Persistant single cylinder problem

[Re-Vision]

jetav8r appears to have done considerable research.

Not familiar with which wire colors do what. Hopefully somebody else can chime in on that one.

http://www.jetav8r.com/Vision/IgnitionFAQ.html#a9p0

Click on 9. Checking TCI module (Power Checks)

Plus I have a bike with the tank off and a harness here at my desk.     BDC

[Rick G]

jetav8r, who's handle around here was leather, was a sharp fellow . He was also a Warthog pilot in the gulf war. I miss his fellowship around here!

[tig5]

Bike seems to be running well after swapping the coils over, so I'm suspecting a poor ground or a loose connection. Stoked to be riding again. I've noticed a tiny flickering of the oil lamp so I'm going to pull the pump and clean out any debris. It starts easily cold and idles well but the idling and starting ability diminishes a bit once it has warmed up. Could this suggest it's running a tad rich?

[QBS]

Sorry to have to say this, flickering oil light at idle is not good.  Suggest you go to 20w50 or even straight 50 oil at your earliest convenience.  Will crank with difficulty running straight 50 but might get you down the road for a while longer than otherwise.  Checking the pickup screen for debris is a good idea.  Maybe it's partially blocked, that would be good news.  Of course, the bad news is: Where did such debris come from?  All the best.

[iain]

Take the oil sender unit out of the bike ,,it screws in under the engine ...and stick the air gun in it and blow it out,, that fixed my flickering oil light problem,,it had a build up of sludge in it

Iain
NZ

[tig5]

Thanks guys, I'll try all those measures.

I just dumped the engine oil and there was quite a lot of light brown fluid appearing on top, not quite green but definitely lighter brown than chocolate. I'm wondering if I have coolant leaking into the oil?

This will be my first time removing the right engine cover. Do I remove the thermostat unit from the cover first or can I leave it attached? Do I need to drain coolant before removing the cover?

I see that people recommend replacing the water pump seal, is it #4 on this diagram? http://www.cmsnl.com/yamaha-xz550rk-1983_model8947/partslist/B-03.html
Do I need a genuine Yamaha part or is this something I can take into my local seal specialist and have them replace?

I'm new to this side of the engine. Any opinions appreciated.

Cheers

[tig5]

P.S Engine oil smells a bit gassy...

The bike has been blown over 3 or 4 times since last oil change. Petcock is a cheap replacement, no PRI function, I've a bad habit of leaving it in the ON position.

Bike doesn't blow any smoke that I've noticed.

[The Prophet of Doom]

Check your overflows are clear.  If they are blocked then petrol will end up in your cylinder, and sneak past the rings.  Makes starting a bugger as well.

[pinholenz]

Hiya Tig,

Great to meet up the other day. Thanks for the coffee. Did you get your WOF?

I have had a flicker on my oil light as well. I had the bike idling on its side stand  parked sideways on a slight downhill incline. Flicker went when the bike was up-right. However, it was also a bit low on oil. As I recall you didn't have a centre stand?

Oil change and a careful top up on level ground sorted my problem.

Is yours a gravity or vacuum activated petcock?

[tig5]

Hey John, likewise!

I failed my WOF on a handfull of things: Steering bearings need tightening, needed a rear reflector, need to reroute my throttle cable and zip-tie a few other cables out of the way. Also need to check for air leaks as my idle wasn't returning properly. This seems to be an intermittent problem and doesn't appear to be related to the cable or the throttle mech as far as I can tell. All up they it shouldn't take me more than a couple of hours to fix so I'm pretty happy.

I figured while the oil was dumped I may as well take off the right engine cover and clean out the pump filter screen. Do I need to remove the thermostat for this and do I need to drain the coolant? It looks like I've had a bit of fuel in my oil. I'm not sure if this was affecting the oil pressure, it did look a little thinner than it should have. I've removed the sender and I'll give it a clean but I thought I should get in and have a look under the right cover while I have the chance.

My bike has a side and a centrestand, I flick between them depending on which way the wind is blowing! Bike has been running like a champ until the oil light came on.

Oh by the way, I had another look at my house on google maps. Carjam.co.nz suggests the bike outside is not a phantom Vision but a humble Yamaha Scorpio. The chain gives it away a little.

Good to see you John! I hope you have a prosperous new year!

[QBS]

Its' been a while, but I seem to recall that the water pump has to come off.  Have been in there only once to replace a 72k mile clutch.  Also replaced the water pump twice.  All of this was a long time ago.  My trusty Haynes repair manual was excellent.  Every V'nary should have access to one.  Sometimes, working on a V can be counter intuitive or just strange.  A manual is a good thing.

[pinholenz]

Likewise, I can't recall what I had to do with the side cover I retrieved off a scrapper for POD. Done in great haste.
I do have a spare Haynes manual if you need one though.
I replaced my steering head bearings with roller bearings in order to put my bike back on the road. Pyramid Parts in Nelson have them in stock. It took me quite a while to get the lock nuts snug - they kept working loose. Some Loctite did the trick.
I have never come across a Yamaha Scorpio, but will look out for them now. You have piqued my interest. Deus Ex Machina in Indonesia do a pretty cool little cafe racer out of them.

[tig5]

I do have a Haynes manual thanks John. It just said to remove the thermostat unit and the side cover, I was just wondering what kind of liquid torrent I was about to run into but I figured that out.

Unfortunately 2 of the allen bolts that hold the thermostat to the engine cover were seized and stripped so I had to remove the coolant tubes from the cylinder heads and remove the cover with the thernostat still in place.

I tried the usual methods for remove the stripped allen bolts but they were well seized in there. Ezy-outs seem to have been well reviewed so I bought one and gave it a go. A quarter of a turn in and it snapped like a twig. So now I have 1 frozen bolt and 1 embedded ezy-out  >:(
I think I'll take it to one of the local machine shops and let them have a go...

I located the coolant weep hole and found it blocked up with a sandy clay-like substance. I think this may be insect related. When my bike was in bits I saw a wasp fly into the cylinder weep whole and the next day it was plugged in a similar way.

From the back side of the engine cover there are some prominent ridges that almost look like stress fractures in the metal. Are these normal? Part of the machining process? They look like oil streaks twoard the bottom of the photo but they are actually pretty substantial. I'll be interested to see what the other side looks like when I finally get the thermostat off.

[pinholenz]

Bummer.
It looks to me as if the cracks have got raised ridges on them which suggests that it is part of the casing cast and not really cracks at all. Best way to find out is to touch it with a grinder to take the ridge off and see what is underneath. Good luck!

[QBS]

I'm pretty sure some of those things are casting marks.  Also, hate to say it but some look like cracks. Pins idea should give more data.  Just have a really hard time imagining what kind of forces are in this area that generate such cracks.

[fret not]

If you can get the piece of the extractor out of the Allen head screw you can use a 1/4" or 7mm drill to drill the head off the screws and slide the cover off, then you can use a vise grip or other tool to remove the screws.  A couple hammer blows on the ends usually loosens them so they come out easily.

[Rikugun]

From the back side of the engine cover there are some prominent ridges that almost look like stress fractures in the metal. Are these normal? Part of the machining process?

I've seen this on other cases and covers before. As ugly as they look I would not concern myself with them. As stated they are from the casting process. If those marks were on the outside of a cover and oil was weeping from them, then I'd be concerned.  :)

To add to fret nut's broken screw suggestions, I'd also apply heat to the aluminum bosses where the screws are prior to your next removal attempt.

[tig5]

Thanks guys,

Heat and drilling the ends completely off are about the only 2 things I haven't tried. I'll give that a whirl and take it to a pro if I don't make any progress.

The ridges definitely are raised, it will be interesting to see what the back looks like. I also couldn't imagine how or what would cause cracking here.

[Rick G]

I have mentioned this many times before , but here goes again.  Easy outs are miss names . The should be called easy breaks.
They do not work 99 % of the time , instead they cause a worse problem, a piece of hard steel which can not be drilled .
My method of  effecting this type of repair is to carefully put a dimple in the centre of the  broken off screw and start with as small a drill bit as i can  and work my way up , until the  there is nothing left with the threads , which can be picked out with a tiny screw driver.  In the event that you drill the hole slightly off centre , merely install a helcoil . Every motorcyclist should  own a 6mm  Hilicoil kit.

[The Prophet of Doom]

Dead right about the impossibility of drilling out hardened steel, though you can slot it with a dremel cut-off wheel. 

If I have to drill out a screw I'll usually just tap and go up a bolt size - as long the larger bolt head & hole fits.  My bike was a rusty thing - it's got oversize bolts all over it now.