Planet Minis

mexicanyella · 11-18-2008, 02:13 PM

I'm not at this point yet, but I've seen that stroker kits sometimes mention using a thinnner driveshaft to the pump for clearance. How do you get that out? Hold the sprocket still and screw the shaft out, or is it a press fit, or what?

1998 Honda Z125R · 11-18-2008, 02:29 PM

It is threaded so all youll have to do is spin it off: Take the clutch cover off and remove the oil pump, break the oil pump shaft loose with a regular screwdriver while the timing chain is still on and holds it, you can grab the flywheel to keep the cam chain and sprocket from moving. Just break the shaft loose, dont completely remove it. Now disassemble the top end. Just make sure there is slack in the cam chain before you take the oil pump shaft all the way out.

mexicanyella · 11-18-2008, 02:49 PM

Thanks! That sounds pretty simple. I was looking at an already disassembled engine, scratching my head and wondering how to hold the parts still or if it was pressed in or something.

arlindsay1992 · 11-18-2008, 04:52 PM

If you have a newer motor, the shaft is different and required splitting the cases so you can get a pair of pliers on the flat part. The older ones are shaped like a flat screw and can be removed with a flat screwdriver. The newer ones are shaped like a flat screwdriver and thus are impossible to remove without splitting the cases. The shaft in your motor either fits into this oil pump (newer motors), or looks exactly like the drive for this pump (older motors). This pump would fit on the shaft that comes on newer engines. I hope I didn't confuse you.

mexicanyella · 11-18-2008, 08:40 PM

While confusing me is sometimes easily done, I think I followed that, and thanks for the info. It's good you pointed that out, too; I'll have to see if the China motor I was going to use the top end and oil pump from is the newer style to go along with its 12V crank taper. I want to swap it onto a 6V bottom.

mexicanyella · 11-19-2008, 01:50 PM

After reading last night's posts on this subject I was looking at the oil pump drive sprocket and shaft on the China 110 engine, turning it with my finger, and saw that there's a substantial wobble in the pump drive sprocket as it turns. The shaft seems to turn smoothly with little resistance but I can't believe that wobble didnt' derail the timing chain at running rpm. Creepy. Ever seen this?

arlindsay1992 · 11-19-2008, 02:17 PM

I've never seen/heard anything like that. The oil pump shaft always has spun freely but without play. A forward and back movement along the axis of the pump shaft is normal but that's it. The only movement should be spinning/sliding on that one axis.

mexicanyella · 11-19-2008, 02:49 PM

Quote:

Originally Posted by arlindsay1992

I've never seen/heard anything like that. The oil pump shaft always has spun freely but without play. A forward and back movement along the axis of the pump shaft is normal but that's it. The only movement should be spinning/sliding on that one axis.

Yeah, the shaft itself turned with no runout I could see anywhere along its length, but the sprocket wobbled out of true. It was like the end of the shaft that threads into the sprocket was bent, or the hole through the sprocket wasn't lined up axially or something. Weird. Chinese manufacturing issue? No sign of other damage in there.

arlindsay1992 · 11-19-2008, 04:15 PM

I was trying to save a couple bucks on a motor once and bought a Chinese oil pump drive sprocket. Turns out it the threaded hole was not exactly in the center. It was only off by about 0.25mm because the total up and down was about 0.5mm. But it managed to ruin itself and my cam sprocket. So I needed to spend about $20 on an OEM cam sprocket and an OEM oil pump sprocket because I saved $3 on the Chinese oil pump sprocket.

11-18-2008, 02:13 PM	#1 (permalink)
mexicanyella El rey de los puntos Join Date: Aug 2008 Location: Troy, MO Posts: 974	How do you remove the oil pump drive shaft and its sprocket? I'm not at this point yet, but I've seen that stroker kits sometimes mention using a thinnner driveshaft to the pump for clearance. How do you get that out? Hold the sprocket still and screw the shaft out, or is it a press fit, or what?

11-18-2008, 02:29 PM	#2 (permalink)
1998 Honda Z125R 1st Gear Member Join Date: Mar 2007 Location: Florida Posts: 243	Re: How do you remove the oil pump drive shaft and its sprocket? It is threaded so all youll have to do is spin it off: Take the clutch cover off and remove the oil pump, break the oil pump shaft loose with a regular screwdriver while the timing chain is still on and holds it, you can grab the flywheel to keep the cam chain and sprocket from moving. Just break the shaft loose, dont completely remove it. Now disassemble the top end. Just make sure there is slack in the cam chain before you take the oil pump shaft all the way out.

11-18-2008, 02:49 PM	#3 (permalink)
mexicanyella El rey de los puntos Join Date: Aug 2008 Location: Troy, MO Posts: 974	Re: How do you remove the oil pump drive shaft and its sprocket? Thanks! That sounds pretty simple. I was looking at an already disassembled engine, scratching my head and wondering how to hold the parts still or if it was pressed in or something.

11-18-2008, 04:52 PM	#4 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: How do you remove the oil pump drive shaft and its sprocket? If you have a newer motor, the shaft is different and required splitting the cases so you can get a pair of pliers on the flat part. The older ones are shaped like a flat screw and can be removed with a flat screwdriver. The newer ones are shaped like a flat screwdriver and thus are impossible to remove without splitting the cases. The shaft in your motor either fits into this oil pump (newer motors), or looks exactly like the drive for this pump (older motors). This pump would fit on the shaft that comes on newer engines. I hope I didn't confuse you.

11-18-2008, 08:40 PM	#5 (permalink)
mexicanyella El rey de los puntos Join Date: Aug 2008 Location: Troy, MO Posts: 974	Re: How do you remove the oil pump drive shaft and its sprocket? While confusing me is sometimes easily done, I think I followed that, and thanks for the info. It's good you pointed that out, too; I'll have to see if the China motor I was going to use the top end and oil pump from is the newer style to go along with its 12V crank taper. I want to swap it onto a 6V bottom.

11-19-2008, 01:50 PM	#6 (permalink)
mexicanyella El rey de los puntos Join Date: Aug 2008 Location: Troy, MO Posts: 974	Re: How do you remove the oil pump drive shaft and its sprocket? After reading last night's posts on this subject I was looking at the oil pump drive sprocket and shaft on the China 110 engine, turning it with my finger, and saw that there's a substantial wobble in the pump drive sprocket as it turns. The shaft seems to turn smoothly with little resistance but I can't believe that wobble didnt' derail the timing chain at running rpm. Creepy. Ever seen this?

11-19-2008, 02:17 PM	#7 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: How do you remove the oil pump drive shaft and its sprocket? I've never seen/heard anything like that. The oil pump shaft always has spun freely but without play. A forward and back movement along the axis of the pump shaft is normal but that's it. The only movement should be spinning/sliding on that one axis.

11-19-2008, 04:15 PM	#9 (permalink)
arlindsay1992 "High Speed Record Guy" Join Date: Mar 2006 Location: Northern Virginia Posts: 4,369	Re: How do you remove the oil pump drive shaft and its sprocket? I was trying to save a couple bucks on a motor once and bought a Chinese oil pump drive sprocket. Turns out it the threaded hole was not exactly in the center. It was only off by about 0.25mm because the total up and down was about 0.5mm. But it managed to ruin itself and my cam sprocket. So I needed to spend about $20 on an OEM cam sprocket and an OEM oil pump sprocket because I saved $3 on the Chinese oil pump sprocket. Attached Thumbnails

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)