Fuel tap spares

[StevieB]

Hi hopefully someone may be able to help. I'm looking for a repair kit for the vacuum operated fuel tap on a USA import 1980 gs550e. Not sure of part number as the tap is different to UK as no prime position. I suspect the diaphragm doesn't open until engine running on full vacuum. Plugs dry on initial starting. Carbs, tap, filter, tank all been stripped down and cleaned. Only ones I've found are on Eblag, or m and p but don't know part number. Thanks.

[TonyGee]

ive never seen a vacuum tap without a prime ???  have you got a pic of the tap ? 

[StevieB]

Will get one taken. Assume it's for USA regs, and there's  no drain on the carb bowls. To prime you have to put a vacuum onto the tap vacuum port - then get a fuel flow.

I know it physically works as tried before fitting tank to bike. Just think required too much force to operate.

Which is why I'm after a new diaphragm. Will get some pics.

[Joseph]

Maybe you don't have the standard tap because by the looks of the microfiche the bike you have was equipped with an on/off tap.

Measure the bolt spacing of it there might be something else available new from Suzuki that would fit.

Rebuilding can be a bit hit and miss, i've usually bought new when needed for my GSXs

[StevieB]

Hi thanks for the replies. Been working shifts so just got photos of the tap on my bike tank showing just on and reserve and a corroded one from a uk 650 katana. They are totally different sizes.

Was wondering if you have a microfiche part number for my tap Joseph - would be really helpful.

Have seen on M and P website many fuel tap repair kits but no part numbers or fitment details.

Have measured outside the width of my tap:- 42.5mm approx, so maybe another way of chasing a spare as suggested.

Cheers

[TonyGee]

does your tap have 3 positions ?  like quarter past, half past, quarter too ?  or  back, down, and forward. if that makes sense.  

[Joseph]

Several parts suppliers have the microfiche available

There are some suppliers my way that sell the rebuild kit, you should be able to find something where you are

Edited March 11, 2021 by Joseph

[StevieB]

The tap has 2 positions - tried to show engraved lettering (on just shows the o).

On half past, reserve quarter to. Just operates in 90 degrees - no prime.

Looking on American websites (as where imported from) I think the tap part number is 44300-99170 or 99172.

I shall try one of my local bike garages here as suggested,they do old restorations and may have a microfiche.

And in the meantime wait to hear from M and P for any stock from my dimensions of tap seal.

Thanks for the advice.

[bomberone]

As Joseph mentioned, do you have the bolt spacing? Prob easier finding a replacement tap if it’s standard spacing.  Also is diaphragm split?  Can sometimes resurrect it by cleaning it up.

If it requires too much force is the issue with the spring? Good luck.

[StevieB]

The spring on the diaphragm is exactly what I think the problem is. I shall be taking it apart - check for part numbers and then research with local dealer. Also check online for alternative parts from dimensions.

When I get it resolved I will post source of spares back on here.

Thanks for the advice.

[Joseph]

Unlikely to be the spring. The diaphragm is what glves up usually. If the bike has recently been resurected it could be that modern fuel has melted it

[Askamaskinservice]

Looking at Partzilla, there isn't any GS550E 1980 just 1979 and then you get this:

https://www.partzilla.com/catalog/suzuki/motorcycle/1979/gs550e/fuel-cock

Which is for GS550E 1977-79 only 44300-47011

I hope this helps, Hasse.

[Poldark]

I'm in the US and have owned a few GS550's.  I don't recall any having a vacuum actuated petcock but no "prime" position.  Your bike could be a California model.  Ever since the 1960's, that state has had environmental requirements for vehicles beyond what the federal government required.  Is there a stamp or sticker mentioning California, CA, or CARB ?  Your best bet would be to replace it with a new aftermarket petcock.  Then "bin" that old "tap".

[StevieB]

Hi had the tap in bits and taken measurements of components. The circular metal "spring" plate on the back of the diaphragm is broken. Tried fabricating one but fuel outlet drips slightly. Would be ok if carb float valves seal 100% - but not ideal.

The mounting bolts to the tank have 43mm centres so I think other gs taps will fit. Haven't thought of replacing tap for just a diaphragm seal kit. Ok if new but second hand tap could need new seals!

 

I have the first original pink slip, and yes it came from California - Walnut Creek CA94596. So that explains the lack of prime.

[TonyGee]

44mm hole spacing is normal for a lot of Suzuki's  (some are 50mm) just get a tap off a gsx or something like.  they are vacuum and have a reserve. 

[StevieB]

Been researching replacement taps - nothing ever easy. Needs the 44mm bolt spacing - but tap fuel feed needs to point inwards not aft and vacuum hose needs to point fwd - needs both correct for routing and clearance.

Just can't find any that will fit - plenty on M and P and Wemeto but wrong pipe orientation. May have to give Fowlers a call. One from Eblag or breakers will no doubt need seals and I'm back to the start! Driving me mad!

[TonyGee]

find a tap with the outlet facing the way you want it and then just turn the vacuum plate to the position you need, its square so it can be repositioned 

[StevieB]

Thanks - couldn't find any 44mm spacing vacuum taps with inward facing fuel feed. But good tip with vacuum. Emailed fowlers - cheers.

[TonyGee]

can you reroute the fuel pipe ?  doesn't matter if its longer. 

[StevieB]

Was thinking the same, might get away with routing forward then get a gsx tap. Check tomorrow - cheers

[StevieB]

Phoned up Fowlers Bristol, got a fuel tap part number from the bike's vin. So it's on order (44300-49173).

Not the number I expected, will see!

Just gotta wait for shipping.

Thanks to everyone for their advice.

[TonyGee]

just had a look at the 3 suzuki taps i have, 2 gsx ( gs ) ones ( one at 44mm and one at 50mm ) plus a 1200 bandit one.  and the diaphragm's are all the same. looks like suzuki use the same type and size in a lot of their bikes.  

[StevieB]

Just got the fuel tap from Fowlers, 2 weeks delivery direct from Japan. Not bad considering current world issues and hold up in the Suez. They sourced it from my VIN number, almost exactly like original - tap has fuel and reserve but no prime. However has a brass screw you turn out to prime.

Replying to previous comment the diaphragm on my 2 taps are a lot bigger than friends gs Katana one.

So tap fitted, tested tap with a syringe on vacuum line to see at what pressure it operated. I know not an exact science but my previous tap took double the travel of the syringe to open the vacuum. So definitely better than previous.

Was thinking just press the starter and all would be well - to my disappointment it wouldn't start at all.

Spark on all cylinders, fuel in carb bowls but plugs dry.

Figure carb issues, will be starting fresh post to ask a few questions.

[Hanma-shin]

Have you tried turning the tap to ‘on’ ?

[StevieB]

Lol - a gallon in tank - set to reserve and fuel filled bowls - had carb drain off to confirm fuel getting through.