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Discussion Starter · #1 ·
Hey, Nebie here, just got my first HD (Basket case) I rebuilt it from the ground up, she's a 77 Sporty. I got it all together, went to start her and nothing. She turns over but won't fire up. before when I first tried all she would do is crank and then back fire. I checked the cams to make sure they were linde up and noticed the front intake was wrong, fixed that and the back fire stoped but she still won't run. The ignition time is right (or atleast real close) Spec says .018. What could be the problem. Any help would be greatly appricated. Thanks

Daryl
 

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check to make sure your push rods are adjusted right. no up or down but they should still spin freely. to get cams in the lowest position. take spark plugs out, lift the lower portion of the push rod tubes,i use to use a piece of wire clothes hanger bend on each end,hook on the bottom end of push rod tube and hook other end over the middle part of the rocker box.i've seen people use wooden clothes pins the kind with the springs in them clamped to the push rod holding the lower push rod tube up.get the rear wheel off the ground,put the trans in high gear,turn the wheel by hand until the cams come around to their lowest point. check push rods there.
 

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Discussion Starter · #3 ·
when I check the push rods, your saying I want the Tappets down at their lowest point, then I would lift the push rod and addjust the tappet so there is no up and down play in the push rod? Just out of couriosity, Would that also make it have low compression? (not sure how much I should have anyway) Thanks I will check the rods tomorrow, Also would this have anything to do with the pistons or rings? I put new pistons and rings, had the heads redone, honed out the cylinders. The whole topend is like brand new. Sorry to ask somany questions, Iam trying to learn as much as I can.. Thanks for your help.
Daryl
 

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Ironhead1977 said:
Spec says .018. What could be the problem. Any help would be greatly appricated. Thanks

Daryl
That would be the points gap the timing is adjusted by moving the plate the points are mounted on and using a timing light on the flywheel through the plug in the case on the other side of the bike.
Get yourself a service manual and read it :cool:
 

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Y2K said:
That would be the points gap the timing is adjusted by moving the plate the points are mounted on and using a timing light on the flywheel through the plug in the case on the other side of the bike.
Get yourself a service manual and read it :cool:
Exactly! Get a FACTORY service manual before you do anything else. Clymer, Haynes, etc. manuals suck. Very inaccurate and missing a lot of data.

Those old Sportys are very simple engines to troubleshoot. Not much more difficult than a Briggs & Stratton lawn mower engine.

Lets start with the basics.....

Did you check ALL of your ignition-related wiring?
Battery fully charged?
No corrosion on ANY terminals?
New coil, plugs, plug wires?
New points assembly?
When checking the .018 points gap, make sure it's the same on both lobes of the points cam.
Is your advance mechanism in good shape? The flyweights tend to wear out (the pivot holes) after a while.
What about the condensor?
Did you static time the engine as per the manual, using the TDC mark?
You said the cams are indexed correctly now... good.
Did you perform a compression check? Get a gauge at Sears and do it. Pressure should be within 10% between the cylinders.

Now for the fuel system.

Is the carb new or recently rebuilt?
Is gas getting to the carb?
What kind of carb are you using? Does the accel pump squirt (if it has one)?
Does it have a choke or enricher? Is it working?
Filter clean?
Good gas in the bike?
Try a small squirt of starting fluid (be careful!) and see if it starts to fire.

Pushrods? Check as ironhead mentioned. Use the manual to do it correctly! Do it wrong and you could bend a valve.

You were asking about the rings... a compression test will verify if it's good or now. Expect at least 100 psi. It will vary a bit, depending on your pistons and cams.

Let us know how it goes. Good luck! :)
 

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Discussion Starter · #6 ·
Y2K said:
That would be the points gap the timing is adjusted by moving the plate the points are mounted on and using a timing light on the flywheel through the plug in the case on the other side of the bike.
Get yourself a service manual and read it :cool:
Ok you got me on the points gap, my bad. But don't you have to have the motor RUNNING to check the timing?:confused: I have two manuals one is the HD manual and the other is the Haynes. As far as troubleshooting goes they aren't very helpful. once I find the problem Then the manual comes in handy. It's finding the problem I am having trouble with. I appreciate all your guys help. I will check everything you have said to look into. Thanks again.

Daryl
 

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Ironhead1977 said:
Ok you got me on the points gap, my bad. But don't you have to have the motor RUNNING to check the timing?:confused: I have two manuals one is the HD manual and the other is the Haynes. As far as troubleshooting goes they aren't very helpful. once I find the problem Then the manual comes in handy. It's finding the problem I am having trouble with. I appreciate all your guys help. I will check everything you have said to look into. Thanks again.

Daryl
The books should tell you how to static time the engine to get it to start. Once it's running, then you would use a timing light as per the HD manual.

If you have it static timed correctly and it still won't start, then it's time to look at some other things. Just go through the list I posted and you'll eventually find it. By the way, what carb do you have and what has been done with it? Ya gotta make sure it's getting fuel. An intake leak will also cause a lot of problems. This engines have a crappy intake seal design. I usually loosen the cylinder base nuts to help align the intake manifold, then tighten the nuts after the intake clamps are torques. Your front cylinder is critical. That engine will run on just the front cylinder, but not just the rear. I've ridden several miles on just the front jug. If that one dies, it won't start at all.
 

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ToddM said:
Is your advance mechanism in good shape? The flyweights tend to wear out (the pivot holes) after a while.
What about the condensor?
Did you static time the engine as per the manual, using the TDC mark?
Here's the answer to if the motor has to be running to time the iginition.
"Did you static time the engine as per the manual"

This is done with engine off , the flywheel in the correct position and then turning the points plate.
It will get it close enough to run pretty good and then you can time it with a light.
Read up on static timing and check that advance unit! :)
 

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Discussion Starter · #9 ·
No I have not static timed the motor, I belive the carb is a kline, I have done nothing to to the carb, The guy who had it before me said it was new a few years ago. I will work on the bike and do what you all have told me to do, and let you know how it turned out, Again guys thanks for the help...
 

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Takes less than a few years to mess up a carb if it was left sitting long enough with gas in it. I would most certainly look at that.
 

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Discussion Starter · #11 ·
Got it running, (for a minute) She had a fast idle, which that didn't surprise me, but when she reved up 3000rpms by herself Then I got worried, so I hit the kill switch and shut her down. Checked the idle screw and that was fine, I think somehow the throttle cable might have something to do with it? everything looks fine, So after I nearley pissed myself, We tried to fire her up again, and she wasn't hitting off the front cylinder, I checked the push rods and the front intake was really loose, (I had adjusted them all yesterday) I thought that was strange. No compression on the front cylinder, I thought the intake valve might have got stuck, yep it did! I took the heads apart and got it to close, compressed it and made sure it would open and close, Put it all back together today, tried to start her again, wouldn't start, After about an hour she fired up, and started to rev around 3000rpms, shut her down and low and behold the front intake valve was stuck open again. What can cause this? And how do I fix it,Sorry this one is so long, Also can some tell me how to Static time, I cant find it in the HD manual, Thanks....
Daryl
 

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Ironhead1977 said:
I just had the heads done, Valves, guides, springs everything. Back to the garage to tear it all down AGAIN..... Thanks,,
Daryl
What cams do you have in it? If they aren't bolt-in, did you check the piston to valve clearance? It's also possible that you bent the valve since one of your cam gears was indexed wrong earlier. Do you see any marks on the piston or valve that could indicate that they made contact? It only takes an impact of a couple thousandths of an inch to bend the valve stem. Did you use plenty of assembly lube when putting it together? I load up the valve stems with it since it the engine will turn over several times before enough oil reaches the top end to lube the valves. Did you check the tolerence between the valve and guide? I don't have the book with me now, but you can look it up.

Not sure about the high idle. Check your cable for free movement and make sure it's letting the carb go all the way back to the idle stop. Is this a new carb? What kind is it? I'm more familiar with S&S Super, since that's the only carb I've used for years... one of the best performing and easiest to tune carbs available, IMHO. ;) How did you set the carb adjustments for initial starting?

Have you checked for intake leaks? Those engines have a lot of problems in that area.

To static time:

First, adjust your pushrods again... pushrod at it's lowest point, spins freely with no up or down movement. Make sure that the lock nut on the adjustment is tight. They have a tendency to loosen up and the pushrod will go out of adjustment. I usually check them at least once a month.

Then slide up the cover on the front exhaust pushrod. Hold it up with a rubber band and paperclip, or a clothes pin.

Now rotate the motor until the front exhaust pushrod is closing (pushrod moving down). To make this easier, lift the rear wheel and put it in 4th gear. Then turn the wheel to rotate the engine. Keep the spark plugs out when doing this.

Now, looking through the timing hole on the left side, watch for the timing mark as you keep rotating the motor. Center the mark in the hole. Your front piston should be near the top of it's travel. You can put your finger over the hole to tell if it's coming up.

Now go the the points plate. Rotate the plate fully counter clockwise.
Then rotate the points "cam" that the points rub on against the advance spring pressure. Holding it there, rotate the timing plate just until the points start to open. I think you use the wide lobe. Tighten down the cam plate holddown screws (posts).

Rotate the engine and verify that the points open the same amount on each lobe (.018).

Now you have it static timed. You should be able to start the bike now and then set the timing with a timing light.

Hint: If you need to find new points and/or condenser when you are on the road, you can go to an auto parts store and get a set from a 6 cylinder 250 ci Chevy from the 60s or 70s. I've had to do this twice in the past. I found that they actually seem to last longer than the HD points. :)

Hint #2: Get the Harley "What fits what" book for future reference. There's a lot of stuff in there that can save you a fortune. You can usually find the book for under 12 bucks.

Hint #3: When setting dynamic timing (engine running), you can use one of those clear timing plugs to keep the oil off of you, or you can use a piece of window screen between the light and the hole. That will keep most of the oil away from the light and will make the mark easier to see. If you don't mind getting a little dirty, you don't have to use either. Just make sure you are wearing safety glasses to keep it out of your eyes. You can also use white paint or grease pencil in the timing mark to make it more visible, like you would on a car engine.

By the way... where in NY are you? Are you upstate (north of Albany)?
 

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Discussion Starter · #15 ·
ToddM, And all who have helped me so far,,,,,,,
WOW:bowdwn: Thanks for all the help, I live in the Southerntier of NY, 1/2 hour west of Binghamton off 17/86, In Horseheads, NY. I took the head back to the guy who did them and had him look it over, We pulled the valve and it was scored on both sides, there was a small bur in the guide, with a little persuasion :265: I got him to redo the intake valve. She's fine now. The carb is a Kehine (sp) an origanal HD carb. At least it says HarleyDavidson on it.. I Turned the slow fuel screw till it seatted, then opened it 7/8 of a turn, Still have some adjusting to do. We got her running twice today, both times she ran normal (little out of time) She would run for a second and start to idle a little fast, maybe 1200rpms, Then if you twist the throtle quick, bang, 3000rpms at least. The throtle cable is fine, the idle screw is not even touching the throtle lever, I think the float is stuck, and the gas is building up in the bowl and when you twist the throtle all that gas pours in th the carb, Two other people comfirm my theory. So I think I will rebuild the carb tonight. I will static time this weekend, could that be why it"s so hard to start? There is no choke in her, The guy who had it before me must have removed it. ( can't figure why?) So I think if I get the carb done and static time the engine I should be good to go. Oh yeah and recheck the pushrods. I will post some pics of her later.
 

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Ironhead1977 said:
Here she is, all done.
And this is what she was three weeks into the build
Thanks for the help guys......
Daryl
Looks good! So I guess the carb rebuild fixed it? I didn't even think about the float level, but the next recommendation would have been a rebuild, especially since it's an original carb. Cheap and easy to do. I rebuild mine every couple years just for piece of mind. Good to hear it's running! :D
 

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Discussion Starter · #18 ·
Still need to do the carb, Not sure if that is something I want to do, Was pricing new carb, (man not cheap) I guess a Rebuild would be my best bet, trying to save some money, So it is pretty easy to do?
 

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Ironhead1977 said:
Still need to do the carb, Not sure if that is something I want to do, Was pricing new carb, (man not cheap) I guess a Rebuild would be my best bet, trying to save some money, So it is pretty easy to do?
Sorry, but from your last post, you said you "got it done". That sounded to me like you got it running. :duh?:

Carb rebuilds are a piece of cake if you follow the instructions. Clean and inspect all the parts and don't lose the little pieces. I like to take them apart in a large plastic container, like a litter box. That way there's less chance of something getting away from you.

If you decide on a new carb, I'd have to recommend the S&S Super E. I've built many, many bikes and that's the only carb I'll use. It costs slightly more than some of the CVs, but it very simple in design, easy to tune, and very reliable. Set it once and forget it. :) You can get them cheaper on ebay. They will perform well on just about any engine you can build, no matter how powerful. 99% of all drag bikes run them for a reason! Anyway, that's my 2 cents. :yes:
 

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Discussion Starter · #20 ·
Sometimes my wording is messed up.. sorry about that. I was looking into the S&S carbs, not to cheap.... But like you and most of the people I have talk to All say pretty much the same thing, I think I might just rebuild this one for now and this fall go with the S&S Super-E,, That seems to be the faviorte of everyone. Now what about the Super-G, or is that For the bigger Bikes? Thanks for the Help.
Daryl;
 
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