McCulloch Mini and Small CC Chainsaw's

[joeymt33]

You probably have done most of these but it doesn't hurt to double check

Is the choke lever stripped? Does the choke valve open close?

Can you test compression?

Can you post a pic of the Scoring you noticed?

Have you replaced the spark plug?

Have you verified that the plug gap is .025" exactly? These saws don't like a large plug gap.

Is the muffler or exhaust port plugged?

Check the coil real good. It has insulating washers and in some cases sleeves for the 3 carb mounting screws.

Check under the points cover and make sure it's clean

Check, adjust, clean point gap

Make sure there's not any skint places on the plug wire or ground wire on the coil.

Set the lamination gap around .011"

Check the condenser wire for chafing.

 

[sawdummy]

Ok guys, I'm here in the lehigh valley of PA. I can no longer get in touch with the guy that I got the saw from and I was hoping to figure this out myself and learn something along the way. I'm going to have to post some pictures later but I've done almost all of above but I'm not too familiar with the points gap and lamination gap. I have a gauge for pressure testing but no way of creating pressure. This is new to me and I thank you guys for coaching me through this. What kind of tools do I need to check these gaps. Also I read somewhere that if you can hold the pull cord and the saw falls all the way down then you don't have good compression. Is this true?

 

[joeymt33]

I use a compression gauge from sears.

And feeler gauge also from sears.

 

[dads_old_mac]

Hey guys. Looking for someone with a 110/mini Mac parts saws. I love these things. I can't find enough of them. Recently I came across a bin full on the local classifieds. Most are complete, but I need some help for parts on the few left.

If anyone has parts saws lemme know. I could use some of the little stuff.

Thanks!!
-Scott

 

[heimannm]

Not sure if this is a legitimate request, or just some joker pulling my leg but I'll risk it.

Try eBay, you can find almost everything there.

I have some parts, PM with part numbers and/or descriptions and I may be able to help.

Also try Bob Johnson (607 638 9297) or Fayetteville Equipment.

There are tons of MM parts and saws available.

Mark

 

[dads_old_mac]

Unfortunately I'm not a joker. Just enthusiastic.
I'll send you a PM.

 

[workshop]

I have to admit to a certain satisfaction with them and I actually enjoy working on them. They fit perfectly on my little tv table so I can work on one while inside watching the telly.

 

[dads_old_mac]

I still have almost one saw left to put together. And 2 in parts

 

[workshop]

Nice looking group of minis you've got there.

 

[Wood Doctor]

Hi Guys. A lady begged me to fix her son's Mac 3818. I replaced all the fuel lines and the bar oiler line. I also made a new choke control in my shop to replace the broken one. I also fixed a broken handle spring. The saw's engine now runs like a champ BUT--the bar oiler is not sending any oil to the slot, not a drop.

I checked the oil hose's pickup body and it's clean. Bar oil is making it completely through the hose and out the oil tank, but it never makes it to the bar slot or oil port on the other side. So, it seems to me that the pump is at least getting something done right. I've tried squirting carb cleaner and/or mixed fuel down the tiny oil exit port hole, but that also has failed to unblock anything.

I tried getting to the pump to replace it, but for the life of me I cannot take it apart and get to it after removing the clutch and sprocket and a bunch of screws. Please advise. Before doing that again, is there anything else I can do (such as compressed air) to remove the obstruction, assuming that's the problem? At this point, I hate to part out a Mac with a running engine, and I have another small parted-out Mac with several parts available. incuding an oiler that works. TIA

 

[workshop]

I've got a couple of that style of saw, but have never had to mess with the oiler. However, it might be that you need to remove the engine assembly in order to remove the oil pump assembly. I believe that the pump is driven off a worm gear from the crankshaft and the pump teeth are probably plastic and worn off enough not to pump.
I may be incorrect in my thinking though. Just theory.

 

[Wood Doctor]

I've got a couple of that style of saw, but have never had to mess with the oiler. However, it might be that you need to remove the engine assembly in order to remove the oil pump assembly. I believe that the pump is driven off a worm gear from the crankshaft and the pump teeth are probably plastic and worn off enough not to pump.
I may be incorrect in my thinking though. Just theory.

I think that could be the problem also, but I was hoping instead that the system is just blocked up. Note that the pump is pulling the bar oil from the tank and it makes it to the fitting. I could replace the entire assembly with spare parts that I have on board, but to do that, the flywheel has to be removed. Removing the flywheel is no picnic because there is no room behind it for a typical 3-prong gear/pulley puller to grab it.

What I am wondering is whether anyone has simply blown compressed air through the assembly to remove any gunk that might be blocking the pump? There is yet another tube that connects from the pump to the exit port where the oil is sent to the bar. If that's blocked, the bar oil would never get to its destination. If compressed air could get in there. it might free it all up. WDYT?

 

[workshop]

I'd be careful with compressed air, it tends to blow things up. You might keep after it with carb cleaner, or WD40. I've seen some oil clogs be very stubborn.

 

[Wood Doctor]

I'd be careful with compressed air, it tends to blow things up. You might keep after it with carb cleaner, or WD40. I've seen some oil clogs be very stubborn.

Already did that. OK, then let's get back to basics:

How do you remove the flywheel on a small Mac, such as a 3818?

A typical 3-arm gear/pulley puller will not work. There is not enough back clearance to attach it.

 

[workshop]

Hmmm, my standard way of popping a flywheel is to back the mounting nut off until the top of the nut is flush with the tip of the crankshaft, then put an appropriate sized screwdriver between the flywheel and saw body and pry a little bit on the flywheel. Just enough to put the taper under pressure, then tap the nut with a hammer. You might need an extra set of hands to do this. Works every time for me. Just don't go overboard on hitting the nut or you'll distort the nut threads.

 

[workshop]

I'm looking for a carb kit for a Walbro MDC15 carburetor, McCullough kit number 86463. I checked Walbro's website, they don't list anything.

 

[Wood Doctor]

Hmmm, my standard way of popping a flywheel is to back the mounting nut off until the top of the nut is flush with the tip of the crankshaft, then put an appropriate sized screwdriver between the flywheel and saw body and pry a little bit on the flywheel. Just enough to put the taper under pressure, then tap the nut with a hammer. You might need an extra set of hands to do this. Works every time for me. Just don't go overboard on hitting the nut or you'll distort the nut threads.

Well, that's worth a try. I can attempt it with the 3516 that I already have parted out and see if that works. I tried using a shop-made puller and it broke apart before the flywheel came loose. That puppy is really on there.

Meanwhile, I'll see if I can find a source for that carb you are looking for.

 

[Wood Doctor]

I have good news, Workshop. I was able to pull the flywheel and replace the pump assembly with the one on the parted out 3516. It works perfectly.

However, I am not sure that the assembly I removed was defective. The plastic pinion was in good shape and turned easily. I did notice that the felt seal (300295) between the worm and the engine block was missing, so there was lots of play. I decided to make and insert a new seal when I reassembled. The spring presses against the worm, and that's about the only thing that turns it. It's possible that there was insufficient pressure on the worm, so it never drove the pump pinion. Seem reasonable?

Anyway, it took about 2 minutes of running time for the bar oil to appear, but once it did, there's now plenty of flow. Here's a URL to a Walbro MDC15 carb kit:
http://www.ebay.com/itm/Walbro-MDC-...155?pt=LH_DefaultDomain_0&hash=item2eb9b5e0db

 

[workshop]

Glad it worked out for you, buddy. Yeah, that sounds like a reasonable possibility on the pump. Lord knows, I've seen stranger stuff.
Thanks for the info on the carb kit.

 

[struggle]

Here is nothing really new but a little saw I got with the Poulan 655 I picked up a while back. I messed around with it the last two days pulling what is left of my gray hair getting it running and I can say I'm impressed with the power this little thing has. My issue was I bypassed the oil pump (diaphragm stiff, too cheap to buy one) and in doing that I found out in order to get it to oil I needed to prime the lines with oil first and now it oils great or maybe a little to great.

anyways here it is. air-filter cover is off in picture as I was making an air-filter for it.

Sent from somewhere