so my father inlaw has this rotted out DD 96 bonnie se. he is leaking coolant, imagine that. he said he is up to over a gal a week. he brought it over a week or two ago and i looked it all over and cant really see anything obvious. so i figure its the lower intake since nothing has ever been done to this engine as he has had it since 98-99. so he dont want to put any money into it because it may fall apart tomorrow,and i was thinking about just reusing the upper stuff and resealing anything that looks rough with rtv, and blocking the lower intake coolant ports so there wont be any in the upper intake or tb. anybody see any problems with that? thoughts?

I see nothing wrong with blocking the coolant ports. But be warned. If your pulling 17 year old gaskets apart, even RTV couldn't fix them. I'm sorry to say but, he'* better off spending a few dollars now, then much more with towing or even worse stranded on the road with a hydrolocked engine when its 5 degrees outside.

i agree, i told him he should just do the whole deal ive been burned myself more than once. but thats not how he operates. so i said we could replace the lower gaskets, they are like 25 for the cheap felpro'*, put the plugs in the lower intake so there isnt coolant in the upper, and seal the upper and tb with rtv. it would just be air if it did get a leak in the future.

Im in middle of that process....but deeper. Im about to make a post, but as to this post. Whats with the coolant port blocking? Is it just for SC or Non? What do u gain from it?

at least on the non sc 3800'* the upper plentum is plastic and gets messed up from the heat cycles from the coolant and the egr. so the material in the tb area where the egr and coolant flow through will break down and start to leak. the new dorman upper kit has fixes for both these issues but i went a step further when i did my bonnie and blocked the coolant from being in the tb at all with plugs in the lower intake. its been done a bunch of times, i got it from some older posts from billboost.

https://www.gmforum.com/mechanical-1...2005-a-304071/

Yea that was great, i couldnt see the pics @ 1s.....but isnt those ports used to cool the tb?

Last I knew, the coolant ports were used to DEICE the throttle body in extreme cold environments. As in, Barrow Alaska.

Many others including my self have done the same mod with no negative effects.

Is there any other mods than should be done with this, or its safe alone...and nonSC..

If your good with a Dremel, you can port/polish the lower manifold runners.