BriggsTwins
New member
nice thats good work too, an hour for both at least depending on his method.
(PROJECT) Rupp Dart restomod
- Thread starter Fast Eddie
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Fast Eddie
Member
Need some help. I'm hand-delivering the cranks to my buddy on Saturday. I won't have time to decide on a clutch, buy it, and ship it here for him to use for mock-up. So can you help me with dimensions? On a .750 Dia. shaft, the standard keyway is 3/16 x 3/16, right? How about bolt size and thread count on the clutch retaining bolt? And an overall length dimension? This motor will have a vertical mounting plate that the crank passes through, which is where I'm having him start to turn it down. The length from there to the end of the shaft is what I'm looking for. Is there a standard size? Any help would be appreciated.
EDIT: Found these specs on an eBay listing for a 6.5hp clone motor. Sound like standard dimensions?
Crankshaft PTO: 2-7/16" x 3/4 Diameter Tapped 5/16 x 24 UNF
No mention of keyway dimensions though.
EDIT: Found these specs on an eBay listing for a 6.5hp clone motor. Sound like standard dimensions?
Crankshaft PTO: 2-7/16" x 3/4 Diameter Tapped 5/16 x 24 UNF
No mention of keyway dimensions though.
BriggsTwins
New member
as far as i know most clutches are 1/4 keyways, dont hold me to that, the measurements you gave are normal for engines,
Fast Eddie
Member
Thanks BT
BriggsTwins
New member
your welcome, as long as it is right
The Product
New member
on my gx 200 clone the keyway was 3/16 and so was my maxtorque clutch
Russ2251
AZUSA:Powered by LAWN-BOY
Tillotson's are not a direct fit.
Also, 3/4" pto's incorporate 3/16" keyways as do 5/8" pto's. Very few exceptions.
Also, 3/4" pto's incorporate 3/16" keyways as do 5/8" pto's. Very few exceptions.
BriggsTwins
New member
i hope he reads this before tomorrow
The Product
New member
yea haha
Fast Eddie
Member
Thanks everyone. I saw a few kart sites with clutch specs. All 3/4 PTO's were 3/16". Cranks are out and heading to the machinist today.
Bummer. Figured I'd have to make some sort of manifold/adapter. Did you make your own flanges (engine-to-adapter and adapter-to-carb) or can I find them somewhere?
On the engines Russ, I was planning to replace the two oil seals, rod bearing assy (needle bearings and liners) and rings. Do I need to worry about the wristpin at all? Rather not go through the work of pressing out the wristpin-I'd rather leave the piston/rod together. Also, you just run the stock reeds, right?
Chatting with USPS online support for an hour!! I'm trying to print a return address label for the cranks and can't get it to print. This "Agent" is a complete knob!
Sorry for the rant.
Bummer. Figured I'd have to make some sort of manifold/adapter. Did you make your own flanges (engine-to-adapter and adapter-to-carb) or can I find them somewhere?
On the engines Russ, I was planning to replace the two oil seals, rod bearing assy (needle bearings and liners) and rings. Do I need to worry about the wristpin at all? Rather not go through the work of pressing out the wristpin-I'd rather leave the piston/rod together. Also, you just run the stock reeds, right?
Chatting with USPS online support for an hour!! I'm trying to print a return address label for the cranks and can't get it to print. This "Agent" is a complete knob!
Sorry for the rant.
BriggsTwins
New member
its cool, and give that machinist props!
Russ2251
AZUSA:Powered by LAWN-BOY
No to all.
Keep it simple.
Carb flanges just need to be drilled oversize until they just fit. Original L-B carbs are a non standard center to center bolt pattern and are mounted using long Phillips head screws (¼x20).
These screws can be used (cut to size) to make studs for mounting of Tillotsons.
To do otherwise would be...to be blunt...stupid. 2 cycle power plants rely on a good seal. Any time seals are disturbed, they must be replaced.
Changing needle bearings is optional...unless engine has excessive wear, I would reuse originals. They tend to last forever.
I would consider this important. Engines should be as closely matched as possible.
Re-ring both engines. Honing should not be necessary and is not recommended. Remember to check ring end gap(s) or all will be lost.
DuraForce uses floating wrist pins. Should not require more than finger pressure to remove them. I would leave them alone unless there is excessive wear.
I did not. I used 0.023" carbon fiber (thanx to Crazycart for this tip).
Compression ratio was also increased (slightly) by removal of head gasket.
Be sure to use Loctite (when/where called for) and torque everything to factory specs.
Fast Eddie
Member
Thanks yet again Russ.
Downloaded the service manual for the Duraforce/R-Tek engines. Saw the pin removal tool in the service parts list so I didn't want to get into seperating the piston/rod. Of course seals and rings are going to be replaced. Both motors looked great. No scoring of the cylinder at all. Both bores have nice clear cross-hatching from the factory.
Any good sources for LB parts? Got the complete parts list I need, including #'s from the LB site, but I can't order from there.
Yes I'll do the head-gasket trick and I'll also be adding the pulse-ports. The manual also lists the specific Loctite product needed, which I'll use.
The 334B requires a pulse-port but is said to be for piston-ported engines..I should still be okay with the 334B though, right?
Downloaded the service manual for the Duraforce/R-Tek engines. Saw the pin removal tool in the service parts list so I didn't want to get into seperating the piston/rod. Of course seals and rings are going to be replaced. Both motors looked great. No scoring of the cylinder at all. Both bores have nice clear cross-hatching from the factory.
Any good sources for LB parts? Got the complete parts list I need, including #'s from the LB site, but I can't order from there.
Yes I'll do the head-gasket trick and I'll also be adding the pulse-ports. The manual also lists the specific Loctite product needed, which I'll use.
The 334B requires a pulse-port but is said to be for piston-ported engines..I should still be okay with the 334B though, right?
Russ2251
AZUSA:Powered by LAWN-BOY
Fast Eddie
Member
You rock Russ.
Closest LB dealer is an hour away...and is a complete d**khead.
I'll post some more pics soon. Hopefully I can get some stuff done on the frame today. If not, I have Wednesday off and plan to get some serious progress done.
Closest LB dealer is an hour away...and is a complete d**khead.
I'll post some more pics soon. Hopefully I can get some stuff done on the frame today. If not, I have Wednesday off and plan to get some serious progress done.
Fast Eddie
Member
Russ2251
AZUSA:Powered by LAWN-BOY
I know.
Fast Eddie
Member
Just a quickie. Got the frame back from the blasters. Turned out great.
(sorry the pics are dark...flouro tubes don't get too bright when it's 14 deg. out)
Removed the cancer on the rear framerails.
BEFORE
AFTER
My welding skills are gettin' there. This is after about 15 sec. with a flap disk.
Cranks are still out...but I'm ready to go.
More coming soon...
(sorry the pics are dark...flouro tubes don't get too bright when it's 14 deg. out)
Removed the cancer on the rear framerails.
BEFORE
AFTER
My welding skills are gettin' there. This is after about 15 sec. with a flap disk.
Cranks are still out...but I'm ready to go.
More coming soon...
BriggsTwins
New member
NICE pictures, keep em coming!!!!
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