Manifolds on my 48 D-24

[bighammer48]

Guys,

 

I bought new intake and exhaust manifolds for my D-24. The shop manual only lists the torque spec. There are no directions for installation. Do I bolt the 2 together first( 4 bolts near the carb mount ), or do I bolt them loosely to the engine, then snug the top and bottom halves where the carb mounts, then tighten to the engine finishing the top/bottoms last? Or, do I tighten completely to the block first? I DO NOT want to induce a crack in either piece. Help, please!

Edited February 21, 2016 by bighammer48

[Branded]

Tighten to block first, can't remember to torque specs but someone will chime in I'm sure.

[bighammer48]

hanks. Torque spec is 15 -20 lb.-ft. It's in the shop manual.

[dpollo]

When the parts were new, the intake stood proud of the exhaust flanges by a very small amount. This allowed the intake to be tight while allowing for some movement on the outer end of the exhaust.

 

  Just make sure you draw all the nuts  and bolts up evenly and be sure to use the correct washers especially the brass ones on the exhaust .  If they are not available , use a flat washer which will allow some expansion and contraction.  The intake does not use washers on the  drilled holes, the other fastening points use a thick slightly cupped washer. 

 

 The post following this gives more good advice.   In my original post, there was an error about washer use

 

 my apologies for not proofreading.

Edited February 22, 2016 by dpollo

[greg g]

I would recommend that you assemble the manifolds together loosely, then install the assembly and tighten the assembly to the block starting from the center out.  leave them hand tight (snug then a quarter turn) for a heat cycle then firm up from the center out to the spec'ed torque.

[bighammer48]

Thank you, as always!

Edited February 22, 2016 by bighammer48

[greg g]

don't forget to tighten the bolts between the manifolds.