Ugly Betty Lives!...barely.

[Gyrogearloose]

Well, after doing the Octopus thing, and removing and cleaning a petcock, and charging the battery,...and doing a compression check (all 160's)..I decided to see...you know,..IF..she would start. She did, but, Oh, missing badly. The PO had said he thought #3 had valve problem, so while she sat there, "Put put put", I pulled #3 wire. It changed to worse. OK, try #4. Same, worse. Then I went to #2, and got shocked!..repeatedly. Duh, put wire back on. Well, I shut her miserable -ss off, and felt for pulse..er, felt her pipes. Huh. No's 3 & 4 were hot. No's 1 & 2 not. Oh, and leaking gas out of #4 in the air box. That soon quit. Both petcocks in the "On" position. Well, good folks, it's 9:45 (that's PM), and I'm giving up a bad job. Well, it feels like it. Could the Octopus be wrong? Both outside nipples with a "Y", and going to front of pectcocks and down to carbs 1&2, then 3&4. Both outside nipples going straight to the rear of petcocks. Is it a no gas for 1 & 2? What about the shocks I got from &2 when I pulled the spark plug wire?..I'm fried for tonight. Will try to sleep on it, and maybe get an inspiration or solution...or...read past threads when I wake up a get CLUES... Yes! I'd really appreciate any suggestions. Thanks.

[Crazcnuk]

Your lucky, I got shocks from all 4 when I tried that!

Haven't tried since I replaced the spark plug boots.

I believe (experts here will correct me) That 1&2 not working indicates a fuel issue.

I would check to see that you don't have a plugged or kinked hose going to the 1-2 tee, and that the vacuum valve is letting fuel through to that side.

Try putting the petcock on the 1-2 side on prine, then see how it runs, as that should bypass the octpuss.

Oh and if you have 160 compression on all 4, you can't have a valve problem!

[oseaghdha]

The octopus will send fuel everywhere, even if one petcock is off. It has to because there is only one valve on it.

The only thing that matters is that the prime goes to a 'tee' connector. The prime is the front nipple on the petcock, so you're ok there.
Pop the bowl plugs to see if you got fuel in 1 and 2.

If you have fuel, that leaves ignition. Maybe a bad plug or wire/boot.

[AlanB]

Hi Gyro,

One coil fires 1+4 together, Other coil fires 2+3 together. fuel lines feed 1+2, or 3+4.....no fuel link between 2+3

Therefore, it is usually a clue to which system is giving problems..........

However, it is not absolute; only a pointer!

Check to see if there is fuel in 1=2, if so, treat it like it was flooded; take the plugs out, spin the motor over, put the plugs back (Might as well check for sparks when they are out!) and try again!

If you are sure that 1+2 are getting fuel, but they don't run, get the engine warm on 3+4, then stop the motor and swap the plugs around; put the hot ones in the cold cylinders, and vice-versa........ hot cylinders should still go with the cold plugs, and hot plugs might be enough to start the flooded 1+2.......

After you get it going, you will need all new plugs; I don't know what it is about modern fuels, but if plugs get saturated with it, they seem to never really recover..... And will always cause starting problems.

AlanB

[Gyrogearloose]

Hey, good morning Alanb. Ugly Betty had new plugs just before the test firing last night. After sleeping on it, I think the carbs need cleaning and adjustment. I emptied the tank and found paint chips and rust specs in the fuel. But it still stumps me finding 1 &2 cold after the test run. Coincidence? I did have a problem with the octopus, however, (it's a tight fit under there.), I don't think anything was kinked. It's a wet a.m. here, and farm chores take priority, but they're finished and I should be out in the shop shortly. I did notice last night (had the timing cover off), that the disk with the marks on it was rotating kinda' crooked? Thanks for the replys guys!

[oseaghdha]

Originally posted by AlanB


fuel lines feed 1+2, or 3+4.....no fuel link between 2+3

...................................

.....................
AlanB

Not true if you have the octopus installed and it is running.

I just put mine back in and studied how its hooked up. There is a single valve connected to the diaphragm. Both inlet lines share a common manifold, therefore you can feed all four carbs on one petcock.

The "TEE" connector is basically a short circuit. You do need both "Primes" on to fill the bowls if they have been drained. In that case, what Alan said is correct.

Something just occured to me. Do you have 1 and 2 plug wire switched around?

[Gyrogearloose]

Well, had time to do a little testing. I have all new plugs, so when I pulled #1, it looked like there was fuel on it's tip (and smelled like it), so I think it's getting gas. Anyway, tried another start with petcock on PRI. same. Queer happening as I choked it to get it running then sw to "on". Seemed like no matter what I did, it would progressively get worse and then die. Here's the queer part: the last sound would be a starter-like noise dying. Like maybe the starter had stayed engaged all along? I dunno, and then gas running all over, especially out of #4. ? The air box bottom, and filter, never were on there, so I'm looking from underneath to see where the fuel is coming from. I'll have to go to a diagram to see what that's made up of, as I felt up there and was surprised to find some kind of tube ? going into #4 (and yes all of the rest of them). Huh. Yup, I'm a first-time "XSer", and just, heh, feeling my way around. Thanks for your help.

[John]

The fuel was running out of the airbox intake boot that attaches to the carb. Which ever boot has fuel leaking from it, then that carb is flooding. That is a common occurance, I have found, when filling a set of dry bowls. It seems because of the floats hanging to their full extent, sometimes the float needle will cock in the seat and will not allow the floats to rise and close off the fuel supply. Usually a few raps with a hammer handle on the carbs, turning off the fuel, and starting the bike will be enough vibration to allow the needle to unstick, and allow the floats to close.
The dying duck sound is that of the starter clutch. It is engine driven, and sometimes can make an odd noise or two. The clutch is an over riding clutch style and it disengages from the starter when the engine starts. The starter doesn't stay engaged unless the starter clutch is not releasing.
One more thing...get rid of the octopus. Run a fuel line from a pectcock to the set of carbs on the opposite side of the bike from that petcock. Do the same for the other petcock. You will have to turn the fuel on manually, but you have positive control that way. Just use the rear nipple on the cocks, and cap off the front nipple. It is for prime, and will not be needed once you eliminate the octopus. The fuel will flow in the run position.
The tubes you found going into each boot was just the crankcase vent system. The large hose that is attached to the crankcase at one end, and the top of the aibox at the other, is connected to these four tubes.

[TopCatGr58]

Hey Gyro,

Like John said, toss out that Octopus IF you've verified that it's not working right!

But, IF you haven't cleaned the carbs, then that should be your next step! Also, get some inline filters to install once you get them rebuilt, otherwise that rust...and it's rust chips you're seeing coming from the tank, not paint chips that are getting down the line and can cause more problems, like sticking float needles and such!

What's suprising is that you said #4 carb was leaking, but it's was one of the two that was actually firing! When a carb is flooding, it usually will be the one that is not firing, too much fuel vs. the other cylinders! You may have fuel in the bowls, but if the pilot circuits are clogged, as well as the enrichener jet that sits down in the float bowl, then it's very tough to get the fuel into the cylinders properly! Although you stated that there was fuel on the spark plugs for #2!

So....you had fuel, and had spark....you got shocked....but that could actually be a problem. IF the insulation has broken down in the wires, then they could be grouding to the engine instead of running thru the plugs!? With these dual plug wired coils, they actually run from one plug wire, thru the spark plug, the engine, and then back to the other plug, cap, wire and back to the coil! How is your battery power? An Xsive reported problems with a pair of cylinders not firing that were NOT linked together electrically, like yours....1-2 instead of 1-4 or 2-3, which made him think fuel! But IF the battery is weak, or not enough power is getting to the ignition coils, then the spark generated is only strong enough to fire the primary spark plug, but not the return plug!

If you have a multimeter, check the coils, the plug caps, for proper resistance(s). Same for the primary windings. The plug caps have built in resistors and they and their connections can corrode, break down....the caps actually come apart, unscrewing from the plug end! Cap resistance should be 5-8kohms, coils without caps ~ 15kohm, primary 1.5 ohms if 78-80, ~3.0 for 81...forgot to see what year yours was before posting!

A wobbly outer timing plate is not necessarily that bad, since the pickups and such are attached to actual inner timing plate that is connected to the vacuum advance. The outer plate is just the timing indicator/degree marked plate, and they can sometimes get bent, but not a big thing. It's the inner base plate that you want to be sure is moving smoothly!

[AlanB]

Hi Guys,

I am with John; At least until you get it going, eliminate the octy; it is another variable which you do not need.
Once it is all sorted out, you can decide if you are bright enough to remember to shut off the fuel, or if you need an unreliable mechanism to (sometimes!) do it for you.

The easy way to cap off the "primes" is to join 'em with a piece of pipe.

If you are new to fours, the comment on plug leads is worth checking; 3+ 4 are obviously going to the right place. the other lead from the coil which feeds 4 goes to 1. the other lead for the coil feeding 3 goes to 2.

Keep in touch!

AlanB

[Gyrogearloose]

Thanks John and TC, those are some good tips. Oh, I love it!! Get rid of the Octopus! I'll do that for sure. I think,too, that the #2 wire is probably broken down. Earlier on I tested ea cyl with a new plug, and they did seem kinda weak on spark..like light blue, and not very snappy as I recall. I was surprised to find #'s 1&2 pipes cold to the touch after the test runs. I'll do all the electrical tests I can before cleaning the carbs, because that might be somewhat of a challenge. Oh, and Ugly Betty is a 79 SF; the PO painted EVERYTHING flat black, turned the headlight upside down, did away with the inst. lights, the tach, and left the ignition sw dangling. No front fender, no seat, and had tried to isolate #3 cyl from fuel as he reported it had a valve problem. So the Octopus came under the knife and pliers, and there seemed to be open fuel lines here and there under the tank. The battery is a year and some months old but took a charge and held it real well. Ok. Thanks again. I'll have another go at it. WE may get this old bird back on the road yet! Wet and windy here on Whidbey Island, WA.

[Gyrogearloose]

Well, I did have another go at it. I tossed the octopus, and rapped #4 carb with a hammer handle (literally). I checked coil wires to each cyl. OK. I set petcocks to "on", and cranked her over. Battery is good. Anyway, she started...ha, like running on #3 only! I started pulling plug wires (#1, then #2, finally #4), and it didn't make much difference. Slight difference on 1 & 2 (sight detonation and rpm's) and none on #4! I'm running around like a chicken...so I revved it up a bit. Ha! #4 came alive. I felt pipes. 1 & 2 still cold, and 4 getting warm. Oh, and backfiring at this time (after 4 comes alive). Time to shut'er down. I couldn't tell where backfires come from?..maybe 1 or 2? I pulled 1 & 2 plugs. Barely any gas on them, only on the very tip...a dark smear. ? So, could the PO have messed with idle screws? or idle mixture adjustments? One last chance here, is there anything short of dirty carbs (1 and 2) that stops the fuel? I did get a buzz pulling the wire on 2. If not, it'll be a while before I surface again, as I'll be doing the carb cleaning chore. "Oh, woe is me". Thanks again guys.

[AlanB]

Hi Gyro,

Sounds like you have nailed it to fuel!

First step is just to check that it is running out of the petcock on that side when turned to "ON".... (or reserve, or whatever!) If it ain't coming out of there, It can't go anywhere else!

Then check that it is arriving in the float bowls; I think all versions of the carbs have some sort of drain plug/screw in the float bowl; drain it, turn on the fuel for a minute (or so!) and then open the drain again and make sure it had refilled.

When starting "cold", fuel should be coming from the choke jet. This should put out enough that all the other circuits are pretty irrelevant. The choke jet lives in a deep recess in the bottom of the float bowl, so they are often the first thing to block, and are easy to miss, if you do not know they are there. Do 'em first.

You are looking for a little brass (non-removable!) jet at the bottom of a hole!

Keep in touch, Gyro!

AlanB

[Gyrogearloose]

Thanks AlanB. If checking for the choke jet, do I have to take the float bowl off? The drain plug for my 79SF must be that bolt head right at the bottom of the bowl?..I think so. I'll open it up and see what comes out. Blustery Sunday here on Whidbey Isl. WA. 0930hrs. Thanks again for your help.

[TopCatGr58]

Hey Geno,

Yes, you have to remove the float bowl to access the enrichener jet, there's a tube in the bowl, and cleaner should flow thru that tube and out the jet opening, may require a fine piece of wire to dig around in there to dislodge some heavy gum/varnish and debris!

Since you don't have a manual, you can go to
The Official Yamaha Online Parts Fiche site , and just select the button on the right, then motorcycle, year, model and you can view exploded views of all of the systems on our machines, might be helpful!

Another problem can be vacuum leaks, like where the carb boots mount to the engine, as well as the boots themselves, which could prevent it from being able to suck the fuel thru the carb effectively.

If you haven't done so, you will want to look thru the tech tips for the carbs, to see info about what to do and not do when working on these carbs, like NOT soaking the entire carb body in carb cleaner=damage to the butterfly shaft seals!
T.C.