Loctite

[cat007]

Howdy all

I'm going to loctite some of my wastegates internal bolts/nuts and also thinking about doing manifold to head ones as well. Problem is I picked up Loctite 262 Super Stud Lock instead of 272 High Temperature High Strength.

The high temp stuff can handle up to 200C where as the 262 can only handle 150C

Both of these temps are lower than what I imagine the bolts/nuts would see

Is this going to cause a problem?

[Bazda]

loctite manifold and head!!!
you must be crazy.

Over time those bolts are the hardest ones to get out.

loctite the internal screws inside the gate, but not the manifolds bolts.

[cat007]

My manifold to head nuts always come loose. I've bought new bits but haven't got new studs. Might get new ones when I rip the engine out.


Oh and there's only 1 nut inside the waste gate which holds a sandwich plate onto the shaft and therefore the diaphram. There is 4 bolts around the outside the gold the top half of the waste gate onto the bottom half. Is that the ones you mean?

[sergei]

Don't use locktite on manifold nuts - pointless exercise.
You can locktite head site of the studs, but use proper castle/exhaust nuts, they are not expensive (I also use special wurth washers).

[cat007]

Don't use locktite on manifold nuts - pointless exercise.
You can locktite head site of the studs, but use proper castle/exhaust nuts, they are not expensive (I also use special wurth washers).

Why is it pointless? Because the loctite will just get too hot and fail?

The studs are in the head good and proper (I've tried removing them but couldn't get them to budge

I'm using new OEM toyota nuts at a million $ a piece IIRC

[Bazda]

Use the new nurlock washers. They have fine serrations and are VERY good IMO.

[Crampy]

Use locking fasteners or lock wire them up.
That'll stop them from undoing, but you can cut the lock wire in order to remove them when required.

[Bazda]

Get these washers, they are nicely priced and they seem to work really well.

http://www.nord-lock.com/

[cat007]

Get these washers, they are nicely priced and they seem to work really well.

http://www.nord-lock.com/

Hmm I'll look into them. Are they an off the shelf item in Auckland somewhere? Or will they need to be shipped up from CHCH?

[mjrstar]

all my exhaust componentry goes together with anti seize and good old spring washers..... works for me.

[Bazda]

Get these washers, they are nicely priced and they seem to work really well.

http://www.nord-lock.com/

Hmm I'll look into them. Are they an off the shelf item in Auckland somewhere? Or will they need to be shipped up from CHCH?

just any engineering shop

[sergei]

With spring washers, better get right ones as the certain steel looses springiness under high temp.

Stay away from chinese stuff, never seen chinese thread without huge tolerances.

Those nord-lock washers are awesome.
if you are using toyota nuts (right ones) then just use little bit of anti-sieze and those washers. The locktite is some form of plastic (epoxy or urethane based) which will fail under temperature.
Usually the case is with turbos the nuts are getting undone by themselves and with NA they are getting rusted shut.

[Adoom]

Pfft. EVERYTHING I put on the bolts/nuts/studs that touch my cast turbo manifold gets incinerated. Copper grease, loctite, normal grease, loom wires/plugs, dropped duct tape,....hell, even the nickel coating burns off the small bolts that hold my heat shield on. It gets FNCKIN HOT!!!
Use some kind of mechanical locking system, like them washers mentioned earlier. Or the locking wire, might be real fiddly to wire it up down there though.

[fivebob]

The locktite is some form of plastic (epoxy or urethane based)

Actually it's Meth-Acrylate based (same as superglue)

which will fail under temperature.

272 is good till about 250°C after which it will loosen when hot but provided it doesn't overheat (and it would on an exhaust) then it will still work when it cools down.

Recommended method for lossening loctited bolts is to heat them, which should give you some idea of it's suitability for exhaust system i.e. it isn't suitable.

There's no reason to use any loctite compound, except Anti-Sieze on an exhaust system, proper lock washers are the best solution.

[RS13]

Use locking fasteners or lock wire them up.
That'll stop them from undoing, but you can cut the lock wire in order to remove them when required.

This has my vote, we do a LOT of lockwiring around aircraft, particularly around the hot section of the turbines, and its' very effective.

[matt dunn]

I had a lot of problems with nuts and bolts etc coming loose all the time.


In the end this is what I have now and seems to be the way I got it too all stay together,
and it has now. Used to have to tighten the turbo and manifold studs after every session, so 5 times in a race weekend.
Now I dont even check them till the week after the event when we go over the car.



I use genuine toyota manifold studs in the head with helicoils,
Toyota 4AGE 20V head stud washers as washers, cause they are large and thick, and good quality,
and Toyota manifold nuts that are double the width of a std nut,
dont remember the part number, but have a packet with it on.
No liquids, sealers, or locking system at all except being done up tight.
and no gaskets on the turbo or wastegate either
as could not get them to last more than a session either.


I also credit 1/2 the problem and solution to the fact it was all new.
I believe that the problem may have been that the new manifold expanded and contracted
so much when it was new, but has settled now that has been heat cycled so many times,
but no proof on that either way

[Py7h0n]

The Bolt Shop on Archers road (next to Pool Doctor) has Nord Lock washers.

I'd also recommend them!

[postfach]

I'm probably a bit late, but I use Nord-Lock washers and stainless nuts. The washers will stop the nuts from coming loose when you don't want them to, and since the nuts are stainless, they won't really sieze onto the studs so much.

[cat007]

I'm probably a bit late, but I use Nord-Lock washers and stainless nuts. The washers will stop the nuts from coming loose when you don't want them to, and since the nuts are stainless, they won't really sieze onto the studs so much.

Cheers. I might use them in the future.

I haven't put my manifold on yet - was waiting on gaskets and a few other things to arrive and get my manifold repaired and refaced - but I have everything in my possession now (thanks Toyota NZ for having 2 our of the 3 piece kit......) so will be installing manifold and turbo tonight. I'll use loctite as haven't had a chance to get to a bolt/washer shop and won't have time on saturday probably. It'll probably do nothing - so I'll have to replace the gaskets all over again after the 1st, or they'll be fine and I wont need to