Author Topic: I'm not going to give up on her!  (Read 2507 times)

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Offline Anghil

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I'm not going to give up on her!
« on: March 06, 2012, 02:20:21 PM »
Since I've bought this bike, about a month ago on craigslist, I've been running into one problem after another. (despite the previous owner swearing all was well. It did run when I bought it.) A few days after the purchase, it decided to cut out on me. We traced the problem to some faulty wiring. Next, I had to replace the clutch lifter rod, clutch adjuster and clutch lifter mechanism. Now it won't start up again! >:( All plugs are getting spark and fuel is getting to the carbs. I'm thinking it may be a mixture issue, but as a neophyte to mechanical work I'm in no position to say what's what.

When I press the electric starter, it sounds like it wants to go, but when I open the throttle even a little the sound changes and stops chugging. Not sure if this video is of any help but you can hear the change when I open the throttle.


http://www.youtube.com/embed/_Xd9zVvOAtU
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Offline cmonSTART

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Re: I'm not going to give up on her!
« Reply #1 on: March 06, 2012, 02:29:26 PM »
Well, sounds like at least one cylinder is trying to go.  Is the choke working? 

Personally, I would give it a very light spritz of starter fluid (ether) into the intake and see if it kicks over and starts on that.  If it does, you know it's most certainly electrical or mechanical. 
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1978 CB750F Project

Offline cmonSTART

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Re: I'm not going to give up on her!
« Reply #2 on: March 06, 2012, 02:30:04 PM »
And be careful with that stuff!  A little at a time!
1981 GL1100 Interstate
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Offline nccb

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Re: I'm not going to give up on her!
« Reply #3 on: March 06, 2012, 02:59:54 PM »
+1 on checking the choke linkages.

I had this issue this winter and it would take 30 or 40 minutes to get it to finally start.  Mine sounded just like that, I just needed to replace the pins holding the linkages together and found some real some cotter pins that did the trick.

Offline paul_C

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Re: I'm not going to give up on her!
« Reply #4 on: March 06, 2012, 03:16:19 PM »
Make sure your ignition points are gaped properly! my bike last summer gave out on me, i gave up on her and then checked the points. they were pitted and gapped incorrectly. This will still give you spark to your plugs but its spark at the wrong time and in the wrong place. Fuel, Spark (AT THE RIGHT TIME), compression.

Give it a shot.

Offline scottly

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Re: I'm not going to give up on her!
« Reply #5 on: March 06, 2012, 04:50:10 PM »
1+ on checking your points/ignition timing; the timing sounds like it may be retarded in the video. (Retarded means the spark is happening later than it should)
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Offline grcamna2

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Re: I'm not going to give up on her!
« Reply #6 on: March 06, 2012, 09:55:51 PM »
If it was mine..I would drain all the carburetor bowls and re-fill the tank w/ known Fresh Fuel along with all the other things that have been previously mentioned.  :)
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Offline Chachi

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Re: I'm not going to give up on her!
« Reply #7 on: March 07, 2012, 06:19:11 AM »
Your situation is similar to one I had a few months ago. My bike came from a good home, but it had not been ridden much in the last 15 years. I developed a cutting out/starting issue a few weeks in to owning. My symptoms would show up when the tank was not full. If fuel level reached half or lower, bike would cut out and not start. If I filled the tank up, it would do ok.

My issue was fuel flow coupled with carb problems. I like what grcamna2 says. Drain bowls and check out what's in there and fill with fresh fuel. Also check out the petcock bowl. Are there inline filters? Mine was solved with a new petcock and a carb rebuild.
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Offline Duanob

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Re: I'm not going to give up on her!
« Reply #8 on: March 07, 2012, 08:46:03 AM »
We've all been there, don't give up! Trust me you will find lots of other stuff to fix before it's road ready and plenty of stuff after that. It's a test of wills between old CBs and man. Most of us triumph, but we are a stubborn lot!  ;D
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bollingball

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Re: I'm not going to give up on her!
« Reply #9 on: March 07, 2012, 10:39:43 AM »
Well, sounds like at least one cylinder is trying to go.  Is the choke working? 

Personally, I would give it a very light spritz of starter fluid (ether) into the intake and see if it kicks over and starts on that.  If it does, you know it's most certainly electrical or mechanical.

I would think if it starts with ether it would be a fuel delivery issue. But still do a complete 3K tuneup. I would think the slow jets are pluged.

                                            Ken

Offline cmonSTART

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Re: I'm not going to give up on her!
« Reply #10 on: March 07, 2012, 05:57:26 PM »
Well, sounds like at least one cylinder is trying to go.  Is the choke working? 

Personally, I would give it a very light spritz of starter fluid (ether) into the intake and see if it kicks over and starts on that.  If it does, you know it's most certainly electrical or mechanical.

I would think if it starts with ether it would be a fuel delivery issue. But still do a complete 3K tuneup. I would think the slow jets are pluged.

                                            Ken

Yup, you're right.  Typo on my part.  Should be "doesn't"
1981 GL1100 Interstate
1978 CB750F Project

Offline Anghil

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Re: I'm not going to give up on her!
« Reply #11 on: March 08, 2012, 11:11:19 PM »
Thanks for all of the advice! A few things I can add: I've drained the bowls multiple times, they are extremely clean, and the fuel in the tank is fresh, I did try spritzing the intake with starter fluid but it was a no go. Sounds like it's time to borrow a neighbor's timing light. One other thing to note is that if I leave the petcock in the open position, eventually fuel will start coming out of the drain tubes attached to the bowls. Is this contributing to the problem and is this supposed to happen? (floats set too low?)
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Offline Hush

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Re: I'm not going to give up on her!
« Reply #12 on: March 08, 2012, 11:28:52 PM »
No, this is completely normal though it was not designed to be like this, just learn to turn the gas off when you stop the bike. :)
I would say this bike is finally getting ridden and the problems are developing from being used (as it should be) so you will just have to cure them all and once done keep riding it, bikes left in the garage sulk! ;D
I'm making a guess at a few blockages in you carb jets, the first thing many of us had to do was remove the carbs (yeah I know this sucks) and bench them so you can clean and ungunk them.
Perseverance will deliver a great reliable ride. ;)
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Offline thrutheframe

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Re: I'm not going to give up on her!
« Reply #13 on: March 09, 2012, 01:49:35 AM »
Thanks for all of the advice! A few things I can add: I've drained the bowls multiple times, they are extremely clean, and the fuel in the tank is fresh, I did try spritzing the intake with starter fluid but it was a no go. Sounds like it's time to borrow a neighbor's timing light. One other thing to note is that if I leave the petcock in the open position, eventually fuel will start coming out of the drain tubes attached to the bowls. Is this contributing to the problem and is this supposed to happen? (floats set too low?)

If your floats are set correctly and your float valves are right, gas will not come out of the overflow tubes if you leave the gas valve on.  Gas from the overflows means your floats are indeed low or just as likely your float vallves are dirty or the rubber tips are hardened and not sealing.
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Offline grcamna2

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Re: I'm not going to give up on her!
« Reply #14 on: March 09, 2012, 03:52:29 AM »
Have you removed you're 4 spark plugs and replaced them w/ the correct Fresh plugs?...even if they "were" New...they may have gotten fouled out from all these starting attempts.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.

Offline KRONUS0100

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Re: I'm not going to give up on her!
« Reply #15 on: March 09, 2012, 06:32:49 AM »
close the choke, roll throttle all way open, and crank 15 to seconds...............................it sounds flooded out to me
if it is.check your floats
MATT
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Offline Really?

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Re: I'm not going to give up on her!
« Reply #16 on: March 09, 2012, 06:45:25 AM »
Hah, just read the first post.  Love those PO stories.  My PO said he rode it all the time to Oklahaoma.  What a load of BS.  It ran when I got there too.  Then it went all downhill.
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Offline Anghil

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Re: I'm not going to give up on her!
« Reply #17 on: March 09, 2012, 10:42:09 AM »
Thanks for all of the advice! A few things I can add: I've drained the bowls multiple times, they are extremely clean, and the fuel in the tank is fresh, I did try spritzing the intake with starter fluid but it was a no go. Sounds like it's time to borrow a neighbor's timing light. One other thing to note is that if I leave the petcock in the open position, eventually fuel will start coming out of the drain tubes attached to the bowls. Is this contributing to the problem and is this supposed to happen? (floats set too low?)

If your floats are set correctly and your float valves are right, gas will not come out of the overflow tubes if you leave the gas valve on.  Gas from the overflows means your floats are indeed low or just as likely your float vallves are dirty or the rubber tips are hardened and not sealing.

You're talking about the little cones that go into the slow jet, right?...there aren't any rubber bits on it, just the metal. That might be why fuel is leaking -.-
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bollingball

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Re: I'm not going to give up on her!
« Reply #18 on: March 09, 2012, 11:51:19 AM »
Thanks for all of the advice! A few things I can add: I've drained the bowls multiple times, they are extremely clean, and the fuel in the tank is fresh, I did try spritzing the intake with starter fluid but it was a no go. Sounds like it's time to borrow a neighbor's timing light. One other thing to note is that if I leave the petcock in the open position, eventually fuel will start coming out of the drain tubes attached to the bowls. Is this contributing to the problem and is this supposed to happen? (floats set too low?)

If your floats are set correctly and your float valves are right, gas will not come out of the overflow tubes if you leave the gas valve on.  Gas from the overflows means your floats are indeed low or just as likely your float vallves are dirty or the rubber tips are hardened and not sealing.

You're talking about the little cones that go into the slow jet, right?...there aren't any rubber bits on it, just the metal. That might be why fuel is leaking -.-

No I think he is talking about the float valve some have rubber tips and some early ones were solid metal. The rubber tip ones seal a little better IMO.
I don't know what cones on the slow jets you are talking about. I will post a photo so you know what I am talking about.

Ken

Offline 70CB750

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Re: I'm not going to give up on her!
« Reply #19 on: March 09, 2012, 02:20:15 PM »
My metal ones looked good and leaked till i replace them. Rebuild kit is excellent start to make the bike reliable again.
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