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Access Ports


New Member
Mar 9, 2019
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Hello, I just got a 96 GMC Sierra SLE with a 5.7L L31 engine. First 350 eng. Probably bad steeper motors in 2 gauges as they quickly bounce around. I am wanting to put mechanical oil and water temp gauges in but according to schematics, disconnecting the oil will shut off fuel pump, and water will off set PCM and emissions. Runs smooth and great as is, so senders must be ok. Has towing pkg and oil cooler attached by oilfilter.
(1) Without going to the trouble to get to the Oil unit behind lower In Manifold with a tree, is there other place on this engine to get oil pressure?
(2) There's no room without removing manifold to drill and tap for water and the temp sensor has to dip into the passage to work properly. Can i get water from any other spot? Tks
There are plugs in the cylinder heads for water and there may be a oil access plug above the oil filter on the side on the block.

I circled the area

65 Sporty, Thanks for the info and I will try and locate them. Will update when I get it figured out. Will look closely again at the oil area, I know there are lines leaving theat immediate area for the oil cooler. Will let ya know.