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I was able to look up sequence for a 1931 Packard 42 with a 385 engine. However I was not understanding what torque specs they were giving. Anyone have that info in foot pounds?

I also read to insert bolts dry. No oil or sealer?

Thanks in advance.

The most up to date procedure is found in the 38-39 shop manual.

58-60 ft. lbs. for the torque.

They specify grease on the studs and say nothing about using dry threads. Lubricated threads allow for greater clamping force.

I would use Permatex Number 1 on the studs if they are out of the block. This will prevent leakage and corrosion.

G'day emrock32,
to PackardInfo, and I invite you to include your '31 Packard in the Packard Owner's Registry.

I had read on a other forum topic, that the advice for a smaller flat head, was to insert dry. I have all of the bolts out currently.

Now using permatex, would I still be able to re-torque when warm without messing up the sealer used on the threads?

Once the sealant on the block end of the stud is dry, it shouldn't allow the stud to move. I just did this job on my '37 115c, and after three re-torques, I had no leakage.

It is imperative that you lube the threads on the nut end of the stud. Measured torque with a torque wrench is a combination of running torque (the force required to overcome the friction inherent in turning the fastener) and the amount of force applied to fastener that then translates into clamping force. Torque specs in industry, even back in the '30s, assume lubricated threads thereby negating much of the running torque. Your head would not be tight enough and could cause a blown head gasket down the road if you installed the nuts and torqued them dry.

That's what I've always heard. I found it odd that the gentleman said dry. I have always used oil or sealant depending on the jackets underneath. Found it where odd when I saw that they were open to the coolant passages and required no type of sealer or washer for the bolts themselves.

Glad I cleared that up before torquing them down. I am new to building flat motors so I rather second guess myself instead of doing the work for a second time.

They are all in now. I am hoping for good results since the motor was only running on 5 cylinders before I did the valve job on it.

I appreciate the quick, and detailed responses. Saved me hours worth of work and mess later.

-Mark