Just rebuilt my carbs

[Guest]

I rebuilt my carbs because it had sat awhile when I got it. 1984 gl1200I. Well before I rebuilt them it ran ok. I never had to choke it and it always fired up. But used alot of gas. 1 tank in 90 miles. I got 4 new kits and put them in. Now I have to choke it to keep it running on start up. And she has no accel till you get to a higher rpm. She pops though the air cleaner too. Now if I give just a touch of choke, she takes off like a raped ape! The pilot screws are turned almost all the way it too. I kept looking threw my Clymer book and thought the vac routing was wrong. It's not, but I noticed I don't have a PCV and I also found 2 ports open to atmosphere! In the Clymer book it is pg. 145 fig.14 item. 32 = Air vent joint pipe. I can't find out if they need to be open, closed or have something hooked to it. I wouldn't think they would be open and draw in unfiltered air. I have posted on 2 other goldwing sites but havn't got much help. Can anyone tell me about these air vents and if I have to have the PCV?
Thanks.
In the pic the air vent is between the carbs right below the choke rod. It is the same on the other bank as well.

OK... The pic says it uploaded but I don't see it!

[Guest]

I just completed a rebuild myself and as best I can tell, looking at the diagrams, nothing is supposed to be connected there. When I removed my carbs, there was nothing connected, and I reinstalled them the same way and she runs fine. If your pilot jet is turned almost all the way in as you said, then you're probably running too lean (too much air and not enough gas). Try backing each pilot out (counter clockwise) 1/2 a turn or so and see if that does the trick. When I did my rebuild, all of mine were set from factory at 2 1/4 turns out.

[Guest]

Hi Starfleet.
I just did my first carb rebuild in Aug. I believe what you are looking at are the gas overflow tubes. If your float valves don't close it will pump gas out of these tubes and onto the top of the engine(don't ask me how I know :oops: )

Tug

[Harry Slimm]

Nothing connected there. I had same question. Found answer buried in earlier posting (way earlier).

Harry %%-

[bs175dths]

1 tank in 90 miles, that’s approx. 5.5 gallons in 90 miles, or 16.364 mpg. That’s the pits!

You got 4 new kits and put them in. What kind of kits did you put in?
Randakk's carb kits are supposed to be awesome and the only ones I would trust: <!-- m --><a class="postlink" href="http://www.randakks.com/Carb%20Parts.htm#9B">http://www.randakks.com/Carb%20Parts.htm#9B</a><!-- m --> Everything you need to service the GL1200 ...

Just a reminder, these bikes do not have a choke circuit in the traditional sense. These do not restrict the amount of AIR going in (choke), but actually increase the amount of GAS going in (enriches), achieving the same end result. That helps to explain why the engine takes off like a raped ape when the choke lever is applied. Add to this the fact that the bike is sluggish until a higher rpm is achieved, indicates the slow speed circuit of the carburetors is not functioning as it was designed. The idle jets in these bikes are very small and it does not take much to get them restricted or blocked. I have read where some aftermarket fuel filters will pass particles large enough to obstruct the idle jets causing a problem as you have described. This is a situation where an additive called Seafoam is added to the gas. It helps dissolve and pass these tiny particles and helps to keep jets clean and clear.

The pilot jet setting is completely wrong. I believe the setting is 2 ¼ turns out from seat, and seat is a feeling of slight resistance when closing the pilot screw. Check this setting before taking it as gospel.

The vents you refer to appear to go to the slow air cut-off valve. There are a total of two valves on the underside of non-California carb sets, and three on the California carb sets. The non-California sets have a purge control valve, an anti-after burn valve and a Slow Air Cut-off Valve. Each bank of carbs are supposed to go to separate ports on the SACV, then the valve goes to a ‘t’ fitting between the No. 4 intake and the anti-after burn valve. A suggestion is to scour E-Bay searching for carbs which include clear shots of the underside of non-California carbs. This may answer your questions about routing.

THESE ARE NOT THE FLOAT BOWL OVERFLOW TUBES. The overflow tubes are on the underside of each float bowl.

All I can suggest is pulling the carbs again and rechecking the installation of the carb kits. Also look to make sure the throttle needle diaphragms are installed correctly. If these are not installed correctly or if the diaphragms are cut or torn, the slides will not slide up with increased engine demand. While in there, make sure the slides glide up and down with little resistance. Clean with gas (only and in a well ventilated area) as necessary. Replace intake o-rings and ALL vacuum lines if they are questionable. The butterflies on the carbs should ‘snap’ shut and the choke valves (one for each carb) should operate equally and completely (completely open or completely shut), lubricate and work these little valves until they work in unison. Change the fuel filter and EVEN IF THE AIR FILTER LOOKS GOOD, change it! It may look good but can be dirty enough to cause a rich situation.

Good luck.

Any other questions, comments or concerns, drop them off here. Tons of information and friendly help awaits.

-Ride On ~O)

[Guest]

Thanks for the info! In case I didn't put it in here, the guy sent me the wrong main jets. I got the new jets and put them in. The kits are KEYSTER CARB KIT. When I put the new jets in I recleaned the carbs. I checked all the jets and passageways. I sprayed and blew though all of them. Every jet is clear and passageway have no restrictions. I warmed the engine up and set the sync, then set the idle drop. "The correct presetting is 3 and 1/2 turns out." After seting and rechecking everything I took it our on the road. I had to open the pilot screws a 1/2 turn more but she ran ok. The next morning I started it up to ride to work. The temp was about 55*. It is about 7 miles to work. I let it run for 10 min's while I got ready. Took the choke off and started out. She fell flat on her face!!!! No power, starveing for fuel. I opened the choke and she took off. I had to ride with the choke on "1/4 on" all the way to work. When I left work it was around 70* and I still had to ride with the choke on. But only for a few miles. I rechecked the sync and Idle drop last Wednesday. Only had to make minor changes. She ran good all the way home. Thur morning it was in the mid 50's and she ran like crap again. I am ready to shoot myself! this shouldn't be that hard. I can set an other bike or car fine. My last bike was a peice of cake. She ran good when I first got her, but I could see crap coming out the float bowl drains when I opend them. Thats why I rebuilt them. I didn't even have to choke her to get her started!
I am starting to wonder if there is a thermostat in her. The temp gage only goes to the first mark and she never really seems to get all that hot. The cooling fan runs alot, but I think the sensor is acting up. I have seen posts of this problem. The air coming from the fan is warm not hot. Even after sitting for 30 min's if I turn the key on the cooling fan will come on. The tubes I am saking about are the over flow tubes. I have the 48 state carbs, so no emissions or PCV. The air valve works per the test in the book and I replaced the after burn valve since it came in the kit. I checked the timing belts and marks and they are right on the money. I just have to find the plug for the crank case so I can check the timing and advance. Hope you have other Ideas!!! And thanks again for the help.....
Rick

[bs175dths]

No Shooting Rick. No smoking, no drinking, no kicking the dog (cat)

BTW, you are right, that is overflow, I was thinking the bowl drain is on the bottom.


You have many issues which need to be addressed one at a time.
The 84 Interstate is not EFI and therefore, the carburetion and cooling systems do not interact with each other.

As far as the cooling system, make sure it is full of coolant. With regards to the cooling fan on a lot and running a lot, I added a light to the dash to tell me when the fan comes on. I have it mounted on the same plane as the temperature gauge so I can see at what temp. the fan is turning on and how often. Something to think about. The sensor is just a thermo switch which operates the cooling fan. The thermostat may be stuck in an open position, allowing the water to circulate too much and not give it a chance to get hot. Your thermo switch may be defective because if after riding the bike a decent amount, the air coming off the radiator is only warm, the water should not be hot enough to trigger the fan to come on. Again, check the coolant level and make sure it is at a correct level.

As far as the carbs, I am leaning (no pun intended) toward the idle circuit not functioning proper. It is not the fuel delivery, (fuel pump output, fuel filter clogged, collapsed fuel line) because introducing the choke (enrichment) caused the engine to perform. Try Seafoam and ride while you get over the fact that the carbs came out yet again. Check the fuel filter and make sure it is clean and not dirty. Dirty means there is stuff in the gas tank and the filter may be passing it onto the carbs.

See if you can narrow the lack of performance to the individual cylinders.
There are several things which can happen off of idle:
A coil can misfire due to cracks in the coil body, dirty or loose electrical connections
A spark plug can work intermittently
A high tension lead can work intermittently
The ignition trigger may be working intermittently (lease are located at the back of the engine on an ’84)
If you find one or two cylinders not working, try to get the problem to move by moving the spark plugs or changing the high tension leads. Take good notes!

The throttle needle on these bikes are operated with a difference of atmospheric pressure. Air is trapped in the top of each carburetor and as the engine speed increases, the engine breaths in more air. The faster the air passes through the carburetor body, the greater the difference in pressure with the air trapped above the throttle needle. It is this difference of pressure which caused the throttle needle to rise, thus allowing more fuel to be drawn out of the bowl and into the fast moving air passing through the carburetor body. Since this needle is tapered, the hole for fuel to pass, gets larger, thus causing the engine to increase in speed, thus causing a greater difference in pressure, thus raising the needle and so on.
The air in the top must be sealed with the diaphragm seated correctly. If there is a leak (tear, cut or not seated) a difference in pressure will not occur. Aftermarket chrome caps have been linked to a problem similar to yours.
The throttle needle needs to glide without restriction. If the throttle needle does not rise as the engine demands, the fuel will not pass as needed from the bowl and will give the effect of fuel starvation. Deposits on the plastic throttle needle piston, or on the cylinder where the piston slides, will cause a restriction or hesitation giving the effect of fuel starvation and engine hesitation. Check these throttle needle pistons and cylinders for deposits. Clean only with gas, as necessary, in a well ventilated area. I would clean them off and then continue to rub, trying to give both surfaces a ‘polished’ surface. Reassemble and check for smooth operation. I used a plastic rod inserted into each carburetor, raising the throttle needle piston, then quickly withdrawing the rod, wanting the piston to ‘snap’ shut.
There is a spring under the cap to force the throttle needle down when engine speed decreases. It needs to be seated properly in the piston and in the top or it will be compressed, making it harder to let the throttle needle rise.

My bike sat for two years. Once I got her started, she had similar symptoms as yours. At one point she could only achieve 64 mph. I ended up going into the carbs a total of eight times before she ran as she should. The limited speed was due to these throttle needles not sliding smoothly due to deposits left on the piston and the cylinder walls. She has power now.

I kept a diary of the problems I saw and the attempts of correcting these problems. I found it helpful in approaching the problems methodically and helping me identify things I overlooked.

Good Luck, enjoy the weekend and keep us posted.

-Ride On ~O)