Rusty_S85 Posted August 19, 2022 Share Posted August 19, 2022 She saved the pulley! I've tried 3 different pulleys and none of them were going to work. I was looking a the engine with a flashlight and spotted the pulley down in the motor mount. This space is like a belly button for the straight six. All kinds of junk in there. Anyway, in her infinite grace my dearest trucky held on to the pulley. It looks to be a 17mm inner diameter which is common but the outer diameter is 50 mm and is not very common. Since the pulley runs on the back of the belt, any thoughts on using a more common pulley without side flanges or even using a serpentine pulley? https://forum.garysgaragemahal.com/file/n123600/IMG_9636.jpg Clean the bearing up and look on the rubber seal on both sides there should be a part number on the seal that you can cross over to a modern bearing. Link to comment Share on other sites More sharing options...
tanman Posted August 19, 2022 Author Share Posted August 19, 2022 The bearing is a Fafnir 203P Fafnir is now Timken but it appears to be a 17x40x12 bearing Couldn't find a pulley though. Still wondering if a 50-55 mm flat or serpentine idler pulley would work. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 19, 2022 Share Posted August 19, 2022 The bearing is a Fafnir 203P Fafnir is now Timken but it appears to be a 17x40x12 bearing Couldn't find a pulley though. Still wondering if a 50-55 mm flat or serpentine idler pulley would work. Can't you press the old bearing out and a new one in? Link to comment Share on other sites More sharing options...
tanman Posted August 19, 2022 Author Share Posted August 19, 2022 Gary, I will have to figure that out. I think this was a hardware failure. You can see in the original picture the assembly of the pulley does not look good. The threaded hole in the bracket appears to be a 7/16 or M11 I think I need to find a bushing or reducer to get the 17mm inner diameter of the bearing to ride on a cap bolt that fits into the bracket. Â Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 19, 2022 Share Posted August 19, 2022 Gary, I will have to figure that out. I think this was a hardware failure. You can see in the original picture the assembly of the pulley does not look good. The threaded hole in the bracket appears to be a 7/16 or M11 I think I need to find a bushing or reducer to get the 17mm inner diameter of the bearing to ride on a cap bolt that fits into the bracket. Yes, if the bolt is smaller than the ID of the bearing you'll have a problem. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted August 19, 2022 Share Posted August 19, 2022 The bearing is a Fafnir 203P Fafnir is now Timken but it appears to be a 17x40x12 bearing Couldn't find a pulley though. Still wondering if a 50-55 mm flat or serpentine idler pulley would work. Thats the bearing you need a 203P. The brand doesnt matter much as Ive found automotive bearings like this uses some form of standardized part number that will cross over brands. What you will need to do is press the bearing out to do this you will need to check both sides of the pulley as some pulleys will have a lip you press the bearing up against and some it doesn't matter. Once you find this out you can use a vice and a large socket on one side and a smaller socket that fits the race on the other side to press the bearing out. It is a press fit but you do not need a hydraulic press to remove it. Once you get it removed, I recommend double checking the OD, I bet you the OD of the bearing will be 40 and your 50mm measurement was measuring to the taper to help start the bearing. I do how ever recommend Timken brand bearings over other brands and their part number is 203P as well. I personally would just replace the bearing vs trying to find another pulley. Not only would it be cheaper but it will save you the time trying to find a pulley that is the right dimensions. Link to comment Share on other sites More sharing options...
mat in tn Posted August 20, 2022 Share Posted August 20, 2022 The bearing is a Fafnir 203P Fafnir is now Timken but it appears to be a 17x40x12 bearing Couldn't find a pulley though. Still wondering if a 50-55 mm flat or serpentine idler pulley would work. Thats the bearing you need a 203P. The brand doesnt matter much as Ive found automotive bearings like this uses some form of standardized part number that will cross over brands. What you will need to do is press the bearing out to do this you will need to check both sides of the pulley as some pulleys will have a lip you press the bearing up against and some it doesn't matter. Once you find this out you can use a vice and a large socket on one side and a smaller socket that fits the race on the other side to press the bearing out. It is a press fit but you do not need a hydraulic press to remove it. Once you get it removed, I recommend double checking the OD, I bet you the OD of the bearing will be 40 and your 50mm measurement was measuring to the taper to help start the bearing. I do how ever recommend Timken brand bearings over other brands and their part number is 203P as well. I personally would just replace the bearing vs trying to find another pulley. Not only would it be cheaper but it will save you the time trying to find a pulley that is the right dimensions. well, I got a good look at the assembly that I have in the shop. it is the exact same as you have. it seems as if yours may have come unbolted. have you found the bolt yet? I am intending to offer for sale the entire dealer ac system as it was from the beginning if someone wants to put it to use or use the parts. "Parts" is probably the best use. Link to comment Share on other sites More sharing options...
tanman Posted August 20, 2022 Author Share Posted August 20, 2022 I found a dayco pulley that may work. Again I think the hardware failed as the pulley appears to be fine. I will need to find a reducer to step the size down to hold an 11mm bolt. Link to comment Share on other sites More sharing options...
tanman Posted August 20, 2022 Author Share Posted August 20, 2022 well, I got a good look at the assembly that I have in the shop. it is the exact same as you have. it seems as if yours may have come unbolted. have you found the bolt yet? I am intending to offer for sale the entire dealer ac system as it was from the beginning if someone wants to put it to use or use the parts. "Parts" is probably the best use. I would be interested in the idler pulley assembly pulley. Does your setup have the bolt adjustable tension pulley near the power steering pump? Link to comment Share on other sites More sharing options...
Rusty_S85 Posted August 20, 2022 Share Posted August 20, 2022 well, I got a good look at the assembly that I have in the shop. it is the exact same as you have. it seems as if yours may have come unbolted. have you found the bolt yet? I am intending to offer for sale the entire dealer ac system as it was from the beginning if someone wants to put it to use or use the parts. "Parts" is probably the best use. Yeah hes going to need the special bolt for that unless he can machine a spacer to mimic the bolt with the shoulder to properly fit the ID of the bearing. Link to comment Share on other sites More sharing options...
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