Jim's freebie Winter Hack, Work has commenced!

could be crud in the tank blocking the gauze in the pickup or even got into the fuel line as no inline filters afaik and the tanks on those are prone to water ingress and rusting inside.

 

Cheers chap So there's 3 lines running to the fuel tap? Sounds busy.

So then Jim, you're left with (by process of elimination) that the pressure was too low to open the diaphragm or it's failing to open anyway, or you're not getting a vaccum to open it. Or something is blocking the other lines.

Test the vaccum by turning the engine over and putting a finger on the end of the vaccum pipe you unplug from the fuel tap.
Although as you adjusted the mix in the previous problem solving it's possible that the prime flow that would normally flood the bike isn't as you've dialed the mix right back.

 

no problem fella.. .
yeh in total 4 pipes on the tap... 2 incoming fuel, one outgoing and a vacuum line. nothing clearly marked either so if you dont remember to identify the pipes before you take them off then all kinds of fun . as i said quite a well known issue for the earlier design diaphragm to go kaput. must admit im not sure on what the difference in fuel flow rate is between the vacuum operated line and prime.. both technically gravity fed just the reserve/main options dont flow fuel if no vaccuum is applied therefore negating the need for an off position. but if the diaphragm isnt opening correctly or half assed then most likely gonna be making it run lean/ not at all..

 

there should be 4 screws at the back of the tap/petcock, you can get at the valve and check it over...

 

Interestingly I'm just starting work on the oldest engine set up I have to date. Although it's a Hif38

I can diagnose the sh*t out of anything but never encountered a prime line before.
So there's only 2 lines off the tank, res and on. So which line does the prime feed from? The reserve feed I'd guess? If that's the case then the lines are working and we're down to a tap issue, be it diaphragm or vaccum.

Given the fuel flows the lines themselves must be working, at least well enough to allow the engine to run. If the fuel was low then the grav. fed line wouldn't be moving serious amounts of fuel.

Jim, will the bike start / run with the tap set to on/res if the choke is left open? That would eliminate an over lean mix. If not then we're isolated to vaccum / diaphragm - as Deano has said they tend to fail it's gaining weight.

 

yeh the fuel pickup in tank is 2 level like most bikes, but the bottom of the pickup has 2 nozzles , one main, one reserve, . these then go to the fuel tap, which has one fuel line going out of it... the prime feeds from both lines as far as im aware. or alteranively the reserve as this will pick up fuel all the way down the tank.

 

lol ive tinkered with a few mini's in my time but wasnt really my thing i must admit. i can however rebuild a 3s-ge /3s-gte engine in my sleep.. . played with carbs on some v8s before too. . oldest engines ive played with is prob 69 camaro or actually thinking back prob late 50's ford zodiac mk 2 .. ( dad was a big muscle car/hot rod nut hence the fascination with greasy, mechanical type stuffs

 

Check that the rear pipe on the petlock has a good vaccum going to it.
If so its probably a hole in the diaphram in the petlock.
If not make sure the vaccum pipe isn't split or kinked and that it's connected to the left hand carb.
Alough it's not an ideal set up it;s fairly simple.

 

So is a replacement fuel tap the answer or is the Diaphragm within replaceable?

 

I will of course do all the above in the process of elimination but where's the best place to get some more rubber fuel line as mine gets shorter every time I take the tank off as it either splits or needs cutting to remove one of the lines to the tank, I have run out of spare line now so can't take the tank off until I get some more!

 

Any Motor Factor should carry lengths of fuel pipe.....just make sure you get the correct diameter. If stuck, let me know, I have several meters in the workshop

 

I have seen the diaphrams somewhere but can't remember where.
A replacement tap is £65 from Wemoto but if you have a search through the GS forum you can turn the whole mechanism through 180 degrees and it will work but you will lose reserve.
There are also a few options for other taps in there.

Wemoto Link. http://www.wemoto.com/bikes/Suzuki/GS_500_ER_ES/94-95/picture/Fuel_Tap/

 

Ditch the reserve! Do a tank range test and leave it at that, if it's a winter hack you're not going to be travelling miles out of range or anything.

 

I have been to 3 Bike shops and three Car parts suppliers, can I get the right diameter, can I f*ck, in the end I went to an agricultural supplier their's still isn't right but I'm hoping with some heat applied and gentle persuasion it'll go on, it's bright yellow hose though so looks a bit yuk!
I set up the tank and tap remote from the bike and found that by sucking through the vacum pipe all positions of fuel tap seem to be working fine, I started the bike up and could feel the carbs sucking air through the vacum hose so everything seems in order now. Going to have a cigar and cup of Cha then put it back together, watch this space for more anguished cries for help!

 

Here is the tank set up on the bench with the petcock attached, in this postition I was able to confirm the tap and vacum were working as they should by sucking on the end of the vacum tube whilst alternating the position of the tap.




The new day glo pipes, the advantage I realised after I had fitted them is that I could see the fuel running through as they are quite translucent!


Snazzy? Hmmmm!


Not too offensive if viewed from a distance and you squint!


The bike now seems to be running correctly with the tap in the 'on' position, phew, fingers crossed it lasts. Tomorrow I will be test riding it all the way to Gravesend so hopefully wont be needing the services of Green flag but will be taking my membership card just in case!

 

nice one matey... glad its working.

 

THANKS EVERYONE FOR YOUR WONDERFUL HELP, COULDN'T HAVE DONE IT WITHOUT YOU. Even when I was flumoxed, knowing you lot were still interested kept my spirits up and stopped me giving up, a great ad for the club!

 

So lets see, at £30 an hour...

Hope it runs like the wind and never lets your down, dude.

 

*Edited for accuracy*