Not starting! Mystery

Azrider04 · Oct 20, 2024

Hi everyone,
Just picked up this beautiful ‘04 FJR1300 last week. No issues with it before.

It had some corrosion in the tank so I took it off and lined it with POR15, I also changed the fuel strainer on the pump with a generic one from autozone. And now it doesn’t start. It will run on starting fluid but without it it kind of sputters and won’t stay running. I have verified the pump is working and that I have fuel flow to the fuel rail.

I feel like it’s something obvious! Any help would be appreciated. Thanks

Here is a video of the issue:

Here is a video of it running before I touched anything:

RossKean · Oct 20, 2024

Are all four header pipes the same temperature (or at least close) while it is running badly. First thing I might look for is a plug wire that isn't making good contact. With the cruddy tank, there is a possibility that your fuel injectors got messed up.
Couple of things to think about anyway...

Good luck - and WELCOME.

Azrider04 · Oct 21, 2024

I checked the header and all pipes were equally warm. I pulled the injectors and all of them are functioning.

Next thing I’ll try is to throw a fuel pressure gauge on there and see if the pump is creating enough pressure. That’s the only other thing I could imagine going bad.

SkooterG · Oct 21, 2024

Hopefully the POR15 didn't screw something up?

waynevb · Oct 21, 2024

Check the fuel pump is seating correctly. If the injector line doesn't get enough pressure, the bike will be hard to start and will stall unless you blip the throttle.

I had this problem after I replaced the fuel tank and a local bike shop identified the problem.

SkooterG · Oct 21, 2024

waynevb said:
Check the fuel pump is seating correctly.

Can you provide more detail? I am having trouble picturing what you mean.

waynevb · Oct 21, 2024

SkooterG said:
Can you provide more detail? I am having trouble picturing what you mean.

When separating the pump housing body, there are several latching tabs that all have to be released at the same time.

The o-ring that seals where the fuel pump assembly mates to the tank. If the old one has been compressed for a long time it may not reseal.

waynevb · Oct 21, 2024

SkooterG said:
Can you provide more detail? I am having trouble picturing what you mean.

The attached photo shows the various seals (non-OEM). I don't have an original to reference. However, the one labelled sealing rubber should have an equivalent. When my bike had this problem, the local bike shop fixed it and they said that the pump wasn't seated correctly and the fuel pressure was too low.

SkooterG · Oct 23, 2024

Gotcha. I understand now. I have had FJR fuel pumps of all generations out and disassembled many times but wasn't sure what you were talking about. Btw, I have never had an issue with the gasket sealing the pump against the tank. Even on old 2004 FJRs. Not that it couldn't happen, but not very likely imho.

SkooterG · Oct 23, 2024

That is odd what the dealer said about it not being seated correctly and fuel pressure to low. That just doesn't make sense to me.

That diagram you posted obviously is not an FJR fuel pump. FJR's looks different. I am not sure if it even has that sealing rubber. Very rare, but I have seen where the fuel pressure regulator has gone bad. Not a part available from Yamaha, but someone sourced one and fixed their problem. That was on a 2013 iirc.

SkooterG · Oct 23, 2024

Azrider04 - Where in AZ are you located?

waynevb · Oct 23, 2024

SkooterG said:
Gotcha. I understand now. I have had FJR fuel pumps of all generations out and disassembled many times but wasn't sure what you were talking about. Btw, I have never had an issue with the gasket sealing the pump against the tank. Even on old 2004 FJRs. Not that it couldn't happen, but not very likely imho.

My problem started when my bike fell over and the fuel tank was massively dented. I sourced a used tank and had to remove the fuel pump/filter/float assembly into the replacement tank.

The bike would start but wouldn't run unless I constantly blipped the throttle. I went down a few blind alleys with internet theories, such as, the bike needs to go through a full cycle of start, warm up, run to working temp. blah, blah.

As a result of trying to run this cycle, the mufflers got blued through excess heat (weak mixture). So I have up and had the bike towed to a recommended shop. They said that the fuel pump. O-ring wasn't sealing and the injector lines weren't gerring up to pressure. Unfortuntately that's all I know.

Since that time the bike has covered another 25,000 Kms without a hiccup. Just oil changes and fluids flushed and coolant changed.

SkooterG · Oct 23, 2024

waynevb said:
My problem started when my bike fell over and the fuel tank was massively dented. I sourced a used tank and had to remove the fuel pump/filter/float assembly into the replacement tank.

The bike would start but wouldn't run unless I constantly blipped the throttle. I went down a few blind alleys with internet theories, such as, the bike needs to go through a full cycle of start, warm up, run to working temp. blah, blah.

As a result of trying to run this cycle, the mufflers got blued through excess heat (weak mixture). So I have up and had the bike towed to a recommended shop. They said that the fuel pump. O-ring wasn't sealing and the injector lines weren't gerring up to pressure. Unfortuntately that's all I know.

Since that time the bike has covered another 25,000 Kms without a hiccup. Just oil changes and fluids flushed and coolant changed.

Interesting. What year? Gen I fuel pumps have a return line that does have a small O-ring within the fuel pump that ages and goes bad. I replaced one once as have others. But I think when that O-ring goes bad the FJR still runs but that it causes a leak on the return line fitting at the bottom of the fuel pump outside the tank.

SkooterG · Oct 23, 2024

Here's a thread from one of the other sandboxes. It details the issue with the Gen I return line O-ring. Also has some photos of the FJR fuel pump.

https://www.fjrowners.com/threads/fuel-leak.153544/#replies

waynevb · Oct 23, 2024

Waiting patiently for the OP to check fuel pressure.........

SkooterG · Oct 23, 2024

I am wondering where in AZ he is? He can always come by mi casa. I can loan him an '04 tank with an operating fuel pump just in case he wants to eliminate any other possibility.

waynevb · Oct 23, 2024

SkooterG said:
Interesting. What year? Gen I fuel pumps have a return line that does have a small O-ring within the fuel pump that ages and goes bad. I replaced one once as have others. But I think when that O-ring goes bad the FJR still runs but that it causes a leak on the return line fitting at the bottom of the fuel pump outside the tank.

Edit:

My bike is a gen 1. Australian supplied model. Late 2004 with ABS.

Azrider04 · Oct 23, 2024

Hello everyone, thanks for bearing with me.

I checked the fuel pressure and it was reading 0 psi even though when I had flow when the line was disconnected.

Waynevb you are the G.O.A.T!!! I checked the pump and sure enough one of those Orings that sit between the housing was not sealing. Got that fixed and she starts up perfect now!

Thanks you guys for the help!

SkooterG · Oct 23, 2024

Azrider04 said:
Hello everyone, thanks for bearing with me.

I checked the fuel pressure and it was reading 0 psi even though when I had flow when the line was disconnected.

Waynevb you are the G.O.A.T!!! I checked the pump and sure enough one of those Orings that sit between the housing was not sealing. Got that fixed and she starts up perfect now!

Thanks you guys for the help!

Did you take a picture of the offending O-ring for future reference for others?

Azrider04 · Oct 23, 2024

I did not think to do so….

The issue oring was the one that seals the body of the fuel pump housing to the fuel outlet nipple. It’s the first one you see when taking the pump apart.

Not starting! Mystery

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