1981 GL1100 Carburetor and Starter issues

[56michael]

I had a curious issue with my 81 GL1100 back in 2016, when I was 1st restoring and riding it that summer.

1) I had already done a full carb overhaul, but sometimes the LH carbs would flood the LH cylinders after sitting with the motor off. This means draining the oil after purging the LH cylinders, and a fresh oil changed when this happens, which is very annoying, at the very least. The GL1100 carbs don't have bowl overflow pipes, so if float level isn't perfect, it can do this even without the fuel pump running, if the fuel in the tank is higher than the carbs. Since I am in the habit of keeping my bikes topped off, this is virtually a given for me unless I am moving down the road, lol! I did pull the carbs a 3rd time to get my floats as near-perfect as possible, but I still don't trust the lack-of-overflow-pipe design.
Soultion: I keep the Petcock OFF until I get the motor started, and I always shut the petcock OFF before killing the motor. Sometimes I even let the bike run another 30-60 seconds after petcock shutoff, just to use some of the fuel still in between the petcock and the carbs.

2) Even though my petcock did not leak fuel in any position, and did stop flow in the "off" position, I discovered it DID have an AIR leak where is mounts to the tank surface. I was having fuel flow issues while riding, and though I heard a tiny "whistle sound" somewhere, when my fuel level was 3/4 or less. Well, it turned out that 3/4 tank height is roughly where the petcock mounts on the outside, hmmmm. Sure enough, the petcock base was a teensy bit warped, and the new seal there still had an air leak issue. I planed the petcock face true-flat & cleaned the tank surface there to smoothe bare metal, then re-installed the new petcock seals, and the air leak, fuel supply issue, & whistle sound, were all gone!

Maybe these 2 items will be helpful, but even the most experienced people I talked to had never heard of the #2 issue, so that I had to figure out on my own.

 

[56michael]

Thanks, my petcock was leaking when I got the bike. When it was in the off position it still l wouldn’t shut off. Replaced it already. Good idea though to keep it off till the engine starts.

 

[56michael]

Put the carbs back together after cleaning the idle jets last night also double checked the float height and set the pilot screws back to 1 1/4 turns out. Installed them morning got everything hooked back up to the air box and installed the air cleaned. Turned on the petcock pulled out the choke and fired right up. Let it run for a bit, running very smooth around 3000 rpm. Started to turn down the idle stop screw to get it to slow down and could only get it down to 1500 rpm. Haven’t touched the pilot screws yet. Let it warm up good and shut it off. Only got the idle rpm down to 1500.

 

[mcgovern61]

Might not be able to idle down if the cabs are not synced. Also, my ‘82 carbs idled best at 1050 RPM.

 

[56michael]

Synced with the vacuum gauges? I was going to get a set of them. Which ones do you recommend? I see they sell a few different ones on Amazon.
Cleaning the idle jets sure made it run smoother than it was before. Lesson learned, thanks again.

 

[StraightWings]

Couple notes to the cleaning of the jets/carbs.
1) Never use a wire (even though I love guitar strings) to even remotely touch a carb jet: you will distort them via scratches at the least, at the worst totally ruin them.
2) Good but gentler carb cleaner: Honda Compression Cylinder Cleaner. It is inexpensive, saves buying a gallon of commercial cleaner. I've done the carbs on my Valk 3 times (that's 18 carbs) with one can, while trying to get them the way I want them (which, BTW, I finally did).
Done '75, '78, '83, '92-5-6 and other years GL's with it. Jets soaked overnight will blow out clean almost every time, and for sure on the second go-round. When your carbs are stripped, use it to spray into the carb body, then hit all orifices with compressed air same thing as the jets. REMOVE vacuums (throttle Valves) and other rubber/plastic FIRST. It may not ruin o-rings overnight, but don't take the chance, and it definitely will waste your diaphragms overnight. After you have blown the passages, spray a little more Honda cleaner into the top of an orifice, watch for the outlet of the orifice you are working on while hitting it with air to ensure you see cleaner spurting out: if so you have a clean passage. (You'll also learn where those tricky little passages exit to.)

3) Throw the 80-81-82 carbs out the window and get a set of '83's. Better/easier for adjusting.

4) Use Seafoam often: you'll never have to touch the carbs until you have worn them completely out. Certainly use over the winter or for storage of 2 months or longer, every time, and about 4 oz to a tank, ensuring it has mixed properly with the fuel, and reached THROUGH carbs: run the engine until the fan comes on a couple times over the winter.

Hope you got that problem with the idles sorted. Ride safe.

 

[56michael]

Thank you for all your information. I’ll take all the advice I can get. Running way better now but still idling around 1500 rpm. Do you think I should try opening up the pilot screws more?

 

[mcgovern61]

I assume you might not have bench synced the carbs? That is a procedure where you set all of your butterfly's at the same place before putting back on the bike. (I should have mentioned the procedure before this. Tough getting old.)

Bench sync by looking into the carb barrel, close the butterfly for that carb all the way and turn the sync screw until the small pilot hole is visible. Once on the bike, run the engine to warm up before doing an actual sync of the carbs. I use this set of gauges:

 

[56michael]

I did not bench sync the carbs. Looks like you can get that set of gauges on Amazon for $72. Since I have another gold wing that I haven’t even started on I think I’ll get a set. So should I leave the pilot screws alone and sync the carbs with the gauges first?

 

[mcgovern61]

Yes. BTW, when you use this gauge set, be sure to calibrate the gauges to the #3 carb first. Hook up the first gauge to #3. With the engine running, check where it is set. Set the gauge to settle on a single line (will not be zero). The gauge is calibrated by removing the plastic cover (unscrews) and turning the set screw on the dial face (tiny screw). Be careful to not put much pressure down on the screw while turning or it will throw off the calibration. Then, one by one hook each gauge one at a time to #3 and set the gauge needle to the same line. That way, you know every gauge is calibrated to the #3 carb. #3 carb is not adjustable and is the carb you use as the reference point.

 

[56michael]

Gotcha!! Thanks. I’ll keep you posted.

 

[AZgl1800]

Be sure that your "Set all 4 gauges to Zero" before starting the engine.
They have a small set screw that will move the indicator with Zero Vacuum.

.

 

[Old Fogey]

Here's my way of bench syncing the carbs. This way there is no chance of damaging the delicate edge of the butterflies.
http://wingovations.com/synchronising-the-carburettors/4590612876

 

[mcgovern61]

I like that procedure!

 

[kerryb]

I put a homemade (crude) gear on the end of my air mixture screws so I can adjust them by pushing with a flat blade screwdriver. Paint one half of the gear dark color to keep track of # of turns. Not sure it's worth all the effort but I don't need a special tool anymore. Store-bought gear was too big to get the bowls back on so I cut the teeth off for clearance. Homemade gear allowed me to control the size.

 

[kerryb]

I also prove that my float valves are shutting off by bench testing them for float level with the clear-tube method. Also just determined the carbs on current project need to come off for cleaning and checking after filling 2 right side cylinders with fuel (hydro-locked) because the floats didn't seal up. I hope they don't need replacing because they are so damned expensive at $40 each from the dealer. Floats pictured aren't sealing so the fuel level is above the carb bowl seam.

 

[56michael]

Looking for 5.8 x 2.0mm O- Rings for the main circuit cross tubes on my GL1100 Carburetor. Randakks includes them with their full carb rebuild kit but I only need these 4 rings. They do not sell them alone. Anyone know where I could find them?

 

[56michael]

They sell 5.8 x 1.9mm alone and they told me they “might” work..

 

[56michael]

After cleaning the idle jets and replacing the O-rings on the fuel tubes between the carburetors, double checked the float height and did a careful bench sync I reinstalled the carbs.
Fired right up and it idled really nice. Set the rpm to just under 1,000 with the idle stop screw and let it warm up. No gas leaks from the carbs!!!! No steam from the exhaust. Shut it off and waited a few minutes then started it back up, still ran nice BUT!! White steam started billowing out of the left side exhaust. Shut it off and pulled all the plugs. All were dry except #4 very wet. So my oil looks like it has antifreeze in it, steam coming out of left side exhaust and a wet plug. Head Gasket? I’m thinking the steam didn’t start until the thermostat open up and was circulating into the head. Any thoughts?


Before my son gave me the bike he said him and his father in law had got it running rode it and all the coolant leaked out of a loose hose and the temp gauge went to the top and overheated. I know this can warp a head or ruin a head gasket. New head gaskets look like something can handle. Any thoughts?

 

[85goldwing]

Do a hot compression test on the cylinders. Look for differences between the cylinders. You can also look for bubbles at the radiator cap as the bike comes up to operating temp.