AndyF07

Active Member
I have a 2002 4.0 P38 and have just replaced the exhaust system from the manifolds backwards. I am just about to torque everything up and checked RAVE. I am sure I am misreading something but there seems to be two torque values for the front pipe to manifold bolts. On page 11 of the repair section ( 30 Manifold and Exhaust System ) it says 50NM for 'from 99MY' but it the Torque Values ( 6 Torque Values ) it says 30NM.

Can anyone shed any light please as can't find an answer?

Thanks for any advice!
 
I have a 2002 4.0 P38 and have just replaced the exhaust system from the manifolds backwards. I am just about to torque everything up and checked RAVE. I am sure I am misreading something but there seems to be two torque values for the front pipe to manifold bolts. On page 11 of the repair section ( 30 Manifold and Exhaust System ) it says 50NM for 'from 99MY' but it the Torque Values ( 6 Torque Values ) it says 30NM.

Can anyone shed any light please as can't find an answer?

Thanks for any advice!

RAVE does have some errors and inconsistencies. If it is going into aluminium then I would try 30 Nm and recheck after a week. If it is steel on steel then 50 Nm should be safe as long as the bolt is big enough. Be careful with anything M5 or below as they shear off for fun.
 
Thanks @Grrrrrr. There is a slight leak on both joins at 30NM although it's complicated slightly by the fact I wasn't sure which way round the gasket went (i.e ridged side into manifold pipe or front pipe. I will double check size of bolt before going tighter. I had to drill two of the old ones out which sheared so really don't want to do that again ;);)
 
Thanks @Grrrrrr. There is a slight leak on both joins at 30NM although it's complicated slightly by the fact I wasn't sure which way round the gasket went (i.e ridged side into manifold pipe or front pipe. I will double check size of bolt before going tighter. I had to drill two of the old ones out which sheared so really don't want to do that again ;);)

I don't think the ridge side really matters but I would have put the ridge the engine side of the join.
 
Always start from the middle of the manifold and then work your way towards the ends. It maybe worth checking it's not deformed before fitting ;)
 
If you're ever putting a bolt in, particularly with ally, you can always sacrifice the old bolt and with a grinder cut a groove up its shaft and with a bit of moly grease just run it in and out the hole a few times before reassembly. Helps with getting the torque right. Obviously you'll have to clean that up if you're putting Loctite in it.
 
If you're ever putting a bolt in, particularly with ally, you can always sacrifice the old bolt and with a grinder cut a groove up its shaft and with a bit of moly grease just run it in and out the hole a few times before reassembly. Helps with getting the torque right. Obviously you'll have to clean that up if you're putting Loctite in it.
Done that with a spark plug to clean up spark plug threads in an alloy head
 

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