Re: 502 Refurbishment
Posted: Tue Jan 19, 2016 11:11 pm
The Hirth recoils are nothing to be scared of. They are far more simple than the JLO recoil.
To pull apart:
- If your recoil has the three angled tabs, you will need to slightly punch the roll pins in to get the tabs off.
- Remove the starter cage with the rollers.
- Turn the spring housing and you will feel it rotate off those three pins.
- Carefully remove it with the spring.
- Pull most of the cable out, then pull the cable reel out.
Don't worry about the spring getting out of the housing. Just hold on to it, remove it and let it unwind.
So now you have it all apart. If you punched the roll pins in, punch them back out so they are centered in the rim (sticking out on each side of the hole). Clean your parts. Lets start with the cable and cable reel. If you have an original metric cable, it is about 0.113" in diameter (not sure what millimeter it is) and is about 88" long. If your cable is shorter than 88" long, then someone probably cut it off because it wore at the starter handle. If the cable is significantly shorter (more than 8 inches), you may have a problem.
The thing to know about these recoils is the dead end of the cable on the cable reel is not secured to the cable in a firm fashion. If your cable is short and you make long pulls on the recoil, you can easily pull the cable right out of the recoil. So if your cable is short to start with, that hurts your cause.
Another challenge is if someone put in a standard cable that they got here in Northern America, chances are it is a domestic cable which is not as bendable as an original cable and is larger in diameter by more than 0.010" That does not sound like much, but the most domestic cable you can get on the cable reel is about 77", so already, you lost 11" of pull length. I have the correct Hirth cables if needed.
One technique I use to keep the cable in place on the reel is to put the cable under the tab, and then punch the tab down on to the cable with a thin chisel. This clamps the cable end and you are less likely to pull it out if you get to the end of the stroke. If you have an original size cable and can get the full 88" on the reel, then you can make a pretty significant pull on the cable and still have some cable left on the reel which is the best of both.
Pull the plastic grommet out of the recoil so you can route the cable through the outlet throat. Have 1/2 the cable out of the reel and install the reel in the housing. Wrap the cable on to the reel.
Clean your recoil spring. Then put a light coat of thin oil or lubricant on it.
Put the spring back in the spring housing by putting the circular end on the post and wrapping it clockwise, walk the spring in to the housing. Before installing the assembly, it helps if you bend the tab that the spring's live end will grab out slightly so you can get the spring "hook" to grab the tab. Insert the spring housing into the assembly. Pull the cable outward and you should see the hook of the spring against the tab. Using a screwdriver, put the hook into the tab. Fully insert the spring housing. Now you can turn the spring housing in 1/3 turns and you will see that every 1/3 turn, it will grab those roll pins and tighten the spring. I usually tighten the spring by rotating the housing a turn to a turn and a third or so. Don't overdue the tightening because if it is too tight, when you pull the cable, the spring could run out of travel. You can pull the cable out and let the recoil pull it back in at this time to see how it is working.
Next is the starter cage. The important thing about the starter cage is not to get it full of grease and do not lubricate the spring washers under the snap ring. The rollers do not need much lubricant to keep them free and the spring washers are a brake for the cage.
So install the starter cage with the spring on and install one roller by pulling the spring outward with a pic and setting the roller into place. Pull the cable and the roller should pop out. If it does not, pull the starter cage off and turn it 1/2 turn and reinstall it. It has a left hand and right hand position and when it's correct, the rollers will pop out when pulling the cable.
There are typically two spring washers under the snap ring. Usually one does not provide enough friction to get the rollers to pop out properly. If the rollers do not fully pop out when pulling the cable, it will occasionally not catch when you are trying to start the motor and everyone knows how frustrating that can be. If you grease this cage up, you will have the same issue with the rollers not popping out their full distance.
Put the clips back on if you had them. Reinstall the recoil on the motor and route the cable through the dash.
That is it, you have a good recoil. About 1/2 to 1 hour.
To pull apart:
- If your recoil has the three angled tabs, you will need to slightly punch the roll pins in to get the tabs off.
- Remove the starter cage with the rollers.
- Turn the spring housing and you will feel it rotate off those three pins.
- Carefully remove it with the spring.
- Pull most of the cable out, then pull the cable reel out.
Don't worry about the spring getting out of the housing. Just hold on to it, remove it and let it unwind.
So now you have it all apart. If you punched the roll pins in, punch them back out so they are centered in the rim (sticking out on each side of the hole). Clean your parts. Lets start with the cable and cable reel. If you have an original metric cable, it is about 0.113" in diameter (not sure what millimeter it is) and is about 88" long. If your cable is shorter than 88" long, then someone probably cut it off because it wore at the starter handle. If the cable is significantly shorter (more than 8 inches), you may have a problem.
The thing to know about these recoils is the dead end of the cable on the cable reel is not secured to the cable in a firm fashion. If your cable is short and you make long pulls on the recoil, you can easily pull the cable right out of the recoil. So if your cable is short to start with, that hurts your cause.
Another challenge is if someone put in a standard cable that they got here in Northern America, chances are it is a domestic cable which is not as bendable as an original cable and is larger in diameter by more than 0.010" That does not sound like much, but the most domestic cable you can get on the cable reel is about 77", so already, you lost 11" of pull length. I have the correct Hirth cables if needed.
One technique I use to keep the cable in place on the reel is to put the cable under the tab, and then punch the tab down on to the cable with a thin chisel. This clamps the cable end and you are less likely to pull it out if you get to the end of the stroke. If you have an original size cable and can get the full 88" on the reel, then you can make a pretty significant pull on the cable and still have some cable left on the reel which is the best of both.
Pull the plastic grommet out of the recoil so you can route the cable through the outlet throat. Have 1/2 the cable out of the reel and install the reel in the housing. Wrap the cable on to the reel.
Clean your recoil spring. Then put a light coat of thin oil or lubricant on it.
Put the spring back in the spring housing by putting the circular end on the post and wrapping it clockwise, walk the spring in to the housing. Before installing the assembly, it helps if you bend the tab that the spring's live end will grab out slightly so you can get the spring "hook" to grab the tab. Insert the spring housing into the assembly. Pull the cable outward and you should see the hook of the spring against the tab. Using a screwdriver, put the hook into the tab. Fully insert the spring housing. Now you can turn the spring housing in 1/3 turns and you will see that every 1/3 turn, it will grab those roll pins and tighten the spring. I usually tighten the spring by rotating the housing a turn to a turn and a third or so. Don't overdue the tightening because if it is too tight, when you pull the cable, the spring could run out of travel. You can pull the cable out and let the recoil pull it back in at this time to see how it is working.
Next is the starter cage. The important thing about the starter cage is not to get it full of grease and do not lubricate the spring washers under the snap ring. The rollers do not need much lubricant to keep them free and the spring washers are a brake for the cage.
So install the starter cage with the spring on and install one roller by pulling the spring outward with a pic and setting the roller into place. Pull the cable and the roller should pop out. If it does not, pull the starter cage off and turn it 1/2 turn and reinstall it. It has a left hand and right hand position and when it's correct, the rollers will pop out when pulling the cable.
There are typically two spring washers under the snap ring. Usually one does not provide enough friction to get the rollers to pop out properly. If the rollers do not fully pop out when pulling the cable, it will occasionally not catch when you are trying to start the motor and everyone knows how frustrating that can be. If you grease this cage up, you will have the same issue with the rollers not popping out their full distance.
Put the clips back on if you had them. Reinstall the recoil on the motor and route the cable through the dash.
That is it, you have a good recoil. About 1/2 to 1 hour.