1800 Intake manifold bottom plug size?

[Fiat88]

I need to know the size and thread of one of the bigger plugs which go into the bottom of the manifold coolant passage? I thought it was an M18 x 1.5 like the oil pan drain plug but its too small. Any help would be apperciated!

[TulsaSpider]

There are some aluminum plugs that are on the bottom that you would think can be removed, however they cannot. Not sure if this is what you are referring to?

[Fiat88]

I tried removing those from my 2000 manifold but like you said they won't budge. I was just searching the miriafiori archives and came across this information which answers my post. I know number 1,2,4 are correct, will know if the 22mmx1.5 is the correct size tomorrow.

I'll assume that we are talking 1800 intake,correct?

1-The upper hole for the Egr thermal valve 18mm x 1.5

2-Lower side hole for EGR air pipe fiting 16mm x 1.5

3-Underside lower Large thermal switch 22mm x 1.5 - A fiat oil drain
plug, or trans and/ or diff add or drain plug will work here.

4- Underside smaller thermal switch 16mm x 1.5

I'm sure that there are probably some 'prettier' solutions out there if one
looks hard enough, like the nice little allens for the air injection ports as
mentioned previously.(McMaster-Carr pn 99642A205)

Hope this helps.

kd

[Fiat88]

Wait... I'm confused... my old fiat engine oil plug fits in the hole I'm trying to plug it has a 17mm head, the IAP website says the size is M18x1.5, so today I go to the store and buy one the same size with a flanged head and its too small. I think a 22mm plug would be too large? Back to the drawing board.

Just to clarify this is the middle hole of the bottom of an 1800 manfold. Anyone know for sure what the correct plug size is?

[narfire]

Perhaps I should check, but I believe I ended up using a Brass pipe fitting with JB weld. Threds were not quite the same but close enough and the JB did the rest.

[Fiat88]

Hmm, I was also thinking of trying jb weld around the threads.