How to repair damaged threads on a Sachs Dolmar Crankcase
In this video, we show you how to re thread the holes located in a Disc Cutter Crankcase that attaches the cylinder on a Sachs Dolmar using a M5 x 0.8mm Helicoil Kit.
Health & Safety Warning - Please ensure that you have safely prepared the machine and workspace. If you are unsure about any aspect of the task please seek professional advice.
Today we're going to show you an easy way to re-thread the holes located in a Disc Cutter Crankcase that attaches the cylinder on a Sachs Dolmar using a M5 X 0.8mm Helicoil Kit. This technique can be used for many different parts and machines to repair damaged threads. Before starting, you will still need to determine the size of the helicoil needed to re-thread. In this video we will be using the M5 x 0.8mm Helicoil Kit. As a top tip, a simple and cost effective way to know how far to drill out a damaged thread is to measure the depth of the hole and mark this on the drill. Holding the part in place using a vice, drill out the hole using a power drill to the markings, identifying how far to drill to. Now using the tap from the helicoil kit, place this in a ratchet to easily re-thread the hole. Make sure that the tap is aligned correctly. Then slowly cut the new threads into the crankcase. Turn until you have re-threaded the hole and then release by unscrewing the ratchet. Now get the installation tool and adjust so you know the measurement of the hole depth for the new insert. When you know the size, attach the spring on the end of the tool making sure the tang is in the slot. Now place this in the hole, twisting the new helicoil until it is secure. This should be half a turn below the surface. Do not twist against the direction of the thread, as this could damage the spring. Then to remove the tang at the end of the spring, gently tap this with the break tool provided. That's how you re-thread the holes located in a Disc Cutter Crankcase on a Sachs Dolmar using a M5 x 0.8mm Helicoil Kit.
Parts and tools included in the thread repair how-to video.
- 5mm Helicoil Thread Repair Kit - 902 1537