1982 Suzuki GS1100G Carbs Overflowing into Airbox.

[Rijko]

If it was me I'd be checking the coils. It could be an ignition problem..
And the plug wires and caps.

(Just a guess, and worth its weight in snake oil.)

Yep. 1&4 are on the same coil.
These coils are very durable, so check if it's getting 12 volt.
And if so, check if it is getting a pulse from the points on the trigger cable.

[GalDemSuga]

If it was me I'd be checking the coils. It could be an ignition problem..
And the plug wires and caps.

(Just a guess, and worth its weight in snake oil.)

How do I test the coils outside of looking at a plug hanging loose in either wire. I have verified that all plugs spark. Now cylinders 1 and 4 were the two that didn't ignite even with spark. These two cylinders had the tight valves.

[GalDemSuga]

Yep. 1&4 are on the same coil.
These coils are very durable, so check if it's getting 12 volt.
And if so, check if it is getting a pulse from the points on the trigger cable.

They both spark when I placed a loose plug in them.

[Big T]

How do I test the coils outside of looking at a plug hanging loose in either wire. I have verified that all plugs spark. Now cylinders 1 and 4 were the two that didn't ignite even with spark. These two cylinders had the tight valves.

You look in the factory service manual and break out the voltmeter

[GalDemSuga]

You look in the factory service manual and break out the voltmeter

I just looked it up and it is straight forward enough.

[GalDemSuga]

Today's Update:

I have rebuilt the Auto Tensioner and the Tach Gear Assembly. I installed the Auto Tensioner and tested its operation according to page #112 of the Suzuki Manual. The Carbs are back together and bench synced. The Airbox has been rebuilt as well. I am awaiting the three shims to correct Cylinder 1 and 4 valve clearances.

I tested both coils and the resistance was about 4.5 ohms. The wires to the coils from the left side coil and beginning on the left side post of each coil are; orange/white and white and orange/white and black/white. I hope that the wires are correct as that is how they were when I got the bike. I got "OL" when checking the signal generator resistance, so I dropped a plug in each wire and got spark on all Cylinders.

[GalDemSuga]

Update:

The engine was put back together and all valve clearances are finally within spec. I installed the Carbs and Airbox and then attached my Aux Tank. The bike started with full choke and with the Air Screws set @ 3 turns out as suggested by fellow member Steve. It fired up almost immediately and ran @ 3000 rpms. After it warmed up, I was able to slowly close the choke but I had to increase the Idle Adjustment Screw until finally I had it idling at 1100-1200 rpms. I kept the Air Screws @ 3 turns out as I intend to work at syncing the Carbs later on.

I then shut the bike off to check for leaks and initially I saw none. I was about to zip-tie the spark plug leads up and off of the valve cover when I saw gas on the engine below the Airbox. I pulled the Airbox and it was full of gas. Carbs 1, 3 and 4 were leaking out of the main bore and a small hole on the outside of the main bore. It was pouring out of them like nobody's business. I have attached a video below showing the issue:

https://youtu.be/X4Ai6ubbTgk

Tomorrow I will look at the Carbs again The good news is that the Auto Tensioner and Tach Gear rebuilds were done right!! Thanks Guys for the pointers.

[Steve]

I've been waiting for Steve to reply regarding the tensioner, but it seems to me you need to loosen the lock-nut, turn the screw out to release the plunger completely. Turn the screw in until light resistance is met, then back the screw out 1/2 to 3/4 of a turn and tighten the lock-nut taking care to hold the screw in place. I have no issues with this method.

OK, Steve finally saw this.

The stock tensioner has the plunger rod that actually pushes on the slider that pushes against the chain. There is a notch in the side of that plunger. When the plunger is fully retracted, the setscrew (which is in the area of the notch) will be at the front of that notch and can be tightened to lock it in the retracted position.

If you want to experiment a bit BEFORE putting the tensioner in the engine, try this. Retract the plunger, lock it in place with the set screw. Release the set screw, note that the plunger will extend about 3/4 inch. This happens with the first movement of the set screw. In normal operation, the plunger might only move 3/8 to 1/2 inch when installed. Continue turning the set screw. Note that at about 3/4 turn, the plunger is pushed completely out of the housing. By limiting your release movement to 1/2 turn, the plunger will stay in the housing.

Back to installation: With the plunger fully retracted and locked in place, put the tensioner assembly (with gasket) into the back of the cylinder block and torque the mounting screws. Release the plunger by turning the screw 1/4 to 1/2 turn, then use the lock nut to hold it in that position. This will allow the plunger to move to maintain tension as the chain wears, without the possibility of coming loose.

.

[GalDemSuga]

OK, Steve finally saw this.

The stock tensioner has the plunger rod that actually pushes on the slider that pushes against the chain. There is a notch in the side of that plunger. When the plunger is fully retracted, the setscrew (which is in the area of the notch) will be at the front of that notch and can be tightened to lock it in the retracted position.

If you want to experiment a bit BEFORE putting the tensioner in the engine, try this. Retract the plunger, lock it in place with the set screw. Release the set screw, note that the plunger will extend about 3/4 inch. This happens with the first movement of the set screw. In normal operation, the plunger might only move 3/8 to 1/2 inch when installed. Continue turning the set screw. Note that at about 3/4 turn, the plunger is pushed completely out of the housing. By limiting your release movement to 1/2 turn, the plunger will stay in the housing.

Back to installation: With the plunger fully retracted and locked in place, put the tensioner assembly (with gasket) into the back of the cylinder block and torque the mounting screws. Release the plunger by turning the screw 1/4 to 1/2 turn, then use the lock nut to hold it in that position. This will allow the plunger to move to maintain tension as the chain wears, without the possibility of coming loose.

.

The Auto Tensioner got a good rebuilding and I installed and tested as per the Suzuki Manual page #112. I was able to verify it moves freely on its own via that test the manual calls for. The bike ran good yesterday and I didn't hear any weird noises out of the engine. I was able to use the throttle and in each instance the engine responded good. I am now back to the Carbs, see the video link below. I had that Aux Tank too high (3-4 feet) above the bike. It was hanging from the garage door track and now I know that there was no way the float valves can handle that pressure after I shut the engine down. It was a "Here's Your Sign Moment" mistake to have it up there, lesson learned. I want to redo carbs (3rd time) but this time thoroughly. I need to know if its safe to dip the bodies with the throttle plates (butterfly) still intact. I will remove the Choke plungers.

Update - https://youtu.be/ImxL4DaoRxk

[Grimly]

If the float valves can't handle a fuel head of 4ft, they need replaced.

[cowboyup3371]

Yes, follow Nessism's Carb Rebuild instructions to the letter (can be found on Basscliff's Site - http://members.dslextreme.com/users/bikecliff)

[GalDemSuga]

Yes, follow Nessism's Carb Rebuild instructions to the letter (can be found on Basscliff's Site - http://members.dslextreme.com/users/bikecliff)

I used the guide but didn't dip the Carb bodies, I will now.

[GalDemSuga]

If the float valves can't handle a fuel head of 4ft, they need replaced.

I used a K&L o-ring kit (Ebay) when I rebuilt the Carbs. I won't ever do that again. I noted that not all of the float valve seats were snug while I was disassembling them this time, except for Carb 2 which was snug. I was able to pull the seats out with my fingers very very very easily and then to pinch those o-rings off very every very easily with my fingers. They were all snug when I assembled the Carbs. That looseness had to be the material reaction to the gas. I can now compare those o-rings with the ones from Cycleorings.com (Robert Barr). It is possible that the leaks were past the o-rings as opposed to the float needle valves. I hope that was the case. The needle valves look great with no pitting or dulling in the tips and the springs function freely.

[GalDemSuga]

Update:

I thought I had it all sorted for a good hour but after several restarts which were buttery smooth and easy as cake, did I say easy as cake and I mean easy easy easy, Carb 1 is f@#$%&g leaking. I need to change the float needles. Now I have to find them.....UUUGHHHH. Man I am so close.

video = https://youtu.be/y8O32VMjZl4

[GalDemSuga]

Update:

I tired to seal up Carb 1 but then Carb 2 started leaking as well. Upon closer inspection, its the float tabs that are contacting the valve seats and therefore not shutting off the valves. I bent down the tabs to get the 22.40 mm needed for the float height but seeing that the valves must be worn it then results it the tabs hitting the seats.

I just measured all of the float valves and they all had a different measurement; 16.88 mm, 16.92 mm, 17.02 mm and 17.2 mm. I measured from the tips to the point where my calipers touched without depressing the springs.

Video - https://youtu.be/aZNbfEnRrsM