fuelcock/petcock replacement

[sacruickshank]

One thing I discovered when mounting on the bike is there a potential routing issue for the fuel line. The fuel nozzle on the oem points to the front into open space. On these the nozzle points to the inside of the bike and on the 850 the opening is less than an inch from the side of the airbox. I first tried routing the line by the most direct route turning it toward the front. Because of the tight space however that created a crimp in the bend.

I ended up routing the line from the carbs over the top of the airbox and down to the petcock nozzle which was still a tight fit but straight enough that there was no crimping.

It is not a deal breaker. Just keep in mind that you may have to do a little work around. I also thought about using some thick walled marine hose that I had in the garage for the line. It is stiff to work with, but it is not going to crimp.
...

I bought a pack of 90 degree brass elbows that allow more creative routing without bending the tubes alot. I've had cheap plastic fuel filters break due to the pressure from teh bends

 

[dpep]

I bought a pack of 90 degree brass elbows that allow more creative routing without bending the tubes a lot.

Good idea. Do you have more detail on the product--picture or link perhaps? Most of what I saw was threaded and/or too thick to serve the purpose; hence the resort to thicker fuel line. But s proper fitting elbow would for sure be the better option.

 

[Guest]

Just received my "Chinese Petcock" ordered through Amazon but believe all sellers are selling the same junk. Before going whole hog and installing the tank on my bike I tried the new petcock. It seemed to hold gas adequately and did not drip when installed in the tank. However, when I applied vacuum with a small hand vacuum pump to check how it operated as it would on the bike, it flowed fuel in Res. & On position. A problem arose when I removed the vacuum and the petcock continued to drip fuel. I now have a new petcock that has the identical problem to the 43 year old one that I was trying to replace. Looks to me like it is a crap shoot when ordering these knock offs. It may well be that you might have to order several before finding one that works properly. I have no intention of using the new one thinking that it will leak fuel and likely drip gas on to my shop floor creating a severe fire hazard. Gorminrider had it right when he asked how the petcocks resealed after vacuum was applied.
Don't know what to do now as I don't want to start ordering Chinese knock offs and waiting several weeks to find out the replacement is just as crappy as the one I received today after waiting over 3 weeks. The one I ordered was supposed to be and was advertised on Amazon as "shipped from Canada" but the seller (Topzan) was fraudulent when posting the ad and it was shipped from China.Really got taken here as I paid extra $ due to the seller stating my order would be shipped from Canada and thus would save waiting time. The ad is here: https://www.amazon.ca/gp/product/B082FFL5GR/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Anybody have any other thoughts about what to do to repair/ replace my 1979 GS 850 petcock.

 

[Rich82GS750TZ]

Jonesz, did you look for one here? https://www.georgefixs.com

 

[Guest]

Jonesz, did you look for one here? https://www.georgefixs.com

I had emailed them two inquiries before ordering the chinese one from Amazon. No answer either time. I did see where another poster had recommended Georgefixs but?

 

[Guest]

I seem to recall that they will not ship to Canada but was going to have it shipped to Az. where a friend was wintering and advised Georges of that. So was left wondering.

 

[rphillips]

Post number two & post number thirty six will work at least "as good", or "maybe better". And a bit cheeper. I'm trying to figure what have you got to lose.

 

[Guest]

Post number two & post number thirty six will work at least "as good", or "maybe better". And a bit cheeper. I'm trying to figure what have you got to lose.

Yep I hear ya and have so far tried this with my oem fuelcock:
- bought the selector side rubber innards oem from dealer and installed after cleaning the inner plate on a sheet of glass with 2000 grit
-Took apart the diaphragm (holds vacuum/not perforated)side and cleaned up the seat a bit with fine compound, reinstalled after stretching the spring some. Was not able to find proper/exact sized oring for the seat so used the old one.
-the plunger mechanism with oring that seals to stop the gas flow appears to seat somewhat off center after releasing the vacuum have no idea why. The bike a 1979 GS850 has 17000 kms/ just over 10,000 miles and I am thinking that the plunger is not worn out but?
-Maybe tomorrow I will take the new Chinese one apart and stretch the spring a tad or perhaps move the oring frpm the new Chinese petcock to the original petcock if they are the same size
-Really would like to get this fixed as have lost faith in the petcock shutting off the fuel. Have even emailed Pingel as to which of their petcocks they recommend but no answer from them. Lots of bux for their petcocks but can't find an oem one
Anyway thanks for your help. Will post if anything changes

 

[rphillips]

Seems you've tried most all options. Not much to say but Good luck.

 

[93Bandit]

Just received my "Chinese Petcock" ordered through Amazon but believe all sellers are selling the same junk. Before going whole hog and installing the tank on my bike I tried the new petcock. It seemed to hold gas adequately and did not drip when installed in the tank. However, when I applied vacuum with a small hand vacuum pump to check how it operated as it would on the bike, it flowed fuel in Res. & On position. A problem arose when I removed the vacuum and the petcock continued to drip fuel. I now have a new petcock that has the identical problem to the 43 year old one that I was trying to replace. Looks to me like it is a crap shoot when ordering these knock offs. It may well be that you might have to order several before finding one that works properly. I have no intention of using the new one thinking that it will leak fuel and likely drip gas on to my shop floor creating a severe fire hazard. Gorminrider had it right when he asked how the petcocks resealed after vacuum was applied.
Don't know what to do now as I don't want to start ordering Chinese knock offs and waiting several weeks to find out the replacement is just as crappy as the one I received today after waiting over 3 weeks. The one I ordered was supposed to be and was advertised on Amazon as "shipped from Canada" but the seller (Topzan) was fraudulent when posting the ad and it was shipped from China.Really got taken here as I paid extra $ due to the seller stating my order would be shipped from Canada and thus would save waiting time. The ad is here: https://www.amazon.ca/gp/product/B082FFL5GR/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
Anybody have any other thoughts about what to do to repair/ replace my 1979 GS 850 petcock.

Yep, you confirmed my suspicions (I was the first to ask how well it re seals after vac has been applied and then released, then Gorminrider reafirmed my theory.)

This is disappointing for sure but seems to align with the majority of peoples experiences with these petcocks. I haven't had a chance to order one yet, so I guess I'll try rebuilding my OEM petcock with the kit that's been sitting on my shelf for a while. Getting tired of fuel puddles on the shop floor. Probably won't have much better luck but idk what else to do.

 

[Guest]

Yep, you confirmed my suspicions (I was the first to ask how well it re seals after vac has been applied and then released, then Gorminrider reafirmed my theory.)

This is disappointing for sure but seems to align with the majority of peoples experiences with these petcocks. I haven't had a chance to order one yet, so I guess I'll try rebuilding my OEM petcock with the kit that's been sitting on my shelf for a while. Getting tired of fuel puddles on the shop floor. Probably won't have much better luck but idk what else to do.

Going to try a couple of things as noted in my last post but am busy for next couple of days. Will let you know how I make out. Fuel puddles are my concern too!!

 

[Gorminrider]

Yep I hear ya and have so far tried this with my oem fuelcock:
- bought the selector side rubber innards oem from dealer and installed after cleaning the inner plate on a sheet of glass with 2000 grit
-Took apart the diaphragm (holds vacuum/not perforated)side and cleaned up the seat a bit with fine compound, reinstalled after stretching the spring some. Was not able to find proper/exact sized oring for the seat so used the old one.
-the plunger mechanism with oring that seals to stop the gas flow appears to seat somewhat off center after releasing the vacuum have no idea why. The bike a 1979 GS850 has 17000 kms/ just over 10,000 miles and I am thinking that the plunger is not worn out but?
-Maybe tomorrow I will take the new Chinese one apart and stretch the spring a tad or perhaps move the oring frpm the new Chinese petcock to the original petcock if they are the same size
-Really would like to get this fixed as have lost faith in the petcock shutting off the fuel. Have even emailed Pingel as to which of their petcocks they recommend but no answer from them. Lots of bux for their petcocks but can't find an oem one
Anyway thanks for your help. Will post if anything changes

O .gee. bummer but yes BEYOND the petcock just needing a breakin period....and I'm just on about the "sealing" not the "reserve" issue...

Measure spring original height FIRSTbefore stretching spring BUT please read on..I think*.what stretching does is similar to preloading your shock spring SO another option is to preload the spring just like people do with their forks...an insert. Reason being that the "force" of springs is "linear" it goes up in a linear way as its length is changed, so changing the length (stretching OR compressing) puts you further along the force graph..ie: increases. What doesn't happen is the spring gets "stronger" .Youve just moved along its "collapse" scale.It'd want thicker wire to make it stronger in a true way...

an insert is Worth a try versus wrecking the spring just yet because it's hard to UNstretch it.
ANOTHER try is to use a different spring or ADD a spring...same size or smaller can live in the space available with it.
PLUS You can MAKE a spring from guitar string

* "think" as in correct me if I am wrong but do it in a way that I can understand

 

[Guest]

Post number two & post number thirty six will work at least "as good", or "maybe better". And a bit cheeper. I'm trying to figure what have you got to lose.

So post to advise that the seller of the Chinese petcock that I had purchased refunded my purchase price after I filed a return item request on Amazon. I thought that was very responsible way of dealing with my problem of receiving a product that did not function properly. In addition they only required a couple of pics and an explanation not requiring the item to be returned. Shipping costs are prohibitive in Canada for items of this value. So following Rphillips post figuring there was nothing to lose I disassembled the diaphram side of the Chinese petcock and removed the small Oring on the plunger. I then put that Oring on the old oem petcock that I had already rebuilt with all but the Oring and gave it a try. Lo and behold the old petcock not longer dripped when tested with a hand vacuum pump so I installed it back in the tank and put it on my bike. Two days now and no overflow drips on the floor under my bike after running it a few times to check. Sorry that I did not measure the Oring from the Chinese petcock and don't want to take things apart to do so. It appears that my drip problem with the oem petcock was solved though. Hooray it was driving me nuts! Will now let you get back to the original posts intention and cease my hijack but hope this info helps. Appreciate the help & advice from everyone.

 

[Gorminrider]

^^ good news! (I've done similar with brake Master cylinders) But I can't help wondering if your carb float needles also need work...my carbs don't overflow even on PRIME...not usually anyways.
.
The price has sure gone up Mine was 27.99 from Triumilynn on amazon.ca.(That seller has run out presently. I'm not sure but i think i got free shipping when I bought something else to make it up to the $35)..
All this made me nervous so I went out and double checked its operation disconnected from carbs and test suction operation but it's still working fine on the GSX400T....

 

[Gorminrider]

One thing I discovered when mounting on the bike is there a potential routing issue for the fuel line. The fuel nozzle on the oem points to the front into open space. On these the nozzle points to the inside of the bike and on the 850 the opening is less than an inch from the side of the airbox. I first tried routing the line by the most direct route turning it toward the front. Because of the tight space however that created a crimp in the bend.

I ended up routing the line from the carbs over the top of the airbox and down to the petcock nozzle which was still a tight fit but straight enough that there was no crimping.

It is not a deal breaker. Just keep in mind that you may have to do a little work around. I also thought about using some thick walled marine hose that I had in the garage for the line. It is stiff to work with, but it is not going to crimp.
...

Yes they are kinda chunky. Good point about the routing of fuel lines and vacuum too- a thi nwalled hose can kink shut badly routed, especially if it's too near heat

but ,It's quite an ok fit on my 81 GSX400T with a teardrop tank (so similar to GS450T in USA) . I haven't tried it on my E where the petcock is mounted further back on the squarish tank. ...

 

[Guest]

^^ good news! (I've done similar with brake Master cylinders) But I can't help wondering if your carb float needles also need work...my carbs don't overflow even on PRIME...not usually anyways.
.
The price has sure gone up Mine was 27.99 from Triumilynn on amazon.ca.(That seller has run out presently. I'm not sure but i think i got free shipping when I bought something else to make it up to the $35)..
All this made me nervous so I went out and double checked its operation disconnected from carbs and test suction operation but it's still working fine on the GSX400T....

Yep I will try the float needles on prime after driving the bike a bit and getting the bike out of my small shop and outside They were cleaned and float levels set but? The bike hasn't been driven for 20 years so am going to drive it a bit before digging any further but will recheck the floats and needles after a couple of longer rides.I did note that I initially had to tap the cabs with a screwdriver handle a couple of times to get the number 4 carb overflow to stop but that has happened to me before after bikes have had a longish layover. Thanks for the tip. Edited for the carb number

 

[rphillips]

There it is, it's happened again. the above post ^^^ Jonesz did not type in that Groups, he put in a # & it came up as a link to Groups. I've seen this kind of thing a few times since the new layout... Very strange!!

 

[rphillips]

And yes, like Grom said, hard to know your petcock ain't working unless a needle & seat ain't working properly, & hard to know a needle & seat ain't seat ain't working unless your pet cock ain't working properly. Not always but most always.

 

[dpep]

I wanted to follow up on the issue of leak after vacuum. I did not apply vacuum during my bench tests because I did not know if it would accurately simulate operation on the bike. The better way would be to pull off the line and check for drips after running the engine for a while.

As it turned out after running a few test miles I had to pull my carbs. I removed the tank to a table in the garage. That was a week ago now and none of the gas in the tank has leaked out. Having seen the issue Jonesz had I went out and tilted and shook the tank in both On and Res with still no fuel escaping.

My observation would be that it is either the luck of the draw or there is something about applying external vacuum that affects the works differently. Could the seating of the diaphram be altered by vacuum force in excess of normal operating levels? I don't know; just throwing that out as a possibility. In any case I would recommend checking after running.even if it is an extra step.
...

 

[dpep]

& hard to know a needle & seat ain't seat ain't working unless your pet cock ain't working properly.

Just leave it on Prime.