Another SP-125/101b build

[cpr]

All tightened down and everything fits! No more clearance work. The rear A/V must be replaced, but it's all there (the front one is new).

I have to take it back down again for a thorough cleaning. I have to make a throttle shaft, put in an auxiliary throttle return spring, fab a fuel line, get a new rear A/V, shim out the bar studs, get a clutch bearing, get a chain, and undertake firing and tuning this thing.

Remember that busted starter? Here's why. I said at least 5 of the 7 words you can't say on TV making it blow 195psi. No decomp... How the heck am I going to start this monster .

 

[Jacob J.]

Remember that busted starter? Here's why. I said at least 5 of the 7 words you can't say on TV making it blow 195psi. No decomp... How the heck am I going to start this monster .

That's why I've done the work of installing decomps on the heads of my 101s. It's not worth breaking parts
just to do the macho thing.

 

[cpr]

After this, I might be goin' there, bud. Not too tough to do it, but I gotsa try, hard headed that way opcorn:.

 

[cpr]

Slow progress, but work continues. I found out today that there are 2 different clutch drums that fit these. They are identical except for the bearing od and drum id to hold it. The NOS one I bought doesn't match the bearing I have, so I robbed a future 797 project of its drum and will figure that one out later. I also found a loop in the shop that fits. This will do until I can order up some full square and now I know how many dl's to get.

Any input on how I should seal off the fuel line to the tank?

This thing is getting very close to running...

 

[Brian13]

Looks pretty sweet!!! What about the barbed fittings, like the 797?

 

[cpr]

Repped you Brian, I forgot about those. Might have to see if I can find some and if they fit.

 

[Brian13]

Now that I think about it I think the 797 has the hole in the tank too. Its the 890 I was thinking of. Oh well you knew what I was talking about.

 

[heimannm]

Bob Johnson has the fittings, but not the sealing washer. I expect you can find a decent substitute easy enough. Fitting is 53675 and should cost less than $5.

Mark

 

[cpr]

I couldn't use the fittings. On the older line, you can split the tank to tighten it, but not on this. I used JB Weld instead. Crude, but it works.

The carb is all in. I need to hook a throttle return spring from the plate to the lower left bolt hole at the carb face. I'll make a bracket to do that.

Ignore the mess on my bench...

I got the bar spacers made and put in, too.

I have to finish the fuel line, throttle return spring, check the bar for oiler passage and tensioner (EDIT: Looking at the picture with the bar plate behind it, I might just be golden), and get a stud for the air filter cover.

Oh, and plug in the kill switch...

and, sooner or later, replace the rear a/v mount...

and order a different chain to permanently use on the saw.

Dang those details kill you.

 

[cpr]

DO NOT BUILD ONE OF THESE.

Yellow fever and the expense involved make you crazy when it gets close to being done. I'll never do another one like this :msp_thumbdn::liquor::skeleton:.

Anyway, the cover is mounted on the carb (fit is okay, at best). The screw-down stud on the cover had to be drilled and tapped for 1/4-20. Pictures later. Fuel line is (was) on, throttle return spring interfered with the throttle shaft on the left side so I moved it to the right. The throttle shaft is too weak though, it won't go WOT, so I have heavier wire to make another one. Ignition kill is hooked up...

SOOOO brutally close... Wanted fire today, but now it looks like the weekend.

 

[leeha]

Building one of these saws is definately not for the novice.
There is a ton of thought, hours and patience as well as
money to get it all done and fit properly. Then hope it runs
like you expect it to.
I took a brake on mine do to a problem with the HL360 carb.
The carb kept running out of fuel at an idle. And i still can't
figure it out.




Lee

 

[cpr]

You got it Lee. I'm far from the level of some folks here (you included), but this one has been tough (and I didn't even do the port work). I've enjoyed the thinking, learning, and hours spent getting it this far, but I haven't proven anything beyond proving you can spend gobs of money creating spacial relationships. It may not even run for all I know :bang:.

I sure have made a pile of potential garbage out of vintage magnesium that I value as much as anyone. A year ago, I would never have so cavalierly tossed a 125 AF cover in a vise to drill and tap it... You might say I'm "committed" at this point :biggrinbounce2:...

I know I'll never attempt this again, even if it runs great. My other 101 will be a bolt-in deal on a hard-tail frame...

The worst part is, for the outlay, it isn't that pretty either. More Pete "Duct tape is OK if it's fast" Robinson than Ed "Chrome and Fiberglass" Cortopassi (those who get the obscure digger references are A. drag racing nerds or B. old !).

 

[ozflea]

Well fellas sounds you's have stepped up to the challange and won i built 3 of them they get easier with experiance the first one a bit of a pain but worth the effort.

Even Bob Liston the fella who taught me at the Mac school had never seen this done and he loved it which made me feel kinda happy

McBob.

 

[cpr]

Thanks Bob. You were the pioneer in this deal, not me. I saw the video of yours and felt I had to try.

 

[ozflea]

Thanks Bob. You were the pioneer in this deal, not me. I saw the video of yours and felt I had to try.

Go have some fun with it i did at first they laughed but then well ..................................

McBob.

 

[Brian13]

When you have it up and running, I am sure all the frustration will seem worth it. Things always seem difficult the first time around. Pretty sure its going to be badass when it done.

 

[cpr]

Go have some fun with it i did at first they laughed but then well ..................................

McBob.[/QUOTpenE]

Pencils can get sharpened quickly, can't they?

 

[cpr]

When I get back out to the shop, I'll make throttle linkage #4. Damn things have to be dead on to work right and I'm not there, yet...

 

[cpr]

The fifth throttle linkage finally gave me the travel I was looking for...

and with that, assembly is done.

I filled it up with lube and fuel and braced myself...

On the third pull it touched off the prime I'd given it, ran for a second, and then the fuel pump caught up to the impulse and flooded it. I mean FLOODED.

I pulled the plug and roped 3oz. of fuel all over my leg. I could see every impulse sending geysers of fuel from every jet in the carb. Something inside isn't right, but I'm really close now.

 

[1375619cm3]

Thats a LOT of fuel in a hurry. :msp_confused:

But it looks sweet!!!