Steamer Misfire question (and new member introduction)

[Suitor_Stu]

the plug comes out of that #2 as a virgin with no soot and has a spark when checking & he swapped coils around too and made no difference .

this much is true.

Am off to the hospital to get my cast off today so will be doing a wee bit of work on it when I get back so I'll no doubt keep y'all posted

[Suitor_Stu]

Okay Okay, so got my cast off today and am now hobbling around without the aid of crutches, which is good news!  However I still haven't got the full range of flexion/extention in my foot back yet enough to shift gears on my bike (well I could on my Enfield as its a Right Hand shift, but that would need an MOT first).  I am taking this as a positive though - no excuse not to sort the Tig in the coming weeks now!

So anyways, got out with my compression tester today and on an admittedly cold engine recorded pressures of Cy1 - 150psi, Cy2 - 160psi and Cy3 - 160psi.  Now I know this is cold, but the problem is there from cold so I can use these as a gauge and as such there is nowt wrong with Cy2's compression - so back to fuel again.

Now that I have the rocker cover off though I thought now is as good a time as any to pull the intake cam and do some re-shiming.  So after much cursing and swearing I fashioned a makeshit shim puller out of the magnet of a tankbag and boy did that help!  Typically though when I pulled the shims for Cy1 and Cy2 intakes, only one of them had a number stamped on it, so off to the hardware store to buy a micrometer I went...upshot being I have 3 shims at 2.7 and 1 at 2.6.  Will prob not bother to touch the shims in Cy1 (can't see any point changing what is an acceptable limit to one too high one just for the sake of a few more miles before I need to do one again), but from Mustang's link above it's 25mm ones I'm looking for?  Bike shop should have them right?  What about the gaskets for crank-case and cam chain tensioner, I've got a tube of 'Instant Gasket' or do I have to use the preformed ones (my worry is their availability - ie can't find any)?  

Anyway, that's tomorrow's job...Then it's on with the casings and back to the carbs...

Cheers again guys, I think I'd have sold the giT, sorry Tig by now if it wasn't for here.

[JetdocX]

Unless your valve cover gasket is hosed, reuse it.  Sealant around the corners and where the bores are for the cam bearings (edge of head left and right).

Cam chain tensioner takes a soft washer for a gasket.  Re-use it as long as it's in good shape as well.

Edit:  Sorry, there is a gasket on the tensioner body.  Same as above.  If it looks good, reuse it.

[Suitor_Stu]

aye, the valve cover one looks fine, as does the tensioner one so I can just reuse them then.  

I mullered the crank-case one getting it off though (as in had to scrape parts off it was that bad!), so would the insant gasket stuff suffice for that?

[Mustang]

should work fine .............the original is just a paper gasket anyway .

[Sin_Tiger]

There are umpteen makes of "Instant Gasket" in the UK, some are better than others. I would get ahold of some "Blue Hylomar" and use that where needed, it's recommended for anywhere that might get in contact with engine oil. Most decent motor factors will stock it.

I have even used it on its own in place of an original paper gasket a few times.

[JetdocX]

+1 on the Blue Hylomar.  Developed by Rolls-Royce for use in their early model turbojet engines!

[MtheTiger]

+1 on the blue Hylomar here also.
Even fixed a tiny tank leak with it (sweating gas from the RHS middle fairing bush) and sealing my new petcock in place.

[Suitor_Stu]

Right, hopefully nearly out of the woods...just got the valves sorted - bought a couple of new shims and swapped a few around so now all my intakes are 0.13-0.15mm.  Cushty.

Pieced the whole thing back up again, and i dunno if I'm just convincing myself here, but it sounded a bit smoother when started was thumbed...still something there mind you but I can't have done it any harm.  Again, cushty.

Did the increased idle thing and it didn't really make a difference to the misfire, still one there but when I pulled the plugs again it appears that may have caused the misfire to jump from cy2-cy3, although I'm not 100% on this as I don't think I put all the plugs back in exactly the same slots (will get some a fresh one tomorrow and give it a go again), but it looked as if there could be blackening of plug 2 this time...Hooked up my newly bought 'carbtune' though and they were all out of sync with each other so I'll be syncing tomorrow (I work fairly late and have a few young families around me so don't like to fire the bike up after 9ish out of courtesy which is why it takes me so long!).

I'm afraid that I like to try and understand problems before I try and sort it, so am just trying to work out whether there is a possibility that adjusting the idle screw brought carb2 into the correct firing range but that it also pushed carb3 out of it?  Does that sound about right?

[Mustang]

if turning the idle adjuster up made #2 fire then #3 should have gone way up and made the engine race as the adjuster is connected to the linkage that runs all three carbs

I am not ruling out coils at this point in time either ..........but first get the carbs synced to one another

check the header pipes when it's running if they are all hot then you are firing on all 3 if you got a cold one thats the dead cylinder

[Suitor_Stu]

if turning the idle adjuster up made #2 fire then #3 should have gone way up and made the engine race as the adjuster is connected to the linkage that runs all three carbs

In retrospect I may have jumped the gun slightly there - the most realistic thing that happened is that a plug from a firing cylinder ended up in cy2 and I forgot to give it the wire brush treatment beforehand...I think I just got overexcited at a possible end to the situation!

still not convinced it's coming out wet (googled 'wet spark plug' and it looks nothing like them) but is there doesn't look like any way it could not be getting fuel to just the middle carb.  In my manual the mikuni in the pic has 2 fuel lines feeding into the bar on the carb but mine only has the one between carbs 2 and 3 so I wouldn't have thought there would be anything else that would be causing a blockage.

[Suitor_Stu]

oh yeah and cheers for your patience!

I'm only an enthusiastic amateur with the tinkering but I am willing to listen and learn.

[Mustang]

when you have the petcock turned on and motor off ....open up the drain screw on the bottom of carb #2 and see if gas comes out .

have you had the mikunis out of the bike and opened em up to see if they are gunked up and or worn parts inside ?

you could have a stuck float assembly that is not letting the needle valve open to let fuel in to the float bowl ..........

[JetdocX]

I don't see the need to turn the fuel petcock on until you know that no fuel is getting to #2.  Then try on, if still none, try reserve.  You could learn a lot from that little exercise.

[Suitor_Stu]

Nup.

Carbs sync'd, fuel delivery on all 3 carbs, compression still okay and still misfire.  Now it appears more intermittent though, as in sounds like it could be almost idling fine with just the odd crap-out, then the engine melts down on a quickly opened throttle.  A touch (or hover - I'm not a total idiot!) test of the downpipes confirm that they're all hot...

So coils again then?

Suppose if that's the case I gotta expect (and therefore replace) all 3?

Honestly at this stage if I had just a wee bit more money (or would accept my R100RS as a trade-in) I'd be taking a wee trip to the dealers down the road replacing the bugger right now with that nice R1150GS they have in showroom...the weather is getting too nice to be spending it tinkering!