Fuel pressure regulator in tank? Pointy.

After investigating my running problems (http://forums.sv650.org/showthread.php?t=165492) I decided to take the fuel system apart as it's one of the few things I haven't been through.

Injectors looked fine, not filled with crap or anything so next I took out the fuel pump - as I did I heard some thing drop off. After fishing around in the tank for a while I was rewarded with the part attached. My money is it's the fuel pressure regulator that straps to the return line at the top of the fuel pump. The Suzuki diagrams I can find label it as part of the filter, but it's got a spring inside it - so I'm not buying it!

Also the O-ring that seals it in the pump has a small chunk missing.

So, is this the SV (SK4) fuel pressure regulator and could this be causing my problems? I drained the tank first and used the pump to drain some of it. When it was priming it certainly wasn't blasting out fuel, is this normal for the SV pump?

Thanks

Jynx

Having now identified this from the workshop manual I can confirm this is the pressure regulator. I can also confirm Suzuki acknowledge it as an individual part and it comes as part of the 'filter assembly' at around £250.

I have now ordered a new o-ring from www.bearingstation.co.uk - £1.20, what a bargin!

Originally Posted by Jynx

Having now identified this from the workshop manual I can confirm this is the pressure regulator. I can also confirm Suzuki acknowledge it as an individual part and it comes as part of the 'filter assembly' at around £250.

I have now ordered a new o-ring from www.bearingstation.co.uk - £1.20, what a bargin!

I am having the same problem. Has been plaguing me for a month now. Only issue is i cant get my hands on a fuel pressure regulator to save my life. I understand that its part of the fuel filter assembly, but when i go to http://www.suzukipartshouse.com/ its not listed as a separate part, also cant find it on ebay or any local salvage yards. Is there anyway that you still know the part number to the fuel pressure regulator to help narrow down my search?
Please and Thank You!

[yorkie_chris]

The stock pump can really wazz quite a bit of fuel out.
On parts fiche it shows it as part of the high pressure filter IIRC.

Personally I'd find a used pump, there are enough out there and from GSXRs and stuff too.

Vedi,

I only replaced the O-ring, it was that which caused my problem. Do you think your regulator is at fault or has it become dislodged like mine?

Suzuki will only sell you the whole assembly, complete nightmate.

AH HA!! So the problem with my bike was the throttle bodies! I'm not a mechanic but I do have a good mechanical understanding of what was going to so i will do my best to break it down. Short version they were very out of sync. The adjustment that was needed to be done was mostly on the front cylinder, a little tweaking on the rear. At idle the bike would barely run because the front wasn't firing but if you pulled back the throttle it seamed to be fine with a little hick up and some power loss. It was running way too lean. And then when you would decelerate and pull in the clutch (I engine brake, I know bad habits) the gas would go flooding into the front and fouling out the plug. Which led me down the wrong path initially in figuring this thing out. Take it to a mechanic and get it done right, its not too expensive (cost me 1.5 labor hours, 120$ but i have an awesome mechanic that gives me deals) Hope others of you who are having the same issue find this to be the cure! Let me know I'm interested!

[Winder]

Jynx do you remember the size O-ring you ordered? I have put everything back together until next week and don't have time to pull the fuel pump out for a few days yet.
I had the same problem, high pressure regulator fell out and when pushed back into the pump assembly it doesn't feel very secure. I imagine a new O ring could solve the problem.

Cheers

Ok, after some digging I found found my original invoice.

I remember the O-ring being a bit of a funny size and I ended up ordering an imperial size, as it was the closest match. I can't really say if it is the 'right' size or not but it was 3 years ago and I haven't had a single problem with the running of the bike since then.

As mentioned before I ordered from Bearing Station (http://www.bearingstation.co.uk/) and it's still at the low low price of £1.20! The code you need is: BS203. Put that into the search and you should find:

BS203 - Nitrile O Ring 0.313" x 0.139"

Hope it solves your problem

Jynx

[Winder]

Thanks mate, i'll get one ordered now. Means i can do the job all in one go when it gets here. I did find the exploded diagram of the fuel pump online but the O ring doesn't have a part number. What a pain!

Thanks again

[Winder]

Got an hour free this morning, changed the o-ring over and bike now runs! Took it for a test ride and gave it a bit of a thrash and all is good.

Thanks for your help.