Topic: problem child (possible breakthrough)

[number13]

NKG dr8ea plugs in it.  From what I have read this is probably the wrong plug to run.  I think I should swap them out with d7ea plugs or similar.  Does that sound right?

You are correct, use the D7EA, never use a plug with an "R" designation,
that is a resistor type plug made for cars.
Keep at it S-Dog, we'll have out on the road yet!

[edbikerii]

Alright S-Dog.  Sounds like you are well on your way to independence from that "mechanic" of yours.

Woo hoo!

[mlinder]

you need to change to non resistor plugs right away. You are running 'rich' because the spark is weak, due to too much resistance.
D8EA, as others have told you.

[edbikerii]

#1 float valve sounds stuck, too.  First try giving it a sharp rap with a screwdriver handle.  Sometimes that loosens up stuck float valves.

Have you got a shop manual or downloaded one from the links in the FAQ yet?  Look at the carbs FAQ, too.

[dustyc]

Good man.  You're on your way. 

The plugs can tell you alot.  For instance you're partially fouling/running rich on number one and four.  Could be weak coil for 1 and 4 giving weak spark.  Could be so much gas leaking that instead of clean air going in you have raw gas increasing the amount of fuel in the mixture.  Could be improperly set carbs.  Could be 1 and 4 points aren't right.

Set your valves, points, timing.  You'll need feeler gauges for setting valve clearance and point gap.  An inductive timing light is really helpful vs a static light as you can check the advanced timing(2500 rpm and up) as well as the timing at idle.  A battery charger is pretty essential since you'll likely run down your battery several times turning it over and running at idle(it doesn't charge at idle).  A low battery will give you weak spark and the bike won't run worth a crap, so tuning is impossible until you've charged it.

Replace your plugs.  Back to what was stock.  While you have the plugs out, connect a spark plug and touch the threads to the engine and turn the bike over with the ignition and kill switch on.  You're checking the spark.  Hopefully they will all be the same and nice and bright.  If they're not, you can cut a little off the wire and reinstall the cap.  You might not have a good connection there.  Or if it is weak, you may need a new coil.  You can search here and find the procedure for testing the coil if it is suspect.

You'll need rubber o-rings for the T's between carbs.  The bowl gasket should have been replaced in the rebuild.  Here is your chance to see what that mechanic did.  If it's an old gasket, DEMAND a full refund from the guy.   Keep a fire extinguisher handy until you sort this out. 

Order some new points, condensers, an extra set of plugs, the o-rings you'll need for the carbs, and anything else you come across that could use refreshing.

You're going to have such a better relationship with your bike after all this. 

[S-Dog]

I have the Clymers manual and I am getting the Honda(I think) manual for it...
I am completely pissed though.... wrong plugs, the friggen gas leak, I really got it in the shorts..... the only good thing is that I would have had to spend 1k to buy the bike.  I would have rather given that money to my buddy than what looks to be a hack mechanic.

[edbikerii]

No use crying over spilt milk.

If you need the Honda shop manual, it's probably available online here for free.  Check out the "Manuals FAQ" here http://www.sohc4.us/forums/index.php?topic=426.0

For my 77 550 K at least, the Haynes manual is completely wrong when it comes to carburetion.  Be wary of year differences, etc. that may not be covered thoroughly in aftermarket shop manuals.

Check out the Carbs FAQ here http://www.sohc4.us/forums/index.php?topic=5410.0

I have the Clymers manual and I am getting the Honda(I think) manual for it...
I am completely pissed though.... wrong plugs, the friggen gas leak, I really got it in the shorts..... the only good thing is that I would have had to spend 1k to buy the bike.  I would have rather given that money to my buddy than what looks to be a hack mechanic.

[S-Dog]

I think I have a breakthrough... is it my understanding that the float should go up and down without and resistance?  If this is the case then I have found the answer to 2 of my many problems.  I just tore off the 1cyl carb bowl(this is the one that was also leaking).  Sure enough the float was locking at the bottom.... there is something going on with it.. once it goes up a little bit it is free as a bird.  This probably is causing my leak in the gasket, my wet plug and backfiring.... WOOHOO.. I hope someone can confirm my newbie diagnostic.   


As a side note... The inside of the carb that I could see is SPOTLESS.... the carb looks like it was taken apart and soaked.....

[edbikerii]

I think I have a breakthrough... is it my understanding that the float should go up and down without and resistance?  If this is the case then I have found the answer to 2 of my many problems.  I just tore off the 1cyl carb bowl(this is the one that was also leaking).  Sure enough the float was locking at the bottom.... there is something going on with it.. once it goes up a little bit it is free as a bird.  This probably is causing my leak in the gasket, my wet plug and backfiring.... WOOHOO.. I hope someone can confirm my newbie diagnostic.   


As a side note... The inside of the carb that I could see is SPOTLESS.... the carb looks like it was taken apart and soaked.....

Yeah, exactly why rapping it with a screwdriver sometimes frees it up!  The float valve may just be all crudded up with varnish (2 of mine were).

If you are SUPER CAREFUL, you might be able to clean it up in place.  It is very tricky, though.  Might want to look at the manual once or twice to get familiar first.

Things will fall out if you slide out the float pin, so expect it and be EXTRA CAREFUL.

[edbikerii]

Also, don't scratch up the rubber tip of the float valve.

[dustyc]

See if there is something binding it like a burr on the pin.  If it was removed with pliers, they could have marred it.  You can take some fine sandpaper to the pin to smooth it out. 

If the carbs are spotless, I doubt it's old gas residue causing it to stick.  You never know though. 

[edbikerii]

Yeah, you shouldn't use pliers to slide the float pin out, either.  It is held captive by the float bowl, so it should slide out sideways rather easily, unless somebody has already bodged it, or if it is stuck in with varnish.

I'm thinking that your mechanic just cleaned out those float bowls, but didn't give the tricky stuff any consideration.

[Raul CB750K1]

Yeah, you shouldn't use pliers to slide the float pin out, either.  It is held captive by the float bowl, so it should slide out sideways rather easily, unless somebody has already bodged it, or if it is stuck in with varnish.

You sure? I always thought it was the other way round, the pin would be held captive by the carb body pillars and the float assembly would rotate freely in the pin. Actually, in one of the last I rebuilt one of the pins was so loose that it would get out by itself from the pillars and the float assembly, I had to slightly chamfer one of the ends to make it a tighter fit inside the carb pillar.

[edbikerii]

Yeah, the pin is supposed to rotate freely, but it is held "captive" when the float bowl is installed, so it won't slide out and let the float free.  There's no need to make it a tight fit in the pillars.  Just make sure it is in the right place loosely when you put the float bowl on.

At least, that's how it is on my bike.

Yeah, you shouldn't use pliers to slide the float pin out, either.  It is held captive by the float bowl, so it should slide out sideways rather easily, unless somebody has already bodged it, or if it is stuck in with varnish.

You sure? I always thought it was the other way round, the pin would be held captive by the carb body pillars and the float assembly would rotate freely in the pin. Actually, in one of the last I rebuilt one of the pins was so loose that it would get out by itself from the pillars and the float assembly, I had to slightly chamfer one of the ends to make it a tighter fit inside the carb pillar.

[S-Dog]

I think I am going to make him(the mechanic) do it.  He needs to redo his lines and make sure that that float slides correctly... He also needs to put the correct spark plugs into the bike.... I really would hate to screw it up more than he has already and then be out the money AND a bike.

I am also curious to see what he is going to say when I tell him. 

[edbikerii]

I think I am going to make him(the mechanic) do it.  He needs to redo his lines and make sure that that float slides correctly... He also needs to put the correct spark plugs into the bike.... I really would hate to screw it up more than he has already and then be out the money AND a bike.

I am also curious to see what he is going to say when I tell him. 

Yeah, at least you've got a bit of an education, so he won't easily dismiss your concerns.  In my opinion, both the sticky float issue and the leaky fuel line issue should have been covered by his rebuild.

[dustyc]

I wouldn't let him touch it again.  That's just me. 

[Raul CB750K1]

Yeah, the pin is supposed to rotate freely, but it is held "captive" when the float bowl is installed, so it won't slide out and let the float free.  There's no need to make it a tight fit in the pillars.  Just make sure it is in the right place loosely when you put the float bowl on.

At least, that's how it is on my bike.

Yeah, you shouldn't use pliers to slide the float pin out, either.  It is held captive by the float bowl, so it should slide out sideways rather easily, unless somebody has already bodged it, or if it is stuck in with varnish.

You sure? I always thought it was the other way round, the pin would be held captive by the carb body pillars and the float assembly would rotate freely in the pin. Actually, in one of the last I rebuilt one of the pins was so loose that it would get out by itself from the pillars and the float assembly, I had to slightly chamfer one of the ends to make it a tighter fit inside the carb pillar.

If my memory serves me I recall the pin is usually a little chamfered in one of the ends, so you should press it out from the other end. And I'm talking about CB750, CB350 and even XS400 carbs. In all of them, even when I disassembled them, the float assembly rotated freely while the pin was fixed. What is more, I never touch the float assembly hinge and after reassembly all of the float assemblies, with the pin "locked", rotate freely, to the point to easily check float height and all. I would like to read somebody proving me wrong because otherwise the time has come to remove some carbs in my bikes.... ;-)

[edbikerii]

I wouldn't let him touch it again.  That's just me. 

Yeah, that's a good point, dustyc.  He's already demonstrated his incompetence and his lack of regard for your safety, letting you ride around on that bike with gas leaks.

[edbikerii]

Raul, I'm not trying to prove you wrong at all.  I just went and looked at one of my spare carb sets, and sure enough, in the float bowl there are two protrusions that extend to either side of the float pin, outside the pillars, that retain the float pin.  It makes no difference whether the float pin spins freely or not.

I don't think there is any harm in making the pin fixed, as long as the float can rotate freely about it, but there doesn't appear to be any benefit to fixing it.

Granted, I'm not a Honda tech or anything.  I just stick with what works for me.

Yeah, the pin is supposed to rotate freely, but it is held "captive" when the float bowl is installed, so it won't slide out and let the float free.  There's no need to make it a tight fit in the pillars.  Just make sure it is in the right place loosely when you put the float bowl on.

At least, that's how it is on my bike.

Yeah, you shouldn't use pliers to slide the float pin out, either.  It is held captive by the float bowl, so it should slide out sideways rather easily, unless somebody has already bodged it, or if it is stuck in with varnish.

You sure? I always thought it was the other way round, the pin would be held captive by the carb body pillars and the float assembly would rotate freely in the pin. Actually, in one of the last I rebuilt one of the pins was so loose that it would get out by itself from the pillars and the float assembly, I had to slightly chamfer one of the ends to make it a tighter fit inside the carb pillar.

If my memory serves me I recall the pin is usually a little chamfered in one of the ends, so you should press it out from the other end. And I'm talking about CB750, CB350 and even XS400 carbs. In all of them, even when I disassembled them, the float assembly rotated freely while the pin was fixed. What is more, I never touch the float assembly hinge and after reassembly all of the float assemblies, with the pin "locked", rotate freely, to the point to easily check float height and all. I would like to read somebody proving me wrong because otherwise the time has come to remove some carbs in my bikes.... ;-)

[S-Dog]

I understand your point.... and if I had a lot of time and confidence I would do it myself. However I do not have much of either.... That and the thought of laying out even MORE money to fix HIS mistakes drives me insane.

[edbikerii]

Sorry Raul, I can't help myself sometimes, so I went and checked the Honda service manual for the CB500-550.  On page 60 it says simply "Pull out the float arm pin and remove the float."

The picture, figure 181, shows the tech sliding the pin out by hand.

Page 61 under "Reassembly" says simply to "Install the float".  There is no mention of any chamfer, or fixing the pin, or using any tools to remove or install the float pin.

I still don't see any reason NOT to fix the pin, as long as the float can rotate around it freely, but it isn't necessary.

And for all I know, the procedure is different on the bikes you've mentioned.

[TwoTired]

Cb750s are supposed to use D8EA.  Non-resistor, unless you have changed the stock resistor caps for non-resistor.  Then a resistor plug is appropriate.

Cheers,

P.S.  The float bowl pin is held in place with bosses molded on the the float bowl itself.  Marks or pin deformities are from work done after it left the factory.

[Raul CB750K1]

Thanks for the input Ed and TT. I always needed a small screwdriver to push the pin out, and even when it was not too hard, my impression was that the pin was retained in place by the carb body not the float assembly.

Now that I tink about it, the only way that the carb body would retain the pin would be that the hole diameter would be slightly smaller than the pin diameter, or that the pin end would be flattened so it would stay inside the hole. In this way, after a few rebuilds the hole could get enlarged and there would be no easy fix. While if the float assembly retains the pin, it is a simple as slightly bend it....


My bike's carbs have been working well until now but sure enough I will check the float assemblies when the time comes.


Now back to the original thread, if I were the mechanic you talk about and would have done something wrong like this, either I would assume I was right or if I discover I was wrong I would try not to work on the bike again for free. That's the great thing about working on your own bikes: as the reward is not the pay but the peace of mind, we don't cut corners when it comes to time. Actually, the text in my signature is from "Zen and the art of motorcycle maintenance" and it was the part that I couldn't agree more when I read it.


Sorry for the thread hijack. If I were you I would force that guy to fix your bike right regardless of how much time it takes -your money didn't leak gas and he doesn't know how much time you needed to make it- and get yourself some tools and a couple manuals to start making your own maintenance.


Raul


Raul

[TwoTired]

Thanks for the input Ed and TT. I always needed a small screwdriver to push the pin out, and even when it was not too hard, my impression was that the pin was retained in place by the carb body not the float assembly.

Perhaps we have a terminology problem.
The float bowl is the cover you place on the carb body to enclose the float bowl cavity.  The float "assembly" does not retain the pivot pin. Neither does the pin post molded from the main body.  In the float bowl "cover" you will will find that it narrows where the pin is oriented when installed.  It is narrow so that if the pin does move from vibration, it will hit the bowl "cover" bosses to limit any lateral movement.  Thus, the pivot pin is allowed to float.  I've seen pins that were flattened at the ends, as well a ridge marks from being pinched by pliers from field mechanics.  But, on factory undisturbed carbs the pins were cylindrical and smooth.

Look in the float bowl and imagine where the float pin would be when installed.   You'll then see the limiting bosses.

For S-Dog. 
It is worth a try to get your mech to correct his shody work.  He may well give you grief, instead.  He has demonstrated incompetence, malice, or thievery tendencies.  It seems likely he will continue to do so, however.

You could check with the Better Business Bureau to see if any complaints have been filed. Actually should have done his before contracting for service.
If he won't correct his work, DO file a complaint with the BBB.  They will at least call him and let him know that watchful eyes are paying attention.  And, he may be more interested in customer satisfaction for future encounters.

cheers,