Recommendations for which Helicoil kit to buy

[Robmsharp]

The number of iffy threads on my TV8 engine is increasing so I think its time to start thinking about a Helicoil/Timesert kit, can anyone recommend a good quality kit suitable for use by an enthusiatic DIY'er?

[jbuckl]

buy them individually.
5/16 unc is most common. inlet manifold to head; coil to manifold , thermostat to manifold , small bolts x2 pas bracket to head etc.
5/16 unf for front cover to sump
3/8 unc for exhaust manifold to head & carb pedestal stud & large bolt pas bracket to head

Last few kits I had were from :-

http://stores.ebay.co.uk/Rally-Design-Ltd?_trksid=p2047675.l2563

if you just need the inserts, try these:-

http://stores.ebay.co.uk/Chronos-Engineering-Supplies?_trksid=p2047675.l2563

Its possible to sucessfully cut down a helicoil length using a dremel or similar.
1.5d is the most common length.

[Bandit1200]

I bought a kit called Recoil. Part No 33058 off E-bay. It is a 5/16 UNC size and I rethreaded all the inlet manifold threads in the heads.
If it's your first time, as it was mine, be careful not to drill too deep for obvious reasons.
Initially, the first few coils I inserted would not accept the new bolts I had bought and realised that I was inserting the coil in the newly tapped threads too far. This caused the coils to close up.
After careful determined effort all the threads worked well and I have watertight inlet manifold.

Best wishes
Steve

[Tdm]

I think most good hardware stores, or motor factors sell various size helicoil kits.
I got mine from a specialist "Bearings" motor factors on an industrial estate in Llandudno Junction.

By the way I have had to helicoil several Inlet Manifold bolt holes, a couple of Spark Plug holes, and Power Sterring Bracket holes to-date.

[Robmsharp]

Thanks for all the advice, in thinking about the practicalities of doing the job a couple of questions spring to mind;
1. Do the Helicoils hold themselves in place or do they need a thread locking compound applied?
2. How best is it to drill a hole 'square' to the damaged thread to be replaced?

[jbuckl]

1. just a dab of red loctite on the first 3 threads, not strictly necessary.
2. flat bottomed drill not necessary, a standard 118 degree point is ok.
also
Be sure that the full helicoil thread depth is cut, otherwise the bolt will go tight before the joint is clamped, because the helicoil will taper in following the form of the short thread repair depth.
Better to have a slightly shallow thread repair than a tight bolt that isnt clamping.
Some of my helicoil taps have been ground shorter, removing the lead to make them more of a bottoming tap.

Timeserts are better repairs than helicoils, but quite a bit more cost.

[Motorsport Micky]

1)
Yes the Helicoil "self lock" into position, when any bolt is inserted it locks them into position even tighter, to give you an idea Rolls Royce Truck engines used to helicoil their cylinder block stud holes from new to help prevent stud thread damage later in life.

2)
How best to drill the holes square is dependant upon which holes are being Helicoiled and access to the area. A small drill press used with hand pistol drills can usefully be clamped upon various areas of the engine (inlet manifold faces etc) to help with a 90 deg true angle. Otherwise a practised engineer observes the angle of drill bit (not the drill body itself) and looking through two planes " juggles the hand drill to keep as close to 90 deg in each plane.

The Recoil kits are what I use, come complete with drills and instruction how to use, cheaper than Helicoil and Timsert alternatives

Micky

[NickA]

I've a selection of the Recoil kits; found them invaluable for use on the Stag. If the thread is completely stripped I don't bother drilling it out I just tap to the correct size for the insert. Rear training arm was the first use then front timing cover, rear oil seal, head for inlet manifold bolts & exhaust manifold bolts.

I buy the replacement inserts from http://www.recoilshop.net/

[Robmsharp]

Thanks once again for all the answers and advice - I've just ordered a 5/16unc Recoil kit off Ebay.

[stag8manod]

I use Recoil kits, found them very good and thread lock isn't need. A lot of the engine threads have been done. I wouldn't use heli-coil/recoil inserts for spark plugs for the risk of it screwing through, for this use a Timesert which has a locking feature and cannot move. I had the spark plugs done professionally by a local moto-sport garage with lots of Subaru experience. All good
Cheers Ian A