Stripped belt tensioner bolt hole

kazbek1 · 11-22-2019, 02:36 PM

Just took out my old belt tensioner and am attempting to install the new one. I don't know if I was initially going at it on an angle but the bolt just doesn't want to catch and I think I stripped the first 2 or 3 threads. Any advice on how I can fix this? Any one know the size/measurements of the hole and threads in case I need to drill it out and install new threads (Helicoil)? This is the first time I'm dealing with bolt holes and threads and all that lovely stuff so I'm pretty lost. The bolt has 10.9 printed on the head. Any help would be great. Thanks in advance!

Antetokounmpo · 11-22-2019, 03:21 PM

First step is to chase the threads with a tap. 10.9 is the bolt class, nothing to do with size. Measure the major diameter and pitch then purchase a tap.

woodex m.e. · 11-22-2019, 10:30 PM

If the hole is totally boned, drill, tap and put a helicoil in it.

kazbek1 · 11-23-2019, 08:03 AM

Thanks guys! After nearly 3 hours of trying to get the bolt to line up straight and stop moving around, I managed to get it in. I imagine I stripped a few more threads as it wasn't easy screwing it back in but I got the job done. Glad I learned something from you guys though. Cheers!

11-22-2019, 02:36 PM	#1
kazbek1 Second Lieutenant 74 Rep 256 Posts Drives: 2007 335i Join Date: Mar 2013 Location: Merritt Island, FL iTrader: (0)	Stripped belt tensioner bolt hole Just took out my old belt tensioner and am attempting to install the new one. I don't know if I was initially going at it on an angle but the bolt just doesn't want to catch and I think I stripped the first 2 or 3 threads. Any advice on how I can fix this? Any one know the size/measurements of the hole and threads in case I need to drill it out and install new threads (Helicoil)? This is the first time I'm dealing with bolt holes and threads and all that lovely stuff so I'm pretty lost. The bolt has 10.9 printed on the head. Any help would be great. Thanks in advance!
	Appreciate 0 Tweet Quote

11-22-2019, 03:21 PM	#2
Antetokounmpo Brigadier General 1560 Rep 3,475 Posts Drives: E90 6MT FBO; '18 F150 Platinum Join Date: Jul 2013 Location: WI iTrader: (3) Garage List 2018 Ford F-150 Pla ... [0.00] 2008 BMW 335xi [0.00]	First step is to chase the threads with a tap. 10.9 is the bolt class, nothing to do with size. Measure the major diameter and pitch then purchase a tap. __________________ 2008 335xi 6MT \| VRSF Catless DP \| VRSF 7" FMIC \| VRSF CP \| TIAL BOV \| DCI \| MHD 2+ BC Racing BR \| Stoptech 600 \| Firehawk Indy 500 255 Square \| Atric Altimax 225 Sq. 2018 F-150 Platinum 701A \| FX4 \| 3.5 EcoBeast
	Appreciate 3 mweisdorfer1933.50 feuer4286.50 Quote

11-22-2019, 10:30 PM	#3
woodex m.e. Private First Class 70 Rep 113 Posts Drives: 2007 335xi 6MT Join Date: Aug 2018 Location: Maine iTrader: (0)	If the hole is totally boned, drill, tap and put a helicoil in it.
	Appreciate 0 Quote

11-23-2019, 08:03 AM	#4
kazbek1 Second Lieutenant 74 Rep 256 Posts Drives: 2007 335i Join Date: Mar 2013 Location: Merritt Island, FL iTrader: (0)	Thanks guys! After nearly 3 hours of trying to get the bolt to line up straight and stop moving around, I managed to get it in. I imagine I stripped a few more threads as it wasn't easy screwing it back in but I got the job done. Glad I learned something from you guys though. Cheers!
	Appreciate 0 Quote