3.0L H6 on E85 = WINNING

[KiDo_Tuning]

As your aware, I prefer the whole stock fuel pump to flush the system before changing fuel pumps. Issue presents itself as soon as new fuel pump is fitted. Some people have run P100 and are still on 98 when they change fuel pumps. When an issue like this presents itself, I usually do my own testing... My DW65c being used in the fuel gantry lost fuel pressure within 6 seconds of fuel shut off, 4Kg of fuel pushing on the pump. All drains down... who knows, might be a bad batch? If so, I guess the one I have in the fuel gantry will be going back for warranty claim as it is obviously not holding.

I've seen 2 kido tuned liberties here (in Melb), with DW65 installed incorrectly. One owner even had the O ring on the wrong side of the pump and was wondering why it wasn't making pressure. Add another 3-4 who have had "double oring issues" with losing pressure. Double ringing is good in theory (in the right place), but again....A few of us non-kidos have run/still running single rings with no issues. There is an interesting pattern forming IMO.

As we've all done our own testing so to speak, I guess we do have a dilemma as to what's really going on.

Here are some vids of my "no prime starts". E85 cold and warm (warm is idling, then off for 30secs to test whether the pump will "drain back/lose pressure within 6 secs", then start)

As you can see, it takes an extra turnover when cold (it's 11C outside and I'm running one step colder sparks with e85. Which only support my results further yes, I'm changing the plugs to stock heat soon ), and warm start is perfect.



Skip to 0:35 for the ignition. The rest of the video is just to show that the pump is not getting power for 30secs.

O ring on the inlet side of the pump? Thats a new feat...

Yes, notice how your DW email said fitting 2 O rings... pinched o rings like always will leak pressure. Lube them up and issue free installs. How is it I personally have never had a DW65 install issue and that includes redoing pumps installed by workshops?

As for the whole 6 seconds thing, you dont realise how weight affects drain back... 4Kg of fuel direct above a fuel pump travels at rate of gravity through the smaller pumps orifice. The 100mL or so that is directly above the fuel pump before it self siphons is not going to take 6 seconds... can take 5 minutes or more

H6 cold start due to the compression ratio takes longer so as not to hydro the motor... only so much liquid you can fit in the combustion chamber.

FYI: My XT starts first crank / combustion stroke on E85

[Out6ack]

This was bugging me so I removed the DW65 tonight to triple check everything. I also had my laptop handy to display a bloody good downloaded workshop manual that I'd recently bought online -opened at the fuel pump page.
I noticed something within this manual's guide that I hadn't seen mentioned in either Club Lib's or NASIOC's walk through on the subject -both of which I solely referred to for my guidance during initial install.

The 4 o-rings are 2 different sizes (2X 7mm + 2X 8mm internal diameter) and MUST be installed to their correct locations or you might suffer pressure retention issues ..like I did.

I'm not to proud to raise my hand and say 'I Phukked Up!' in this instance.

I had overlooked the 1mm diameter difference between these o-rings and didn't have them located in their correct position. The walkthroughs I mentioned were very helpful and excellent guidance, but please be aware for future reference that this critical o-ring diameter and placement location is not mentioned in either guide.

So here tis..

Place a 7mm ring on the BLACK connector.
Place an 8mm ring on the WHITE connector.

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Place an 8mm ring on the DW65c pump. (This is where you can put the additional 2nd ring.)
Align the 4 slots on the pump spacer sleeve with the 4 ribs within the basket. (Well, I did anyway..)

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Place a 7mm ring on lower BLACK connector that feeds to the base of the basket.

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Done.

And umm yeah, priming problem tested ...and confirmed SOLVED.
Starts up quickly whether primed or not.

**I can only speak of my own findings, but strongly suggest to anyone having priming/starting/pressure issues to quickly check the correct placement of these o-rings.**

I'll be the one in the corner with a Dunce hat on..


Jay.

P.S. I may duplicate this post to update the 'Fuel Pump removal Gen4 Sedan' thread.

[Brunsy3.0]

This is something I have considered doing further down the track so the more info like this the better. Appreciate you throwing up your hand for what looks like a pretty easy mistake. Helps all of us learn, should never feel ashamed of admitting fault especially in circumstances like this a lot of blokes would have fixed the fault and never told others so they could potentially have same issue and never rectify.
Cheers top job

[Out6ack]

Thanks Dan.
I've generally found that the people who can't recognize and admit their mistakes are the ones who never get any better.
Besides, I think I owe it to the guys in the posts above who were scratching their heads trying to help us with the problem. Guys like Alexei, emailing companies and posting up YouTube clips, are what makes this forum so great.
Thanks to all.

[(sic)]

Awesome thanks Jay.
Does anyone know where to buy new o-rings from? Ebay/Google yields nothing for 7/8mm o-rings (well nothing under $20ea).
Might as well put new ones in incase I have pinched or damaged them.

[alexeiwoody]

Awesome thanks Jay.
Does anyone know where to buy new o-rings from? Ebay/Google yields nothing for 7/8mm o-rings (well nothing under $20ea).
Might as well put new ones in incase I have pinched or damaged them.

Buy from partsouq.com or from your dealership. Partsouq is less than half price iirc ($5-15 for an o ring from subaru).

I'll post up the part numbers for you guys

Imo best to buy genuine, as it's so hard to compare sizes with aftermarket o rings. Nearly bought a whole bag from bursons before realising the ring was off by 0.1mm-0.3mm (just remember it was some tiny amount, but definitely off)

[Out6ack]

Maybe just hold off for a bit on buying those o-rings ..(or buy an extra 8mm).
There's a question mark over the size of the ring on the pump itself that I'd like to confirm with Deatschwerks. I definitely had 2x7mm & 2x8mm rings, but the size of the pump's o-ring wasn't actually stipulated, so I naturally presumed it to be the remaining 7mm and may have hastily posted this as fact. It is possible however, that the pump's o-ring is also an 8mm, with the o-rings being mixed up during the initial install thinking they were all the same size -so I'd like to get confirmation from Deatschwerks on this first. The other connection sizes are definitely correct -it's only the pump's size I'd like to confirm. I'd hate to provide inaccurate info (hopefully I haven't already). If so, I'll post again here and edit the info if necessary.

Apologies for any inconvenience, but best to be sure.

[alexeiwoody]

Maybe just hold off for a bit on buying those o-rings ..(or buy an extra 8mm).
There's a question mark over the size of the ring on the pump itself that I'd like to confirm with Deatschwerks. I definitely had 2x7mm & 2x8mm rings, but the size of the pump's o-ring wasn't actually stipulated, so I naturally presumed it to be the remaining 7mm and may have hastily posted this as fact. It is possible however, that the pump's o-ring is also an 8mm, with the o-rings being mixed up during the initial install thinking they were all the same size -so I'd like to get confirmation from Deatschwerks on this first. The other connection sizes are definitely correct -it's only the pump's size I'd like to confirm. I'd hate to provide inaccurate info (hopefully I haven't already). If so, I'll post again here and edit the info if necessary.

Apologies for any inconvenience, but best to be sure.

I would say your installation pics are spot on. If people are careful when disassembling their stock pump setup, it's noticeable the 2 O-rings have different sizes. You just have to be very attentive to re-install the different sized O-rings exactly as stock.

It must be an easy/common mistake to make, since you're by FAR not the first person to mix the location of the rings Respect, for being honest! We don't get enough of that on here lately, and you've definitely saved someone from buying some unnecessary parts and wasting $$ and time installing it all


Here are the no.s if anyone needs:

Gasket A (smaller gasket, goes on top of the plastic spacer, ie the o ring that you can double ring into the fuel filter case) - Part no. 42025AG070

Gasket B (the slightly larger/fatter o ring) - Part no. 42025AG080



PS. Another great idea from MSR himself is to ditch the plastic spacer and just use 3-4 O-rings in its place. Why? Because now you'll have 4+ sealing surfaces in there, totally warding off any potential leaks that may form with 1 or even 2 rings, and lots more room left to reinstall. It's not how tight the pump is to click in (ie vertical pressure), it's how tightly the O-rings sit against the pump and the fuel filter walls (horizontal fit + generous lube), that matters. (Maybe make sure you're crystal clear you know what you're doing, with what size O ring, where etc if you decide to do this).

[<GB>]

I have enough trouble getting my pump out with 2 seals let alone 4 without the spacer!

is the inner diameter of the 7mm ring the same as the 8mm?

[Out6ack]

is the inner diameter of the 7mm ring the same as the 8mm?

No, the measurements relate to the inside diameter.
I used my large Phillips head as an easy guide. 8mm slipped over it, 7mm not quite.
...Awaiting confirmation reply from DW.

[KiDo_Tuning]

Another great idea from MSR himself is to ditch the plastic spacer and just use 3-4 O-rings in its place. Why? Because now you'll have 4+ sealing surfaces in there, totally warding off any potential leaks that may form with 1 or even 2 rings, and lots more room left to reinstall. It's not how tight the pump is to click in (ie vertical pressure), it's how tightly the O-rings sit against the pump and the fuel filter walls (horizontal fit + generous lube), that matters. (Maybe make sure you're crystal clear you know what you're doing, with what size O ring, where etc if you decide to do this).

Plastic spacer delete is how I usually do them. Outlawownz also had his installed by STechnic this way when I redid his. I also have one guy who has an external filter so did a hose from his DW300 pump to the tank outlet fitted... still loses fuel pressure

It was for that reason I actually tested a pump outside of the car. Actually did a video today to send to DW to find out out why this fuel gantry pump and two others I pulled out of cars have the same drain back issue

[Brunsy3.0]

Do many people run external fuel filters? Seems like a good idea ive always thought if possible to bypass stock filter and use external but then again I dont know what im talking about haha.
Correct me please

[AJ_3RB]

Jay, massive respect for your post. Thank you for putting in the extra effort and posting your findings to help people like me and many others out. My pump was fitted by a Subaru specialist and it appears they didn't get the install right either – so yeah, an easy mistake. Mine is now booked in for pump check/reinstall next week.

Alexei and Matt, thanks for pushing the point and sharing info/experiences. Especially Alexei for posting manuals and part numbers – saving noobs like me time and money. Champion.

Raptor headers to go in next... I hope they behave and go in with less fuss...

[Out6ack]

The plot thickens..
Subaru has confirmed after using my VIN, that the oring on the pump has an ID of 7mm, which is also what's indicated in their diagrams such as the ones linked here by Alexeiwoody a few posts earlier.
Chris from DeatschWerks however, has confirmed (twice) that the outlet spigot on the DW65c pump measures 8.1mm and the correct oring size to be 7.9mm.
An important thing to note here is that the 7mm Subaru rings are also slightly thinner in the wall, and when further stretched over an 8.1mm spigot may well create a less than excellent seal.
Use this info as you will people, but i think at least this has highlighted the difference in sizes and the need to pay attention to their correct placement. Yes, DW supplies orings with their pumps -maybe just don't be a boofhead and get 'em mixed up like I did..
FWIW, I currently have a 7mm installed on my dw65 and it starts fine, but DW are posting some 8's, so I'm keen to see if installing them makes it even better.

Jay.

[piercey]

iv had issues starting my engine cold where its taken quite a few cranks to start, this is with factory fuel pump running 98 with a kido tune. Is this normal or should it be starting smoothly without priming??