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Discussion Starter · #1 ·
Hey guys. Thanks for the advice on the WOT hesitation problem. Unfortunately, my problems are just beginning here. The other day, I switched the gas caps back to the old ones to see whether the new caps were not venting properly. The bike ran worse at WOT. It seemed to be running great, but around 85mph, about when the secondaries should be kicking in, I lost power. Feels like starving for gas. Other than that, it was running good.

Saturday morning, I was getting ready to take it over to get inspected. She wouldn't start up. Finally got it to start by holding the gas all the way open. Lots of black smoke "brapping noises" and couldn't get it to stay running at all. I figured that I had fouled plugs. Since I haven't changed them since I bought the bike, almost two years ago, I figured it couldn't hurt. So I took the plugs out. One of my wire boots on the number 8 cylinder was white at the corner and very thin. So new wires seemed to be in order too. I put in Bosch platinum plugs and new 8mm wires. The old plugs were very black and sooty looking.

When the job was finally done, one set of headers, on the waterpump side, wasn't completely sealed. I torqued them down more, and almost have that problem resolved.

I fired up the bike and now it backfires when I rev it up. The backfires come when the motor begins to slow down after a rev. I took it for a ride and it doesn't want to stay running, the engine is fumbling and the wheel is trying to stop at times, as if the engine doesn't want to turn.

I am wondering if my Q jet is screwed up now and if this was possibly the cause of the high end boggind down at WOT previously.

I need help. Any one that wants to can call me or write.

Phone is 315-452-7020 / cell is 439-9593

I am thinking of taking the radiator off and checking the timing now, but the only timing mark is a "0" and I am not sure which way to change it to get 14 degrees. Also, how to measure 14 degrees.
:oops:


Thanks
 

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Hoss,
Since all this seems to have started after you changed the dist cap & rotor, then you changed the wires and now it's even worse, are you absolutely sure you have the firing order correct?? Firing order is 1-8-4-3-6-5-7-2. Sounds to me like you may have something mixed up. Worth a look.......Don B
 

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Hoss,
Cylinder arrangement is, starting from the front of the engine: Left side, 1 3 5 7. Right side, 2 4 6 8.........Don B
 

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Hoss,

I'm no expert here but the backfiring seems like it could be timing (actual timing, plugs, wires) related to me, too.

Chris
 

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Hoss
If your plugs were black and sooty...fuel starvation is certainly NOT your problem. I wonder if your secondaries aren't stuck open or if the small spring which holds them closed isn't working either because it is broken or the set scew Torx) hasn't backed off. If this is the case the secondaries will open erratically and far too prematurely. Lift the rear of the tank a little and prop it up. The spring that holds the secondaries closed can be seen near the rear of thr right hand side of the carb. You'll have to mave the linkage a little forward to see the adjustment screw. Move the little tab that opens the secondaries. It shoul open them with slight resistance and should close when let go. If not, turn the scew clockwise 1/4 turn or so, and check to see that the secondaries close. Hold the screw in that position and tighten the set screw(#10 torx). Try the motor. If you've overdone it nothing bad will happen except that the secondaries won't open but the bike should run fine. Just a thought.
Use a timing light with which you can set the degrees of advance in the light and turn the distributor until the mark lines up with the pointer.
If Don's suggestion was correct and you mis-connected the plug wires, the motor would have never run properly at any speed at all so I doubt that's your problem.
I would ask Neil Weber or Bob Gamel for help on the other sites. They know EVERYTHING!
Good luck and let us know. If all else fails, truck it to a good dealer.
Joe
 

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"I fired up the bike and now it backfires when I rev it up. The backfires come when the motor begins to slow down after a rev. I took it for a ride and it doesn't want to stay running, the engine is fumbling and the wheel is trying to stop at times, as if the engine doesn't want to turn. "

Hoss, (& Joe)
This statement is why I'm suggesting firing order. Usually to get a backfire, through the exhaust, there has to be either a spark occuring when a piston is on the exhaust stroke, or there can be a "hot spot" on the piston, usually from carbon buildup in the cylinder. It could be timing, but I don't think that's been "fooled around" with yet. The fact that now the wires have been removed and replaced on the dist cap twice, makes me think it's worth a look. If I recall correctly, this all started when the dist cap and rotor were changed :?:
Joe, this must be what it's like when a patient wants you to diagnose over the phone eh!
 

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Is the backfire from the intake or the exhaust?? You mentioned something about a problem with a header.... If you have an exhaust leak, your engine will pull cold air into the exhaust on decelleration giving you a backfire. I recently had a collector gasket blow... backfired out of the exhaust when I let off. Something to keep in mind.... Your backfire may not be related to your performance problem.
 

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TJ,
You're right! A leak at the exhaust manifold gasket could give a backfire!
You guys in Cal are having quite a heat wave eh!!
 

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Discussion Starter · #9 ·
Boss Man said:
Hoss,
Since all this seems to have started after you changed the dist cap & rotor, then you changed the wires and now it's even worse, are you absolutely sure you have the firing order correct?? Firing order is 1-8-4-3-6-5-7-2. Sounds to me like you may have something mixed up. Worth a look.......Don B
Don, I checked the firing order yesterday and it is correct. Just as you listed it here.


If it is the carb, then I can't really time it can I?
 

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Discussion Starter · #10 ·
TJzz4 said:
Is the backfire from the intake or the exhaust?? You mentioned something about a problem with a header.... If you have an exhaust leak, your engine will pull cold air into the exhaust on decelleration giving you a backfire. I recently had a collector gasket blow... backfired out of the exhaust when I let off. Something to keep in mind.... Your backfire may not be related to your performance problem.
TJ, You may have something here. The reason that the header was not sealing properly is because when I had the headers off I took the opportunity to fix another problem. The left side exhaust on my Nascar pipes attaches on the right side to my bell housing. The bracket was broke and I had a guy weld a couple of washers on there so that i could hook it up again. After I did that, the header did not want to go back on. I forced it, but still have a small leak on the middle two ports.
I may have to go back and remove the bolt holding the exhaust pipe and get the header sealed good. The pipes don't seem to need the extra support all that much anyway. I have been riding this way since I had the bike.

Hoss
 

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Discussion Starter · #12 ·
Don, The bike was running great with the exception of bogging down at WOT around 85mph. If the wires were crossed, etc. It shouldn't have run so well, correct?

I am hoping that TJ was right about the leak on the header. I will fix that tomorrow.

Thanks for the help. Hossman

I am also going to check out the secondary spring that Joe suggested looking at.
 

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Hoss , if all these problems happened right after you installed the new dis. cap and rotor . is it possible that you didn't seat the rotor or cap properly and maybe the cap got cracked or something of this nature ? This has been known to happen .
 

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Hoss,
If you`re bike is running great except for wide open throttle I would look closely at the carb as Joe suggested. If it were timing you would feel it alll the time. too much advance and it should ping under load. too slow it should run sluggish. sounds more to me like you have a problem with your secondaries.
 

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Hoss,

Ask Wag about the backfire & bog.......he had the same issue and it ended up being a bad exhaust gasket on the header........slipped down while he was reinstalling them.....

I'd get a new set of gaskets and install them before you start anything else. Simple rule....try only one thing at a time to remedy the problem to make sure you isolate it.

Just my $.03 worth.

Tim
 

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Discussion Starter · #16 ·
GRUMPY said:
Hoss,

I'd get a new set of gaskets and install them before you start anything else. Simple rule....try only one thing at a time to remedy the problem to make sure you isolate it.
I took the exhaust support bolt back out of the bell housing and put on a new gasket. Sealed up good. She started up and it is no longer backfiring. I have to take it for a ride and see how she is acting on the road.

So far so good.

Thanks,

Hossman
 

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Discussion Starter · #18 ·
Backfire is gone.

Took it up a few blocks and she started acting up again. Once it started to warm up, it didn't want to go. Stalled out on me a couple of times. Bike was shaking when I let the clutch all the way out. I had to ride the clutch to get her to go. Eventually she crapped out on me. I had to push it two blocks to get it back home.

I will be examining the carb tomorrow.
 

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I posted this on the Yahoo site as well.........

Subject: Re: Fuel Pump


--- In [email protected], "Rich Lickfield"
<[email protected]> wrote:
> I am prepping my bike for the riding season and I have found that
my
> fuel pump seems to have **** the bed. What pumps do you guys
> recommend? I am looking at a Holley Red and a Carter so far.
>
>
> Hossie


Hoss, This was your original post after which, everything started to
happen.......Yes??
Why did you say that your original pump had "**** the bed"? What were
the symptoms then? Was it leaking fuel, was it not pumping fuel,
would the bike run at all?
 

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Hoss,

When it started to die out, did you loosen the fuel cap?? Sure sounds like it's building a vacuum in the tank or the line is blocked somewhere.

Possibly there is something in the tank blocking the petcock screen. Turn off the fuel and diconnect the line at the petcock, add a piece of drain tube and put LOW air pressure into the petcock to back flush it. If you have a Pingle with reserve, put it on reserve and see if it solves the problem.

Tim
 
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