Doing a Fuel injector replacement - what are these brass bits for?

[RangerRick]

So I have the 2 injectors, one is pictured; in the other picture is the kit for the installation, which includes new gaskets, screws, Banjo bolt with washers; but what are the 2 brass threaded items with the o rings for? It shows they screw into the unit on the left side that holds the injector in place. The service manual makes no reference to these and how to adjust. I see no reason to even mess with them.

[BLUEKNIGHT911]

So I have the 2 injectors, one is pictured; in the other picture is the kit for the installation, which includes new gaskets, screws, Banjo bolt with washers; but what are the 2 brass threaded items with the o rings for? It shows they screw into the unit on the left side that holds the injector in place. The service manual makes no reference to these and how to adjust. I see no reason to even mess with them.

... I'm sure they come set to the necessary specs ..... Mike

[RangerRick]

here is a picture of the left injector housing and the two brass units are screwed into it. I assume they will stay in when removed but have no clue what they do. The black arrows show the 3 small bolts that hold the injector housing in place

[hypurone]

Weird! Kinda looks like Air bleed screws for idle trim?

[RangerRick]

I'm wondering if this is what these screws do. Can't image why you would replace the screws when replacing the injectors

Throttle bodies are precisely synchronized at the
factory. Replacement throttle bodies do not require synchronization to a specific engine.
NOTE: Under normal conditions, the ECM has
the ability to compensate for throttle body variations between both cylinders using the fuel
injection system

NOTICE Do not attempt to adjust the synchronization screws on the throttle body. Any
tampering with the factory settings may result
in reduced engine efficiency.

[RangerRick]

Guess when you own this old of Spyder, there is no 998cc mechanics that can enlighten me as what exactly those screws do and WHY would they even need replaced?

[Peter Aawen]

Guess when you own this old of Spyder, there is no 998cc mechanics that can enlighten me as what exactly those screws do and WHY would they even need replaced?

I'd think that it's More likely that no-one still working on &/or riding a V-Twin Spyder has yet needed to replace just the injectors!

These Engines are pretty reliable & robust, and particularly in the Spyders, they tend to just keep on running strongly & reliably - or until one of the ancillary components fails, like a water pump, magneto, clutch, or occasionally, the trans itself! But the engines themselves & their injection systems generally seem to keep on keeping on, unless either long term neglect or an unwitting operator does something to kill them; and to do that, it's usually something pretty drastic! So while I've seen a few stuffed injection systems on Spyders, but in every case/whatever their 'stuffing', they've ended up taking out a bunch of other stuff too, making it a much more expensive repair and completely pointless to just replace the injectors, so I've never been asked to do that...

Basically, for most of them I've seen, by the time they get to need to replace injectors &/or do significant work on the engine that'd require injector removal/replacement, there's enough other expensive stuff needing fixing that it's easier/cheaper &/or a more viable option to get a complete replacement machine!

So I hafta ask, what've you done/come across that warrants just replacement injectors??

[RangerRick]

Well the bike had 6,000 miles when i bought it last year, and just off idle it would surge bad at times and now and then a dead miss or stumble. I did the canister removal and blocked off the vacuum line to the canister, but left the purge valve hooked up to the power connector, but no hoses hooked to it. It had a lot of oil in the stock air filter housing around the intakes. So I did an old school crank case vent system I ran it down and under the the spyder. I did spray carb/injector cleaner in the throttle bodies when running. Still did not make much difference in the problem. I put the good spark plug wires on sold by one of the sponsors and iridium plugs, still the same issue, I then yanked out the air filter system and put the open round filter on that others have done. Still same issue at times. I ran 3 or 4 cans of injector cleaner through the bike in the last year. There were also times i would start cold and it would die then restart and the rpm would fluctuate as much as 500 - 1000 rpm. but it always ran great at speed and full throttle. So I thought maybe one of the injectors was badly gummed up but then again it runs fine at speed, but occasionally it will stumble if cranking full throttle at slower rpm. I also have put on the pedal box and that made the throttle so much better. I'm thinking I may just need to remove the whole throttle body so I can give it a good cleaning with carb cleaner, not sure what else to do at this point.

[Bfromla]

Accidental **BONUS**Spare parts

[Peter Aawen]

Accidental **BONUS**Spare parts

Yeah, I gotta - I really doubt those extra bits have anything to do with your issue, unless maybe they've been in & out a few times for some reason & the 'O' rings are shot?? Then again......

...... I'm thinking I may just need to remove the whole throttle body so I can give it a good cleaning with carb cleaner, not sure what else to do at this point.

IIRC, there were some throttle body issues on earlier versions of these Spyders; and again, IIRC, I reckon there was a recall for the pre-2013 models and a software update for the 2013's sometime around mid 2013 or so that resolved these issues, particularly for all the newer of the V-Twin models....

So maybe you might want to do some searching thru the older threads here to see if there's anything in them to help/what they came up with back then; &/or possibly get some of the technical details or at least the applicable TSB details to see if anything in them can help? But it does look like you've covered most of the likely causes, so I'd say it's probably gonna be a bit of a lottery from here on in?

Mind you, just a bit of a thoughty here, and probably just me clutching at straws; but have you checked the injector pulse circuit &/or relay/s?? I recall tracing an odd & otherwise frustratingly 'resistant to any of the usual fixes' case of 'the occasional stumble when cranking full throttle at slower rpm' to an injector pulse relay that was breaking down under load once it got a little bit warm but not quite up to 'normal running temperature', altho all the repeated checks done on it before then had suggested it was fine.... . It was only by fluke when I happened to be in the process of looking for other things when I thought I'd check that relay yet again for Judtin's sake, and so I happened to catch it right when the stumbling occurred, revealing that the relay wasn't always working as it should; but once I saw that it WAS stuttering/stumbling & so interrupting the smooth timing of the injector pulses, a simple replacement of the relay resolved the problem!

Can't tell you much more, can't remember much more... But maybe replacing a relay or two, then possibly swapping them around might be worth a shot?

Just Sayin' Good Luck!

[RangerRick]

Thanks Peter, for the reply. Will definitely check out those injector relays.

[Bfromla]

Sent copy to Tech bud & said. “ on the forum question he doesn't need to mess with them”


” They look like air adjuster screws but the factory seals that off. “. Hopefully helps

[RangerRick]

so far not having much luck figuring out how to find the "injector pulse relay" on the microfiche. or on line. I see some relays listed but it does not say what they do.

[Snowbelt Spyder]

Rick, I think that your project is getting bogged down in the weeds. There's no injector pulse relay. I've never seen one on any of the 998 diagrams. On your 2013 ST, the injectors receive constant DC power from fuse F6 in the left fuse box. F6 feeds other items as well. That fuse gets power from the Main Relay R5 in the LFB. The other side of the power to the injectors goes directly to the ECM. The ECM pulses the injectors. There's no relay that could possibly pulse the injectors thousands of times a minute.

Those two other parts you've been noodling over don't look as though they adjust at all. That they just screw fully in and seat. They are listed as parts to the "Repair Kit". So, either replace the existing ones with the new or leave the existing ones installed.

[RangerRick]

Rick, I think that your project is getting bogged down in the weeds. There's no injector pulse relay. I've never seen one on any of the 998 diagrams. On your 2013 ST, the injectors receive constant DC power from fuse F6 in the left fuse box. F6 feeds other items as well. That fuse gets power from the Main Relay R5 in the LFB. The other side of the power to the injectors goes directly to the ECM. The ECM pulses the injectors. There's no relay that could possibly pulse the injectors thousands of times a minute.

Those two other parts you've been noodling over don't look as though they adjust at all. That they just screw fully in and seat. They are listed as parts to the "Repair Kit". So, either replace the existing ones with the new or leave the existing ones installed.

Thanks for the post, yes I think I will just learn to live with it acting up at times, as its only under 15-20 MPH

[Peter Aawen]

Sorry Rick (& Doug ) I should've been clearer in my use of terminology, and instead of using 'injector pulse relay' maybe should've used 'one of the relays that impacted the smooth delivery of injector pulses' - but I did say it was a fluke that I found the intermittently dodgy relay amongst the collection, and hoped that my earlier comment:

"...just a bit of a thoughty here, and probably just me clutching at straws..."

followed by my last point:

"Can't tell you much more, can't remember much more... But maybe replacing a relay or two, then possibly swapping them around might be worth a shot? "

would've suggested that I wasn't offering a potential definitive diagnosis, but rather suggesting you might look at all the relays & maybe explore that side of things further?!

BTW, have you had a look for any of the earlier info/discussion on Throttle Bodies?? I think I did offer a thought about that too.

[Snowbelt Spyder]

Thanks for the post, yes I think I will just learn to live with it acting up at times, as its only under 15-20 MPH

Don't know exactly what it's doing, but 99% of the issues with the 998 acting up are solved by:

- Replace the two vacuum lines on the MAP sensor
- Inspect the throttle body mounting boot for cracks and replace if required
- Perform Canisterectomy
- Replace plugs and wires
- Run Seafoam through it periodically

Good Luck with it.

[RangerRick]

Don't know exactly what it's doing, but 99% of the issues with the 998 acting up are solved by:

- Replace the two vacuum lines on the MAP sensor
- Inspect the throttle body mounting boot for cracks and replace if required
- Perform Canisterectomy
- Replace plugs and wires
- Run Seafoam through it periodically

Good Luck with it.

Thanks for the reply, I have done all the above mentioned items, and that did not seem to make a difference. I even sprayed starting fluid around the base of the throttle body and on all the vacuum ports were hoses attach and there was no increase in the Idle RPM

[IdahoMtnSpyder]

here is a picture of the left injector housing and the two brass units are screwed into it. I assume they will stay in when removed but have no clue what they do. The black arrows show the 3 small bolts that hold the injector housing in place

That is a pic of the fuel rail. The brass pieces have the shape of needle valves meant to adjust something. The manual says the idle is set at the factory and is not to be adjusted. Putting all that together I say they are the idle speed adjustment screws. Since you're not supposed to deal with them that is why they are not identified in the manual.

I would replace them and be prepared to have a fun game of getting the idle adjustment set correctly. My guess is they are crudded up and that is why you have a rough running engine.

[RangerRick]

guess I could count how many turns to seat them and then back out the new ones the same amount

[IdahoMtnSpyder]

guess I could count how many turns to seat them and then back out the new ones the same amount

That would be a good start. The big challenge will be to get them set so the idle is balanced between the two cylinders.

[TONYO]

Dude.....My 2014 st is surgein as well. Did ya ever figure out what was wrong?????? TYIA Tony