Setting The Air Gap On Husky 185CD Flywheel/Coil

[Stu in Tokyo]

OK I don't understand how to do this.


This is the flywheel off my Husky 185CD saw, the spark is weak, so I thought I'd check it out, there was some build up shmoo, but not much. I'm wondering if the air gap needs to be reset or checked...?
I got the flywheel off, but how the heck do you check to see if the air gap is correct?
I scribed some marks on the coil and the body of the saw so I could put it back where it started, and when I took the coil off, the holes are elongated in the coil (if that is what it's called) so that the coil could rotate left or right. I'm thinking that elongated holes allow the unit to move eccentrically perhaps to change the air gap?
I understand on other saws how you stick a business card between the flywheel and the coil to check the gap, but on this saw the coil is underneath the flywheel...?

Looking for some instruction.

Thanks in advance.

Cheers from Tokyo!

 

[Stu in Tokyo]

Funny, I thought I would get some input, maybe I'm asking something that cannot be answered?
Cheers

 

[Drptrch]

Funny, I thought I would get some input, maybe I'm asking something that cannot be answered?
Cheers

Ask @Raybenson if there is a shop/service manual, and follow along...


Erik

 

[dswensen]

Measure the OD of the "rotor" and the ID of the flywheel and do the arithmetic?? Don't forget to divide the result by 2 to get the gap.

 

[SEAM]

They probably used a jig...

 

[rupedoggy]

My questions are;
1. How do you know the spark is weak? What voltage does it show. It has been my experience that these ignitions work or they don't. Define weak.
2. Do you know those slotted holes are for ignition timing? There are marks to line up the timing. There is also a mark to check timing with a light at 8,000 rpm.
3. Do you know the gap is set from the factory? If you checked and found it off, how would you correct it?
4. Are you having problems with the saw and guessing it is the ignition? How about giving us a chance to help you and tell us all you know about the problem?

 

[rupedoggy]

One of them, my old Husky 185CD that I like to use on my mill, as it has no chainbreak and it has an old torquey long stroke engine. I recently put a new carb on it and new piston rings, but, I can't get that old saw to run right, but I'm working on it.
This is what I mean. You give more info on this saw in another thread than you do here. Mike

 

[pferdfiler]

There no way to change the air gap on 185-2101 the slots in the module only change the timing

 

[Stu in Tokyo]

Ask @Raybenson if there is a shop/service manual, and follow along...


Erik

Thank you sir!

There no way to change the air gap on 185-2101 the slots in the module only change the timing

Thanks for the information.

 

[Stu in Tokyo]

I apologize Mike, my bad.
I'll do my best to ask you very good questions, I'll answer in-line in BOLD
Trust me that I am not yelling, just trying to answer in a way that is clear.

My questions are;
1. How do you know the spark is weak? What voltage does it show. It has been my experience that these ignitions work or they don't. Define weak.

I do not know that the spark is weak, it does spark, but not very well, in that the sparks I see are small and not very hot looking. I'm comparing the spark that I see from my 3120XP. It is a much newer saw, so maybe that is not a fair comparison?

2. Do you know those slotted holes are for ignition timing? There are marks to line up the timing. There is also a mark to check timing with a light at 8,000 rpm.

I did not know that they are for ignition timing, thank you very much for teaching me that. I certainly makes sense now that I think about it.

3. Do you know the gap is set from the factory? If you checked and found it off, how would you correct it?

I did not know that the gap was unchangeable, that is what I was attempting to ask, in my obviously inept way. Thank you for updating my knowledge on this saw.

4. Are you having problems with the saw and guessing it is the ignition? How about giving us a chance to help you and tell us all you know about the problem?

Yes, I am having problems with the saw, and yes I'm guessing as to what the problem's cause is. More than that it was just one more thing I was trying to eliminate from possible causes.

I will answer the last part of the question in a response to the next post you made.

Cheers

 

[Stu in Tokyo]

One of them, my old Husky 185CD that I like to use on my mill, as it has no chainbreak and it has an old torquey long stroke engine. I recently put a new carb on it and new piston rings, but, I can't get that old saw to run right, but I'm working on it.
This is what I mean. You give more info on this saw in another thread than you do here. Mike

OK I'll do my best to tell you all I know about the saw and try to explain what is happening.

The saw is a 1976 Husqvarna 185CD I bought it used in 2006.

I built a mill for it to slab up a bunch of logs I got locally.

Back then I had problems with it, and I rebuilt the carb, it ran great, and then I put it away for a few years.

Then in 2014 I wanted to give the saw some attention and I was looking into putting a Decomp valve in it, as it is hard starting first thing in the morning, and I've got a bad right shoulder from a crash in my youth that gets aggravated when I have to pull the saw to life too often.

I also ended up replacing some other parts, the drive sprocket and fuel line etc.

Finally here is the thread where I was trying to get the saw to run right back in 2014, I ended up ordering a new carb, and I even found a set of rings for the piston.

By the time the various parts came in I was very busy with life and work and I am only now, almost 4 years later, getting back to work on this saw, I know, pathetic.

Finally here is a short video that I just did showing the spark.



I'm (obviously) not a chainsaw pro.

There is spark, but I know from motorcycle experience sometimes an engine will not start or run well it if has a weak spark.

In conclusion;

The saw has a brand new carb on it.
I set the L screw at 1 turn out from bottomed.
I set the H screw at 2 turns out from bottomed
I put new rings in the saw, it has only been sort of run for a few seconds here and there, the compression show 145 PSI with the new rings.
If I drip a bit of gas into the carb the saw will start and run for maybe 10 seconds.
I do not think that there is an air leak between the carb and the intake side of the engine, both gaskets while not new are in good shape.

If I can answer more questions I would be happy to.
I would really like to get this saw running again, it has done great work milling for me.

Thank you in advance.

Stu

 

[Stu in Tokyo]

I just realized that that Mityvac I have (MV8000) is vacuum only, I will get the MV8500 so I can do a pressure test on this saw to see if the seals or something else is leaking.
I'm going back to Canada on vacation soon, I'll pick it up then, as well as some parts for the 185CD (if I can find them) and the 3120XP as well.
I will get back into fixing this saw at the end of June sometime.
I hope I have not wasted anyone's time, and you will indulge me bringing this thread back to life then.
Cheer from Tokyo Japan.
Stu

 

[rupedoggy]

If I drip a bit of gas into the carb the saw will start and run for maybe 10 seconds.
To me that rules out ignition. If you think a spark is weak then take an old plug and open the gap to about four times normal. If it still sparks then your spark is definitely not weak. Try it.
Now fix the fuel delivery problem. Old dried fuel will sometimes coat the filter or the small screen in the carb. Check the fuel lines carefully for breaks and cracks. Make sure the pulse line is clear (May just be a passage on your saw). That has to be clear all the way to the cylinder. If it is still acting up then a complete rebuild is in order with an ultrasonic clean. If your replacement carb is Chinese then rebuild the old one because those AM are not reliable.

 

[Stu in Tokyo]

If I drip a bit of gas into the carb the saw will start and run for maybe 10 seconds.
To me that rules out ignition. If you think a spark is weak then take an old plug and open the gap to about four times normal. If it still sparks then your spark is definitely not weak. Try it.
Now fix the fuel delivery problem. Old dried fuel will sometimes coat the filter or the small screen in the carb. Check the fuel lines carefully for breaks and cracks. Make sure the pulse line is clear (May just be a passage on your saw). That has to be clear all the way to the cylinder. If it is still acting up then a complete rebuild is in order with an ultrasonic clean. If your replacement carb is Chinese then rebuild the old one because those AM are not reliable.

Thanks for the reply.

OK lets rule out ignition.

The carb is brand new, never used from Tillotson in Ireland, new out of the box, OK it sat in a box in my workshop for 4 years.

You are correct there is no pulse line, but a passage that is part of the carb block on the intake side of the engine, I'll check that.

Thanks again.

Cheers from Tokyo!

 

[Stu in Tokyo]

Oh, one more thing.


The wire that goes from the armature to the on/off switch has seen better days.
Suggestions on fixing this?
It still has continuity, but I thought at the very least I should take the end off that attaches to the switch and maybe put a piece of heat shrink tubing over it then reattach a new connector on it, opinions?
Cheers

 

[SEAM]

Shrink tube from the local home center will definitely improve the wire...
Those cracks may weaken the spark as current can seep through the insulation and leak to ground - the switch cuts the engine by grounding (removing the spark) .

Re-check the spark after fixing the wire.

 

[Stu in Tokyo]

Shrink tube from the local home center will definitely improve the wire...
Those cracks may weaken the spark as current can seep through the insulation and leak to ground - the switch cuts the engine by grounding (removing the spark) .

Re-check the spark after fixing the wire.

Thanks for the reply, I was worried about the wire grounding out, I'm sorry the picture is a bit out of focus, but it does not look like it was grounding out, no burnt areas. I can get the waterproof kind of Heat Shrink Tube, maybe that is a little more durable?
I'll add this to the list of things to fix.
Cheers from Tokyo!

 

[Okie]

You say it will run for 10 sec with a prime. If so it's probably not ignition, it's fuel supply related.

Some of the Husky's used a primer bulb.

Does yours have a primer bulb?

If so check and make sure ithe primer bulb is plumbed correctly. It should SUCK fuel through the carb (line going to the carb is suction from the primer bulb) the other primer bulb line is a fuel return going to the gas tank. (output from the primer bulb)
Very easy to get them plumbed wrong, especially during a complete engine overhaul and replacing the lines, etc.
Engine will have the symptoms you describe except it will not cause spark issues.

Several good you tube tips on how to test the connections, etc.

 

[rupedoggy]

Okie, turn in your guru badge. The 185 NEVER had a primer bulb.

 

[Drptrch]

Okie, turn in your guru badge. The 185 NEVER had a primer bulb.

That’s funny


Erik