moly lube or not to lube

[errol]

Hi gents,I've read the article about the torque spec.on ARP bolts/studs,someone mentioned not to use the moly lube,(not on this site).having never experience building an eng.using ARP's I'm seeking ur opinions,do i lube the studs before screwing them into the block & on the threads for clamping head,how was ur's done.Thx Errol

[A.J.]

You do not lube the threads that go into the block. Those are installed finger tight after you clean the threads in the block. You lube the portion of the stud that the nuts spin onto. I also lube the washers and the bottom of the nuts to help assure friction-free assembly.

A.J.

[zin]

ALL traditional (FSM) torque specs assume the use of 30W motor oil. ARP's specs generally will give specs assuming the use of their moly lube. Sometimes they'll list both, in which case you'd notice that the moly spec is significantly lower due to the better lubricity of the moly. Either way, what we are attempting to do is obtain a specific amount of stretch on the fastener, which is why you may have seen rod bolt stretch gauges, pretty much the only fastener in an engine that this technique can be used on, but an important one nonetheless.

So, in short always use some kind of lube, whether or not you use their moly is your choice, just be sure to use the right torque spec for the lube you are using.

Mike

[errol]

Thx AJ ur response is appreciated,putting the eng.together with so much info coming at u,one tends to second guess ones self .

---------- Post added at 07:52 AM ---------- Previous post was at 07:48 AM ----------

Thx Mike,need all the knowedge i can get for this project,don't want to screw it up.Errol

[contraption22]

Actually I beleive that ARP came out with a new lube that gives more consistent torque-to-stretch. It was on HoresepowerTV recently.

http://arp-bolts.com/pages/arpultratorque.shtml

[errol]

Thx Mike i'll chk it out.Regards.Errol

[Directconnection]

Actually I beleive that ARP came out with a new lube that gives more consistent torque-to-stretch. It was on HoresepowerTV recently.

http://arp-bolts.com/pages/arpultratorque.shtml

Yes, it comes in a blue packet now vs. the thinner slipperier stuff on the old white packet.

Their now formulated moly is *grainy* compared to the old, and reminds me of valve lapping compound... hehehe

The reason behind the switch is because the older moly formula never stayed consistant, and you really needed to mix up up good. Guys in the shop tell me that if you break down your setup with the moly, you need to re-apply it again for re-torqueing.... I've never seen an issue with that, but something to be aware of.

Our shop uses CDM #3 which is almost like a grease of sorts. A LOT of the pro shops use this vs. moly.... and Crower recommends a certain # anti-seize on their rod bolts.

Whether you use 30wt oil, moly, or CMD.... use the torque suggested for THAT lube only. Especially if machine work was done with rods, mainline, etc... as going from 30wt to a moly lube WILL overstretch your bolts and/or change your housing bore quite a bit.

Lube the threads, and both sides of the washers, and the nuts, too.... Just doing the threads alone makes it under-torque with an effect of under torque of like 10ftlbs or more.

[errol]

Thx Steve,I think I'll try to get the new lube from moly,wonder if there's a outlet in Canada!?