73 sportster help me please

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73 sportster help me please

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73 sportster help me please - 5/7/2008 1:26:45 PM

k68jeep

Posts: 3
Joined: 5/5/2008
Status: offline

resently bot back a 73 sporster,i used to own,when i sold it the only thing wrong with it was the transmission,when i got it back the guy had taking out the motor and took the top end apart,and the cams and oil pump out,i got it back in peaces,i have very little exsperance working on harleys,i put it back to geather by the book,it trys to run,when u kick it it will sputter and try to run for a few sec,then it spits gas out the carb,and the kick starter comes back up hard,i mean real hard,i have replaced the coil,points,plugs,condenser and wires,
anyone got ant ideas,thanks.

Post #: 1

RE: 73 sportster help me please - 5/7/2008 1:59:57 PM

piniongear

Posts: 1621
Joined: 2/13/2006
Status: offline

Whew!
Since you have had the engine apart, and claim to know little about Harleys, but you have put it back together anyway...... I am almost afraid to venture into these waters.
All we can do is assume that you have the cam end play correct, have the cam timing correct, the pushrods adjusted correctly, etc., etc.
The reason this bothers me is because taking out the oil pump is a serious thing to do. It's not taking it out, it's putting it back in correctly and getting the oil pump breather. the engine position correct and all of the cams gears lined up. This is quite a job if you are not familar with how to get it back together correctly.

From the sound of things, the spark timing may be advanced. This will (or can) cause the kick back. Having said that, not having the cams in proper time with the crank shaft or each other is something that will make it kick back also. If this as the problem, you do not want to run the engine or you will have serious damage.

Does it start up easy and quick, even though it does not run long?

Do you know how to time the ignition on the engine? Do you have a timing light?
That would be a good place to begin if you feel sure you reassembled the engine correctly.....pg

_____________________________

Rolling down the highway on two wheels since 1957...
Owner Red/White 1971 XLCH & 2003 FXDL-Silver over Black
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(in reply to k68jeep)

Post #: 2

RE: 73 sportster help me please - 5/7/2008 2:29:27 PM

k68jeep

Posts: 3
Joined: 5/5/2008
Status: offline

in my own defence i was not the one who took it apart,it ran great when i sold it,when i seen when was done to it i got sick to my stomic,i am a strong beleaver in,if it ant broke dont fix it,
i do beleave i got all the timing marks back ware they should be,including the oil breather marks,
the funny thing about it was i got rid of it because of the transmission,and i was able to fix it,the only thing that is not perfect when it comes to the timimg marks is the oil breather, hole will not line up dead center of the notch cut in the pump housing it sits about half a hole off.

as i under stand it when the slash mark on the left side is in the middle of the hole,the breather mark
should be set there,then you rotate the crank to get the cam mark lined up,and allso i got the spacers for the cams in play in place as they should be

(in reply to piniongear)

Post #: 3

RE: 73 sportster help me please - 5/7/2008 3:20:07 PM

piniongear

Posts: 1621
Joined: 2/13/2006
Status: offline

I feel relived!
Yes, it sounds like you did it correctly.
Slash mark directly centered in the hole.
Oil pump drive gear engaged with the oil pump sleeve gear.
The hole in the oil pump breather sleeve lines up with the notch.
Now you no longer have to be concerned where the timing mark or the hole in the sleeve are located.
You timed the cam gear marks and piniongear together.
You kept the correct shim packs with the respective cams.
Cam plates were installed with the bevel on the holes facing out, toward the cam(s), right?

OK, then the next thing to check is the ignition timing. Before doing that, set the point gap(s)

Measure the gap at both igniton cams. The ideal gap is .018. The maximum gap difference between the two lobes is .004.

As an example: Lets say you set the first lobe with the gap at .018. Rotate the engine forward and check the gap at the other lobe. Lets just say the result is .014 at that lobe. OK, .004 difference is within specs, but you can improve on that.
Go back to the first lobe and reset it to .020. Check the other which should have a gap of .016 now. You see how you are evenly balanced on each side of that recommended gap of .018? If the difference in the two gaps is greater than .004 then buy a new ignition cam and install it.
Now go on to checking/setting the ignition............pg

_____________________________

Rolling down the highway on two wheels since 1957...
Owner Red/White 1971 XLCH & 2003 FXDL-Silver over Black
http://area51.tzo.com/bperry/gallery

(in reply to k68jeep)

Post #: 4