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1997 Goldwing GL1500 Asp jerking again under load below 2,000

5K views 52 replies 17 participants last post by  Rickf1985 
#1 ·
Hi all!

Well today was a gorgeous day so I decided to take my GL1500 out for a spin. And wouldn't you know it. The damn thing sometimes jerks or stumbles again under 2,000 RPM. I've been using non-ethanol fuel in it, and she's been great. What's strange is it didn't seem to happen until I took it off its maintenance stand.

I also noticed she doesn't want to start very easily at times. Cold and choke on first setting, it started and then died as though it didn't get enough fuel. Started it a second time and zooom she went. After warning her up, I took her out for a spin and the torque didn't seem as strong as usual. Once I got to 3rd gear, I accelerated a little harder at about 1,600 RPM and the jerks came back. Once above 2,000 RPM, she accelerated normal.

I'm noticing that if I roll the throttle to quickly, that's when she would sometimes jerk. But if I rolled the throttle a little slower, no jerking. I'm wondering if my accelerator pump might be malfunctioning.

If you all recall, I solved the problem last summer after replacing the spark plugs. I'm wondering if it's possible my float needle might be failing during shutdown and leaking fuel into the intake manifold. I say this because sometimes after shutdown, the engine smells flooded and it's difficult to start. Once you get her started, a little puff of smoke (blue) comes out of the left exhaust, and then all is clear. This only happens when the engine smells flooded. Wouldn't this also fowl out the plugs? Perhaps that was the reason why the last plugs failed.

I have a good mind to also check the coil voltage on the right side above the fan. It's a red wire connector and that was corroded last summer. It may have happened again because it's strange that this didn't happen until after I rolled the Wing off of its stand.

Any ideas guys?

Joe
 
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#2 ·
I have a good mind to also check the coil voltage on the right side above the fan. It's a red wire connector and that was corroded last summer.

Any ideas guys?

Joe
That's the connector to the kill switch & right handlebar switches which then goes to the ignition. There is another connector to the coils to the right of the air box. I thought you had an ignition problem all along. Cracked coil, bad wire or end cap. I have seen where coolant has leaked on top of the coils and corroded the connections.
 
#3 ·
Joe,
I agree with Dave. When you accelerate hard the voltage required to fire the plugs really increases. If you find you can gently roll on the throttle and the engine will run up to high RPM but if you hot the accelerator hard and it balks that can be a sign of a weak spark. Could be primary or secondary wiring issues, bad plugs, coil etc.
 
#4 ·
I re-read your earlier thread, and wonder if you ever Deleted the Fuel Petcock? (as I believe that you should)
Either it may be bad (which is common), and/or it may have a poor vacuum supply operating it (which will cause fuel starvation).


In regards that hard-starting when cold... Try opening the throttle 1/2-1 turn (prior to starting engine), then close, then start as-normal using choke.
I normally only have to do this when the temps are sub-30F... At higher temps, this method may flood the engine.
 
#10 ·
LOL You guys are a riot! No "jerking" on my GL1500, figuratively speaking. :grin3: I mean, I love my bike for sure, but not enough to "please" myself. I suppose I could set the cruise on, and that'll free up a hand. :ROFL:

The jerking happens below 2,000 RPM as it is trying to accelerate. I too am convinced that this a ignition/power issue and the plugs are probably not getting enough spark, either from a cracked coil, bad wire(s), or possibly a power source issue. I'll check all of that once I am done with the 1986 restoration. She runs anyways...just have to not accelerate so hard (1/2 throttle) under 2,000 RPM.

As for the seldom difficulty starting, as I indicated earlier, the problem happens after shut down and the bike has been sitting for about 20 minutes. I can smell fuel on the engine, and I believe the left carburetor is leaking fuel into the intake manifold because of a failed float needle. If you all recall, I mistakenly set the floats to 7mm, when they were supposed to be set to 8mm. I never corrected that yet, but that's coming before the Spring. I want to remove the carbs, replace the float needs and set them to 8mm, and while the carbs are off, I'll remove the coils (not sure how that's done on the GL1500; I do not have a manual for that bike), and check all of the wires, caps, and the coils. Hell since they will be off, I might as well replace them.

Any suggestions on a good aftermarket coil for the GL1500? I was unable to find one on EBAY except for a 1989 model. I'm not sure if the coils on an 1989 GL1500 are the same as the 1997 GL1500. And what about plugs wires? Any recommendations?

Joe
 
#17 ·
... I can smell fuel on the engine...

When the fuel petcock fails, it sometimes leaks fuel in the Overflow Tray... which perhaps is what you're smelling.


Don't make me strangle you... Just delete the darn fuel petcock, and report back:lash:
 
#24 ·
My coolant temp sensor (under the right intake manifold) for my GL1500 came in today. Does anyone have instructions on how to replace the sensor? I'm hoping this might be the cause of poor fuel mileage. I'm still going to remove the carbs (to replace the float needles) and the coils (to check for cracks and to perform an ohms test).

Has anyone ever replaced the sensor in question? If so, could you provide instructions? I do not have a book for the 1997 GL1500

Joe
 
#25 ·
As I recall, you need to remove the Right Fan Housing, then just reach in to unscrew it for replacing... probably want to drain the coolant first.




 
#26 ·
It's been a while, and I don't remember all the details, but we had to remove the tupperware from the front of the bike, the sides of the bike, and the top of the bike. You need to remove the cooling fan on the right side - it can be a chore to get it out, and back in. With the fan out of the way you can reach in and grab the sensor - we didn't have to drain the coolant, but a bit will leak out when you remove the sensor. Once you get it all back together you want to start the engine, WITHOUT TOUCHING THE THROTTLE. Let it idle until the fans come on and go off - this resets the engine computer. If you haven't drained the coolant, then some will have dropped onto the engine while you were swapping the sensor - this will generate copious amounts of steam while the engine is running; don't worry - it'll clear up!


I wish I had thought to take a bunch of photos to do a how-to article...
 
#27 ·
I don't know where to start, the temp sensor will not effect fuel mpg. If the floats are leaking you need to fix the carb's and maybe change the plug's if they show sign's that they were running rich. Check the carb diaphragms for leaks, they will cause the bike to not take gas. Expensive $200.00 for both only buy the Honda OEM. Ask how I know. After you get the bike running with the carb's fixed balance the carbs with each other. You need some kind of gauge, I bought some with fluid in them and you set one carb to the other. I could not balance them by ear or other methods. Once you do all that start looking at the coils and wire's. I think your carbs are not right and look for vacuum leaks the hose's under the carbs and the hose's from the left head. and all the other hose's. The carb's have to be right or that bike will not run right. also your going to have the fan out to replace the sensor might as well pull the other one and fix the carb's. Just my 2 cents
 
#29 ·
I don't know where to start, the temp sensor will not effect fuel mpg. If the floats are leaking you need to fix the carb's and maybe change the plug's if they show sign's that they were running rich. Check the carb diaphragms for leaks, they will cause the bike to not take gas. Expensive $200.00 for both only buy the Honda OEM. Ask how I know. After you get the bike running with the carb's fixed balance the carbs with each other. You need some kind of gauge, I bought some with fluid in them and you set one carb to the other. I could not balance them by ear or other methods. Once you do all that start looking at the coils and wire's. I think your carbs are not right and look for vacuum leaks the hose's under the carbs and the hose's from the left head. and all the other hose's. The carb's have to be right or that bike will not run right. also your going to have the fan out to replace the sensor might as well pull the other one and fix the carb's. Just my 2 cents
Fans don't need to be removed to do carb work.....!!

Plus the left fan is more difficult to remove/replace than the right fan.
 
#30 ·
DBohrer, you are right about the fans, left is much harder to get out and in. There is a bracket in the back , upper right side that if you take that bolt out it gives a little slack to get the fan back in. Thats sitting and facing the left fan. Having both fan's out makes it a little better for me. Those's pages from the manually should help him change that sensor. I replaced my jet's in the carb's with what was in a kit the main jets were 48's the bike would not accelerate and would bog down if I rolled the throttle on to fast. I put the stock 58 jet's back in and replaced the diaphragms that was over 2 years ago and no problems. I get 35 to 39 mpg depends on where I'm going. I do think different years had different size main jets because of smog law's. I have found if I try to fix to many things at once I don't have much luck. That's what I was trying to say, get the carb's right and vacuum lines back where they go and the bike should run. If not look at the spark. Works for me but I just guessing.
 
#31 ·
GoldwingA1500
Joe:

I have a set of coils with the spark plug wires for an 88 Wing. Coils are the same as 97 but only some wires are the same according to part numbers, but still might work okay. The wires on 88 could be shorter or longer..... i don't know.

If you need coils let me know. Wires will be attached so if they are the right lengths or not they will be included anyhow. $20 plus shipping.
 
#33 ·
Great! Hold on to the coils for me in case I need them. As long as the coils are the same, then that'll be just snappy. As for the wires, I'll will order new wires and end-caps and assemble that myself. Right now, the coil is on hold as I may have found the problem.

Joe
 
#35 ·
I wouldn't recommend deleting the petcock, except perhaps for a test...

Petcock is rebuildable and parts still available... Or you could substitute with electric petcock valve, somebody posted a link to one, used in RV Aux Generator fuel systems...
 
#36 ·
I like the electric petcock idea, but I'll stick with stock. I haven't pulled the valve off yet (might do that today). But the way it's acting, I suspect the metal seal bushing is likely stuck and unable to slide in or out. It passes the vacuum pull test without losing vacuum pressure. But the valve itself is not shutting off the fuel when vacuum pressure is released. And so I suspect it is also not allowing full fuel flow as well, but only enough to allow the engine to run. Naturally under high RPM loads, more fuel is pulled through the valve. But below 2,000 RPM, I think their might be a minor starvation issue. I read of another GL1500 owner who had the same symptoms as mine; jerks under 2,000 RPM and would often have a gassy smell after shutdown. Turns out it was his petcock. Even so, I still think I have a carb-float needle issue on the left carb since it appears to be the left intake manifold that sometimes gets flooded after shutdown. And I still want to remove the coils and wires to ohms test them, and inspect the coils for possible cracks. We are headed to D.C. in May for a Veterans rally so I want to make sure the bike is 100%.

Joe
 
#42 ·
I took the valve apart and found the problem with the fuel flow not shutting off after shutdown. The forward seal was stuck (likely from time) and would not move enough to fully open or fully close. I ordered the kit this morning, but it turns out the rubbers were just fine; the rear larger seal was a little oily or fuel soaked, but I cleaned it off. I'll go ahead and replace it when the kit comes in.

I also noticed that the little air hole on the bottom was clogged up from corrosion. So I cleaned and air-blew it dry. The valve works like a charm now. Start the bike and then disconnect the vacuum line (plugging it of course), and within about 2 to 3 minutes, the carbs run out of fuel and the engine shuts down. Re-insert the vacuum line and fuel flows as it should.

But now I know without any doubt that the carb float on the left side is not closing. I replaced the fuel filter and now that the fuel is flowing well to the carbs, it only takes a few minutes of idling and the engine begins to chug and want to stall. Gas it a few times and the exhaust smells like raw fuel. So the carbs will have to come off.

Now I'm convinced that my jerking issue is fuel/spark related. The left carb is dumping too much fuel from a failed float needle, and fowling out the plugs (possibly). Whether the plugs are firing sufficiently or not, it is clear by the way it behaves that the engine is running too rich, which would explain the 28mpg that I'm getting. Once you get going down the road, the rich condition is being blown out the pipe and seems to run normal; especially well above 2,500 RPM's. Come to a stop light and she idles perfect for about 2 minutes, then starts chugging again from too much gas.

So, next week my friend and I will remove the carbs and I will rebuild them, change the float needles and needle seats, replace the jets with the correct ones (someone put larger main-jets in the carbs), and see how it does. However, with the carbs out, I will also remove the coils and wires to ohms test them and also inspect the coils for damage/cracks.

I'm certain that this will solve the jerking problem.

On a side note, when I had the carbs out last year, I noticed that one of the CV cups was scratched/chaffed. Wouldn't this cause a drivability issue if the cup was sticking?

Joe
 
#43 ·
Update:

Carbs are removed and I found a few jets slightly clogged, but nothing major. I have a rebuild kit with new jets, seals, and idle mixture screws. So all will be good.

Inspection revealed my suspicions that the left carb float needle was not cutting fuel flow (flooding) even with engine shut off. Now that my auto-fuel petcock is functioning, the fuel that remains in the fuel hose after shutdown drains into the left intake manifold. When the carbs were removed, you could visually see a puddle of fuel in the left intake manifold; not a severe puddle, but enough to know that the float needle was failing. I measured the float height and it is waaaay off at about 6mm. If you recall, I set them at 7mm in error, but will correct it to 8mm. The right carb float needle was just shy of 7mm, but it was sealing.

The left carb also had torn seals around the jets, so I wonder if fuel may have been seeping in there as well; I'm not sure if that would make a difference or not. At any rate, the rebuild kit comes with new seals.

I performed a primary and secondary ohms check of all the coils, wires, and wire-caps, and all appear to be good. I haven't yet checked for proper voltage levels so I will be doing that next to ensure that each of the coils is receiving proper voltage.

At this point, it appears the jerking was a fuel-fowl issue from the left 3 cylinders due to a failed float needle and improper float height. I will be cleaning the carbs, and installing new jets and idle screws, with new seals. So that should solve the flooding issue after shutdown.

With regards to ignition, it's possible I may have a problem with the center coil, but more testing will be needed to confirm any voltage or ohms issues. Right now, the primary ohms test of 20 to 26 ohms is passing on all 3 circuits. I measured approximately 23.5 ohms on the right coil, 22.3 ohms on the middle coil, and 24.6 ohms on the left coil, so all appear to show proper primary ohms resistance values. However, as indicated, I will be testing for ample voltage to each of the coils since the wires on this bike appear to be corroded. Yet at this time, I believe the primary issue is carb related, and so SHOULD solve the jerking issue which I now believe is a misfire issue involved with excessive fuel.

Joe
 
#44 ·
Mission Accomplished!!!

Man she runs so smooth now and accelerates much stronger than before, and without the fuel smell I would often get. The left car float was not functioning and the float height was too short at about 5mm, although I thought I had set them at 7mm 2 years ago when all of this first began. I set both floats at 8mm.

The o-rings on the left and the right carbs were bad for the jet caps. I'm assuming this may have allowed too much fuel when not needed for both the slow and fast jets. If I understand the caps correctly, there is a fuel hole on the very bottom. The first jet to receive fuel is the slow jet (I think). The fast jet will get fuel also, but not quite as much as the slow jet during low RPM ranges and loads. When more fuel is demanded, and the RPM is much higher, sufficient fuel will travel through the jet caps to cover both the slow and the fast jets. I've never seen this kind of setup, but I assume that is how they function.

Unfortunately 2 of the left cylinder plugs are fuel fouled; they still spark but not near as strong as the other plugs. So out of curiosity I switched them out just to make sure it wasn't a coil or wire issue, and it's definitely the plugs (2 of them). I assume the very rich condition fouled them both out and so I will have to replace them AGAIN! LOL And I didn't even get 6,000 miles on those damn plugs. Seems like Honda plugs are so touchy when it comes to fuel fouling. Run them rich too long and at high speeds, and they go bye bye. Never happened to me in my truck. Then again I rarely have rich conditions.

So then, now on to the front forks wobble problem.

Thanks for all of your help guys!

Joe
 
#46 ·
...they still spark but not near as strong as the other plugs.
I assume the very rich condition fouled them both out and so I will have to replace them AGAIN!
If they are still sparking and not causing misfire I'd clean them up best you can and simply screw them back in and let the properly running engine clean them the rest of the way...
 
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