Valley Gasket Replacement

[jack350]

Changing the above, however when disassembling noted no sealant between plenum and plenum base, no sealant between base and manifold and no sealant around the inlet ports. Original gasket is composite.
what are the thoughts here - to use a smear of sealant or not?
Phil

[Zener]

Use no sealant round the composite inlet manifold gasket to heads inlet ports (no need) if you want to smear the coolant ports thats fine, trumpet base to inlet manifold and plenum to trumpet base Wellseal or Hylomar (not RTV compounds) these are old school but still capable sealants and easily removed with carb/brake cleaner , your only sealing joints with vacuum and the above can do this with ease , if you want to go posh Loctite 515 or 518 flange sealant

[jack350]

Many thanks
Phil

[adam quantrill]

Yeah I added a smear of blue stuff around the coolant ports on mine as I thought the gasket was a bit weedy in this area. Worked fine.

[jack350]

Hi Adam
Will do the same
Do you have any idea what the torque setting is for the 'plenum base' bolts i.e. not the plenum itself, the unit it sits on which bolts to the inlet manifold
Phil

[Zener]

Trumpet base to inlet manifold 26nm or about 18 ft Ib old money , plenum to trumpet base 15/18 ft Ib will do ya

[Markymark21]

From experience I have found that to stop the valley gasket leaking oil, you need to use sealant at each end of the valley at the lowest point. From memory, the gasket kit will come with rubber insert pieces that go in to bridge the gap between the heads. Use RTV sealant or similar to seal the ends of the rubber inserts.

[adam quantrill]

My gasket came with the wrong inserts so I reused the old ones (again with a smear of blue stuff) and haven't had any problems.

[jack350]

Many thanks
Thought I would give the exterior of the manifold a bit if a clean whilst off. Quite a bit of oxidation - any recommendations of what to use?

[adam quantrill]

Assuming it's a mild steel manifold, I don't particularly clean mine, but I keep slapping this stuff on, which keeps the rust away:

https://indestructible.co.uk/product/ip9036-r1-hig...

[jack350]

Hi Adam
Its the inlet manifold I have off which on mime is cat aluminum
Just wanting to remove oxidation and clean up slightly?
Phil

[adam quantrill]

Ahh the other manifold. A drill-mounted wire bush maybe? Then spray with WD40.