Welcome to the all new Geo Metro Forum. We hope you enjoy your visit.You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are features you can't use and images you can't see. Registration is simple, fast, and completely free. If you're already a member please log in to your account to access all of our features: Join our community! |
| crank pully | |
|---|---|
| Tweet Topic Started: Jul 20 2012, 03:56 PM (780 Views) | |
| Rustyss73 | Jul 20 2012, 03:56 PM Post #1 |
|
Member
![]() ![]() ![]() ![]() ![]()
|
whats the difference between a 4 bolt and 5 bolt pullys and cranks.. can you swap them and are interchangeable asuming you change the top pully..? |
![]() |
|
| t3ragtop | Jul 20 2012, 04:17 PM Post #2 |
|
Turbo3 and Twincam Tweaker
![]()
|
it's the crankshaft timing belt gear that has the holes in it to mount the accessory drive pulley. depending on the year and engine configuration you can r&r the timing gear with a 4 or 5 bolt hole type. the trick is matching the timing belt and cam gear to match. generally, the 4 hole gears have drive teeth for the square tooth timing belt while the 5 hole gears fit the rounded tooth timing belt. timing belt width can vary as well which dictates the timing gear combination you must use. the older style 4 bolt accessory drive pulleys are a 3 rib type belt, the later style 5 bolt accessory drive pulleys are a 4 rib type belt so you have to be careful about your selection of complimenting pulleys. i have run into belt alignment issues while trying to convert from a 3 rib belt to a 4 rib belt on some g10 engines. further complicating things, some alternators have 3 rib drive pulleys, some have 4 rib drive pulleys and sometimes they don't always accept an alternator drive pulley changeover. some alternators have a small diameter shaft while others have a larger diameter shaft. and i still have to make a trip to the wrecking yard to check if there is a difference between g10 and g13 bottom alternator mounting bracket dimensions. i've swapped a few engines around from square tooth timing belts to the wider round tooth timing belts and 3 rib accessory belts to 4 rib belts, more by trial and error and luck than by intelligent design.
|
![]() |
|
| 1 user reading this topic (1 Guest and 0 Anonymous) | |
| « Previous Topic · Engine Tech & Diagnostics · Next Topic » |


Welcome to the all new Geo Metro Forum. We hope you enjoy your visit.


![]](http://z3.ifrm.com/static/1/pip_r.png)




9:42 AM Jul 11