Misfire/intake popping.

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About 14 months ago while working in the city I took AnaSTasia off the road as she wasn't quite running as smooth as she used to.

I decided to do fork seals,shims, radiator hoses, some leaks plus tyres and do all fluids.

Anyway around November last I experience a tragic family event that gutted me so everything went on hold, so a few months ago I put her on a trailer and brought her home as therapy.

Its been a long slow road.

After sorting out some battery issues I finally fired up AnaSTasia. It took a while for her to start but when I did I could tell all was not smooth and there was heaps off black smooth as I revved her, probably flooded her. I also noticed more tappety than before I did the shims.

When Idling and when revved slightly I could tell it was not quite smooth, like timing not right, so too hard leave for another day.

So the next day when and fired up 1 st time tappet noise almost gone but still not smooth.

I checked the spark plugs ( Iridium that I have had for about 20,000kms) they were all quite black

Since then I have started her a few times seems as if getting a little better. New fuel--carby cleaner.

Any way a couple of days ago I got to operating temp and noticed running better when warm, so did carby sync some minor adjustment not really a lot, less than I would have thought.

The following day I fired her up again, Wont fire without choke when cold and it not that cold really, anyway got temp up not as warm as the day before and checked carbs and discovered quite a bit of discrepancy. Thinks out loud, I look at that later.

A few days ago I started her with a little choke and notice a little backfire though carbs, even with choke off still a little backfire. Increase revs a little and can here a little popping, all with air cleaner cover off.

I also smell what I call a pepper type smell from around the intake area, I related this smell to a sort of coolant smell , takes me back to an old car I had with coolant leak car heater system.

Yesterday I decided to obtain some standard plugs and on removing Iridium plugs noticed they are still black and quite damp.

After installing new plugs when starting I observed popping through intake but also noticed when revving slightly popping from all intakes plus felt as though more sluggish than before but slightly smother ,does that make any sense???

So before I start ripping everything apart unnecessarily can I ask a few opinions factual would be a nice, I feel may be necessary to pull carbies out etc.

I know plugs should probably be greyish and not damp.

Almost just now.
Choke cable and operation, checked and OK.
Ran for short all pipes hot.
Pulled No 3 plug quite wet at base of thread.
Pulled No 2 & 4 both black on bottom electrode ,No 4 more so, all plugs are new,minutes old.
Side note prior to taking off the road the engine didn't feel as sweet and smooth as she did say 5000km before, hence the reason for doing shims.
She has sat and not been started for approx 14 month hence carby concern.
Shim settings double checked and ok.
On just starting convinced I have a coolant leak that I can smell but can't see, ----more exploration

Cheers
Kappy
 
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Kappy,

Other listers have had success with "Seafoam". Add a dose to fuel, run it for 15 minutes and then let is set for a few days.

Jim
 

DAS

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good to hear things are going better for you and you're back to riding your ST. My ST 1100 also misses, pops and bucks when it is cold unless I give it full choke. It still takes a while to warm up but then it runs great.several years ago when I first got it I checked the spark plugs several times after a cold start and they were like yours, wet or black and sooty. Now I just ignore its being belligerent and get it out on the highway as quick as I can and it runs just great. I hope this helps. Keep us posted on what you find on yours.
 

Mark

Gotta make tracks
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In the other thread where you brought up this issue there was a mention of Seafoam.
I don't know if you can get Seafoam 'Down-under' so I though you might like to know how to make your own.
I found this site when I was doing a bit of research:
http://hildstrom.com/projects/seafoam/

Good luck,
Mark
 
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kappy5003
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Tks Mark,

No we can't get Seafoam in Aussie, cant even import it for some reason.

Will that really clean out a dirty system, I have sprayed a whole can of carby cleaner through the intake,its sounding a little better, but still have popping at the intake and you can hear the the miss at the exhaust.

Id rather not pull the carbies off, willing to try anything once.
 
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Looks like it's time to pull the carbs. The bike sitting for a long period then giving you the symptoms you mentioned would point to dirty/cogged jets, maybe a stuck float... or possible compromised diaphragm. Add to this the mention of the coolant leak that you cannot see, probably in the vee below the carbs... pulling them would help clear up both problems. You did not mention the age of the bike or total number of miles.
Replacing the carb isolators may be in order also due to hardening and possible cracking which could cause vacuum leaks.
After pulling the carbs, it's easy to remove the vacuum piston covers to check the diaphragms. After checking those, turn the entire assembly over and pull the float bowls, remove only the idle and high speed jets and clean them with a good chemical cleaner and a suitable non abrasive wire like tool. Re-assemble and run some fuel system cleaner through the next couple of tanks... then resync the carbs again after the through cleaning.
 
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kappy5003
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Hi Vinny yes leaning towards pulling carbs. I did forget to mention I have a 2000 ex Police ST1100 with current kilometres 97500 km(69,000miles)

Main issue has sat for a long time.

I discovered I can get 16 oz can of sea-foam from East Coast, is this stuff as good as people claim. Its $25.00 plus post here..and would cost about the same to make my own eg Kerosine is $7.50 per litre here.

Does this stuff alleviate the need to pull Carbs

Anyway I bit the bullet and removed the carbs, quite easy really better than I thought.

Once I pulled the carby out I think I found found my coolant leak seems there's a housing attached to top of block that's connected to metal pipe.

Also observed hose to thermostat is a bit iffy.

Pulled one float cover off a bit of dirt in there also quite a bit of dirt in the fuel from the float chambers, doesn't seem to bad but how much dirt does it take to mess with carbs.

Looking into intake of cylinder No 1 I observed a little more carbon on the valves.
 

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Does this stuff alleviate the need to pull Carbs
Depends on how dirty the carbs are... but since you have already removed them, not to worry about that.

Once I pulled the carby out I think I found found my coolant leak seems there's a housing attached to top of block that's connected to metal pipe.
It's time to replace the "O" ring under the metal necks, that one and the two others. Check the necks for pitting/etching from the coolant, replace as necessary. If I can remember correctly, they're not very expensive.

Keep us posted on your progress!
 

gmast1100

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Definitely need to replace those o-rings and be careful not to crack the elbows. Also would get some small rags in those intakes so nothing's drops down into the motor. Been down the route of pulling carbs twice. Once on my 91 that now lives in the grave yard and just recently on my 03 1100P.
 
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Replace the elbows! They are known to be prone to cracking once disturbed and you don't want to go back in there again.
 
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kappy5003
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Progress update.

Bike stripped pretty bare, bit scary Pic 1.

Well I've stripped the carby and all of it has been thoroughly cleaned quite dirty in parts Pic 4.

The pilot jets from No 2 & No 4 were a little blocked..

With everything off I observed the butterflies on No 1 & No 4 are slightly open :think1 is this a sync thing, however the butterfly is open at what would zero throttle ,should that be closed tight or not.

What do I mean by slightly open, when I shine torch at bottom of throttle body no light seen other end of No 2 & No 3, light is seen with same test on No 1 & No 4.

On inspection the to neck for the thermostat hoses and in good condition so I wont disturb them

The water cover in the centre of the block Pic 2, however has a leak, have ordered a new O ring, however this has a metal pipe that attaches to the hose that connects the bottom of the radiator, the metal pipe is secured by a bolt that secures it to the block between the rear of the timing belt housing and the engine block Pic 3, has any one any tricks short of removing timing belt.

In short the Carbs were in pretty Good condition just full of junk
 

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On inspection the to neck for the thermostat hoses and in good condition so I wont disturb them
This is a great opportunity to replace the "O" rings at a minimum... It's a lot of work to get back down there if they fail in the near future... it's a known failure with the 1100's.
the metal pipe is secured by a bolt to the block between the rear of the timing belt housing and the engine block, has any one any tricks short of removing timing belt
I would just make sure the clamp is tight and let it go if the hose feels/looks to be in good shape.
:) Not to scary if you take it a step at a time. Good luck!
 
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Well, for some reason, half of my post was lost.... here goes again.


The pilot jets from No 2 & No 4 were a little blocked..

With everything off I observed the butterflies on No 1 & No 4 are slightly open :think1 is this a sync thing, however the butterfly is open at what would zero throttle ,should that be closed tight or not.

What do I mean by slightly open, when I shine torch at bottom of throttle body no light seen other end of No 2 & No 3, light is seen with same test on No 1 & No 4
Once the jets are cleaned, the sync will change so the position of the butterflies will change when you dial them in. Having the carbs apart and cleaning the jets good will speed up the process a bunch. I would still use some fuel cleaners for a few tanks to get any residual dirt/film out of the carb passages. I had similar issues with my '99 and it took several tanks with cleaner to get it 100%.
 
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kappy5003
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This is a great opportunity to replace the "O" rings at a minimum... It's a lot of work to get back down there if they fail in the near future... it's a known failure with the 1100's.

I would just make sure the clamp is tight and let it go if the hose feels/looks to be in good shape.
:) Not to scary if you take it a step at a time. Good luck!
Tks Vinny,
Think there maybe a slight misunderstanding with regard the central neck that has metal pipe, the O ring has failed and I don't know if there enough room to replace the O ring with the Neck/pipe in place, as the metal pipe is secured by a bolt that secures it to the block between the rear of the timing belt housing and the engine block. So not sure whether there is any easy way to removing the pipe without having to remove timing belt etc.
 
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RE that water pipe - Just remove the two bolts holding the housing. It will then move enough to wiggle it off the pipe. No need to touch the pipe itself. Replace the o-ring and put it back together.
 
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Been a while since I've been down to that level with mine... about 3 years, and hard to remember the exact layout of the water pipes... Sounds like Bush has a fresher memory than I. Keep us posted.
 
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kappy5003
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RE that water pipe - Just remove the two bolts holding the housing. It will then move enough to wiggle it off the pipe. No need to touch the pipe itself. Replace the o-ring and put it back together.
Thanks Bush

I was a little timid at disturbing it, but went out this morning gave the housing a little wiggle and off it cam, will have to wait till tomorrow to order new o rings, public holiday here today.

My confidence has increased,I was a little timid at dismantling the Carbs, turns out not as complicated as I first thought. I've done most things on AnaSTasia my self, this is new ground for me will just have to wait till its all back together to see if the carby's fine.

Next I may have to try boring her out 1600 lol.
 
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ST1100Y

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...went out this morning gave the housing a little wiggle and off it cam, will have to wait till tomorrow to order new o rings...
Clean the surfaces and grooves with some abrasive fleece/wool (like plumbers use to clean copper pipes prior brazing; alternatively the green side of a Scotchbrite kitchen-sponge can serve) and maybe some kitchen/bath descaler (rinse off thoroughly afterwards).
I apply a slight smear of silicone-grease on all O-rings before installation; helps setting them in place, protects/nurtures the rubber and avoids twisting/kinking them during assembly.
Same (cleaning and small amount of silicone grease) on all the stubs and cooling hoses; also on the outside, aids proper seating of the hose-clamps.

While already in there also check/replace the small "internal bypass" hose, leading from that steel pipe up to the t/stat housing.

New radiator cap, new coolant thermo, new fan-stat (Klixon) and new radiator drain-plug + gasket could as well be focussed on.
 
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