Oil Leak

 I've always had a leak dripping from the bell housing so decided to try and tackle it.

On investigation, it appears that at least one of the culprits is the intake manifold rear seal. Seems like this is a common problem and I definitely found oil running down the back of the block which could be making its way down to the bell housing.

So, order of events,

• Drain coolant ( due for a change in any case)
• Remove Sump guard ( to drain oil later and change filter)
• Remove carburettor
• Remove Distributor - note I took several photos of the orientation of the cap and the rotor so that when re-fitted I could align them as close as possible so that the timing would be pretty much spot on. This assumed I was not planning to turn the engine over at all.
• Undo all hoses to the Intake manifold including heater hoses
• Remove Alternator cable.
• Remove Rocker covers.
• Remove Oil pressure senders ( gauge and light)

Once at this stage, undo all the Intake manifold securing bolts.

Now the hard part - getting the Intake manifold off. As expected this didn't just simply lift off as the builder had used plenty of RTV sealant. There was a bead running across the front and rear of the block as expected, so reasonably easy to cut through these with a Stanley knife. - but still no movement. It turns out that there was RTV surrounding the water passages on each corner of the manifold.

The eventual solution was to use a thin, flexible decorators trowel, carefully inserting between the manifold and the head on each corner. This cut through the remaining RTV an allowed the intake to lift off.

Its then a case of dealing with cleaning up the mating surfaces, removing all traces of the old gaskets and RTV. This actually too ages as the old gaskets were well fixed.

Once everything removed I used brake cleaner to degrease all the surfaces ready for the re-assembly.

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  Before we start

  

  Draining coolant

  

  Removing sump guard

  

  Alternator cable remove

  

  

  Capture orientation of rotor arm and distributor case for re-assembly

  
  
  
  
  
  
  

  

  With intake removed - note old bits of gasket and RTV
  
  

  
  
  

  

  Intake during clean up process
  
  

  
  
  

There are differing opinions on how to deal with the intake sealing. For definite you need a new set of gaskets which I got from RoadCraft. These are the Edelbrock ones to match the heads and intake.

Some folks fit the gaskets dry, but lots of internet folks and Edelbrock instructions suggest using something called Gasgacinch to tack the gaskets onto the heads, then run a thin smear of RTV around the coolant ports to ensure a seal.

However, being old school and remembering my Dad was a big fan of Hylomar Blue - that's what I used to tack the gaskets to the heads. As a compromise I used the smear of RTV as recommended around the water passages.

Consensus is you run a good bead of RTV along the top of the block wall between the heads, front and back. This bead needs to run up onto the Cylinder head faces to make sure the joint between the head and block seals.

Its then a case of reversing the process to put everything back together and keeping fingers crossed for no more leaks.