Fuel system diagram (v11 lemans) - what kills the fuel flow other than the obvious?

[Gmc28]

Looking to sort out what would keep Goldie (v11 lemans) from getting fuel, other than the usual culprits (petcock off, bad filter, bad pump, which all are fine).

I’m thinking this week just changing out the old fuel which has been sitting way too long will be the solution to why she won’t start.  But it’s nagging at me that she doesn’t run poorly with the old gas, something I’m familiar with, but she won’t run at all, won’t even cough/fire, and the plugs are dry.  Is there something in the fuel injection setup that will just cause fuel to not be introduced to the throttle bodies?  Fuel injection on bikes for me has always been “works good, lasts a long time”, so I’ve got nothing to draw on there in my personal memory banks. 

The clues for those indulging me with reading this quiz:   goldie was my sweetheart till the friend i bought it from said he’d like to buy it back.  So I parked her and bought Red, and have been riding Red ever since, so about 3-4yrs. (And no, still hasn’t bought goldie back yet :->)  Goldie went into storage mode running perfect, back then.  Then each year some new problem would come up when I’d run her.  Last go-around was the fuel pump died, so replaced that and the filter. Then she’d run, but poorly.  That was about a year ago, maybe longer.  I think i put in some fresh gas then, but thinking maybe i didn’t, or i did but that gas is now also getting old on top of the other old gas that was in her plumbing.  Fuel pump runs smooth and pushes fuel out the return line like it should (when i disconnect it).  Thinking I’ll just empty what fuel is in her using the fuel pump via the return line (partly because I’m sick of pulling that tank off), put in some fresh gas, and maybe problem solved.  

But I’d think she should at least cough/splutter a bit with that old gas?  If so, am i missing something obvious as to why she’s maybe not getting fuel?  

Will sleep on it and maybe erase this post out of embarrassment of the obvious solution which may come to me….

[Lucky Phil]

An important component of gasoline is the Aromatic "top end" without this engines often won't start at all. The top end disappears with age and especially heat. It's a waste of time troubleshooting any starting and running issue with years old fuel in the bike. Replace the fuel and the next cab off the rank is an injector clean and spray pattern check if it's been sitting around as long as you indicate and what you've previously done. You can remove the injectors and connect them to a 5 volt battery supply to hold them open and run them in a small and cheap ultrasonic jewellery cleaner which is essentially what the professionals do but you won't be able to test them for flow and spray pattern. 

 

Phil 

[Gmc28]

Thanks Phil - makes sense, just never had it be this bad.  But if there is in fact gas that old in there (I thought i freshened it up last time around, but maybe not), then the smoking gun will be easily fixed tomorrow!

Years ago someone brought me their Cagiva Gran Canyon (ducati 904) to see if i could get it running right for them.  Both times after going through all the usual stuff, which took some man-hours, i finally realized it was just old fuel.  Felt stupid, but they got a sweet running bike back.  Then I did the exact same thing again years later…..  Embarrassing. You’d think I’d learn, but, well, what can i say.   But in both cases the bikes (both Ducati 904’s) would run, just real poorly.   Maybe this gas is just older.

[pete roper]

Also, if you've tried to run it with stale gas make sure you purge the line to the injectors and then replace the spark plugs as well. If it has fired, even briefly, on the old gas it may well of fouled the old plugs to the point where under stress in the combustion chamber during compression the spark will track down the insulator rather than jumping between the electrodes and won't ignite the mixture. This is very common, especially with modern fuels.

[Gmc28]

7 hours ago, pete roper said:

Also, if you've tried to run it with stale gas make sure you purge the line to the injectors and then replace the spark plugs as well. If it has fired, even briefly, on the old gas it may well of fouled the old plugs to the point where under stress in the combustion chamber during compression the spark will track down the insulator rather than jumping between the electrodes and won't ignite the mixture. This is very common, especially with modern fuels.

Interesting.  I did check the spark the simple way, grounding it against the case, and both fired visually just fine in that little test, but perhaps as you’ve indicated not the case in the chamber.  Easy enough to address that!  Thank U Pete 

[Gmc28]

Drained old gas, put in fresh (ethanol free) gas, ran the pump to push clean fuel through and out the return line till it was clear.  New plugs.  No start. 

Will sputter with a shot of alcohol in the cylinder.  It’s just not getting fuel. 

Based on the schematic, I’m assuming that since fuel is flowing out of the return line to the tank (when i pull the line from its fitting) when the pump cycles on, that the filter (new) isn’t somehow the issue.  Or some other kink or line blockage.  Next I’ll pull a line to an injector to assure fuel is getting that far.  

As far injector issues, is there a basic, quick check?

I’ve never had actual injector issues.  Plenty of times when i thought i had injector issues on other bikes, but was always a false alarm (the smoking gun was elsewhere…. As in bad fuel, and good fuel just fixed the issue)

[docc]

Remind me what relays you have installed? True, High Current varieties (especially in Position#5)?

You have inspected and secured the nefarious, hidden spade connectors beneath the fuse block to fuse #1 and #2?

[Gmc28]

Hi Docc-

Goldie has Bosch, and early on i confirmed #5 was “clicking”, and then swapped 4 & 5 anyway just to see if anything would change. 

The nefarious #1 and 2….. not really.  Checked #2, the 30a, and the fuse and receptacle looks good/clean and unaltered in any obvious way by heat.  I suppose i need to pull the bus and check underneath?

[docc]

10 hours ago, Gmc28 said:

Hi Docc-

Goldie has Bosch, and early on i confirmed #5 was “clicking”, and then swapped 4 & 5 anyway just to see if anything would change. 

The nefarious #1 and 2….. not really.  Checked #2, the 30a, and the fuse and receptacle looks good/clean and unaltered in any obvious way by heat.  I suppose i need to pull the bus and check underneath?

Easy to check by carefully prying the fuse block up from the isolator blocks (no need to fiddle with the fasteners) and be certain those four hidden spade connectors are clean and tight (Caig DeOxit® is our friend!). They supply power from the Ignition Switch to the fuses for the fuel/ignition and ECU relays.

[audiomick]

21 hours ago, Gmc28 said:

As far injector issues, is there a basic, quick check?

I have only read about this, but it sounds easy.

Guzzidiag has a function to activate various things to see if they work. One of them, as far as I understand it, is the injectors. The function is on the page accessible from this menu next to the green mark I made on the screenshot. I can't get further than that without it being connected to a bike, but I think that should show where to find it.

EDIT: "Ansicht" is likely to be "view" in the english version, and "Aktoren" may be "actors" or something similar to that. The positon in the menu is almost certainly the same.

As far as I have read, it is as easy as screwing out the injector, connecting Guzzidiag, and activating the function. It shows you if the injectors work at all, and, assuming they do, allows you to see what the spray pattern looks like and/or see how much fuel they are letting through.

 

[Gmc28]

Thanks Audiomick…. I was looking for exactly that info on the guzzidiag info this afternoon.  

[Gmc28]

Got things lined up do work on goldie this weekend (noid light, etc), got some more good input from Gstallons, and decided to pop out to shop just for a minute after dinner.  Had a big dose of seafoam in the fuel, circulated through the pump and filter.  Cleaned up the throttle body air adjust screws, and squirted carb cleaner up in that orifice, as well as the TB sync ports.  

And, she started.  Ran like hell, wouldn’t idle on her own, but she was firing on both cylinders.  

So now we’re back to running really poorly, versus not running at all.  May or may not change what i go after next.

when she was really parked, about 4 yrs ago, she ran sweet.  That implies the usual tune-up items should be ok, and that the issue is still an “old fuel gunk” type issue.  But I’ll do a quick check on some of the basic stuff first (has new plugs, can’t imagine valve adjustments moved while static, i suppose i can check TPS and Throttle body sync, and do all that pretty quick).  Maybe I’m an idiot and didn’t check the air filter…. Sitting around for years maybe critters got up in there.  Hmm.  Love removing that tank….

[Tomchri]

Good.   Yes they need food. They have chrome piston rings, so a little dose of starting fluid just to se if she was interested. Wild quess, still filty injectors. Sounded like everything else was sorted  .  
Cheers Tom.

[Gmc28]

Hah, it’s alive and kickin…

let that seafoam do its thing for a couple more days, and the carb cleaner sprayed up into the air adjustment screw ports, and was getting ready to strip off the tank and air box, but cranked her up one more time to check TBS.  Behold, she coughed a couple times, then ran just fine.  Checked TPS, (slightly off, fixed), and TB synch, idle adjust, and a few other misc/normal things, and now she’s pretty much purring.  

Well, now I’ve probably jinxed it.  Still need to get her on the road to the gas station for a test flight. 

Assumption is that it was all just a mess of old gas.  Note that my crappy memory was mostly at fault, as it was about 4yrs that she sat there, when i checked my records, but in my head i was thinking 2yrs max.  It was clear premium, with a stabilizer added, but 4yrs is just too much.

a question which i assume is common, but I’ve never really thought about it, what do folks do with show bikes that usually sit and maybe get run once or twice per year?  Drain all fuel, then re-prime for the occasional start/run?  Or just be sure to replace all the fuel each year?

i know my old flat-slide Mikuni carb’d Suzuki doesn’t like any of those options.  Running it dry, or stabilizing the fuel each fall, but next spring she does not like to start and run properly on that first wake-up from hibernation. 

[gstallons]

You run straight gasoline and Sta-Bil for alcohol free gasoline.