stripped thread help.

[steve_k]

evening folks looking for a bit of advise.

went to do a mates cambelt on his m20, when i went to remove the upper timing cover i noticed that on the bolts which holds both the upper cover & lifting eye had be helicoiled before & not very well as the coil was still on the bolt when i took it out.

thing is, what the best option to proceed with? retap it & use another helicoil?
or drill it out & retap it to M8 size?

got all the bits here to do either so just wondering which route folk think is best?

[steve_k]

anyone?

[Scotty200]

Personally for me if there is enough meat around the hole I would go the drill and retap less chance of the threads pulling out again at a later date

[steve_k]

Personally for me if there is enough meat around the hole I would go the drill and retap less chance of the threads pulling out again at a later date

thats what i was thinking, will have a god look today & see if there is enough there to drill it out & retap it.

[Satan]

As above, better a proper job then a bodge.

[steve_k]

well it's all done now, used the correct tap & recut it to M8 size, also did the other side while i was there so they both match up.

[martauto]

well it's all done now, used the correct tap & recut it to M8 size, also did the other side while i was there so they both match up.

Just seen this Steve and thats exactly what I would have done and full marks for doing both sides as well mate !!!

Mart, toolmaker by trade.

[paultv]

I have the same issue, looking at the engine from the front its the left hand bolt that runs thru' the lifting eye and into the head? its a bolt with a long shank and end thread if I remember - so M8 is the next tap up? I need to do mine, is there any issue with swarf from drilling, internally I mean?

Paul

[martauto]

Dont know exactly but run the drill very slow and put grease on the bit to try and hold onto the cuttings making sure you clear the bit often.

Mart.

[steve_k]

@mart, cheers dude, had a big tub of grease so dipped the bit & tap in it before going very slowly with the drill.

@paultv, thats the one i had to do, M8 is the next step up & a lot stronger when you consider that the engine hangs off there on a hoist.

[Satan]

Tallow for threading,