which fixings HAVE to be replaced?

[wibble_puppy]

hey guys,

so the engine is out of the van and I'm playing happily unbolting various bits from it and cleaning them up (eg water pump, thermostat housing, timing mechanism etc).

I'm keen to retain all the original bits I can, down to the washers if possible! but I am hazily aware that there must be some bits which are placed under strain, torque or other pressure and which it would be a sensible idea to replace. I'm thinking maybe head nuts and studs, for instance.

Can anyone tell me whether this is right, and if so which fixings I should be replacing rather than restoring?

(I'm not doing anything to the main block of the engine but 3 of the head nuts do have to come off as they need longer studs.) (edited to add: the plan is for each to be removed one at a time and then replaced and retorqued before removing the next)

Grateful for all advice!

juliet xx

[bigginger]

My inclination would be to replace all the studs, certainly. I've had a couple now which have sheared at under spec torque. I am, however, the unluckiest mechanic alive - or is it just the sheds I buy?

[Packedup]

hey guys,



(I'm not doing anything to the main block of the engine but 3 of the head nuts do have to come off as they need longer studs.) (edited to add: the plan is for each to be removed one at a time and then replaced and retorqued before removing the next)

Just take the head off! Then you can check the bores, clean the combustion chambers, regrind the valves if you really want... And do all the studs at the same time using a remover (a rough surfaced cam wheel type one is handy for that) rather than the 2 nut and hope method

All I can think of other than head studs (which I admit I only replaced when they break, and usually withones off another engine!) is the manifold nuts - Brass seems good for these, and they shouldn't be tightened too much so you shouldn't strip the threads. Might be worth replacing the manifold studs if they're looking at all rusty.

In fact, I'd say any studs that look rusty/ weakened should be replaced (thermostat housing ones often seem to go), but any that look nice and solid with good threads are OK to keep. Most are more general service issues than critical running ones - Stat housing, manifold etc are merely annoying when they break trying to change gaskets or stats, whereas head ones are less than fun if for any reason one gives up under load...

[bmcecosse]

Why is this up twice ?

[Welung666]

I was just thinking that BMC!

[bigginger]

Dunno, but my "merge posts" function isn't working. Anybody?

[wibble_puppy]

i've only just seen this second one doppelganger gremlins