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ezcome-ezgo
G'me sumthin to write on
Whoop!
KartFab
Active member
ooo im gunna watch this video over the weekend! He has so much good information, but 90% of the words that come out of his mouth are not even relevant to what he is talking about. Its worth sorting through all of it though to get to the good stuff Jodysays!
mckutzy
Well-known member
What is the summary of the show??? What does he explain about???
KartFab
Active member
CLEARANCING = HIGH RPM CAPABILITY
below is a summary of how he clearances these engines per AKRA racing with stock rod on their gx200 clones "U-Build It"
BORE
pistons in the hole he has seen maybe 3 thousands in the hole, they vary, measure at the top of the piston and bottom of the piston top, take the lowest number and that is your in the hole number
piston to side wall clearance should be measured with a micrometer (for the piston) and dial bore gauge (for bore) should be about .0035"-.004" difference ideally. If it is more, of if the cylinder wall is damaged you should get an oversize piston.
do not use a dingleberry/ball hone to make a cylinder that is out of round 'round'. a sunnin three or four stone hone will restore it back to round, not a ball hone.
When you measure the bore, you must do it with a torque plate for the most accurate results (torque to 220 inch pounds). He also recommends doing this with the side cover on as well. He starts with 180 grit, then moves up to 320 grit, then uses a plateau hone to finish it up. You want about a 45 degree angle of crosshatch. This allows for proper break in, and oil retention.
LIFTER BORE
lifter bores he likes to hone these as well for oil retention. about 400-500 grit. Same angle, 45 deg.
wash block he uses a parts washer to clean it out. then checks ring gap
RINGS
tensioning if you dont know how to de-tension the rings, just buy de-tensioned rings. Leave the TOP not detensioned, only detension the second scraper and the corrugated oil ring. Low tension rings can flutter at 7-8k rpms without holding compression, which is why you should not have a detensioned top ring.
ring clean up Rings out of the box can have rough edges and build up. Take a scotch-brite pad to clean them up around all side. You are just trying to clean up the roughness, not sand or apply lots of pressure. This removes the bits that break off the ring on start-up that score the piston.
end gap measurement Top ring should be .006"-.008", second ring .008"-.010" Put the rings in the block down just a tiny bit, use the piston to push it in and measure with feeler gauge. if too large, get file to fit, if too small, file to fit. Check ring gap at top of cylinder and about 3/4 of the way down the cylinder. Squirt a bit of WD-40 in there to avoid scratching when measuring ring gap. when the cylinder gets hot, the pistons could butt together at .002"
CONNECTING ROD AND CRANK
torque to 120 inch pounds
use micrometer and dial bore gauge to check oil clearance, which should be about .0025" to .003"
plastigauge vs dial bore and micrometer plastigauge tells you clearance in one spot, but dial bore will do that and tell you if it is out of round. Out of round rod and crank will start to gall the crank journal.
crank journal journals may come out of the factory big, so you have to make sure you polish it down to get the proper oil clearance. You can use emory cloth to polish it down with a 300-400 grit emery cloth.
crank clearance casting hump just above the journal rubs on the connecting rod. Take a dremel and knock it down.
connecting rod dont use a ball hone to clearance it, which makes oil spread to the outside edges of the rod journal. Use a stone hone for that to keep clearance even. get that cross hatch on it (we are talking stock rod)
wrist pin .001 to .0015" clearance. He runs a ball hone through this just to get the cross hatch.
CLEAN
spray down with carb cleaner, wash with parts washer, and maybe spray it with WD-40 on it to prevent flash rush. Clean everything a lot. Can use soapy water and wash, then add wd-40. If you want it cleaned right, use a sonic cleaner. You cant clean the block enough. Get it super clean.
After that, get a 25% mineral spirits, 75% ATF fluid. wipe down. Clean clean clean clean.
ASSEMBLY
put piston in with the arrow pointing down, oil dipper hole in rod points down, dipper points down.
rings go in with a ring compressor, Popsicle sticks can mess it up.
assembly oil not needed, use whatever oil you will be using to break the engine in.
use a torque wrench or you will end up like that one guy on this forum. Harbor freight click torque wrenches are CRAP, and can snap bolts. IF you are going to use one, just break it in by making it click a crap-load of times at max torque setting on a bolt that you don't care about.
TORQUE SPECS
120 inch pounds stock con rod
170 inc pounds arc billet rod
220 inch pounds cylinder head
200 inc pounds side cover
FAVORITE VIDEO 'QUOTE' "im not saying this is illegal, but it is illegal. You can get tossed out for it.... if you dont cover it up well. Dont come crying to me if you get kicked out for this, but you can cover it up"
MISC QUESTIONS THAT MATTER
Q. Can you run a piston with no or a short skirt?
A .You want it at around 3 thousandths. You need tighter clearance.
Q. Stock piston to sidewall clearance?
A. Almost all stock pistons run about .004" to .0045" wiseco and shorter have tighter clearances, usually around .003"
Q. How far out of round can the crank journal be?
A. .001"
Q. Can i get a copy of the torque spec sheet that comes in the U-Build It Engines? (what Jody was referring to throughout his video)
A. Yes, call and ask for it and we will email or fax it to you.
Q. Does the size of the oil hole in the rod matter?
A. Yes. Don't make it a lot bigger. Just deburr and make it round. Too big and it can affect the integrity of the rod.
THE END
below is a summary of how he clearances these engines per AKRA racing with stock rod on their gx200 clones "U-Build It"
BORE
pistons in the hole he has seen maybe 3 thousands in the hole, they vary, measure at the top of the piston and bottom of the piston top, take the lowest number and that is your in the hole number
piston to side wall clearance should be measured with a micrometer (for the piston) and dial bore gauge (for bore) should be about .0035"-.004" difference ideally. If it is more, of if the cylinder wall is damaged you should get an oversize piston.
do not use a dingleberry/ball hone to make a cylinder that is out of round 'round'. a sunnin three or four stone hone will restore it back to round, not a ball hone.
When you measure the bore, you must do it with a torque plate for the most accurate results (torque to 220 inch pounds). He also recommends doing this with the side cover on as well. He starts with 180 grit, then moves up to 320 grit, then uses a plateau hone to finish it up. You want about a 45 degree angle of crosshatch. This allows for proper break in, and oil retention.
LIFTER BORE
lifter bores he likes to hone these as well for oil retention. about 400-500 grit. Same angle, 45 deg.
wash block he uses a parts washer to clean it out. then checks ring gap
RINGS
tensioning if you dont know how to de-tension the rings, just buy de-tensioned rings. Leave the TOP not detensioned, only detension the second scraper and the corrugated oil ring. Low tension rings can flutter at 7-8k rpms without holding compression, which is why you should not have a detensioned top ring.
ring clean up Rings out of the box can have rough edges and build up. Take a scotch-brite pad to clean them up around all side. You are just trying to clean up the roughness, not sand or apply lots of pressure. This removes the bits that break off the ring on start-up that score the piston.
end gap measurement Top ring should be .006"-.008", second ring .008"-.010" Put the rings in the block down just a tiny bit, use the piston to push it in and measure with feeler gauge. if too large, get file to fit, if too small, file to fit. Check ring gap at top of cylinder and about 3/4 of the way down the cylinder. Squirt a bit of WD-40 in there to avoid scratching when measuring ring gap. when the cylinder gets hot, the pistons could butt together at .002"
CONNECTING ROD AND CRANK
torque to 120 inch pounds
use micrometer and dial bore gauge to check oil clearance, which should be about .0025" to .003"
plastigauge vs dial bore and micrometer plastigauge tells you clearance in one spot, but dial bore will do that and tell you if it is out of round. Out of round rod and crank will start to gall the crank journal.
crank journal journals may come out of the factory big, so you have to make sure you polish it down to get the proper oil clearance. You can use emory cloth to polish it down with a 300-400 grit emery cloth.
crank clearance casting hump just above the journal rubs on the connecting rod. Take a dremel and knock it down.
connecting rod dont use a ball hone to clearance it, which makes oil spread to the outside edges of the rod journal. Use a stone hone for that to keep clearance even. get that cross hatch on it (we are talking stock rod)
wrist pin .001 to .0015" clearance. He runs a ball hone through this just to get the cross hatch.
CLEAN
spray down with carb cleaner, wash with parts washer, and maybe spray it with WD-40 on it to prevent flash rush. Clean everything a lot. Can use soapy water and wash, then add wd-40. If you want it cleaned right, use a sonic cleaner. You cant clean the block enough. Get it super clean.
After that, get a 25% mineral spirits, 75% ATF fluid. wipe down. Clean clean clean clean.
ASSEMBLY
put piston in with the arrow pointing down, oil dipper hole in rod points down, dipper points down.
rings go in with a ring compressor, Popsicle sticks can mess it up.
assembly oil not needed, use whatever oil you will be using to break the engine in.
use a torque wrench or you will end up like that one guy on this forum. Harbor freight click torque wrenches are CRAP, and can snap bolts. IF you are going to use one, just break it in by making it click a crap-load of times at max torque setting on a bolt that you don't care about.
TORQUE SPECS
120 inch pounds stock con rod
170 inc pounds arc billet rod
220 inch pounds cylinder head
200 inc pounds side cover
FAVORITE VIDEO 'QUOTE' "im not saying this is illegal, but it is illegal. You can get tossed out for it.... if you dont cover it up well. Dont come crying to me if you get kicked out for this, but you can cover it up"
MISC QUESTIONS THAT MATTER
Q. Can you run a piston with no or a short skirt?
A .You want it at around 3 thousandths. You need tighter clearance.
Q. Stock piston to sidewall clearance?
A. Almost all stock pistons run about .004" to .0045" wiseco and shorter have tighter clearances, usually around .003"
Q. How far out of round can the crank journal be?
A. .001"
Q. Can i get a copy of the torque spec sheet that comes in the U-Build It Engines? (what Jody was referring to throughout his video)
A. Yes, call and ask for it and we will email or fax it to you.
Q. Does the size of the oil hole in the rod matter?
A. Yes. Don't make it a lot bigger. Just deburr and make it round. Too big and it can affect the integrity of the rod.
THE END
bob58o
SuckSqueezeBangBlow
Great Work KF.
I started taking notes. I stopped at 0.006-0.008" For the top ring gap. LOL
It was the first thing he mentioned when I flipped it on.
The illegalness????
Grinding the sides of the stock connecting rod so that the casting flash (or whatever) doesn't wear away while inside the block and add lots of unwanted metal into your oil.
IIRC the Con Rod will slide back and forth on the Crank Journal and the sides of the Con Rod wear as they rub on the "lips" of the journal.
I started taking notes. I stopped at 0.006-0.008" For the top ring gap. LOL
It was the first thing he mentioned when I flipped it on.
The illegalness????
Grinding the sides of the stock connecting rod so that the casting flash (or whatever) doesn't wear away while inside the block and add lots of unwanted metal into your oil.
IIRC the Con Rod will slide back and forth on the Crank Journal and the sides of the Con Rod wear as they rub on the "lips" of the journal.
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