Chainsaw power

[Terry Bentley]

Anyone want to take a guess at which model McCulloch this chainsaw this is? There is only one right answer. First one that is correct gets an ATABOY from Dave.




Dave will even include a Roundtuit if you can correctly identify both the engine model and make of this chassis.

[Mark Loraine]

I seem to recall it to be a model 77.

https://www.acresinternet.com/cscc.nsf/e...enDocument

[Terry Bentley]

Sorry, you loose. Not even close. Do not pass go do not collect $200. Go to the back of the line.

Maybe you will have better luck with this one.

[Terry Bentley]

OK, seems nobody is all that interested in identifying old stuff. The first picture at top of thread is none other than a model 55. Not all that exciting, I know. It was manufactured right after the more famous D44 came out. This model 55 was available for one year in 1957 and immediately superseded with the Super55 the next year. The direct drive D-44 was manufactured from 1956 thru 1958.

The D44 and 55 saw powerheads are identical. The difference is this model 55 is gear reduction, instead of direct drive. Both saws are 4.4 cubic inches in displacement. IF you were to build a Mc10, this is one of the only two models with correct side cover, cylinder head and top air shroud. Change out the block and crank, or swap the shrouds over to the Super 44A/55A or I-70/80 models and have a bonified true original Mc 10. Or keep it as is and have a look a-like Mc10 with less displacement.

The very first Mc10 kart engines sold were Super44A/55A identical to the saw. As sales increased, they were replaced with the 1-70/80 saw powerheads. With exception to the intake manifold, there was no difference between the saw powerhead and kart engine, except with the availability of a thin ring piston.



The D44/55 has a 2 inch bore and 1 3/8 stroke. Otherwise it looks when assembled, just like a real Mc 10. The one pictured here for your enjoyment is actually serial #55-86. That means model 55, and #86 off the assembly line. I also have another matching saw serial #55-7682 that is mostly complete. I am still holding out to find a few more parts, like 1/2 inch chain and maybe a bar to finish one of these out. I stole the Mc10 only parts from these two, but will be replacing them with the newer model parts which are very common and directly interchangeable. Then have a cool working chainsaw to cut firewood for the winter. 

You will notice this is the first generation of these style saw powerheads and the fins are rounded on flywheel side. This is only on these two models. The exhaust ports are also machined square instead of round for all of the other saw and kart engines except for the Mc30 and chainsaws I-76/86. If you are wondering what all of this information is good for, well probably nothing. But now at least you know.

Since you now know something about the engine in question, ready to take a wild guess to what kart it is on?

[Terry Sullivan]

Terry,
My two cents on the MC-10:
Pretty sure they didn't go to thin rings until the MC-10 Power kits.
I haven't seen any blocks other than 1-70, 1-80, even on a prototype MC-10 i used to have.

My favorite engine, as we had one on a Bug Wasp in 1959!

t

[David Luciani]

hmmm, 
i'm a little lost here terry b.
i thought that the d44 was the only parts saw to use on the mc10 clones for PARTS ONLY.
they are NOT a complete mc10.
seems the early d55 also have those parts?
i am too lazy to look up the d55 specs but is the crank is the same as d44 also?
on d44 the crank con rod bottom has only 22 bearings unlike the later mccullochs which have the classic 24 bearing set up.

they also are a shorter stroke and smaller piston.
perfect for mini bike or play kart motors
thats something i have to do thats on back burner.
i have a few d44 short blocks saved for that idea.

a final note the mc1-80 i believe was before the mc1-70.
in a few extremely rare cases you will find them fitted with mc10 everything.

finally, 
A story i heard? read? about the mc1-60 and possibly the mc1-80 as to why they changed the heads.

on the mc1-60 it was an early standard saw with the head reversed from what we see as normal.
no square access hole and black cover plug , just a nice smooth yellow top.
the next year it was flipped around on all saws .
the was because the spark plug was to close to operators hand in original location.
in the right conditions you'd get "rapped" in the hand with the engine spark.
the mc5 kart motors all had the smooth tops .
on the mc10, its never been clear to me if the spark plug rap was the culprit on the switch to side plugs.
 very possible or it might have been lets make everything standard in casting to save money.

ok that's enough for now i really should be getting things done.
hope this helps people know a little more about this stuff,

dave l 

[Terry Bentley]

Dave I think you may have misread some of the things I wrote. There is no D55, it is designated 55. The D44 and model 55 are identical except for the 55 has gear box added instead of direct drive. Both of these saws are the only ones with the correct flywheel cover, cylinder head and top air shroud. You change the block and crank assembly(rod/piston) using the rest of the D44/55 parts, or use flywheel cover, cylinder head and top air shroud on a Super44A/55A, 1-70/80 powerhead.

You can reverse engineer your leftover parts D-44/55 powerheads and install the later Super shrouds and head, then have a functioning engine again.

The 1-70 and 1-80, direct drive and gear box respectively were both introduced in 1959 replacing the Super44A and Super 55A. The information on Acres site is mostly accurate but there are plenty of mistakes.

The reversed spark plug chainsaws are the standard series models D30, D36, 1-40, 1-50 and 1-60. 1-60 is a standard series with gear reduction and 1/2 inch chain.

To further confuse matters, the D30 had 4 intake ports and two exhaust ports. The D36 had 4 intake ports and all three exhaust ports. The 1-40 had 4 intake ports and two exhaust ports. It basically replaced the D30. The 1-50 had 4 intake ports and three exhaust ports. It replaced the D36. The 1-60 was the same as 1-50 but had tapered crank with gear box added.

One other difference is the D-30/36 had needle bearings on both sides of crankshaft, as the newer models only had needle bearing on PTO.

This should help clear up everything now.

You still got any 1/2 chain? Maybe a bar of two the chain fits? I have that model 55 serial #86 (pictured above)that is almost ready to go back together. My Super 55A has been doing a great job clearing trees where I built my cabin, but always like to have a backup.

[David Luciani]

thanx for clarity this info is spot on and i am happy its in the forum.
soon as i can i'm starting to work on forum again.
i guess my doldrums lasted longer than expected .
i think first pass will be an updated mc10 clone how to with what has to be done to get a correct mc10.

one comment, the mc1-80 and mc1-70 updated motors have a heavier better balanced crankshaft.
 that was a huge change that included a casting change in the block.
material was added to allow a fly cut inside for crank clearance.
i am going to create some pictures to show the difference.
on the outside its very hard to see but visible. 

i DO have the chain and many bars saved for you. 
been years now but i am not the best at sending stuff to say the least. 
if you were close i'd say just come get it would be faster!
send me a pm with addy maybe i can motivate!
dave l

[Terry Bentley]

So far nobody has tried to identify this kart in the first post. I was figuring at least a few people would take a wild guess.

[Terry Sullivan]

Jimmy Yamane's kart. He built and raced it.