Intake Gaskets & Torq Values

N1478D · Post by **N1478D** » Tue May 24, 2005 6:23 pm

While the exhaust and one cylinder is off one side am replacing the intake gaskets. Does P/N 24759 Intake Manifold-To-Sump Gasket go on dry? If not, what is best to use? With the sump being magesium and easy to crack, are there special torq values? I always have trouble finding those. Since they are not in my engine overhaul manual, maybe they are in the early Cessna Service manual? Thanks In Advance!

Later, after post I remembered the Service Bulletin!

In reading SB96-7B, I still don't see the intake Manifold to Sump information! On top of that, the Cylinder Torque Procedures on page 2 are confusing. 1. says torque cylinder base nuts to 1/2 of the specified torque value. 2. refers to cylinder base stud nuts. What are the cylinder base nuts and what are the cylinder base stud nuts? Are the base stud nuts the nuts on the thru bolts? And the base nuts all of the other nuts?

dacker · Post by **dacker** » Tue May 24, 2005 8:26 pm

Joe, while I don't have it with me, what you should be looking at is the Continental manual for the O-300, I believe available from Spruce or WAg Aero or Univair. It is a must have for your Aircraft Library.
David

N1478D · Post by **N1478D** » Tue May 24, 2005 8:41 pm

You are right George, I mean David!

I have the Continental "C" Series 6 Cylinder Aircraft Engines Models C125, C145, and O300-A, B, C, D, E Overhaul Manual.

What I don't see in the manual and in the Service Bulletins, although I am rereading SIL99-2A to see if I can find info on the gasket being dry or not, is a specific call out for the induction system torque values. I know there is a generic chart based on size, but with the material being magnesium, was wondering if I have over looked a more specific value stated somewhere.

All of these bulletins, service information letters, manuals, etc are information overload for someone who occasionally dabs in to their content.

dacker · Post by **dacker** » Tue May 24, 2005 10:36 pm

OUCH!!! Call me anything but slow (I mean George). Sorry Joe, I didn't mean to sound condescending. I am really ashamed now, because I realized that I had the same problem finding those same exact torque values a couple of years ago when I had an oil sump leak. I do believe that I used the torque values from the charts (from the 43.something or other). I beleive one of our crafty mechanics on the site can give you better direction than me.
David

Post by **GAHorn** » Wed May 25, 2005 5:08 am

There's no difference in the torque values simply because the studs are mounted in magnesium. Use the standard values as listed in the TCM Overhaul manual.
Gaskets may be installed dry in intake manifold service.

spiro · Post by **spiro** » Wed May 25, 2005 6:00 am

a thin coat of DC4 on both sides of gaskets like these sure makes dissassembly easier.

paul

Wed May 25, 2005 10:51 am

This link has been posted before by at least George and maybe others.

http://www.tcmlink.com/pdf2/SB96-7B.pdf

This will get you a SB which has EVERY torque for EVERY engine EVER made by TCM.

When I was rebuilding my engine I had a question similiar to yours but for different studs. I called TCM. The guy said if I couldn't find the torque in the SB TCM didn't have one and to use standard torque for the fastener what ever I determined that to be. When I asked if it mattered that the stud was screwed into a helicoil in aluminum and I was afraid I'd pull the stud and helicoil he said something to the effect not if the helicoil was installed right and "Oh well, stuff happens".

Thanks TCM tech support guy

N1478D · Post by **N1478D** » Thu May 26, 2005 2:47 am

THANKS for the help guys!

After reading SIL99-2A, I sprayed the new gaskets, not the flat one, but the three hose types, with WD40. Hope it helps, sure made them look good.