McCulloch 790 project...

[sefh3]

You don't know the half of it my friend.



I don't hate you Kyle. Takes a lot more than the stupid moves you've made on AS for that to happen. You did piss me off a couple times, but that's not grounds for hate (that's more of a HS thing). You've spilled beer here a few times too many, and that's why you're on probation. Try not to step on your weenie so much.

Just don't try so hard to impress us. Take part in the tech talk when you know what you're talking about, and limit the 'banter' a bit until you get a firm handle on how men BS with each other. That takes time. I didn't have it down when I was 18. Since you're looking for work, have you tried starting out at a mower/saw shop? Get in on the ground floor.

I wasn't only joking when I said you need to sweep some shop floors, do oil changes, and make lunch/parts runs. Working with some extremely knowledgeable older guys in a shop sure helped me out. At the time, I probably knew more technical stuff than some of them, but in the areas of experience and temperment...........they were all miles ahead of me. Had to swallow my pride a few times. That's a valuable learning experience. Sometimes it's hard to shut up and listen when you're a young buck and your mind's going a mile a minute...

Very well stated, Aaron. I have not followed this thread. Reading and listening to follow members goes a long ways.

 

[Eccentric]

Very well stated, Aaron. I have not followed this thread. Reading and listening to follow members goes a long ways.

Thanks Scott.

 

[promac850]

Went out to try out the new gauges, and they work nicely.

Found I have .010" of clearance for the piston near the top of the bore and about .0072" near the bottom of the bore.

I reckon I'm good. Even so, I will check it several times throughout the build to make sure nothing weird happened to it while it sat on the bench in the sunshine.

What do you all think?

Well, I already know leeha's gonna say "Told ya you don't need them gauges..."

Then again, .010" does sound a bit excessive... I am going to check the measurements again...

 

[cpr]

Went out to try out the new gauges, and they work nicely.

Found I have .010" of clearance for the piston near the top of the bore and about .0072" near the bottom of the bore.

I reckon I'm good. Even so, I will check it several times throughout the build to make sure nothing weird happened to it while it sat on the bench in the sunshine.

What do you all think?

Well, I already know leeha's gonna say "Told ya you don't need them gauges..."

Then again, .010" does sound a bit excessive... I am going to check the measurements again...

Mac specs are .004 - .007 IIRC. Personally, at this stage (if the piston and cylinder haven't already been), I'm looking for at least a .010 piston and rings and shopping for a place to get it bored. Find a snowmobile shop with a good rep, or as a last resort, look up Steve Morris Racing Engines in Muskegon or Ron Brinkman at Van Dyke Engines in Fremont. If you like, I can call Ron and see if he can/is willing to do it. Your neighbor who built the bike-pullers would know a shop that could handle it also.

 

[promac850]

Mac specs are .004 - .007 IIRC. Personally, at this stage (if the piston and cylinder haven't already been), I'm looking for at least a .010 piston and rings and shopping for a place to get it bored. Find a snowmobile shop with a good rep, or as a last resort, look up Steve Morris Racing Engines in Muskegon or Ron Brinkman at Van Dyke Engines in Fremont. If you like, I can call Ron and see if he can/is willing to do it. Your neighbor who built the bike-pullers would know a shop that could handle it also.

So, I need to find a bigger piston and get the cylinder bored out.

.030" oversize would be the next size up, as it already is .020" overbore...

I will have to make several more careful measurements and go from there... if I find .010" clearance consistently after all of these measurements, I will bring it somewhere with someone that can check it again, and from there, figure out if I really do need to bore the cylinder out.

(Getting a hair low on funds now... had to get those gauges, then some more stuff. I guess if I must, I will siphon off a tiny bit from the CU to cover the work. I really gotta get off my ass and find a job...)

 

[promac850]

This cylinder would have to be bored ot make it work. That significantly increases the time it will take to get the 790 together.

Gotta find a .030" overbore piston before I even think of getting it bored.

Time will tell. Been digging and still waiting for a few replies...

 

[promac850]

Okay kart men, would a 2.2410" kart piston work on my saw? It comes with rings, and sounds like it's .030" over size.

I found it... ain't necessarily cheap, but I guess I can't always be as much as a cheap ass I want to be.

I do have some green in the CU. Will have to pick some up tomorrow. (loans owe me for all of the parking fees I paid...100 bucks or more of it was my own grad money... gonna check the receipts on that.)

Meanwhile, as I wait for answers, I'm gonna get my slightly fat ass down to the gas station to get some root beer.

Got back, and a I have a line on a piston... courtesy of another member. Thanks, you know who you are!! Hopefully this line has a hook on the end...

 

[cpr]

Good stuff. Kart pucks can work so long as you have the right rod and wrist pin to go with it. Some had different pins and different rod lengths/crown heights, but I guess it doesn't matter!

Found a place to bore it yet?

 

[promac850]

Good stuff. Kart pucks can work so long as you have the right rod and wrist pin to go with it. Some had different pins and different rod lengths/crown heights, but I guess it doesn't matter!

Found a place to bore it yet?

Haven't looked for someone that can bore it yet... I'll call around tomorrow. Today I am going to check the connecting rod and ensure that's good... and clean up the engine tins.

I'm sure it's fine, but gonna check anyways. I guess I like to use them telescoping gauges. I've measured the bore about 20 times the other day to make sure it really did need to be bored out.

I'm taking my time... I want to have the piston in my hands so I can make sure it fits the connecting rod, wrist pin, and the crown height is the same. Taking baby steps...

 

[slipknot]

So where the piston? Dont give up...this is 103cc McCulloch at stake here!!

 

[jerrycmorrow]

did this project just die? or was it completed? wassup wid dat?

Edit: Never mind, found the followup thread. this thread can go lay down again.

 

[Brufab]

Dang what's the new thread? I'm curious on how the saw turned out as I may buy one