Author Topic: Connecting rod bolts on McCulloch 125 SP  (Read 2375 times)

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Offline 660magnum

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #10 on: April 28, 2014, 01:59:55 pm »
Warm the case up with a heat gun and the bearing should come out easily
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Offline super44

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #11 on: April 28, 2014, 03:28:41 pm »
Thanks for the reply!  Instead of working like I should be I spent some more time with this one and found that if the rod was part way out the intake the crank could turn and line up with a small recess in the case.  That let the crank come out of the case.  Cylinder could be a little better but should run.  Same can be said of the piston if I put new rings on it. Also found this one had a thread insert "heli coil" for the spark plug that the end of was sticking out into the combustion chamber. I don't think I'm the first one in here.

Offline Al Smith

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #12 on: April 30, 2014, 07:28:30 pm »
You have to disconnect the rod cap,don't loose the needle bearings now .Shove the piston clear up forward in the cylinder .

The crankshaft has to be oriented just so so come out the side .

If I can find a picture I'll make another post .

Offline Al Smith

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #13 on: April 30, 2014, 07:52:35 pm »
This is about the best I can do .If you look at the picture which I'm sorry is blurry you can see an area on the flywheel side with a
cut out on it .This is where the crankshaft slides out .The bearing is housed in the crankcase/ignition cover .

Offline Al Smith

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #14 on: April 30, 2014, 07:59:20 pm »
I might want to point out that McCulloch bearings are not heat  shrink fit like Stihl .Just tap it  lightly with a wooden mallet,soft plastic hammer something .No brass hammers now .

Offline super44

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #15 on: April 30, 2014, 10:00:43 pm »
The cylinder is pretty good but the piston needs to be replaced now that I look at it better light.  How much is to much to pay for a piston with rings for this crome plated 125?  The crank bearing seem OK but should I replace then since I'm already in there??  All my banging on these is done with a 2 sided rubber mallet, as I would like to not destroy anything. Thanks for the replys!!!

Offline Al Smith

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #16 on: May 02, 2014, 09:21:45 pm »
So how bad is the piston? It doesn't have to be perfect to work .


If you can find one at all it won't be cheap I'll tell you that .

This is a before and after pic of a piston the damned thing swallowed part of the choke linkage .Sucked it in through the center transfer .I just lap sanded it out with 40 micron diamond lapping paper and WD 40 .

Offline KilliansRedLeo

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #17 on: May 04, 2014, 09:09:57 am »
Neat trick Al, I'll remember that! In the 'before' shot my thoughts were 'trashed'!
"When the people fear the government...you have tyranny....When the government fears the people....you have liberty"

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Offline mcbob

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #18 on: May 04, 2014, 08:42:23 pm »
So how bad is the piston? It doesn't have to be perfect to work .


If you can find one at all it won't be cheap I'll tell you that .

This is a before and after pic of a piston the damned thing swallowed part of the choke linkage .Sucked it in through the center transfer .I just lap sanded it out with 40 micron diamond lapping paper and WD 40 .

Just as well I squirreled away quite a few Al ..............................
I am a idiot so my pics disappeared.

Offline super44

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Re: Connecting rod bolts on McCulloch 125 SP
« Reply #19 on: May 05, 2014, 08:50:35 am »
So how bad is the piston? It doesn't have to be perfect to work .


If you can find one at all it won't be cheap I'll tell you that .

This is a before and after pic of a piston the damned thing swallowed part of the choke linkage .Sucked it in through the center transfer .I just lap sanded it out with 40 micron diamond lapping paper and WD 40 .

Just as well I squirreled away quite a few Al ..............................

mcbob, old buddy old pal!!!

 

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