Auto Clutch no.1 Springs

Bike 81 420 Auto.
I am trying to replace broken springs on clutch no.1, The manual just glibly says use a spring hook to fit spring. I am unable to even get the spring through it's centre hole, let alone stretch it over the brass weights! The only way I think it can be done is to remove the 32mm nut, pull the centre rotor of, disassemble the brass weights, fit springs , reassemble centre rotor and fit back on to crankshaft. Is this the correct way? If so where did the stories of replacing springs on the side of the trail come from?
I have searched previous threads an could find no specific advice.
All help and advice gratefully received

I have posted previously pertaining to the 430 auto that when pressed about changing the spring trailside in fact they only removed the broken pieces. Like you I only have installed the springs with the center and bob weights removed as a unit from the crank end. It may be possible with enough force but I can't see doing it without permenantly deforming the spring. The manual you have does say to retorque that center nut a few times in the first couple of hours doesn't it? Even if it is possible they are now vintage bikes and no one is running in an event with championship points so I would tend more toward pulling the bike out and washing it off unless it was real far and /or hilly. At leasst if it is like mine covered in mud or similar earth materials.

Fran

Thanks Frank for confirming what I thought, my bike does tend to be covered in mud!

I am just adapting my 3 leg puller with some 6mm threaded legs to go into the 6mm threaded holes in the rotor centre, do you apply a bit of heat to the rotor? The centre which donated the springs is split in half through the key way! and I don't want to break mine. Also making a locking bar for the clutch, though the nut came of with the impact driver, I guess you use the holes in 2 of the brass weights?

Yes, that's what the workshop manual shows, using the holes in 2 of the shoes ("brass weights"). It says to torque the nut to 90nm.

That tapered keyed connection to the drive hub can get fused or kind of like welded on. I have a 420 crank the guy repaired in an aircraft shop but the repair failed, a 430 which ruined itself totally on my watch and a 500 one (got that as a parts engine) which was extremely hard to get off using all the puller had and air/acetylene. Maybe even oxy acetylene in a small flame I really don't recall but it was a real battle. At some point you have to start with a hammer for shock on the center bolt of your puller. I am not aware of hydraulic stuff small enough fit to use instead of the screw type puller. I made a holding device for two holes, just a flat bar tapped holes then run bolts with heads removed and not fully threaded until the threads are fully in.

http://www.frannyk.addr.com/cafehusky/worn.in.jpg

This picture wasn't really to show the crank end but I stuck it in the background. Hope you don't have this issue.

Fran

I found it easy to fit springs to my 420,the spring ends would just pop in both ends at the same time,BUT be aware that the 430 and 420 springs are different.I very really broke the springs till I replaced them,then I broke lots.Till I discovered I was being supplied with the supposedly improved later 430 springs,checked the part numbers and the story was told,use the right springs and none broke anymore

My centre came of okay with just a little use of the battery impact driver. It was then reasonably easy to replace the springs. The donor engine has no number but I think it is a 79 390, the springs seemed identical to the one I had left! I will try starting her later today and we shall see. I am sure I read some where about fitting a cover to the clutch to keep the bits in, seems like a good idea to me looking at the mess inside the cover.

I would suggest replacing the key every time. That may well have something to do with the failure I describe. It is probably a standard metric size but the hardware stores around here don't stock metric keys. It is kind strange how when I buy ford parts at the ford dealer's parts counter they give me little extra pieces or sell me them and say you should put in a new one of these if you do that, same at the location for other items with parts in need of replacement but at the bike shop years later I figure it out.

Fran

Something must be wrong with the springs, I thought they went on a bit to easily , no matter how slow the tick over, and I have got it slow ,slower than before my "repair" she just stalls, even rolling down the drive and click in to gear did not help. Now where to find some springs

Tritrophy has some new old stock springs for an 87 bike
1987 Husqvarna 430 AUTO 3 SPRING SET PRIMARY CLUTCH NOS

are these the same?

I'd guess, no. Those 1987 springs are part number 16 17 027-01 which are for the first gear clutch on the 430 3-speed automatic. The 420 4-speed automatic's first gear uses spring part number 16 12 556-01 (41 kp weight) which were later replaced with part number 16 12 793-01. These usually have no paint color or sometimes white paint. You need spring with the proper physical dimension and tension.

I know you asked where to get some.

Why don't those work though I didn't look up the 390 but the 360 and the 420 both use the same spring # which has been superceded by the 500 version.

Quick Order Confirmation

Part number 161255601 has been replaced by 161279301.
Part number 161279301 was added to your cart. - $8.95

161279301 NLA---CLUTCH SPRNG--1ST 500AE Invalid QTY $8.95

I am not sure I know how to tell a 360 from a 390 they both have helical cut primary drive gears. It also kind of looks like the 430 ones could use the earlier springs as well because they have an unused hole.
The only 420 I have is assembled and the other guys might be a bit more accurate with this issue because the springs never gave me an issue it was that one way thing to get it started or corrosion on the crank.
http://www.frannyk.addr.com/cafehusky/3.auto.hubs.jpg

Oh those 430 springs are there so you can try and tell if there is a color difference.

Fran


from left to right, 3?0, 500, 430

Fran, what vendor has the 161279301 springs for sale?

I don't have an answer to that. None that is plugged into the husqvarnaoutlet part finder system. Though I only put in the earlier number over there.

In this case he might get exactly what he has just unused. Zim perhaps has stated that superceded part doesn't work well.

There is a guy on here but not in this section who made a set of powervalve springs for the modern 125. I don't know if he had springs made or knows how to look for springs in the industrial world. I am pretty sure his name is wallybean or somethig like that. I kind of think that is the way to go there are only going to be so many new old stock and sometimes a lot of that kind of stuff is seconds (rejected by the quality control department). If you believe this article linked lately all those springs and one way clutches must be over the counter items .....right?....http://www.motorcycle-usa.com/290/1445/Motorcycle-Article/MMC-Husqvarna-Army-Automatic.aspx

One might also note the latest post in the automatic on ice thread that says the Swedish army is still using a 250 automatic at least once a year so that might also be a way to look if you didn't start hoarding parts years ago.
Fran

There is a cover for the springs I don't know the part # but I have a picture of one some where on my computer, they used them on the Military Autos. It looks like one could be easily made buy a good fabricator.

I think I will try to make up one of those plates. The inside of my side cover is all gouged up when a spring broke before. I wonder if the rattling noises I hear at idle will get better with that plate against the springs?

I would love to get a new set of springs for my 420AE. It doesn't seem like rocket science. Maybe we could have some made.

Maybe with better quality metalurgy as well,I dont know about the 2 differant part numbers for the 420,alls I know is the 430 spring lasts about 2 hours if your lucky using it in a 420.Eyeballing them from memory,the 430 spring is maybe 2 or 3 mm shorter.My parts supplyer at the time was Husky Imports,they were the distributors of Huskys in OZ from 1985 to maybe 6 years ago and when I was looking at why they were braking was they were supplying THE NEW best avalable spring,when I checked the part numbers and found they were supplying 430 springs,when back to the 420 part number and havnt broken one since,they sold all there old bits to Husky Parts Australia.So I dont if I ended up with either of the 420 springs but 1 or the 2 is the go.

If you look at the picture I posted, the 430 springs are the ones which are loose and I call pig tail ones. The others have a real hook on each end. If you look at the one with the packing peanuts (ebay deal) you see the pig tail springs use a hole in a different location on the center hub. Kind of like Zim says but not exactly. With the 430 when parts were available and one drove to the dealer I purchaced the 430 clutch kit but used springs purchaced seperately as they had a different color hue. The kit was approx $150 and included drum, and shoes, and springs, and some little fastners. It did not incluce the pivot pins or the starter pieces. The 420 set up with bronze shoes with slots on a slight angle I believe is superior to the later design with the little starter pieces and the slots cut into the drum.

Fran

My friends have already looked at getting some made but most of the springmakers will not do small runs.
I don't think you want the cover to put a lot of pressure on the spring as you can see it has a little bit of curve to give the spring some clearance.