3rd exhaust pipe a bit cooler than the others

[Slaninar]

What could be the cause of this? Carb were balanced some 3k kms before, this winter, by a mechanic. Perhaps not good enough? Spark plugs and cables seem OK - all the pistons seem to be running.   

[unfazed]

It probably dresses better

[darrsi]

It probably dresses better

 

[His Dudeness]

Could be a lot of things. Try the handy stuff first. Take the plugs out inspect and clean them. See if that helps if it doesn't try trimming a little ht lead off. If that doesn't help try taking the plug caps off and swap them and see if the problem moves with the cap. If it doesn't then you'll have to go a bit deeper and do some proper testing

[otis]

First easy thing I would do is swap 2 plugs around and see if the problem moves with plug, then you are not messing with HT leads and caps. If no change then try caps.

[Slaninar]

Seems to make same sounds and running with 3rd plug wire taken off. Must be running on 3 cylinders only.

I have tried switching the plugs - 3 & 4. Same.

So it is cables, or something else?


It was working fine. Took it apart this winter to change cam chain, check valves. Mate put it back together, since I had to go run to work my regular job in the middle of the "operation". He's a mechanic. It has been running strange ever since. Thought it was just me. Seems I have been running on 3 cylinders for the last 1000 kilometres.

[teedeeii]

Hi. Have you solved the problem? I have same problem, with 2nd cylinder. It wakes up with 3200rpm. It also runs when engine is hot for example after motorway driving. Then after few minutes with slow driving, it starts running without 2nd cylinder. There is spark in the plug. I have changed plugs, wires, coils with each others...and cleaned 1 and 2 carburators jets? What next? I haven't sync carbs. Should I?


JM -Finland


FZS 600 Fazer '02

[unfazed]

If it was coils the it would effect 2 and 3.
Swap the plug in cylinder 3 with the plug in cylinder 4? It might be a plug breaking down.
If plugs are ok, then it is carburettor, incorrect valve clearances or piston ring issuses associated with cylinder 3. Would not be the first time someone mixed the shims up when doing the clearances.
A compression check will rule out carburettor being a problem.
Teedeelii;
Check the valve clearances and then synch the carbs. Might be no harm to do a compression check also.
 

[Slaninar]

If it was coils the it would effect 2 and 3.
Swap the plug in cylinder 3 with the plug in cylinder 4? It might be a plug breaking down.
If plugs are ok, then it is carburettor, incorrect valve clearances or piston ring issuses associated with cylinder 3. Would not be the first time someone mixed the shims up when doing the clearances.
A compression check will rule out carburettor being a problem.
Teedeelii;
Check the valve clearances and then synch the carbs. Might be no harm to do a compression check also.

Have swapped plugs 3 & 4 - same, 3 doesn't work even with the plug that was working in 4. 4 was working with the plug from 3. So plugs must be OK?

2nd cylinder works, so coils must be OK?

Coud it be the cam chain not fittet properly (timing)?
Or the carbs?


Valve clearances were OK, nothing was touched.

[Slaninar]

Spark is OK, so it's not the cables.

Spark plugs are probably OK.

My next guess is the carbs - stuck or something, no fuel in the cylinder?

[Paul]

I've had this problem.


Went through the usual procedure of swapping plugs etc.


Finally [size=78%]I ended up cleaning the carbs and the problem went away. [/size]
[/size]
[/size]

[unfazed]

If it was coils the it would effect 2 and 3.
Swap the plug in cylinder 3 with the plug in cylinder 4? It might be a plug breaking down.
If plugs are ok, then it is carburettor, incorrect valve clearances or piston ring issuses associated with cylinder 3. Would not be the first time someone mixed the shims up when doing the clearances.
A compression check will rule out carburettor being a problem.
Teedeelii;
Check the valve clearances and then synch the carbs. Might be no harm to do a compression check also.

Have swapped plugs 3 & 4 - same, 3 doesn't work even with the plug that was working in 4. 4 was working with the plug from 3. So plugs must be OK?

2nd cylinder works, so coils must be OK?

Coud it be the cam chain not fittet properly (timing)?
Or the carbs?


Valve clearances were OK, nothing was touched.

Back to the carbs then.
Use a piece of clear plastic pipe on the float bowl drain outlet to check the float level before you remove the carbs.
With the pipe on the outlet open the drain screw allow some fuel to drain out the pipe hold the pipe up next to the float bowl, Tape it in place or get some one to hold it. Now start the engine. The fuel in the pipe should settle around the top of the float bowl. with the engine running lower the pipe allowing some fuel to drain out and put it back next to the bowl again. Fuel should settle quickley to the correct level again.
If the above is ok it rules out a sticking float or blocked float valve.
When checking the jets and orifices always blow then out in the reverse direction of the normal flow. Any loose dirt is blown out the way it came in and not blown further in to become pernamently stuck.
 

[Kentish]

I would run some fuel cleaner through it first. It works you know  . Try to get a nice strong mix so yo don't want much petrol in there. Maybe a few litres then put a load of the fuel cleaner in and go for a ride.....Might save you taking the carbs out...

[teedeeii]

My problem is now over. I found the fault from carburetor. I took off the cap and vacuum valve. Then I saw there was alittle of fuel around throttle plate -only in second carburator. It cylinder so ran with rich fuel.


I took out whole carb-combination. The pivot needle of float was ok...but the "hose-housing" of a pivot needle had an o-ring on outside of it.. It was ok, when I looked it. But it has became too thin, and the fuel flow up next to the o-ring. So 2nd cylinder got too much fuel. Now I have a new o-rings and Fazer is like new bike!

[His Dudeness]

Well done teedeeii. I like your style Post 1 I have a problem. Post 2 I've fixed the problem. No messing about there!

[Slaninar]

New spark plugs will arrive tommorrow.

Took it for a ride yesterday. When it's hot, all the 4 exhaust pipes seem to be the same temp (too hot to - drying cotton cloth very quickly). But when I start it from cold, the 3rd pipe heats up a lot slower.

When on open road, at some 120+ km/h, the wind seems to slow the bike down. Causes the effect similar to opening and closing the throttle. Didn't notice that before.

To my ears, the engine sounds very good, like it's running fine.

Maybe it's just me.   

[Slaninar]

Took the bike to the mechanic today. He said that it's normal for carbs to get dirty and stuck during the winter months of not riding. However, the last 3 winters were no problems with carbs. I rode the bike a bit more spirited and put some choke as well - to flush anything dirty from the carbs.

When I got to him, bike was working fine. Came home, let it cool down completely. Started it - the 3rd cylinder exhaust pipe was a bit cooler again!
But it seems to run OK now. There is a slight metal sound on the right side of the engine (like chain ticking slightly). But not loud at all. Is that normal and I just didn't pay attention? Valves were checked recently and were OK and the cam chain was changed recently also.

[Slaninar]

Not much time for riding so far this year.   

Rode the bike today, gave it some gass - it works and sounds sweet now. Don't know what the problem was, but it seems to have gotten out with the old fuel.

[Slaninar]

Back again.

Changed spark plugs for new NGK CR8E. Started the bike from cold, and put wet cloths just to test it. 3rd exhaust pipe takes about 2 minutes longer to dry the cloth compared to all the other pipes. The bike sounds good, runs good. Is this perhaps normal, for not all the cylinders to be the same?  After spirited riding I can not tell the difference, just when starting from cold, first 10-20 minutes.

The man who cleaned and synchronized carbs said not to sweat it, not any 2 cylinders are ever the same, the bike sounds good, runs fine - leave it be.

I'm considering not touching anything and just riding as long as it sounds and runs fine.



One more thing, perhaps a stupid question - anyone experienced bike slowing down when headwind starts - at speeds over 120 km/h (80 mph)? No drop in revs, just the whole bike seems to decelerate a bit, then mooves normaly on. Without altering the throttle. It doesn't happen when going slower, no matter which gear or revs. Like the feeling when a big lorry passes by, but just caused by wind. Didn't notice it last year. Perhaps it's just me - or the wind. 


....scratches head.

[Buzz]

Slaninar, my bike's exactly the same, perfect performance when hot but 3rd cylinder takes much longer to heat up.  Takes a bit of choke and a few twists to get going, even in the heat of yesterday but after 2 mins at 3k it idles fine....still hunts a bit though.


Spark is fine, new caps, leads trimmed, K&N filter so I think it's a carb problem, probably a blocked pilot jet on No. 3...just haven't had the time to take 'em off and clean.