ideas on what happened?

kfsrq · Post by **kfsrq** » Mon Dec 10, 2012 9:05 pm

I think green is commonly used as a ground wire. I cannot say whether
ALL green wires are ground, but if I had to guess, that would be my guess.

IF that guess is right, then the way to toast a green wire is to make a short circuit between a wire that carries power and that green wire. I realize that does not narrow the problem down to any great extent, but I hope it helps at least a tad.

EDIT: (oops, I posted this before seeing all the posts in the thread.
so you have fixed the wiring and have some new fun [?] to keep you busy.)

LOUD MOUSE · Post by **LOUD MOUSE** » Tue Dec 11, 2012 6:56 am

Have you looked at a wiring diagram lately?. ........lm

kfsrq wrote:I think green is commonly used as a ground wire. I cannot say whether
ALL green wires are ground, but if I had to guess, that would be my guess.

IF that guess is right, then the way to toast a green wire is to make a short circuit between a wire that carries power and that green wire. I realize that does not narrow the problem down to any great extent, but I hope it helps at least a tad.

EDIT: (oops, I posted this before seeing all the posts in the thread.
so you have fixed the wiring and have some new fun [?] to keep you busy.)

davomoto · Post by **davomoto** » Tue Dec 11, 2012 7:54 am

Guessing and wiring don't go well together! There are two green wires in the headlamp bucket. The green with white band is ground, while the other green wire is hot!

Davo

Snakeoil · Post by **Snakeoil** » Tue Dec 11, 2012 11:23 am

I'll wade in at the 11th hour. I agree with Davo that guessing and wiring do not mix. The only way to troubleshoot electrical issues is with the wiring diagram, a DMM and a consistent methodical test, confirm, eliminate process. Anything else is dependent on luck. Wiring diagrams are easy, but overwhelm many. You only need to look at one circuit at a time and when you do, you will find they are actually fun to figure out and work thru as you look for issues. Know how the bike should have been wired is also helpful in case a PO has made some bad changes that resulted in problems. You might find when you buy a non-running bike that it was only a matter of fixing someone else's mistake. Just because a bike is wired a certain way when you get it, does not mean it is correct.

Gray smoke sounds strange. Unburned fuel is normally white and that would mean not firing at all and the engine somewhat hot. Black smoke is a overly rich mixture. Blue is normally oil so perhaps what you see as gray is actually blue.

Oil fouling on plugs should be somewhat greasy and heavy versus rich fouling which tends to be evenly distributed and powdery soot.

You say that the smoke gets worse the longer the engine runs. That certainly sounds like oil comsumption to me. If you did not rebuild this engine, you could have bad oil rings, or a broken oil ring. I had a CL160 that ran amazingly well, but smoked like an insect fogger out of one cylinder. I was always amazed that the cylinder even fired. Took it apart and found a broken oil ring. Compression test will not tell you if you have a broken oil ring.

I'm not sure what these engines look like in the head area, but if the oil returns are small and can plug with crud, you might have restricted returns and that is why, as the engine pumps more oil into the head, it has no place to go and comes down the guides causing you to burn oil.

Question here is does it smoke out of both exhausts or just one? If just one, I would lean towards a broken oil ring. If it smokes out of both then you could have worn oil rings in both jugs, worn guides or plugged returns from the head. That of course is all based on the assumption this is an oil burning issue, which I tend to think it is. I've had an engines run with the carbs partially choked due to a cable issue and although it ran poorly, I could keep it running.

I suggest you take your foulded plugs to a local mechanic and ask him to tell you if it is oil or fuel fouled if you do not have the experience to tell the difference. That will point you in the right direction.

regards,
Rob

raindriver · Post by **raindriver** » Thu Dec 13, 2012 8:09 pm

Thanks all for comments!

I am now pretty confident that my wiring and electrics are in good shape. With a new plug I now get a nice fat spark (until I run it, and it fouls, and starts not getting good spark). I have an after-market coil, but it's same spec's as OEM.

Thanks for tips on smoke-colour, Snake. I'm fairly comfortable with 'reading' plugs, which is why I'm having such a hard time with this situation...it's just not what I expect (and, admittedly, I haven't run into many serious problems up to now). The smoke is light-colour, maybe grey or white but not really blue. No oil smell in exhaust, which I've noticed in previous ring problems on vehicles. The plugs are black-carbon, dry, with a smear of black fluid around the bottom of the threads - hard to tell if it's oil or fuel mixed with carbon.

But it sure is sounding ring-ish, eh? I have some time off upcoming and will dive in. More news as soon as I have a look. (Sorry again that this is taking so long, I know a lot of you would've had 'er rebuilt and be riding by now. But I work full-time, and I'm a full-time student, so there's not much time left for the Dream.)

raindriver · Post by **raindriver** » Sat Dec 22, 2012 1:34 am

Continuing the saga...

Got a chance to dig in. Pulled head, cylinders, pistons, rings.

Some scuffing on the pistons, but nothing serious according to what I've read here.

I bought a nifty new digital measurin' stick, which tells me I have (mm)

Left Right
Cyl bore bottom 60.4 60.7
Cyl bore top 59.3 60.0
Piston top 60.2 60.2
Piston bottom 60.5 60.6
Both pistons narrower by 0.2 across pin

Pistons and rings marked '0.75', which I take to mean 3 times over. Geesh, I have a HUGE Dream, I'll enjoy figuring out what that means for my total displacement...I might be nudging 310! Pistons are marked 'ART', which I think somebody said is after-market.

Anyway, everything looks pretty good inside. The wrist (piston) pins are both a bit sloppy laterally (side to side). That, or the overly-tight fit (if my new guage is to be believed), is probably what's giving me scrapes along the pistons. I haven't yet measured end-gap on my rings, so we'll see what that says. But so far, it looks like this was done not many miles ago.

There was some carboning in both sides of head (hey, it's a Hemi!) and on piston tops...but not really much. I've seen much worse in automotive situations. So, subject to a bit more thinkin' and anything you lot might like to comment, I think I'll accept that my 155 psi compression readings were honest, and that my problem lies elsewhere.

Could well be a while before a final resolution to this problem, what with holidays and all. cheers!

G-Man · Post by **G-Man** » Sat Dec 22, 2012 2:27 am

Hi

0.75 mm over means that cylinders and pistons should be around that figure give or take a few clicks in the second decimal place in mm.

Piston should be measured at bottom of skirt at 90 degrees to the pin.

Most cylinder wear will be at the top just below the ring of carbon. You need to get to the second place of decimals with your measuring device to make any sense of the numbers....

G

Honda305.com Forum

ideas on what happened?

doesn't seem to be the rings