Hi all. I pulled the plug from the vertical cylinder and noticed there was black oily stuff all over the threads and around the tip. Quite a bit of it. No oil above the threads and inside the spark plug tube. What gives? Could the oil be unburnt fuel from running really rich? Plug only has 1K miles on it.
Any chance you can take a pic?
Quote from: ducpainter on February 03, 2013, 04:26:02 PM
Any chance you can take a pic?
I wish I thought of that, but I cleaned it up already. Black and oily is all I can describe it as-- from halfway up the threads all the way to the spark gap. After I wiped it off, the plug looked normal. The other plug looked fine.
Carby or injected?
It could be fuel, or oil. Hard to say.
If it continues, take a pic.
It's possible it could be a dirty/leaking injector, or it could be a bad valve guide seal, or a coil issue, or simply a bad plug.
You might switch the plugs to see if the problem swaps cylinders.
Quote from: ducpainter on February 04, 2013, 06:06:10 AM
If it continues, take a pic.
It's possible it could be a dirty/leaking injector, or it could be a bad valve guide seal, or a coil issue, or simply a bad plug.
You might switch the plugs to see if the problem swaps cylinders.
Thanks! In addition, I just measured my valve clearances and found that they're way out of wack. Intake closer clearances are much too large (both intake and exhaust) and openers are too small (exhaust). I'll fix that first and then keep an eye on the spark plug as you suggested.
Quote from: ducpainter on February 03, 2013, 04:26:02 PM
Any chance you can take a pic?
He's got the same issue I have ... I'm thinking It's a bad valve seal...
By looking at the pics I've posted u can tell that there's oil going in the combustion chamber somehow.. there's no black smoke coming out ,and the oil level is not going.down ... so I think there's a little oil coming in mixing with gas .. I'll try to replace the valve seals if I can since both my heads r out .. and see how it goes ...
Quote from: JoeP on February 03, 2013, 07:47:59 PM
I wish I thought of that, but I cleaned it up already. Black and oily is all I can describe it as-- from halfway up the threads all the way to the spark gap. After I wiped it off, the plug looked normal. The other plug looked fine.
Does it look similar to this?
(http://sphotos-b.xx.fbcdn.net/hphotos-ash4/295085_10152493317935113_1710424699_n.jpg)
Quote from: svp88 on February 04, 2013, 08:02:12 AM
Does it look similar to this?
Yes but much worse. The oily stuff was almost dripping off the plug.
Quote from: JoeP on February 04, 2013, 12:32:20 PM
Yes but much worse. The oily stuff was almost dripping off the plug.
Oh... Let me go home and check on those valve seals and o rings and I'll probably post a picture if i see Smth related to that ....
hey.. sorry for the delay !
so here are few pictures of my horizontal cylinder...
inlet Valve . (looks pretty clean)
(http://sphotos-a.xx.fbcdn.net/hphotos-ash4/379285_10152559527595113_1830996586_n.jpg)
(http://sphotos-a.xx.fbcdn.net/hphotos-ash3/561612_10152559530485113_1986964858_n.jpg)
exhaust valve. (looks dirty and oily)
(http://sphotos-a.xx.fbcdn.net/hphotos-ash3/557601_10152559527915113_1271156374_n.jpg)
(http://sphotos-b.xx.fbcdn.net/hphotos-ash4/405668_10152559531300113_110112911_n.jpg)
and this is how the valves look like
(http://sphotos-a.xx.fbcdn.net/hphotos-ash4/312404_10152485999585113_295494568_n.jpg)
the dirtiest spark plug is from the same cylinder.
(http://sphotos-b.xx.fbcdn.net/hphotos-ash4/295085_10152493317935113_1710424699_n.jpg)
so from my understanding it look like oil is passing through and its burning there...
inspected the valve seals and one of them (on the exhaust side) has a little cut on the top. the valve rods measured OK. so signs of wear there*
planning to replace all valve seals .
i say open up ur valve covers and inspect the seals carefully , see if there's any sign of wear or cuts/damage...
Thanks! I'll check the valve seals. Can they be replaced without pulling the valves out?
here are some pictures of my horizontal cylinders valve seals ... the green one is the exhaust valve seal , the black one is the inlet valve seal.
as you can see the exhaust valve seal is pretty beat up and worn .. (slid them to the valves and moved them up and down to test how much they were worn. so the green valve seal was moving up and down pretty easy compared to the black valve seal ) i will replace them all .. everything is open anyway .
(http://sphotos-b.xx.fbcdn.net/hphotos-prn1/65726_10152566032855113_702937655_n.jpg)
(http://sphotos-a.xx.fbcdn.net/hphotos-ash3/17494_10152566033920113_1776653750_n.jpg)
(http://sphotos-b.xx.fbcdn.net/hphotos-ash3/526944_10152566035485113_532041699_n.jpg)
(http://sphotos-b.xx.fbcdn.net/hphotos-prn1/46694_10152566036590113_1252342683_n.jpg)
(http://sphotos-b.xx.fbcdn.net/hphotos-ash3/600503_10152566037205113_68814340_n.jpg)
Quote from: JoeP on February 09, 2013, 07:45:23 AM
Thanks! I'll check the valve seals. Can they be replaced without pulling the valves out?
i dont think so ... the rocker arm is on the way .. i mean u can but u will have to force it out through the rocker arm ... (i wouldn't risk damaging the new valve seal )
(http://sphotos-a.xx.fbcdn.net/hphotos-ash4/379182_10152566034830113_1028778873_n.jpg)
So what exactly is the process for changing the seals? I was under the impression for some reason that the valves could stay put even though it'd be more difficult. That picture of the rocker explains I may have not fully understood the problem as I didn't have the bike open and was just reading forums.
They can, but the valves must be held in place so they don't drop down and caution must be used to not scratch the valve stem.
Quote from: thorn14 on February 10, 2013, 09:42:00 PM
So what exactly is the process for changing the seals? I was under the impression for some reason that the valves could stay put even though it'd be more difficult. That picture of the rocker explains I may have not fully understood the problem as I didn't have the bike open and was just reading forums.
It's pretty easy to remove the seals ... I have a tiny little Niddle nose plier (doctor style ) with that and a tiny little screwdriver to support the seal while pulling , it comes out easy .. same process for installation.. oil helps too ...
Okay cool. That's what I figured. Just ease it around the rocker. :)
Quote from: thorn14 on February 11, 2013, 08:03:11 AM
Okay cool. That's what I figured. Just ease it around the rocker. :)
if you are gona go for it let us know if that solved your problem
Quote from: thorn14 on February 11, 2013, 08:03:11 AM
Okay cool. That's what I figured. Just ease it around the rocker. :)
I've read that you can put the piston at TDC, remove the shim stack, then rotate the engine so the valve stem is below the closing rocker. This should give you enough clearance to replace the valve seal. Can anyone vouch for this?
Yeah, from what I understood it was similar to checking valve clearances, and the valve would drop and hit the piston/be held in place with forceps or otherwise. The rocker arm being in close proximity and requiring care in order to not damage the new seals is what I was concerned with from the earlier pictures.
I won't be making the seal swap for another week or two.
valve stem seals usually rely on a little coil spring inside or outside the seal to keep tension on the seal. You don't want to damage that spring or all your work will be for naught. It's not like you can safely stretch the seal onto the valve stem. If you cannot get the seal clean and easy on the valve stem then you will need to pull the rocker shaft and rocker. That is not a big deal in and of itself. One way to hold the valves closed is to use air pressure down the spark plug hole.