Thread Sealant on Head Bolts

[MIKLAV1315]

Dear Friends,

Do cylinder head bolts and engine lifting loop studs need thread sealant?

Working on D750. Installed a new cylinder head. Purchased from KUBOTA new head bolts, cylinder head gasket, exhaust manifold studs, and studs for engine lifting loops. The only hardware that any type of thread sealant on them was the exhaust manifold studs.

Respectfully,

Mike from CLE

 

[D2Cat]

No, is the answer, don't use thread sealant on head bolts.

 

[i7win7]

Think I would use never seize on exhaust bolts/studs. Recently using it on mower blade bolts. Heard stories of old-timers using milk of magnesia (magnesium) to prevent bolts from siezing

 

[Bark]

On auto engines I just use a small coating of auto oil unless they went through a water jacket, than I used anti-seize on the threads. However, if possible check the SM if you have one or check with the dealer who sold you the bolts and stuff. Let us know what you find out.

 

[Jim L.]

Light coat of engine oil on head bolt threads. The reason is that the torque settings assume the light coat of oil. If they're dry, they won't set at the correct torque.

 

[Motronic]

Light coat of engine oil on head bolt threads. The reason is that the torque settings assume the light coat of oil. If they're dry, they won't set at the correct torque.

The torque spec assumes a light coat of oil if and only if it calls for a light coat of oil. Plenty call for dry and this absolutely makes a difference.

 

[whitetiger]

Dear Friends,

Do cylinder head bolts and engine lifting loop studs need thread sealant?

Working on D750. Installed a new cylinder head. Purchased from KUBOTA new head bolts, cylinder head gasket, exhaust manifold studs, and studs for engine lifting loops. The only hardware that any type of thread sealant on them was the exhaust manifold studs.

Respectfully,

Mike from CLE
[/QUOTE
Use only engine oil if it is specified, in this case, it is specified.