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Trouble with oil and fuel 1978 gs750
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Mocks
If the valves are not properly shimmed and/or adjusted that wouldn't lead to oil bypass would it? Thanks for ALL the quick and knowledgeable replies everyone!
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Originally posted by Mocks View PostI went ahead and ordered the factory service manual for it.-Mal
"The only reason for time is so that everything doesn't happen at once." - B. Banzai
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78 GS750E
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Mocks
No, this is the first I've heard of a FREE manual. I just paid $47 for one, dang! Oh well, have one in my hand before long.
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MisterCinders
If the plug is black underneath the wetness, then may be rich and/or mis-adjusted timing. If the wetness itself is black, then it is oil-fouled. Compare the plugs to the images here:
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Is your bad cylinder #3? The one with the vacuum line? Does your oil smell like gas?
Are you saying you haven't read the Basscliff site? You did get the Megawelcome, right?
Also, Since the guy who "cleaned" your carbs apparently knows very little about carbs, you might want to consider completely redoing them. The VM tutorial is on the BC site.Last edited by Big T; 05-23-2012, 04:57 PM.1978 GS 1000 (since new)
1979 GS 1000 (The Fridge, superbike replica project)
1978 GS 1000 (parts)
1981 GS 850 (anyone want a project?)
1981 GPZ 550 (backroad screamer)
1970 450 Mk IIID (THUMP!)
2007 DRz 400S
1999 ATK 490ES
1994 DR 350SES
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Mocks, step away from your motorcycle.
Go back to post #3 and check out all the links BassCliff has provided. You must do the donkey work and read up on your machine before you can expect to get it running right. Yeah, it's a pain but it has to be done. You won't regret it.-Mal
"The only reason for time is so that everything doesn't happen at once." - B. Banzai
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78 GS750E
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Mocks
And on top of this I don't think my needles seat due to the fact that fuel dumps outta the bowl drains. Could a needle being set too far low/high keep it from seating properly? They look good, but I'm not for sure where the PO set them(if he even did). I know my petcock works, so its not that.
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MisterCinders
If the floats are really low, you might flood out the tubes. More likely, your needle valves are sticking or the floats are snagging on something like the bowl gasket.
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Mocks
Floats are free, but I'm not sure if the needles are sticking or not. Are the complete carb kits on eBay worth it or are they junk?
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Originally posted by Mocks View PostFloats are free, but I'm not sure if the needles are sticking or not. Are the complete carb kits on eBay worth it or are they junk?-Mal
"The only reason for time is so that everything doesn't happen at once." - B. Banzai
___________
78 GS750E
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MisterCinders
Originally posted by Mocks View PostFloats are free, but I'm not sure if the needles are sticking or not. Are the complete carb kits on eBay worth it or are they junk?
To check your needle valves and seats, you can do two things.
First, pull the needle and seat out. Clean it off and then blow through the bottom of the seat as you gingerly push in the needle. Once it seats, you should feel it seal up and your cheeks will puff out like you are blowing a balloon. Otherwise, the needle is not seating properly and you need to clean out the seat and possibly replace that set.
If they all pass the blow test, you need to figure out whether fuel is slipping past the needle/seat o-ring. Put the carbs back together but leave the float bowls off. Then stand the rack up in a catch basin. I use a big oil change pan, but even a big foil casserole pan will work. Prop or hold it up from the bottom since you don't have bowls there. Then run fuel through the line.
You should see fuel coming through each needle valve. Gently lift the floats to make sure that fuel flow stops. It should only take about 30 seconds to check all 4 floats, so you won't be spilling a ton of gas.
If fuel drips or dribbles in with the float up, the needle seat o-ring is failing and needs to be replaced.
If both tests are clean, the last thing to check is the float movement. Even if they move nicely, you should double check that movement with the bowl gasket in place. I had one float that kept snagging on the edge of the bowl gasket, but it moved fine when I pulled the carbs apart.
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Originally posted by Mocks View PostDo you mean while attatched to the rail and bolted together?-Mal
"The only reason for time is so that everything doesn't happen at once." - B. Banzai
___________
78 GS750E
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Mocks, have you been to Basscliff's site yet and read through your mega-welcome? If not, please put down the tools and do so very quickly. It will save you lots of heartache if you follow the recommendations of all the extremely knowledgeable folks on this forum.Cowboy Up or Quit. - Run Free Lou and Rest in Peace
1981 GS550T - My First
1981 GS550L - My Eldest Daughter's - Now Sold
2007 GSF1250SA Bandit - My touring bike
Sit tall in the saddle Hold your head up high
Keep your eyes fixed where the trail meets the sky and live like you ain't afraid to die
and don't be scared, just enjoy your ride - Chris Ledoux, "The Ride"
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