helicoil recommendations

[fowens]

need to get thread on gearbox where slave cylinder bolts to be helicoiled,
gearbox is out of the car etc.

anyone know anyone that can do it in my backyard? not the kinda thing i wanna be lugging to a workshop for a helicoil..

[evoeata]

Kits usually come with a drill bit and the coils. It's easily a backyard job with a cheap powerdrill.

[S133LTR]

The kit will have an odd size drill (you wont have in a normal 1mm incriment set) a tap the actual helicoils themselves and handle to screw in the coil once you have tapped the new hole.

Stand the box up then just use your normal pistol drill (running slowly) to drill the hole out as straight as you can. Tap the holes with the tap provided then screw the helicoil in and break the tab off (instructions are in the kits).

If your NOR Odins rents the kits and sells the helicoils indivdually (kits can be pricey)

[P100_Ute]

think kits are about $50 roughly.
i bought 2 kits back in 2005 when i was building my motor.
one for a head bolt and one for the water pump. worked a treat. neither failed

[johnnyrx7]

wow head bolt! never would have thought a helicoil would take that sort of torque.

I get a guy by the name of peter whitefoot to come do our thread repairs in the workshop, he's wellpriced and a top bloke.

[fowens]

Hey Johnny you got a contact number?

[johnnyrx7]

0438068166
peter whitefoot thread repairs

[fowens]

thanks mate!

[johnnyrx7]

howd ya go lad? get hold of old whitefoot?

[fowens]

Box is being moved to workshop who deals with him to get better price. Should piss it in. Thanks again

[MaTTe]

you dont wanna use helicoils for headbolts..
they torque up, but the tension doesn't go down on the head, the helicoil binds and compresses so the tension is the helicoil locked.. they're evil things.
If you need to rethread a block you need to drill the block out big enough to put proper inserts in, there is a company in Queensland that make PROPER inserts, they used to go by the name of Kross Threads

[Lump]

they torque up, but the tension doesn't go down on the head, the helicoil binds and compresses so the tension is the helicoil locked..
this does not make any sense to me.
care to rephrase?

[MaTTe]

Originally Posted by MaTTe View Post
they torque up, but the tension doesn't go down on the head, the helicoil binds and compresses so the tension is the helicoil locked..

What I mean by this is, when you have a helicoil in the block and you start to tighten the bolt, it will feel like the bolt is tightening normally, as in screwing into the 'thread'
However once you get past a certain torque range the helicoil starts pulling upward, and due to the fact a helicoil is not solid, it will lock. Once it starts locking you will think the head is being torqued down, despite the fact that there is very little pressure going down on the head.

So to sum it up, a helicoil might be fine to 30ft/lbs, but at 60ft/lbs it still only has the head torqued down at 30ft/lbs despite what the torque wrench says and the effort you put into tightening the bolt.

To tighten a headbolt to the correct setting be it 60ft/lbs or 90ft/lbs you need to have a solid thread for the bolt to screw into.

You'd be surprised at how many race engines suffer because of the hype about helicoils. Many will blow a head gasket within the first few laps EVERY race. Then when they insert the block with a REAL insert, they wont blow a gasket all season.

We've had blocks so bad that we've had to insert every thread, and still never blown a head gasket..

bit of food for thought

[P100_Ute]

maybe i was lucky. never had any head troubles.
engine died when the dipstick got sucked into the crank.. then it was a rattly drive home. then 5g clutch dumps to see if i could kill it.
didnt work. so i ended up giving up and just pulling the motor out.

[Lump]

To tighten a headbolt to the correct setting be it 60ft/lbs or 90ft/lbs you need to have a solid thread for the bolt to screw into.


so why not tap the helicoil thread deep enough so the coil has something to bottom out on, because that will fix your issue.

[johnnyrx7]

What I mean by this is, when you have a helicoil in the block and you start to tighten the bolt, it will feel like the bolt is tightening normally, as in screwing into the 'thread'
However once you get past a certain torque range the helicoil starts pulling upward, and due to the fact a helicoil is not solid, it will lock. Once it starts locking you will think the head is being torqued down, despite the fact that there is very little pressure going down on the head.

So to sum it up, a helicoil might be fine to 30ft/lbs, but at 60ft/lbs it still only has the head torqued down at 30ft/lbs despite what the torque wrench says and the effort you put into tightening the bolt.

To tighten a headbolt to the correct setting be it 60ft/lbs or 90ft/lbs you need to have a solid thread for the bolt to screw into.

You'd be surprised at how many race engines suffer because of the hype about helicoils. Many will blow a head gasket within the first few laps EVERY race. Then when they insert the block with a REAL insert, they wont blow a gasket all season.

We've had blocks so bad that we've had to insert every thread, and still never blown a head gasket..

bit of food for thought

had this happen on a outboard headbolt i was trying to repair quickly (next day trip to exmouth) helicoil's in my opinion are a light duty repair.

sleeved inserts are defo the go.

[Lump]

^sounds like you didnt install it properly.
problem with some other types of inserts is you have to drill a much larger hole - which may weaken the surrounding metal - especially in a engine block that has water jackets etc..
helicoils are not light duty if installed correctly with the correct amount of thread engagement - ~2 times the thread diameter.
infact they will be stronger than the thread that was drilled out.

[johnnyrx7]

^sounds like you didnt install it properly.
problem with some other types of inserts is you have to drill a much larger hole - which may weaken the surrounding metal - especially in a engine block that has water jackets etc..
helicoils are not light duty if installed correctly with the correct amount of thread engagement - ~2 times the thread diameter.
infact they will be stronger than the thread that was drilled out.


I dont think the helicoils ive used have ever had suffecient thread height too enable twice the diameter? might be wrong though, havent used them in a while.

[Endless]

To save starting a new thread... anyone know who else is recommended for thread repairs? Peter Whitefoot not available until 29th and i need some work done asap.

[Lump]

any machine shop? what do you need done?

[Endless]

Has to be a mobile service.. 10mm bolt has snapped off into a not easily removable part of the motor. Easy out has failed.. Happy to pay a pro to sort it after much fucking around today in the heat.

[F6Hoon]

90 degree drill fit man or not, if so start drilling bolt out to just smaller than bolt size then run tap up it