After Carb Rebuild

[Guest]

Tried searching, but I usually break the site when I search stuff with carb in it

I just finished a carb rebuild and put pods in on my 81 GS450s. Hooked everything back up but the engine won't start. I know I can check if fuel is getting to the carbs by opening one of the bottom screws on the carbs. How do I get fuel flowing to the carb? My petcock only has On and Reserve, no prime.

[BassCliff]

Hi,

Did you have to re-jet for the pods? Did you bench sync the carbs after reassembly? You can remove the plugs and put a spoonful of gas in each cylinder to see if it fires. Are you still using a vacuum petcock? Is the vacuum line connected properly?

Thank you for your indulgence,

BassCliff

[jmaresca]

Hi,

Did you have to re-jet for the pods? Did you bench sync the carbs after reassembly? You can remove the plugs and put a spoonful of gas in each cylinder to see if it fires. Are you still using a vacuum petcock? Is the vacuum line connected properly?

Thank you for your indulgence,

BassCliff

I put in a 142.5 main jet, from some research to start. I did not bench sync, I will have to find out how to do that. I'm still using the stock petcock, so I'm assuming vacuum. The two lines were connected properly(black line with a metal L, and tan line directly to the carb), although after going to pods, I have an extra black line coming from the top of my engine directly under my tank. I will try removing the plugs and putting some gas in tomorrow.

[Steve]

I was under the impression that only the "dreaded '80 petcock" had only two positions, and they were ON and PRIme.

Are you SURE you don't have a PRIme position? If you turn the lever clockwise, so it is pointing forward, it will be in REServe.
Pointing down will be the ON (or RUN) position. Rotated anti-clockwise so it is pointing to the rear is PRIme.

.

[jmaresca]

I was under the impression that only the "dreaded '80 petcock" had only two positions, and they were ON and PRIme.

Are you SURE you don't have a PRIme position? If you turn the lever clockwise, so it is pointing forward, it will be in REServe.
Pointing down will be the ON (or RUN) position. Rotated anti-clockwise so it is pointing to the rear is PRIme.

.

It doesn't go anti clockwise, only 6 and 9 oclock

[cowboyup3371]

Sounds like you'll need a new petcock; contact Z1 as they do sell ones that will fit well.

[jmaresca]

Sounds like you'll need a new petcock; contact Z1 as they do sell ones that will fit well.

What should I ask for? A non-vacuum petcock? They have this and this but they're both vacuum. Could I swap out a petcock from another model?

How do people normally get a vacuum petcock primed?

[tkent02]

It doesn't go anti clockwise, only 6 and 9 oclock

There's your problem, that petcock is WAY too big.

[hardline_42]

I was under the impression that only the "dreaded '80 petcock" had only two positions, and they were ON and PRIme.

Are you SURE you don't have a PRIme position? If you turn the lever clockwise, so it is pointing forward, it will be in REServe.
Pointing down will be the ON (or RUN) position. Rotated anti-clockwise so it is pointing to the rear is PRIme.

.

I'm a complete noob with these bikes, but the petcock on my '81 GS450E is identical to the one pictured. The "reserve" position does double duty as "reserve" and "prime," if I'm not mistaken.

[jmaresca]

I'm a complete noob with these bikes, but the petcock on my '81 GS450E is identical to the one pictured. The "reserve" position does double duty as "reserve" and "prime," if I'm not mistaken.

Howdy from Cherry Hill! Just updated my location. I'll have to give that a try tonight. I've also read a few ways of priming by manually sucking gas into the carbs using a hose. I'm sure my neighbors are glad I couldn't get it fired up last night at 11PM.

[tom203]

....

How do people normally get a vacuum petcock primed?

Just put a section of hose on petcock's vac nipple and suck on it- fuel should flow easily.

[hardline_42]

Howdy from Cherry Hill! Just updated my location. I'll have to give that a try tonight. I've also read a few ways of priming by manually sucking gas into the carbs using a hose. I'm sure my neighbors are glad I couldn't get it fired up last night at 11PM.

Hey you're right down the highway! MY neighbors would probably have preferred the sound of a running bike than what they heard from my garage last night. Namely, me cursing and yelling for two hours wrestling the airbox out of my frame. Can't wait until it's time to put the new one in, but a carb rebuild and a shipment of parts need to happen first. Good luck with your bike. I'll be checking in on the thread to see your progress.

[jmaresca]

Hey you're right down the highway! MY neighbors would probably have preferred the sound of a running bike than what they heard from my garage last night. Namely, me cursing and yelling for two hours wrestling the airbox out of my frame. Can't wait until it's time to put the new one in, but a carb rebuild and a shipment of parts need to happen first. Good luck with your bike. I'll be checking in on the thread to see your progress.

I feel your pain. Took my brother and I a half hour, a solid pipe, and a cutting wheel to get it out. Bent most of the frame tabs. Luckily they'll be grinded off at some point.

[pete]

You do have prime!

Like me, you just didn't know it

That little brass screw beside the tap there... undo it a turn or two, wait 30 seconds, do it back up. Primed

[jmaresca]

You do have prime!

Like me, you just didn't know it

That little brass screw beside the tap there... undo it a turn or two, wait 30 seconds, do it back up. Primed

This partially helped, so thanks. The real issue was more sinister and amateur. I mocked up a wood plate to mount all of my electronics to. Turns out the starter grounds through the original plate. Once I grounded it, I got it to start. Now, its time to figure out my stuck throttle.

Thanks for the help.