Trying to fire on all 4s

[Detman101]

Tagged for valuable info.

Dm of mD

[Detman101]

"6. Check frame to coil mounting bolts for corrosion and clean if need be. "

Found out why my new dyna coils won't fire. I didn't bolt them to the frame...I zip tied them. I'm such a dumbass...My cousin Phillip clued me in to what I've been doing wrong. I now see why the lead wires are interchangable on the coils...the ground is in the bolts-to-frame.

Shouldn't have ruined em...right? I mean...power in...no way out...

*slap forehead*
Dm of mD

[earlfor]

When you have a spare minute, could you stop by and pick me up off the floor. My sides hurt too much to stand up. :-) :-) :-) :-) :-)

Earl
P.S. No, you wouldnt have hurt anything.........cept maybe your image. eh eh eh eh eh eh eh

"6. Check frame to coil mounting bolts for corrosion and clean if need be. "

Found out why my new dyna coils won't fire. I didn't bolt them to the frame...I zip tied them. I'm such a dumbass...My cousin Phillip clued me in to what I've been doing wrong. I now see why the lead wires are interchangable on the coils...the ground is in the bolts-to-frame.

Shouldn't have ruined em...right? I mean...power in...no way out...

*slap forehead*
Dm of mD

[Detman101]

Hehehe...glad I could provide some laughs around here instead of my usual whining hehe.


Ah...lessons learned. I never would have thought that they were grounded by the bolts hehe...
I should stop taking shortcuts.

Dm of mD

[Anonymous]

Re: got it going....

So.... I removed my plugs ( which were new.... so i figured it didnt need any cleaning after 1 hour of operation), and saw they were totally fouled !!! Cleaned them, replaced them and wow..... all 4 cylinders fired, smoothly... for about 3 minuites... then the bike appeared to be choking..... no gas ??? ..... I removed ther fuel petcock... and saw a Vacumn line connection to the back of the petcock. NOTHING CONNECTED !!!
Well.... my question !! On my carbs, There are 4 hoses at the bottom, one for each carb.... so I assume they are overflow lines.....
In between my carbs....there are 3 additional hoses..... not connected to anything.... do any or all of these somehow connect to the vacumn port on the fuel petcock ?? If not what connects there.
Thanks again... all the great advice is very helpful, and appreciated.
Irwin

I have been trying to follow along here. On my 850 the vacumn line you speak of goes from the petcock to # 2 cly. When the bike is running the vacumn keeps the petcock open and closes it when the engine is not running. So if the bike quits running in 3 min. it is probably because you drained the fuel from the carbs and the petcock is not allowing more in.

Try hooking up the vacumn line from the # 2 cyl to the petcock.

If the line is hooked up and the petcock is not working. You may get fuel pulled driectly into the # 2 cylinder and causeing problems.

Let us know what you find.
Charlie

[Anonymous]

the continuing saga....

I took apart my carbs... again, and checked the "O" rings (1978 GS750). The only O rings were on the air mixture screws and none on the main jet or pilot jet.
Last year when I got the bike, it ran... although not perfect, it was drivable, and one cylinder would cut in and cut out. ( I might have been driving with the petcock in the Prime position) However, many times, 4 cylinders operated. At that time, no line was connected to the vacumn port on the fuel petcock. This year, when I connected the vacumn line, I got alot of gas into my air box, arriving from the hose on top of the airbox.
I opened the petcock, and inspected the diaphram and filters. The filter was clean, and as i sucked ( gently ) on the hose, the diaphram did pull in the plunger( diaphram looked supple and no cracks)
I have the hose connected to carb # 3. BTW carbs # 2 and 4 have the exact same ports for hose connections, and the hose goes no where..... I hope I have the correct port connected.
Well..... after i re-checked my carbs, and cleaned my sparks... and did not connect the vacumn line, I started the bike, and it ran very well, for 3 min, then would start to speed up... slow down, and stall. I checked my plugs.... and they were totally blackened. Im wondering... could this be a question of adjustments only?? The guy who owned the bike before, never had a problem like this, and I suspect that he never had the vacumn lime connected..... since the vacumn port on the petcock had some road grime on it, when I first inspected it..... it was not clean as you would see whan a hose is connected.
PS. I also checked my floats, and they operate well.....
Thanks again to all who have been so patient with me
Irwin

[Anonymous]

Re: the continuing saga....

. ( I might have been driving with the petcock in the Prime position) However, many times, 4 cylinders operated. At that time, no line was connected to the vacumn port on the fuel petcock. This year, when I connected the vacumn line, I got alot of gas into my air box, arriving from the hose on top of the airbox.
I opened the petcock, and inspected the diaphram and filters. The filter was clean, and as i sucked ( gently ) on the hose, the diaphram did pull in the plunger( diaphram looked supple and no cracks)
I have the hose connected to carb # 3. BTW carbs # 2 and 4 have the exact same ports for hose connections, and the hose goes no where..... I hope I have the correct port connected.
Well..... after i re-checked my carbs, and cleaned my sparks... and did not connect the vacumn line, I started the bike, and it ran very well, for 3 min, then would start to speed up... slow down, and stall. I checked my plugs.... and they were totally blackened. Im wondering... could this be a question of adjustments only?? The guy who owned the bike before, never had a problem like this, and I suspect that he never had the vacumn lime connected..... since the vacumn port on the petcock had some road grime on it, when I first inspected it..... it was not clean as you would see whan a hose is connected.
PS. I also checked my floats, and they operate well.....
Thanks again to all who have been so patient with me
Irwin

When you say you have the hose connected to carb #3. Do you mean the vacumn hose? The vacumn hose goes directly from the petcock to a nipple on the #2 carb right behind the rubber intake manifold.
(Very important) Not sure where you would be hooking it up on the #3 carb? Have you checked that you are definetly getting continued fuel flow when on prime?

Have you tried running on prime? You may well have other carb issues causing the carbs to flow. Lets try to fix and eliminate one problem at a time. Bike running 3 minutes, speeding up then dying. Sounds just like one of my other bikes (Honda Reflex) would do as the carbs ran out of gas.

Do you have any gas in your oil? Check level and smell for gas.

[Anonymous]

hose connection

The vacumn hose is connected to the # 3 carb, This is what I was told I should do. Re: my carbs, the # 2,3 and 4 carbs are all exactly the same, and have a hose connection on the left have side about 1/2 way up my carb. When I 1st looked, all 3 carbs had hoses connected, with the other end not connected to anything. I examined these carbs carefully, to see is any were different.... as to where to connect from the petcock... and the only one that is different is the # 1 carb.... with no place to connect any hose.
As for oil smell.....I do not smell any gas in the oil.
New information: Another member asked me to check my battery for voltage. The battery was new in October 03 and my meter read 11 volts. I assumed my meter was incorrect as my bike seemed to turn over well. So... to test my meter, I tested it on my car... and i get 13 volts. Do I have a bad battery ??

[Anonymous]

Re: hose connection

The vacumn hose is connected to the # 3 carb, This is what I was told I should do. Re: my carbs, the # 2,3 and 4 carbs are all exactly the same, and have a hose connection on the left have side about 1/2 way up my carb. When I 1st looked, all 3 carbs had hoses connected, with the other end not connected to anything. I examined these carbs carefully, to see is any were different.... as to where to connect from the petcock... and the only one that is different is the # 1 carb.... with no place to connect any hose.
As for oil smell.....I do not smell any gas in the oil.
New information: Another member asked me to check my battery for voltage. The battery was new in October 03 and my meter read 11 volts. I assumed my meter was incorrect as my bike seemed to turn over well. So... to test my meter, I tested it on my car... and i get 13 volts. Do I have a bad battery ??

Sorry, my bad.

I just re-read the start of your post and realized you have a 78.

You have different carbs than my 1981 850. My (2) parts bikes (79) are not here so I can't check them.

Try to verify your meter against another one. I would not think your bike would turn over "well" with 11 volts. But I am not sure on that one.

Charlie

[earlfor]

Re: the continuing saga....

I have the hose connected to carb # 3. BTW carbs # 2 and 4 have the exact same ports for hose connections, and the hose goes no where..... I hope I have the correct port connected.
******************#3 carb is the correct carb to book the petcock vacuum up to.************


PS. I also checked my floats, and they operate well.....

********does that mean you measured your float levels and hooked a tube to the fuel inlet on each carb while holding it upside down and blew through it to be sure the float needle isnt leaking?

Earl

Irwin

[Anonymous]

Thank you

I was having alot of problems with my 1978 GS750, and with a very little knowledge, and alot of help, I did manage to get the bike going. Its not perfect ... yet.... but its a work in progress..... drivable... for now.
Id like to thank:
Earlfor
SqDancerLynn1
srivett
mikedr
Detman101
Landscapeman
and anyone else I forgot to mention for all their patience and great advice. It was very much appreciated.
Irwin