still probs [Progress,but need help

[zman]

smoked on over run.After replacing valve seals no smoke but no1 not firing.
found it to be inlet valve not seated properly.lapped it in,put new head gasket on.

Now all fire but smokes all the time like a steam engine.

SO THESE ARE THE THINGS I KNOW
not sure if its related to what ive done or new problem

Cant get the carbs very well balanced.vacuum between 26 & 32. Then run out of adjustment.

carbs have fuel screw not air.spark is bright orange.And turning screw in or out makes little or no difference.

i have taken one plug at a time off so bike only running on 3 cylinders and it still smokes.i was hoping if it was one cylinder when i removed that plug it would stop smoking showing me which one is at fault.But seems to be all of them.

Apart from the smoke engine sounds great and reves well.

What do think

[Pigford]

If its got recent rings (new/rebore) run it on cheapo oil for a good hundred miles - give it a bit of stick and see if it settles down

[zman]

Just done compression test.And its gone low particularly on 3.
im sure valves are good but spoke to an engine shop and they are going to do a leak test on the head and check barrels.
They said if ive sorted head out this can show up a week spot in the bootom end.ie rings

[Al]

smoked on over run.After replacing valve seals no smoke but no1 not firing.
found it to be inlet valve not seated properly.lapped it in,put new head gasket on.

Now all fire but smokes all the time like a steam engine.
Have you filled the,. or coated the,.. inside of the exhaust with oil as a result of the comings and goings.
As Piggy said has it had rings recently or had the rings put on upside down?

SO THESE ARE THE THINGS I KNOW
not sure if its related to what ive done or new problem Question

Cant get the carbs very well balanced.vacuum between 26 & 32. Then run out of adjustment.
[i]They were in the low 20's previously (seperate post you made)so what has changed?
The only thing i can think of that changes the vacuum levels that dramatically is a change in cam timing. Has it slipped?
Is 26-32 the range measured for four carbs at the same time?
If it is then there is something dramatically wrong there. There should be no more than 2 millibars between any cylinder.[/i]


carbs have fuel screw not air.spark is bright orange.And turning screw in or out makes little or no difference.
Light blue, bunsen blue and yellow are all indicators of correct or near correct mixture strength. Red / Dark orange (i believe is an indication of burning oil)
Burning oil would account for a non firing cylinder and also possibly a dramatic change in the measured compression ratio depending on how much oil, its origins (bypassing the rings) and when it is present or absent.
Is the oil level too high and do you take the compression readings in the same order each time? If not then the process of testing each cylinder makes more or less oil available at the rings for subsequent cylinders!!
If youre not running on the road whilst this is going on i could suggest taking the oil level to the bottom line in the window.
Does it have a large oil cooler on it that is draining back down?
You mentioned prevoiusly that there was a lot of oil in the vacuum tube. Does this mean the vacuum tube belonging to the vacuum gauges?


i have taken one plug at a time off so bike only running on 3 cylinders and it still smokes.i was hoping if it was one cylinder when i removed that plug it would stop smoking showing me which one is at fault.But seems to be all of them.
If its sucking oil past the rings then that may make things worse as its pumping that oil unburnt (and a little petrol) into the exhaust

Apart from the smoke engine sounds great and reves well.
Thats a start at least

AL

[zman]

Thanks for your replies.
Engine apart again today
Put spiret in all boars.After about 3/4 hr 1,2,4 had dropped very slightly.No 3 about 3x as much as others.No3 was also lowest compression.

If compression is way down.70 and lower.I know this could be drawing oil up so smokes.Could it also be the reason i cant get mixture & vacuum balanced

[Al]

Wouldn't be at all surprised.
Wouldnt be surprised if that amount of oil in the cylinders didnt interfere with the correct operation of the compression pressure gauge either.

Are the crowns of the pistons wet looking?
Any more so than others? Number 3 perhaps!!
Any wetness in the exhaust ports or inlet ports?
Any signs of vertical grooves in the bores?
Any signs of discolouration on the walls of the bores?
Any pitting on the bores?
Any loose flakey material on the crowns of the pistons or the combustion chamber of the cylinder head? The type of thing that when dislodged could find its way between piston and bore or lodge between a valve head and its seat?
Got any pictures of whats going on.

AL

[zman]

Interesting comment about loose flaky material.
when i didnt have No1 firing there was no smoke
No1 not firing was inlet valve not seating correctly.
After i had good compression on all 4 and a bit of smoke.This got worse and worse which i thought was carbs/mixture.
then discovered compression had dropped dont know how.

[zman]

By the way there is flaky material about
Going to have barrels off and check things out

[zman]

Had Help from a local engine company.They said suden lose of the compression was due to a induction problem.ie carbs.not anything to do with engine.

Had carbs off & cleaned them.Back on bike & now balanced at 24.
The bike is still smoking.I believe to it being so rich.You can see unburnt fuel on the top of the pistons.Its like its flooding.
Float levels are correct

GOT ANY IDEAS

She still ticks over fine & reves well

[ZedHead]

Had Help from a local engine company.They said suden lose of the compression was due to a induction problem.ie carbs.not anything to do with engine.

How does that work? Unless the carb intakes/filter are completely blocked the engine should be still be sucking air through. I'm confused

[zman]

Im a bit to.How it could lose air on 1.2,4 & all on 3.I understand no air no compression.
I could see 3 had vacuum off the scale before i stripped carbs.


Engine company said if you have compression then it suddenly goes it to do with intake.
They said they have seen this happen with even new built engines.

[ZedHead]

I could be wrong but it sounds like a red herring to me