My New RedMac Saw

Well, I bought a new (to me) saw that I didn't need, but while I've got plastic Poulans, a Poulan/Husky, a cinder block Mac and a throw-away plastic 32cc Mac, I just didn't have any of the dreaded Jenn Feng Macs. I just had to get one to complete my collection of the most despised saws on AS. So I picked up a McCulloch MS4018PAV, a genuine 40cc Jenn Feng Mac. This thing was dirty as heck and had clearly never seen an air gun. Sorry for the lousy pictures but the lighting was bad:






Look familiar to anyone?



Two piece mag case, strato engine - yup, it's a RedMax GZ4000 in black and yellow.

I like your line,"most despised saws on AS". that is great.

Another one:



There are later McCulloch-branded saws that are clearly also RedMax in 35cc and 40cc, such as the MCC1840B and EB358A, but they've been cost reduced a bit with one piece top covers and the filler caps in the handle are relocated.

I paid a little more than I want ed to for this one, about $100 with shipping, but I'm happy with it so far. The piston seems to be in good shape (two rings), and while the thing is filthy the only real damage I saw is the air filter, which can be repaired until I get a new one.

I've already got a really nice, light 40cc saw in the Husky 142, so I didn't need this one, but I wanted a strato saw. Also, this one has bar oil pump that only runs when the chain is moving. Overall, I'm hoping for a saw that uses less fluids of all types.

I have admired the RedMax saws, and so far the design impresses me. It is light and compact, and the bar studs mount into the mag case. I do not plan on porting it, but I will muffler mod it, and then I'll see how it compares to the 142. This one has an 18" bar with Oregon 91 lo pro chain with 62 drive links. Interestingly, the bar is shorter than the 62 drive link 18" bar for my 42cc Craftsman - the drive sprocket must be set back further. I would ultimately like to put a 16" bar on it, perhaps 0.043" like the 142, but IIRC Brad found the 0.050" to cut faster.

The biggest concern I have about this saw is that parts are not as common and may be more expensive.

You still to add a plastic Mini Mac to complete the flush.

Mark

3000 FPS said:

I like your line,"most despised saws on AS". that is great.

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Hey, all of my saws are cheap junk. I make sure never to talk about it when I'm up in the woods, otherwise the trees might stop making firewood.

That thing's got more buttons,gadgets.gizmos than my wife's Toyota Avalon

interesting, and I've seen dirtier.

luck,greg

Been running a 35 cc Jenn Feng "Mac" for over 6 years now. Despised? I don't think so.

Not inclined to knee-jerk reactions. The saw works great for me, so I treat it well. Can't guess how long it'll last.

For a variety of reasons, it's my go-to saw for anything it can reach through. (I would prefer the strato engine.)

So much for generalizations.

heimannm said:

You still to add a plastic Mini Mac to complete the flush.

Mark

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LOL - I'll stick with my SE2012S. Similar in concept but they moved the carb up top where you can get it.

CTYank said:

Been running a 35 cc Jenn Feng "Mac" for over 6 years now. Despised? I don't think so.

Not inclined to knee-jerk reactions. The saw works great for me, so I treat it well. Can't guess how long it'll last.

For a variety of reasons, it's my go-to saw for anything it can reach through. (I would prefer the strato engine.)

So much for generalizations.

Click to expand...

There are two 35cc designs made by JennFeng - one is an actual McCulloch design with a horizontal cylinder, much like my 32cc. These were made from 32cc to 38cc, with and without A/V. Then there is the RedMax-based strato engined saw. I like them both actually, as both have bar studs mounted into metal - they're both strong saws.

I just took a better flashlight out to the barn to look at the cylinder - it's darn near perfect! Not a scratch on it anywhere, you can see the hone marks on the cylinder, both rings look great and the machining marks are clearly visible on the piston. Look like I lucked out on this one.

I did a lot of cleaning and reassembly tonight. The air filter got repaired with a piece of Nomex paper attached with JB Weld covering the damaged section. The carb was whistle clean inside, but the strato port/valve was really cruddy inside. I made a tool for the D-shaped carb screws, and did a muffler mod. They route the exhaust down to the bottom of the muffler and back up again, and I decided to keep that while enlarging the holes. I did not want to take apart the crimp, so I decided to drill in through the front and make a cover plate to block off the access holes. That worked OK - I used a piece of stainless sheeting I cut out of the housing for an old microwave. I left out the screen for now.

It started up with a couple of pulls - it was really rich, but after turning the screws a bit it smoothed out nicely. Sounds kind of mean with the muffler mod.

However, it's clear it is not oiling, so I'll have some work to do. I need to make a tool to pull the clutch, which I should be able to do tomorrow at work in the machine shop, and then I'll see what the problem is. I did get some oil through with the saw on it's side, so I guess the lines are intact (might be short in the tank I guess). I hope it doesn't cost me in parts - bits for these are not priced like Poulan parts!

Still, not bad so far - I really like the way this saw is designed and I hope the way it works matches up.

Intake port:


Exhaust port:


Blurry muffler:


Air filter repair:

I will say one thing you a very creative at doing things on a budget.

3000 FPS said:

I will say one thing you a very creative at doing things on a budget.

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Thanks! My universe is filled with things that need to be fixed, and has been for along time - all I have to do is look through all the bits of junk I've saved, and the thing I need to fix whatever I'm working on at the moment will probably be in there. Sometimes it just needs to be liberated from whatever it is part of now!

Could you post a picture of that strato port valve. Is it the plastic manifold for the intake? If it is check the O-rings on it for leaks. I had a Red Max GZ 4000 that was run and left to sit with bad fuel and the intake was swelled to the point it wouldn't open. I took it apart and cleaned it well but it had air leaks on the shaft ends. Red Max doesn't sell just the O-ring and the whole assembly was crazy expensive.

I love those small Red Max saws. I have the Ryobi 40cc, and the Craftsman Pro,(Yellow Max). IMO nicest small saw going.

I don't have my pictures with me, but I'll check this evening to see if I have a better one of the air valve. If you look at the 5th one above the air valve is the black carb mount/manifold. Mine was pretty sticky, but I cleaned it up with the air hose and a small amount of carb cleaner, and then I squirted some WD40 into the moving bits and blew it out again. I moves much better now. I did remove the screws with the thought of pulling the shaft out, but it was not interested in coming apart and I did not want to risk damaging it.

I would not think that minor air leaks on the shaft would be a big problem - after all, its job is to pop open above idle and let in a fair amount of fresh air. It seems to me that would swamp any small leaks around the shaft.

The saw seems really nicely designed and made, the parts seem to be high quality, but I think the Achilles heel is going to be parts availability and cost. On the other hand I see a lot of these saws under a lot of brand names, including Talon for down under and some Chinese knock offs. You would think there must be a parts supply around - maybe I just haven't found it yet. Just looking for an oil pump (just in case) I came up with nothing using the McCulloch part number. I did find a document showing a part number conversion to Husqvarna, so maybe they will carry parts eventually now that they own RedMax.

Well, it runs and the oiler is fixed. It's all back together and I'm very happy with it, at least without having cut with it yet (which I'm looking forward to). The oil pump had me puzzled for a bit, since the lines were all clear and the pump seemed fine. But I was ignoring some clues and I figured it out on the second try. First, the clutch tool I made:



Here's the clutch side with the pump cover off:



The pump is very similar to Poulan units I've worked on, with a bushing with a wobbly groove and a gear that spins a shaft with a flat ground on the end. The wobbly groove makes the shaft move back and forth like a piston and the spinning flat acts like a valve. That all seemed fine at first, but the problem is visible on the left side of the pump where that shaft is jammed up against the case:



It's not supposed to be that way - the nylon bushing with the wobbly groove had slid on the shaft, so the shaft was shifted back out of the pump bore. I pulled it out and used a tiny press I have to push it back together. It took some force, so I'm hoping it stays, although I don't know how it got that way. Probably some crud got jammed in the worm gear. Anyway, pumps great now!

I decided to keep the "(18")" bar on it, since it's actually only exposed 16" from the case. The 18" bar on my Craftsman projects 17.5", and the 16" bar on my 142 sticks out 14.5". Go figure. It's not worth the cost of changing it, and the saw is only 2cc smaller than the Craftsman anyway. And this uses 62DL 0.050" LoPro, same as the Craftsman and one of the most common chains. The chain that came with it was sharpened on a grinder and I'm not thrilled with the job, but it isn't dull either. It's 91PX chain.

Hopefully soon I can run it and do the real tuning. I think it was a decent buy for $100 including a nice case and the scrench.

I like the way the manifold is designed on this Mac saw. Its looks like an improvement over the Red Max design. Both my Ryobi and my Yellow Max have the manifold with the 2 round openings that go into the air filter. Both of them have distortions in the foam on the filter where the manifold attaches to the filter. I don't know if the engine sucks the foam in or if its just the way I've put the filter back on when I replace them. So far though I haven't seen any dust behind the filter.

Also, that Mac has a differant recoil cover with more openings. Should allow for more cooling air. I like that saw. Now I'll have to keep an eye out for one.

I also run an 18 inch bar on my Ryobi with Woodland Pro 30LP. I have a 16 on the Yellow Max. The 14 inch bars from Wildthings and small top handled Poulan/Craftsmans fit these saws. You will like that saw. I've burried that 18 inch bar just to see how the saw would handle it and did a lot better than I would have expected.

The only real problem I have heard about on these saws is the recoil springs, and the starter paws. I think they should be available from Red Max.

Interesting - I saw the manifold/air valve looked different on the RedMax GZ4000 IPL, but I thought maybe that was because this is a little older (it appears to be from around 2005). The label says it's made in Taiwan, but it is so similar to the GZ4000 that I have to believe it is made out of mostly the same parts. Later McCulloch branded saws of this basic design diverged a bit more. I'll have to look into the difference in the air valves.

Well, I've had an annoying head cold the last two days and took off from work. I played with the saw a little bit, and discovered the bar that was on it was incorrect. If fits but the two holes don't connect to the bar groove so it won't oil in spite of having fixed the pump. The saw is supposed to use an A041 mount bar (Wild Thing bar) with a 62DL chain. I don't know what this bar is for, but is uses a 60DL chain. So I slapped a coat of paint on the old bar for my Craftsman and got a new loop of 91PX. It doesn't look too bad:


Here's the unknown bar after modification:


I used a 5.5mm chain file to cut it, which was actually quite easy.

My next challenge will be tuning - I didn't feel up to doing more than a couple of cuts, but I had a hard time hearing any burble at all. I had to resort to finding the max no load rpm and then dialing rich from there. I'm not sure if/why a strato saw would be different in that respect. I'll have to try again tomorrow maybe. The saw does start right up, idles great and revs quickly. It's definitely a little lighter than my 142, I'll have to find a scale some time.

Hey Chris, your mystery bar looks like a Oregon A095 mount. I have one that Baileys modified simarily to your picture. The thing that I don't understand is the symbol next to OREGON in your picture that looks like the narrow kerf symbol on my Oregon Micro-Lite bar which is a .325" pitch, .050" gauge bar. Does your bar have a three rivet sprocket tip ?