What is the intake plenum on an '89 LN3 composed of?

[89RedDarkGrey]

What is the intake plenum on an '89 LN3 composed of? Cast aluminum? I ask this because years ago- the front of the engine developed a coolant leak. It turned out to be the flattened & hard O-ring of the metal pipe, that goes into the timing cover. After replacing both O-rings, the other being on the metal tube to plenum, with a paper thin white metal tab and 1 bolt to hold it in- and seeing what a flimsy design the prone-to-rotting tubing is, I want to tap threads in the timing cover when it's off soon (for new parts) and plenum for barbed brass nozzles, and use hoses to the heater core. There is already one in the plenum now- why couldn't they simply use 2 more?

 

  It's easy to stuff an oily rag in the plenum hole when drilling & tapping. When finished- slowly pull out the rag.

 

Does this sound doable?

 

[2seater]

7 hours ago, 89RedDarkGrey said:

What is the intake plenum on an '89 LN3 composed of? Cast aluminum? I ask this because years ago- the front of the engine developed a coolant leak. It turned out to be the flattened & hard O-ring of the metal pipe, that goes into the timing cover. After replacing both O-rings, the other being on the metal tube to plenum, with a paper thin white metal tab and 1 bolt to hold it in- and seeing what a flimsy design the prone-to-rotting tubing is, I want to tap threads in the timing cover when it's off soon (for new parts) and plenum for barbed brass nozzles, and use hoses to the heater core. There is already one in the plenum now- why couldn't they simply use 2 more?

 

  It's easy to stuff an oily rag in the plenum hole when drilling & tapping. When finished- slowly pull out the rag.

 

Does this sound doable?

 

Yes, the manifold is cast aluminum. I have never had those parts give trouble before but I have seen severe pitting where the hose connection end. It can be tapped for pipe fittings although clearance for the hex wrench might be pretty tight where the hole enters the front cover at a shallow angle. Try a search for heater hose nipples or connections and there are several different types, lengths and materials. Hard to beat the compactness of the steel pipes?

[Ronnie]

I think this may be a problem we might all experience as our cars age so I moved the above  posts to this new topic so the information didn't get lost in the other topic.