Petcock help

[rhalt1]

im going crazy!! im searching for a either a direct replacement petcock for a 1980 gs 750 L with 16 valves. or if any one knows where i can find a drop in no mods needed gravity feed conversion. i know i will need to put a on/off and cap off the vacuum line on the carb. my petcock has no prime and i dont feel like rebuilding it. please and thank you for the help. and im a EXTREMELY TIGHT budget so under 20 bux plus shipping would be great.

[Larry D]

You, my friend, have the dreaded '80 petcock. You could replace it with an OEM one but, you'll still have no prime and it will be well above $20.

Another option is a Pingel, again well over $20. but they will work. All you'll have to do is cap the vacuum on the carbs and turn on, and more importantly, turn off the gas when you shut the bike down

I think there is clearance issues with any other model's petcock...Do a search, there should be plenty of threads about it.

[rhalt1]

where do i do this search at google is stupid when it comes to numbers and model makes. and thank you for your help.

[DanTheMan]

If prime is the only problem with it and it shuts off and doesn't allow uninhibited gas flow, but flows right otherwise, just pull the vac line off the carb when you want to fill the bowls and suck on the vac line a bit, they'll fill right up. I found that when I want to prime mine I have to make sure I line it up perfectly in pri and it works fine.

[rhalt1]

on the petcock what is the long thing on the top that goes int the fuel tank? is that one a filter? or does it actually serve a purpose?

[chuckycheese]

Foul petcock

A couple of weeks ago, I sold my 750, which was the same year and model that you have. I put a Pingel on it about 8 years ago and it worked absolutely great.

As Larry pointed out, they are kind of 'spendy' (about 100 bucks with the adapter, which you would need). It's a tight squeeze but will fit nicely. Having a reserve is important to me and turning it off and on became so automatic, I'd do it without even thinking about it.

I never saw another petcock that would fit but, as I recall, Bill (Chef) mentioned a generic one a few years ago that was similar to the original and pretty reasonably priced.

[Larry D]

on the petcock what is the long thing on the top that goes int the fuel tank? is that one a filter? or does it actually serve a purpose?

Yep, that's the filter. What I meant by search is to search THIS site. If you click on the Tech Forum, in the the upper right is the search icon. It's a little easier to use the Advanced Search and search titles only.

[rhalt1]

ok cool and the adaptor? what did it look like? im a machinist and im trying to pull everything up on it specs and sizes wise so i make a replacement if buying one is too much.

[chuckycheese]

Adapter

ok cool and the adaptor? what did it look like? im a machinist and im trying to pull everything up on it specs and sizes wise so i make a replacement if buying one is too much.

If you're referring to the Pingel adapter, check out A1902C (which you will also find in the archives). When I bought mine, I think they were about $12 so they're no doubt more expensive now. I'm pretty sure you could make one. (I'm pretty sure I couldn't!)

[Steve]

You have no PRIME???

I was under the impression that the "dreaded '80 petcock" had a PRIME, but did not have a RESERVE.

I was under the impression that the PRIME did not operate quite like the others, though, you had to give it a bit of vacuum to get it started, then it would flow freely. In practice, this would mean that you would have to switch it to PRI, then bump the starter and turn the key off while you waited for the carbs to prime.

Am I wrong on this? Always willing to be corrected, but only when necessary.

.

[OldVet66]

It has a prime, the little hole has a nylon screw, horizontal is vacuum, vertical is prime, no reserve. His model is listed with the same stock # as mine. clean out the insect nest in there you'll see it.

[DanTheMan]

You have no PRIME???

I was under the impression that the "dreaded '80 petcock" had a PRIME, but did not have a RESERVE.

I was under the impression that the PRIME did not operate quite like the others, though, you had to give it a bit of vacuum to get it started, then it would flow freely. In practice, this would mean that you would have to switch it to PRI, then bump the starter and turn the key off while you waited for the carbs to prime.

Am I wrong on this? Always willing to be corrected, but only when necessary.

.

The dreaded '80 petcock has PRI and RUN. If it's like mine, it takes a small blade screwdriver to operate it. Mine has worked fine since I got the bike, and a RES position on a 3.2 gal tank is a bit ridiculous, as I'd be switching to reserve at 60-70 miles anyway. When mine quits working, I'll replace it with something better. The method you described for priming the carbs sounds like it should work right to me.

[chuckycheese]

Reserve

When you shorten the stand pipe on the Pingel (which must be done when used on the '80 GS750L), you can set up the reserve however you like. I had mine set to go on reserve when I had about 25, or so, miles left in the tank. The directions are in a couple of posts I wrote back then (that were still in the archives the last time I checked). It worked great!

[salty_monk]

If prime is the only problem with it and it shuts off and doesn't allow uninhibited gas flow, but flows right otherwise, just pull the vac line off the carb when you want to fill the bowls and suck on the vac line a bit, they'll fill right up. I found that when I want to prime mine I have to make sure I line it up perfectly in pri and it works fine.

Put a T connector in the Vac line & cap it off. When you want to prime remove the cap & suck on the new line... that way you can get a bit of access