Turns over but no start

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Hello, I got an 06 Max. Love it!

Had a similar issue last year after sitting through the worse part of winter. After tapping on the fuel pump relay and checking all connections and talking with Sean thought maybe it was a bad relay. I tapped on fuel pump relay one more time and bike started right up, ran great all summer and fall.

Did the same thing this year after winter. The bike is garaged and covered when not in use. The bike is well maintained and have found no corrosion issues.

Going by my previous issue I got a used fuel pump relay (can't seem to find a new one or a replacement, does anyone know where to get new?)
Replaced relay but still having same issue.

The bike turns over fine. When turning the key on you immediately hear the Vboost slide sound, then nothing. Previously you would hear the Vboost sound then 2-3 clicks from the fuel pump.
I tried the fuel reserve switch in different positions. All indicator lights are working fine. If I apply power directly to the fuel pump it works fine. The bike actually starts right up for a few seconds when I power the pump up briefly.

I have verified power to the relay. I have checked the wire from fuel pump relay connector to fuel pump connector and wire checks fine.

I have been talking with Sean, He's great. He is actually sending me some parts to swap out and see if I can figure out what is bad.
While waiting for the parts to arrive I was wondering if anyone has had a similar issue and what they might have found?

I got the parts from Sean today. It’s definitely not a bad fuel pump relay. Just installed a 3rd relay and still fuel pump not getting power past relay.

As I understand it wouldn’t be a kill switch issue?? as the bike turns over and starts for a few seconds if I put power direct to pump and put a little fuel in the carbs.
 
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Have you got a spark when it turns over?

Once you have turned the ignition on is there fuel in the float bowls?
 
The fuel pump works fine when power supplied directly
Also Sean sent a fuel pump and it was same result
You've tested by disconnecting the line to the carb and see fuel flowing into a container?
If you disconnect the fuel relay and power the pump directly, does the engine run?

When you try to turn the engine over, try spraying some volatile substance such as carb or clutch cleaner - if engine picks up, it is a carbs issue.

How long has the bike been standing since the last time it ran correctly? The pilot jets tend to get blocked after a while so the engine may fire initially for a few seconds then die.
 
sounds like fuel is not getting to the carbs so possible blocked fuel line of gummed up filter?
Is there a prize for whoever turns out to be correct :)
 
Well I don't know about a prize but I'll gladly buy you a beer.

My original post was a little lengthy and maybe not expressed right but yes I've checked all these things.
The fuel pump/filter is good
The fuel pump relay is good

When I apply power direct to fuel pump it pumps and the bike will start and run for a few seconds until that fuel is gone.

I parked it in December it was running fine. Before even trying to start this spring I replaced fuel filter, Cleaned K&N air filter did the shotgun cleaning on the carbs as I do every year.

At least on my bike when you turn on the key you hear the vboost slide sound and then a couple clicks from the fuel pump hit start and away it goes.
Now however when you turn on the key you hear the vboost sound and then nothing.

I have verified i'm getting power to the fuel pump relay and I've verified the wire from relay to pump is good.

I have concluded the fuel pump relay itself is good because I've tried two other relays from Sean with no change.

So it seems something is keeping the relay from sending power to the fuel pump.

Looking at the wiring diagram of the fuel pump relay and going by process of elimination. I don't think it has anything to do with kill switch as bike turns over and will start briefly when I direct power the pump.
I don't think it's a fuel sending unit because as I understand the fuel reserve switch will override the sending unit and power the pump.

I'm at work now and don't have the print with me but as I recall the igniter is on the fuel pump relay as well as the vboost so i'll be checking those next.

I'm a decent parts changer but not so much on the electrical side of repairs. I appreciate any and all help.
 
You've tested by disconnecting the line to the carb and see fuel flowing into a container?
If you disconnect the fuel relay and power the pump directly, does the engine run?

When you try to turn the engine over, try spraying some volatile substance such as carb or clutch cleaner - if engine picks up, it is a carbs issue.

How long has the bike been standing since the last time it ran correctly? The pilot jets tend to get blocked after a while so the engine may fire initially for a few seconds then die.
I haven't pulled the fuel line but when I apply power directly to pump it works and sends fuel to carbs. The bike will start right up and run for a few seconds until that fuel is gone.

It's been parked since December, ran fine when parked. After the winter nap I change the fuel filter and do the shotgun carb cleaning each year.

The issue seems to be something is not allowing the fuel pump relay to send power to the fuel pump. I mentioned some additional trouble shooting to come to that conclusion in my previous posts
 
You have a spark and have confirmed that the pump and relay are OK by substitution.
For the pump to work then the relay needs to get a signal from the ICU that the motor is running via the yellow wire.
My best guess is that it is a wiring issue somewhere between the ICU and pump relay.
 
You have a spark and have confirmed that the pump and relay are OK by substitution.
For the pump to work then the relay needs to get a signal from the ICU that the motor is running via the yellow wire.
My best guess is that it is a wiring issue somewhere between the ICU and pump relay.
This was going to be my guess as well. It's not getting the tach signal to prove it's running. BUT, I am not sure that it should at least run for 5 seconds when the key is first turned on.
 
Couldn't you just temporarily "hotwire" the pump from a switched/fused source and be able to ride? Then in the evening when the world is quiet, you could continue your troubleshooting.

If you do that, it might be advisable to include a bank switch if you're worried about small things like fire when the bike is dumped and the pump continues to run.

Having said that, I will confess to having converted my '78 GL1000 to electric fuel pump years ago. I didn't add the cutoff at that time vowing to do it "later". I guess I didn't specify exactly how much "later".

(Vmax-related because of the handlebar)
 

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sounds like fuel is not getting to the carbs so possible blocked fuel line of gummed up filter?
Is there a prize for whoever turns out to be correct :)
You have a spark and have confirmed that the pump and relay are OK by substitution.
For the pump to work then the relay needs to get a signal from the ICU that the motor is running via the yellow wire.
My best guess is that it is a wiring issue somewhere between the ICU and pump relay.
thank you, I’ll trace down that wire and see what I can find
 
You have a spark and have confirmed that the pump and relay are OK by substitution.
For the pump to work then the relay needs to get a signal from the ICU that the motor is running via the yellow wire.
My best guess is that it is a wiring issue somewhere between the ICU and pump relay.
Hello, Wire from tach to fuel pump relay checks ok.
I just swapped igniters and no improvement.
I’m missing something.
starting over.There’s a few black wires going into the harness. Could you tell me exactly where the black (ground) wire goes from fuel pump relay?
 
Hello, Wire from tach to fuel pump relay checks ok.
I just swapped igniters and no improvement.
I’m missing something.
starting over.There’s a few black wires going into the harness. Could you tell me exactly where the black (ground) wire goes from fuel pump relay?
Forgot to note I also swapped out tach/dash assembly with one Sean sent. So good from tach to fuel pump relay
 
Hello, Wire from tach to fuel pump relay checks ok.
.There’s a few black wires going into the harness. Could you tell me exactly where the black (ground) wire goes from fuel pump relay?

If you look at the wiring diagram (you do have one?) you will see that the yellow wire splits and goes to the tacho and ICU - you should also check that as well.

Looking at the wiring diagram again you will see that the black wire goes to the main earth point.
 

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