McCulloch 790 build

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Whats goin on?

Any updates on this machine of destruction? Cool plug on the rammstien...I used to listen to there stuff..havent heard any for a while. Yup they are still insane. I'd be worried about my face catching on fire...that would suck!
 
Update time... apologies for taking so frigging long. I don't know why I sometimes make things harder than they need to be.

Got a lot done the last couple weeks. Painting, painting, and a little more painting. Also found gasket material and made gaskets, and got some 1/2" welsh plugs coming in. (expansion plugs)

Here are some pics for you to look at. I don't know if they're worth drooling over or not... but if they are, awesome. :cheers:

Repairing the recoil/clutch cover... found two cracks. Stop drilled one, but not the other only because I could not find the end of the crack. Then JB weld was applied to clean, bare metal.

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Also did the recoil mechanism cover at this time. The repaired clutch housing half was later done with the same satin black paint.

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more in the next post...
 
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Here's the workbench that the tree killing monster has all to itself...

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And here is the ring end gap I just checked a little while ago. .009" I think I have a little work to do...

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So... this thing should bark sometime next week. Not exactly sure when it'll make its first cuts as bar plates are needed and I don't think one bar plate is worth more than 5 bucks... Otherwise, I do have a couple of bars that I can use for the first few cuts. Probably will use the 24" hard nose with a new loop of chain.

Still thinking of a big bar on this saw... 40" sound right? I was going to order that 37" black and yellow McCulloch hard nose with the chain, but forgot to jump on it. Yeah, that would be another 180 ish bucks into this project... But I don't care. It'll be worth it when I get to let it make chips in a giant tree...

Looked at the info that I have, and .009" is within the spec listed by McCulloch. So, I'm all set on the upper ring. Going to go check the lower ring and see what that one comes out to.
 
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Alright... welsh plugs for the lower transfer access holes arrived at the store a while back, so I picked them up and installed them. The first place that I tried didn't have the right ones, so the guy there looked them up and found that Dorman makes them.

For extra insurance, I sealed them off after installation with Threebond 1194.

For those of you that happen to be wondering where to get these, you should be able to find them at an auto parts store. It is Dorman part/item # 550-003 They are called 1/2" concave expansion plugs. I got a bunch of them for later projects. Should be able to work the transfers on several more older Macs. 22 of them are about 7 bucks, give or take.

Pics of parts/assembly will be posted later, when I actually get around to putting it together. Gotta eat supper first, getting hungry over here.
 
Been real busy the past few hours... yes, I took my time on the main engine assembly and the rest of the assembly... don't want to get crap into the engine if I can help it. And yes, you're probably thinking I'm nuts for assembling an engine on a bench covered with stuff like that one picture showed earlier, but as long as Murphy doesn't come around and whack me in the back of the knee with a crowbar, there will never be a spec of dirt or clump of crud in that engine.

Here's some pics for you to look at... I figured out how the points go together (CPR was right, with some studying of the IPL and using some common sense and logic, it really is simple to put together) Got the lower tank half slapped on, along with the oil tank. The points, coil, flywheel, clutch drum, clutch, and all of that are installed. I ordered an air filter off of fleabay today as well. Soon... very soon... :blob2:

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Here's an excellent tip for those that either forgot or never heard of it... throw the crank with the bearings on it into the freezer... it'll make it a breeze to put the engine together as the bearing will slide into the crankcase with a few light taps of a hammer.

I turned it over by hand a couple times, (while lining up the flywheel to the coil to set the air gap) and the compression is already impressive... this one should be very strong, especially considering the rings are gapped closer to the min. side of the spec than the max. side of the spec...

More in the next post...
 
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Also, if anyone has one of these little throttle rod boots laying around, I could use it. One of the boots was torn bad some time ago. Nothing left to seal the air box hole to the throttle rod and keep crap out. Half of it is gone.

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Looking good Kyle.




Lee

Thanks, Lee. Still not quite as pretty as some of the saws you've restored...

But I'm still happy... it is 6 cubes after all... :D

Almost done... got the front handle to install, clutch/recoil cover, bar plates, and the bar/chain... then the air filter hold down bracket needs the nut welded to it and then it needs to be installed. If there was a u-nut or something like that there, it is missing.

Got up at the crack of late breakfast (10:30, I was up past 3 am, stopped working on the 790 at 1:30 am) Had to make some hardware as some of it was missing. She's looking more and more like a saw... it's amazing what a pile of parts and hardware can turn into.
 
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It's all together now (minus two bolts on the front handle that I forgot to install)

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Pulled many times, she popped a few times. Bit me many times as well, even with solid pulls at/near TDC.

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Yep, recoil rope broke. I put a new knot in it and will get back to trying to start it. I also found the carb adjustment screws felt real loose, replaced the o-rings on those and now they feel like they're sealing. Primer works well, and the carb is spitting fuel into the intake like it should. (fouled the plug once so far)

Just finished supper a minute ago, time to get back to work and get this beast to bark...
 
It is looking good, Kyle. I hope you get it running without wearing out yourself. You're young so you should be alright; I have a quota on how many pulls I can do before I have to stop. Ron
 
It is looking good, Kyle. I hope you get it running without wearing out yourself. You're young so you should be alright; I have a quota on how many pulls I can do before I have to stop. Ron

I have a quota too, but I seem to recover from the effort a little faster.

This thing is almost barking... it pops even more often than before. My hand is hurting a little, but I really could care less. I want to hear this thing run.

Buzz sawyer, I can't wait to make a video...
 
If everything is set right it should run. Even if
it's just on a prime. Depending on how you assembled
it. It could be oil flooded. That is if you used a ton of
oil on the engine assembly. Keep pulling the plug and
see what it looks like. Try a new one. It should run.
No need to wear your self out.



Lee
 
If everything is set right it should run. Even if
it's just on a prime. Depending on how you assembled
it. It could be oil flooded. That is if you used a ton of
oil on the engine assembly. Keep pulling the plug and
see what it looks like. Try a new one. It should run.
No need to wear your self out.



Lee

Too late, already wore myself out. I did use some oil in the assembly, but I don't think it's enough to be a problem. Pulled the plug and it was only fuel fouled. I'll buy a new spark plug tomorrow and pick up those bar plates. Hopefully they have them.

.020" for points gap, .010" for coil, and .020" for spark plug. Those are the specs that I found.
 
Looks like the Shop Monkey got himself banned yet again.

When's the boy gonna learn? :confused:

Are you calling the author, promac610 a shop monkey and saying he got banned, or are you talking about someone else?

Cause if the author banned, hes great at building up suspense and leaving on a cliffhanger note.

I really wanted to see this saw run...
 
Are you calling the author, promac610 a shop monkey and saying he got banned, or are you talking about someone else?

Cause if the author banned, hes great at building up suspense and leaving on a cliffhanger note.

I really wanted to see this saw run...

Yah, promac610 has been known for some time around here as 'Shop Monkey' .... he's gotten banned a couple times recently ... I think he's bordering upon a demotion to 'grease pit slug' ...
 

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