348 Coolant Leak under Plenum

Once you pull out the bolts on the back of the intake you can just set aside the air injection solenoids. Not necessary to unplug it, just set out of the way.
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Ok, now you're ready to pull the plenum out to see what's going on down there. Double and triple check that everything has been disconnected and is out of the way. In Ernie's case, he had to lift the plenum (but not completely take it out), tip it back to disconnect the vacuum line for the intake compensation valve, then fish the MAF & TB connectors back and out through the intake runners. For some reason mine wasn't wired this way. Either way, when you're slowly lifting your plenum out, have someone look underneath to see if you need to do this the same way Ernie did. In my case, I didn't, I just removed the plenum and it came right out.

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And the problem was in the area circled in yellow here....
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Can you spot the location....
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Check the area circled in yellow...
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Water/coolant stains.....turns out the clamp was stripped. The hose/sleeve itself was still in perfect condition. Cost of this is $64 from Ricambi, I ordered it and replaced it regardless since I had it apart anyways. It is # 40 in this drawing. I also ordered replacement clamps (obviously), #41 in the diagram
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All in all, not a bad job, just takes time and patience (and a strong back HAHAHA).

Before I put the injectors back in place (attached to the fuel rail line), I cleaned the carbon build up with brake cleaner, and applied a little bit of vaseline around the o-rings.

 

I will add this the 348 DIY thread shortly....

 

Hope you inspected p/n 42 in the diagram. Mine was crumbling and leaking. Replaced with Hill Eng stainless steel fitting.

 

I did not. Is that accessible with the plenum in place? What is that part called and what is its function? Once I found the source of the leak I didn't think to check anywhere else.

 

Mine too. I used a standard brass fitting as a replacement.

Before:
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And after:
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Nice job Miroljub, mine wasn't corroded as badly but almost. To remove the fitting I put a drill bit that was a close fit inside the tube such that I could clamp some vice grips around it without it crumbling.....Also applied some heat to the manifold casting to aid in removal.

 

ATA boy Mikey! Great job!

 

Thank you Ernie. Thank you for your intake/plenum removal thread. That was the inspiration for me to do this myself

 

Mike - It is this: https://www.ricambiamerica.com/106241-union.html

 

Thanks Daniel.

 

Holy smokes!

 

Exactly

 

To remove that hose (122219), is it necessary to follow this tutorial and remove everything, or can it be done without removing anything? I see the clamp is difficult to remove.

 

which hose?

 

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I can double check for you in a few days, but to the best of my knowledge you cannot get to that house without removing at least a few things

 

where did you buy it, I have the same problem

 

That's how I have mine, do I need to cut it to remove it or does it have a thread and can it be unscrewed?

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I bought it in a shop in Kuala Lumpur selling brass fittings, hydraulic fittings, etc. The original fitting is as shown in an earlier post here but, with the amount of corrosion, I didn’t even try to unscrew it. Instead, I cut it, drilled out and cut a new thread matching the brass fitting.