Near break down, she did it again

[slabghost]

skiri251 » Mon Jul 18, 2016 1:16 pm[/url]":3lajzgtr]

slabghost » Mon Jul 18, 2016 10:13 am[/url]":3lajzgtr]
Maybe a tether switch would be a better choice for fuel shut off?

You mean the one which is connected to rider's wrist like jet skies?

yes. :yes:

 

[skiri251]

AApple » Mon Jul 18, 2016 10:23 am[/url]":2k99u64a]
I'm not unnerstanding WHY anyone thinks this is a fuel problem? A sudden loss of fuel pressure on a carbed engine will not cause it to die immediately....

Accelerated up to 4th gear or so then suddenly engine dies.

The carb still has fuel in the bowl, and will run until the level gets low enough to start sputtering/missing, and then it will die. If this thing died suddenly, without any sputtering or such, then how could it possibly be fuel related? We're not talking aboot fuel infection here....it's a single carb set-up. Am I missing sumptin or whut? I'd think it has a more electrical gremlin issue than a fuel pump.
Also....unless the fuel bowl is leaking, why do you have to crank on it after sitting to "fill the bowl"?

That was what I wanted to ask.

After I coasted to the parking lot, the symptom was I could start the engine which died almost immediately or no torque so it died while feeding clucth to move.

I had this symptom before and that was due to loose ignition ground (electrical).
There was no sputtering. Started up but couldn't hold the rev and just died..

Regarding need for the bowl filling, I think Dan and Joe talked about it also. Fuel just slowly drains from the bowl into the fuel tank while sitting?

 

[dan filipi]

I have one of those cut offs but never felt like I could trust it to work properly so didn't install it. I should have some kind of safety just haven't decided what.

 

[slabghost]

AApple » Mon Jul 18, 2016 1:23 pm[/url]":3nid5iis]
I'm not unnerstanding WHY anyone thinks this is a fuel problem? A sudden loss of fuel pressure on a carbed engine will not cause it to die immediately....

Accelerated up to 4th gear or so then suddenly engine dies.

The carb still has fuel in the bowl, and will run until the level gets low enough to start sputtering/missing, and then it will die. If this thing died suddenly, without any sputtering or such, then how could it possibly be fuel related? We're not talking aboot fuel infection here....it's a single carb set-up. Am I missing sumptin or whut? I'd think it has a more electrical gremlin issue than a fuel pump.
Also....unless the fuel bowl is leaking, why do you have to crank on it after sitting to "fill the bowl"?

I expect you are right it is electrical but so is the bank angle sensor. Single carbs can and do get siphoned of fuel after shut down in many cases. Loss of fuel pressure or flow will go unnoticed until it "suddenly" sputters and dies. I found that out a few times when I forgot to turn on the fuel.

 

[joedrum]

its not that the bowl empties joel ....its that the line going to carb will gravity feed back to tank ...the car carbs dont really hold to much gas in bowl either ....not enought to start and keep running till more gas arrives ...at least not on hooch really ..if tank is totally full it starts right up ....

 

[skiri251]

I need to double-check but BAS only shuts off fuel pump. Not the ginition.

Kill switch and BSA kill fuel pump.
Kill switch also kills ignition.

Maybe I should test the spark again. It was under the bright sun shine and difficult to see but I believe I did not see any sparks immediately after.
I thought I was grounding the spark plug wrong way but I can try it in the garage to be sure.

 

[skiri251]

joedrum » Mon Jul 18, 2016 10:47 am[/url]":edgqv9vf]
its not that the bowl empties joel ....its that the line going to carb will gravity feed back to tank ...the car carbs dont really hold to much gas in bowl either ....not enought to start and keep running till more gas arrives ...at least not on hooch really ..if tank is totally full it starts right up ....

So is it possible for Oldwing engine to die all of a sudden w/o sputtering?

When I had clogged gas tank cap, the symptom was it dies all of a sudden followed by big bang.

Then again, the same loose ignition ground caused the same symptom sudden cut off followed by big bang, then somewhat recovered.
The frequency increased as I travel and finally reached the point where engine couldn't idle.
That was two years ago during a trip to Monterey.

Yesterday and the last year, there was no big bang. ... that means no fuel? If it's ignition and there was unburned fuel, it will ignite in the exhaust and cause the bang?

 

[joedrum]

ignition is always in play with honda set ups.....my bike with the dft tends to run perfect then just die when main tank runs out and reserve needs to be turn on

 

[skiri251]

joedrum » Mon Jul 18, 2016 10:56 am[/url]":2fk3c4fz]
ignition is always in play with honda set ups.....my bike with the dft tends to run perfect then just die when main tank runs out and reserve needs to be turn on

My Oldwing has fuel pressure gauge but I did have time to look at it when the engine died.. :head bang:
But I was at half throttle and there was no bang either.
That means more likely the fuel than ignition?

 

[skiri251]

dan filipi » Mon Jul 18, 2016 10:36 am[/url]":3ixvfkxq]
I have one of those cut offs but never felt like I could trust it to work properly so didn't install it. I should have some kind of safety just haven't decided what.

How does GL1200 w/ electric fuel pump work?
BAS for safety or nothing?

 

[mcgovern61]

It sure sound electrical to me. Last week, I was riding along on the highway and making a minor adjustment to my right side mirror after hitting a big bump and suddenly the engine shutoff (although still spinning at 3000 RPMs and dropping). Turns out, my riding glove caught the kill switch. Still moving along, I turned the switch back on and the bike took off again.

I would also check your ground wire under the faux tank and be sure it is clean and tight.

 

[skiri251]

Wait a minute..
I vaguely remember in the parking lot i looked down and noticed no fuel pressure.
I thought that's because the main switch was off but it's just a mechanical gauge so it should have had some pressure..

But then it doesn't explain why the following start attempts failed.
This time I am sure I heard the pump clicking.

 

[skiri251]

mcgovern61 » Mon Jul 18, 2016 11:09 am[/url]":19xfx78t]
It sure sound electrical to me. Last week, I was riding along on the highway and making a minor adjustment to my right side mirror after hitting a big bump and suddenly the engine shutoff (although still spinning at 3000 RPMs and dropping). Turns out, my riding glove caught the kill switch. Still moving along, I turned the switch back on and the bike took off again.

I would also check your ground wire under the faux tank and be sure it is clean and tight.

I guess I need to redo those wires under tha false tank..

 

[dan filipi]

I've found with the single carb it will cut off suddenly when out of gas just like hitting the kill switch. On the stock carbs it would sputter a bit first before dieing.

 

[slabghost]

dan filipi » Mon Jul 18, 2016 2:48 pm[/url]":2fcotoal]
I've found with the single carb it will cut off suddenly when out of gas just like hitting the kill switch. On the stock carbs it would sputter a bit first before dieing.

Makes sense. Four float bowls versus one.

 

[skiri251]

Well I did series of tests.

1. spark test
The way I grounded the plug did produce the fat spark in the garage. Hard to believe I missed it under the sun even with my aging eyes.

2. BAS test
BAS only shuts off fuel pump not ignition.

3. fuel test
I disconnected +12v to the the pump while engine was running.
Eventually the engine died. After that, any attempt to re-start the engine never started the engine even for a moment.
This is totally different from what I experienced in the parking lot yesterday.
The engine started then died yesterday. (and a year ago in the city.)

4. fuel pressure gauge test
If the pump stops, the pressure goes down to zero fairly quickly (in several seconds.)

The facts:

a. BAS only shuts off fuel pump, not the ignition.
b. Malfunctioning kill switch should totally shut off ignition. There is a relay to supply +12V to the ignition system so no intermittent ignition shutoff.

So...
These make me believe it was the ignition.
Somehow it didn't work properly and failed to produce strong sparks.

Maybe the other end of the ground (where the ground wire connects to the PCB) is not good..
I can't really say anything since the symptom occurs only once a year.

I am in no mood to re-do everything so for now Oldwing will be ridden leisurely on weekends where I have plenty of time to spare.
Any time critical stuff will be assigned to XS750.

Freeways should be avoided as much as possible but if I have to use it I should be in the right most lane so that if the engine dies I can safely coast to the shoulder..

 

[Ansimp]

Normally you would get a backfire if the ignition fails when it becomes operational again. Are you using a single carby and if so does it have a shut off solenoid on it? Make sure that all your ignition relay wiring is good and as I stated earlier you can bypass the circuit for testing if you have a 5 pin relay or use a relay mounting block.

 

[joedrum]

well i can agree it probably ignition ...mostly the stock 1100 ignition is heat sensitive and also you live in cali where its hot

 

[dan filipi]

Skiri has C5.

 

[skiri251]

Ansimp » Mon Jul 18, 2016 8:35 pm[/url]":tsueadhz]
Normally you would get a backfire if the ignition fails when it becomes operational again.

Yes. I experienced this 2 years ago when I had the first break-down. I was riding on a freeway with WOT so it was loud and clear.
But this time, it was slight down hill and I think I almost immediately closed the throttle, engaged the clutch and coasted.

Are you using a single carby and if so does it have a shut off solenoid on it?

I don't know..
The only electric connection to the carb is for the auto-choke. So I guess not.

Make sure that all your ignition relay wiring is good and as I stated earlier you can bypass the circuit for testing if you have a 5 pin relay or use a relay mounting block.

If it is a relay, I think the result would be black and white.
Either full ignition, or no ignition.
In my case, the engine started but died immediately or under load, exact same symptom when I had a bad ignition ground (2 years ago).