Another SP-125/101b build
- Thread starter cpr
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cpr
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Don't know 24d, never seen a dealer-installed one. I'm cottoning to Ron's idea to just bolt it to the cover and call it good.
Got my sloper this morning. When I walked in and told him what I was after he said "Sure. You want aluminum or magnesium?" :hmm3grin2orange::hmm3grin2orange::hmm3grin2orange:
I was tempted to buy both, but don't need one for the other build I'm doing. I bought the aluminum one on the left. He was pretty adamant that they're in the business of doing the work and racing, not selling parts, but if he had some extras that weren't being used, he'd move them along. He did say that Mac rods are getting tough to find and the price is climbing.
The kart room had mostly Mac and Comet stuff. Spied one bender on the shelf, too. That was boring relative to the main-shop, though. Vintage sportscar nirvana. I didn't want to push my luck by snapping a bunch of photos, but there were several Group C/GTPs under tarps, several F3000s, A Lola T70/Chevy coupe, March can-am, a Corvette Stingray, Bill Elliott Ford Taurus Cup car, Intrepid/Chevy GTP, Shadow DN4 Chevy can-am (the last car to win the original balls-out can-am), a couple Cobras, a couple 50s Maseratis... The engine room was mostly big Chevys getting massaged, but I did see a V12 block of some sort on a stand getting worked on, too.
So, with that, this build is off to the races. Some small parts to get (av mounts, clutch, carb kit) and I have to whack the airbox, but we're rollin'!!!
Got my sloper this morning. When I walked in and told him what I was after he said "Sure. You want aluminum or magnesium?" :hmm3grin2orange::hmm3grin2orange::hmm3grin2orange:
I was tempted to buy both, but don't need one for the other build I'm doing. I bought the aluminum one on the left. He was pretty adamant that they're in the business of doing the work and racing, not selling parts, but if he had some extras that weren't being used, he'd move them along. He did say that Mac rods are getting tough to find and the price is climbing.
The kart room had mostly Mac and Comet stuff. Spied one bender on the shelf, too. That was boring relative to the main-shop, though. Vintage sportscar nirvana. I didn't want to push my luck by snapping a bunch of photos, but there were several Group C/GTPs under tarps, several F3000s, A Lola T70/Chevy coupe, March can-am, a Corvette Stingray, Bill Elliott Ford Taurus Cup car, Intrepid/Chevy GTP, Shadow DN4 Chevy can-am (the last car to win the original balls-out can-am), a couple Cobras, a couple 50s Maseratis... The engine room was mostly big Chevys getting massaged, but I did see a V12 block of some sort on a stand getting worked on, too.
So, with that, this build is off to the races. Some small parts to get (av mounts, clutch, carb kit) and I have to whack the airbox, but we're rollin'!!!
cpr
Addicted to ArboristSite
Not a lot of time tonight. Just wanted to get the engine closed up to keep dirt out.
Quick shots of the transfer porting.
The exhaust is merely widened to remove the scallops and raised slightly. That's it.
Mounted the sloper and wanted to set the carb on to keep trash out and got an unexpected surprise. I added the gaskets after, but that didn't help. What am I missing here?
Anyway, closed up for tonight.
Quick shots of the transfer porting.
The exhaust is merely widened to remove the scallops and raised slightly. That's it.
Mounted the sloper and wanted to set the carb on to keep trash out and got an unexpected surprise. I added the gaskets after, but that didn't help. What am I missing here?
Anyway, closed up for tonight.
Brian13
Addicted to ArboristSite
Is there a spacer that can go there? Or maybe supposed to use a different carb? Just guessing out loud.
petlele7456
ArboristSite Lurker
Watching and learning...I have two MAC 10's and one MAC 40 (or vice versa, can't remember right now); I will try to slip one of those in a D-44 or Super 44 over the winter just for fun.
cpr
Addicted to ArboristSite
Yellow fever has a mutation in the virus...
They're multiplying and misquoting from very different threads now.
They're multiplying and misquoting from very different threads now.
CPR, you should have gone with the magnesium one. Seriously, I wish I could help you but I can't. I know my double pumper will not fit without reversing it. Mine looks like it will clear one plate only. Ron
cpr
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I don't know, Ron. The kart guys put the pumper up, but Bob showed it pumper down. No way this fits the airbox pumper up. Further, by the looks of it, I may not have to worry about that rear av mount as it might not fit in there either with the carb. I guess I'll have to make some sort of a spacer.
CPR, I'v went though some notes of mine and I'm pretty sure that's correct. I was my understanding that the factory kit came with a small piece of metal with two threaded holes in it, you drill the cover, then screw the bolts into the supplied threaded plate (or washers and nuts), use the 101 cover, it's metal vs the sp125 aluminum cover.
Brian13
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I was going to suggest turning the carb upside down, but didnt know it you would be able to. Does it have more than one impulse port to do that?
cpr
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Brian - I'll get pictures when I redo the carb of how the impulse gets to the carb, but you can bolt it up in all four positions and it will work.
Got the block on the ported one drilled for the bumper and the manual oiler this morning and bolted up the oil tank. I discovered though, that the manual oiler won't be available. There's no way to get the rod around the carb to the button and the button's carrier may get cut away ultimately. So, I'm solely reliant on the auto oiler for this. I have a 36" bar for it, but I really would like to find a 32" belly bar for it. In the meantime, I plugged the passage with some JB Weld. If I ever back this saw down to a conventional intake, the passage will be there.
Last goal for the morning was to pull the flywheel and put on the starter pawls. The pack of studs I bought are the wrong size, though. The pawl won't fit the stud and I doubt the stud would press into the flywheel. I got the right ones coming.
Got the block on the ported one drilled for the bumper and the manual oiler this morning and bolted up the oil tank. I discovered though, that the manual oiler won't be available. There's no way to get the rod around the carb to the button and the button's carrier may get cut away ultimately. So, I'm solely reliant on the auto oiler for this. I have a 36" bar for it, but I really would like to find a 32" belly bar for it. In the meantime, I plugged the passage with some JB Weld. If I ever back this saw down to a conventional intake, the passage will be there.
Last goal for the morning was to pull the flywheel and put on the starter pawls. The pack of studs I bought are the wrong size, though. The pawl won't fit the stud and I doubt the stud would press into the flywheel. I got the right ones coming.
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cpr
Addicted to ArboristSite
Mocked everything up tonight. There's a lot that has to happen in a very tight space. #1, the rear av mount must be used. It's just too floppy otherwise. It will have to be shimmed, too because the intake hits the bottom of the fuel tank. I believe I'll mount it down on the shroud and shim "above" it to keep the "u" out of the way of the carb. Looking at Bob's, I see he did the reverse, so maybe it'd work? #2, I'm not sure how the heck Bob fit the carb in there. I can make clearance side-to-side, but it measures out just barely fitting under the cover now. If I put in a spacer, it will be too tall. I may be forced to window the shroud and cut a fin or two on the block to keep the carb down. The more I think about it, the more convinced I am of having to do it. BTW, for reference, the BDC is 2 3/4" long. Brad, I know you wanted to use the big Tillotson. With that adapter block, I can pretty much guarantee you won't get the cover on and you may have to whittle on the adapter to fit between the vertical walls of the fuel tank. I hope I'm wrong, though.
Gonna sleep on it and hope Bob will weigh in here. Choppin' up a tank tomorrow.
Gonna sleep on it and hope Bob will weigh in here. Choppin' up a tank tomorrow.
Eccentric
Mister Wizard
I'm wondering if you could adapt a manual oiler pump from some other saw. Some Homelites (of the XL700/800/900 family) and other saws had a manual oiler pump that bolted to the saw (with a feed and a pressure line attached). The Mac 15 had a self contained (not incorporated into the carb box/rear handle or other casting) manual oiler pump, but it's a long sucker that'd be hard to fit into what you're doing. The millilng guys also use manual oiler pumps that you may be able to adapt to your project. Just thinkin' out my butt....
Another option might be the manual oiler from a large Pioneer (P-60-62.) Those are kind of a "universal" manual oiler.
cpr
Addicted to ArboristSite
Had a little time this morning, so I put the pawls on the flywheel and moved the starter to the kart cover I have and figured I'd see how much compression I had.
Never found out...
I've got a short-snout starter here. Guess I'll fix that tonight and see what else I can break
opcorn:...
Never found out...
I've got a short-snout starter here. Guess I'll fix that tonight and see what else I can break
opcorn:...
OUCH.
I haven't done that yet.
I haven't done that yet.
cpr
Addicted to ArboristSite
Looking at the cracks, I think it had some damage already, I just finished it off when the gauge tried to get above 150...
My non-DSP 101B had one of its legs broken so I am still toying with a DSP conversion; IIRC it measured in the 180s psi. My other is 196 psi. Ron
cpr
Addicted to ArboristSite
Had a heck of a time sleeping last night convinced I was missing something here. When I woke up, I knew what it was.
Here's what's causing the interference problem with the carb. Every kart block and every saw block from the CP-125 all the way back to the D-44 and including the 90-Series/250-type saws have had identical architecture. The Super Pro block is different. Look at this picture I posted earlier of the 101.
The intake surface is scalloped into the block towards the cumbustion chamber. This is how every other saw and kart block is. It will fit in a SP frame, a hard-tail Super Series frame, and a 90 Series frame.
Now look at my SP-125c.
The intake surface has the same shape, same bolt pattern, but the surface is parallel to the bore. The cooling fins run right up under and abutt the intake until they stop for the clutch. It keeps the carb up off the fins and that's why Bob's works. The Super Pro saw blocks only work in the AV chassis. You cannot bolt them into a hard-tail Super Series saw or a 90 Series saw. The tank wells would attach, but none of the handles would line up.
Looks like I'm going to use multiple approaches to fix this. Thicker gasket under the sloper, thicker gaskets at the reeds, an aluminum spacer, and probably clearance work at the shroud and block coupled with beveling the carb (last resort) to get it to fit under the air cover.
Here's what's causing the interference problem with the carb. Every kart block and every saw block from the CP-125 all the way back to the D-44 and including the 90-Series/250-type saws have had identical architecture. The Super Pro block is different. Look at this picture I posted earlier of the 101.
The intake surface is scalloped into the block towards the cumbustion chamber. This is how every other saw and kart block is. It will fit in a SP frame, a hard-tail Super Series frame, and a 90 Series frame.
Now look at my SP-125c.
The intake surface has the same shape, same bolt pattern, but the surface is parallel to the bore. The cooling fins run right up under and abutt the intake until they stop for the clutch. It keeps the carb up off the fins and that's why Bob's works. The Super Pro saw blocks only work in the AV chassis. You cannot bolt them into a hard-tail Super Series saw or a 90 Series saw. The tank wells would attach, but none of the handles would line up.
Looks like I'm going to use multiple approaches to fix this. Thicker gasket under the sloper, thicker gaskets at the reeds, an aluminum spacer, and probably clearance work at the shroud and block coupled with beveling the carb (last resort) to get it to fit under the air cover.
