rented a fuel pressure testing kit at O'Reilly Auto Parts to confirm the pressure (our suspicions were confirmed with the gauge reading 0 psi) despite us hearing the new pump priming, etc.

I was getting nervous about getting to/from work (~15 miles one way) and we decided to start from square one again and pulled the whole assembly out to make sure the repaired cap and semi-stretched o-ring we carefully put back together was holding (and to possibly replace with the one I got from Berto). It looked fine and we were beginning to think of all the things that COULD cause a 0 psi reading, but then we noticed something upon closer inspection of the assembly.

Somehow the small plastic section show in the image attached was broken, but could easily be overlooked (well, we overlooked it at least). SO YEAH—somehow my cap cracked a month ago, was repaired, then the pump quit AND somehow this portion of the assembly failed (we assume due to pressure over time/wear/etc.).

We toyed with the idea of using 'aircraft grade' glue, but after this whole ordeal I just went back to O'Reilly and forked over ~$310 for a whole new assembly for peace of mind.

I drive 400-700 miles round trip a few times a year and you don't want to be stuck 100+ miles from a tiny "town" of 200 people in the middle of nowhere in Alaska and 200-300 miles from the nearest actual city due to a glue failure ???

I'm attaching the image of the plastic section that failed as well as the soldered cap which ended up getting replaced when we replaced the whole assembly.

 

[berto]

I just went back to O'Reilly and forked over ~$310 for a whole new assembly for peace of mind.

I am glad it worked out for you...I am certain your car was well worth the effort and money for this repair. Cheers to long-lived Gen 2 H6's!

 

[plain OM]

That's good news. Glad it worked out.

I'm attaching the image of the plastic section that failed as well as the soldered cap which ended up getting replaced when we replaced the whole assembly.

Looking at the photo, I can see what looks like a broken tube where the screwdriver is pointing (circled below). The lower end of that tube (far right in the photo) is the venturi pump that draws fuel from the left (driver) side of the fuel tank over to the right side where the main, electric, pump is located. The input to the venturi is fuel flow returning from the fuel pressure regulator at the front. (See attached jet pump.pdf) Each of the tubes would have a hose fitting on the top. (The third fitting on the top would be the pump output going to the engine.)

If I have that right, I'm wondering how the crack in the fuel return pipe would have caused the loss of pressure. I'm not doubting the outcome of replacing the complete assembly; I'm just trying to be able to explain cause-effect.

Is there any apparent connection between the pump (motor) output and the return line to the venturi? I'm wondering if, in addition to the return flow from the regulator, some of the pump's output is also directed to the input tube for the venturi, and with that crack, the pressure on the main pump output is being lost.

 

[berto]

@plain OM my spidey sense indicates you may be an engineer All kidding aside, I appreciate your posts on this forum!

 

[gen2lover]

@PlainOM is correct. There's really no logical reason for the fuel pressure to drop, with a crack in the return circuit. It does not seem probable for the return circuit to have any engineered connection whatsoever to the output circuit.

 

[1 Lucky Texan]

well, if the jet pump can't move fuel, gauge could show close to half tank but pump is actually dry so.....

 

[gen2lover]

well, if the jet pump can't move fuel, gauge could show close to half tank but pump is actually dry so.....

The fuel level sensor is on the pump (at least it is on the H6), so that would not happen.

 

[1 Lucky Texan]

The fuel level sensor is on the pump (at least it is on the H6), so that would not happen.

There are 2 level sensors wired to 'sum' the volume of fuel in each side of the saddle tank.

 

[plain OM]

well, if the jet pump can't move fuel, gauge could show close to half tank but pump is actually dry so.....

The idea is, indeed, possible, and I thank you for raising it in regard to my question in post #32 above.

If there's no transfer from the left side to the right, the pump could be starved after the right side is "emptied", leading to the low/no fuel pressure.

If that were the case, the low level of fuel in the right (pump) side tank might be apparent when the pump is removed. Also, if a new pump is installed without adding fuel to the tank to replenish the level on the right side, the new pump too would be starved. The jet pump can't transfer fuel from the left side to the right without first pumping fuel to the fuel pressure regulator at the engine. So a new pump would appear to not be working as well.

I don't recall @rkporsley mentioning the level indicated on the gauge, or in the right side tank when the car finally failed again and the pump was removed (post #13 above). The cap and o-ring had been fixed, and the car ran for some time before failing again. But it was also reported that fuel was coming out of the hose in the engine area, and this seemed somewhat contrary to a too low level in the right side tank.

In any event, it's certainly a possibility given that break in the return line to the jet pump.