Ltd runs to rich


Information and questions on GL1200 Goldwings (1984-1987)
Post Reply
User avatar
EasyBadger
Posts: 51
Joined: Mon Oct 30, 2017 8:32 pm
Location: Cochrane, AB, Canada
Motorcycle: 1982 GL 500 I (Silvy)
1985 GL 1200 Ltd (Goldy)
1985 GL 1200 Ltd (parts bike)

Ltd runs to rich

Post by EasyBadger »



Hi everybody,

My Ltd runs to rich. Running the bike with sea foam helped a bit. The consumption went down from 7.3 to 6.6 L/100km. Today I started to clean the carbs with a carb cleaner. When I sprayed it into the left side the engine ran normal, when I sprayed it into the right the engine died.

Any thoughts?

Safe rides,
Jens



User avatar
virgilmobile
Posts: 9082
Joined: Sun Sep 19, 2010 5:39 pm
Location: Denham Springs,La.
Motorcycle: 1988 GL1500 I
Previously owned
78 GL1000
81 GL1100
82 GL1100 I
83 GL1100 I
83 GL1100 standard
84 GL 1200 I

Re: Ltd runs to rich

Post by virgilmobile »

I'd first check one easy thing.
From dead cold,start the bike..don't rev it up...try to just let it idle for 7-8 seconds and shut it down...Very lightly tap each exhaust header...A proper running engine will have equally warm exhaust pipes.
The cold one(s) are the problem area.
From this you can check the 3 needed things to make it run properly...Spark,compression and fuel mixture...
It's a process of elimination.

User avatar
Rednaxs60
Posts: 2352
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
1995 GL1500 SE CDN Edition
2012 Suzuki DL1000 VStrom
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Ltd runs to rich

Post by Rednaxs60 »

No carbs on your bike, the carb cleaner is to clean the throttle plates.

What seems to be happening is that the engine cylinder bank balance is off, and the TPS may be out of calibration as well. This will affect the fuel consumption considerably. You can tell which cylinder bank is not working as hard as the other from the spark plugs. The plugs on one side will be burning correctly, the other not.

There are two screws that affect the engine idle. The idle screw that is in the middle rear of the throttle linkage, under the fuel tank. The cylinder bank balancing screw that is under the right CFI cover. The PO might have tried to set the engine idle using the wrong adjustment screw.

The engine needs to be balanced first, idle set, then check the calibration of the TPS. You balance the engine cylinder banks, left/right, with gauges or a manometer. You cannot balance between cylinders on the same side because of the fuel injection. You cannot balance the engine cylinder banks unless you use gauges/manometer hooked up to the intake to the engine cylinders. I have both and prefer gauges. Good investment as you will use as a regular maintenance issue.

You only need two gauges and when you do the balance of the cylinder banks, use the front or rear cylinders, don't mix and match a front left against a rear right. You can the change and check the balance with the other two cylinders. 4 gauges are better and nice to have when doing this as you get to see how each cylinder is affected when you set the cylinder bank balance.

After you have done this, increase the idle speed with the idle set screw, then spray carb cleaner into each cylinder, the engine will stay running, may bog down a bit. Spray into the cylinder(s) until you hear the engine RPM start to decrease, stop spraying, allow the engine RPM to increase then spray again.

After you spray clean the throttle plates, check the engine balance again, set the idle and check the TPS calibration.

You will notice a difference.

After this virgilmobile has provided good guidance.

Once you get this done, check the exhaust header temperatures with one of those small temperature guns. You should see that the temperatures are fairly close on each side, won't be exactly the same it is a 34 year old bike. Check the compression to get a baseline, can't change what it is unless you want to do some work.

Just back from a two up tour of the north end of Vancouver Island, some 1500 Kms. Averaged 17 to 18 Kms per litre on the highway. Your bike should be able to get similar.

Good luck.

Cheers
"When you write the story of your life, don't let anyone else hold the pen"

Ernest

User avatar
paneled
Posts: 73
Joined: Thu Sep 17, 2015 8:33 am
Location: kansas city mo
Motorcycle: 1986 Goldwing 1200 aspencade sei

Re: Ltd runs to rich

Post by paneled »

There are two sensors above and in front of the air cleaner
cant remember what honda calls them, they are sensors that
detect manifold pressure or vacuum, the hoses to them tend
to dry rot and leak vacuum causing the engine to run richer than
it should, my sei had similar issues. I replaced the vacuum lines
from the engine to both of these sensors and all is well.
86 aspy sei
54 chevy panel truck
68 chevy van
69 chevy van
64 chevy van

User avatar
Rednaxs60
Posts: 2352
Joined: Wed Nov 18, 2015 12:44 pm
Location: Victoria, British Columbia, Canada
Motorcycle: 1985 GL1200 LTD
1995 GL1500 SE CDN Edition
2012 Suzuki DL1000 VStrom
2008 GL1800 (sold)
Ontario 1985 GL1200 LTD (sold)

Re: Ltd runs to rich

Post by Rednaxs60 »

These sensors are the PBl/PBr (manifold pressure sensors).
"When you write the story of your life, don't let anyone else hold the pen"

Ernest

User avatar
EasyBadger
Posts: 51
Joined: Mon Oct 30, 2017 8:32 pm
Location: Cochrane, AB, Canada
Motorcycle: 1982 GL 500 I (Silvy)
1985 GL 1200 Ltd (Goldy)
1985 GL 1200 Ltd (parts bike)

Re: Ltd runs to rich

Post by EasyBadger »

For now, I can only dream of 17 to 18 km/L. I checked the compression when I got the bike and replaced the spark plugs. It was between 125 and 130 psi on all 4 cylinder. At the moment I'm looking for somebody with a balancing tool. If I have to make my own, which kind of gauges do I need (range). I also checked maintenance books, but the pictures are very unclear where and how to connect the gauges.

Thanks for the help,
Jens

User avatar
EasyBadger
Posts: 51
Joined: Mon Oct 30, 2017 8:32 pm
Location: Cochrane, AB, Canada
Motorcycle: 1982 GL 500 I (Silvy)
1985 GL 1200 Ltd (Goldy)
1985 GL 1200 Ltd (parts bike)

Re: Ltd runs to rich

Post by EasyBadger »

Today I finally got 2 vacuum gauges. When I checked for the sensors, I found the lines already have the gauge connection installed. Just take off the plug and you can push in the gauge. The hose to the PBl came off at the t-piece. When I reconnected the hose the engine sounded better. After synchronizing the throttle valves the engine sounded even more better. As soon as the rain stops in the next days, I'll take the bike out for a test drive. On Saturday want to go on a group ride with the VJMC and the weater forcast looks great. Let's see how the mileage is now.

Safe rides,
Jens

User avatar
EasyBadger
Posts: 51
Joined: Mon Oct 30, 2017 8:32 pm
Location: Cochrane, AB, Canada
Motorcycle: 1982 GL 500 I (Silvy)
1985 GL 1200 Ltd (Goldy)
1985 GL 1200 Ltd (parts bike)

Re: Ltd runs to rich

Post by EasyBadger »

What a great day for a ride. We did a 500 km roundtrip today. After doing all the adjustments at the bike I was curious to find how it is running now. It was a success. The average is now around 42 mpg or 5.6 L/100km with 2 up. Before it was between 6.6 and 7.3 L/ 100km. I'm very happy now and cannot wait to go onto the next ride.

Thanks everybody for their help.

Ride safe,
Jens



Post Reply