Hey all, Tired of banging my head so I thought ask the experts. I love the passion in all of you. I have a mid 60's 283 set up in a vintage fiberglass boat and was just going through the final few items when I got a little fancy and set myself back. The boat came with two oil pressure gauges and a broken rod through the sidewall. Looked like the original gauge was not connected and replaced by a mechanical one that was not even mounted. They ran from the port at the back near the distributor. When I put it back together I plumbed the original sending unit into the same port but still wondered about why it had been disconnected. I decided to hook up the second unit to a port just above the oil filter but needed an adapter to run the mechanical gauge fitting. Thought it wouldn't hurt to compare the readings and once I was happy I could run a warning light instead of the second gauge. Packed up and off to the local parts store with the sample only to find they couldn't match the thread. Somewhere along the way with the list of other items the sample I gave turns up missing by the time I get back home. Back to the parts store but nothing. It is not 1/4" pipe thread. A plug that screws easily into the water jacket opening on the side of the block does not fit. I removed the plug from the old block and it threaded easily in by hand so it must be a factory thing. No one seems to know. Parts store doesn't have a sending unit or a plug. It's no national emergency and eventually I will figure it out. Just thought I would ask if it is possible that it is not 1/4" pipe thread? Comments appreciated and welcome. Thanks in advance and all the best to everyone. RJC Dryden, Ontario, Canada
Thanks for the suggestion. It was a good one. 1/8" NPT did not work though. Time to hit a junk yard and find another SBC
I believe you are mistaken in thinking the hole above the filter is for an oil pressure gauge. I think only big blocks had a sender hole there.
All of the ones I have seen were 1/4 pipe. I have had a lot of those out. Have you ran a 1/4 pipe tap into the hole?
That was going to be my next question if I could run an oil pressure sending unit from that location. Things are changing. Thank you
Found the one I need. Came with a 1975 350 with the 4 bolt mains. Pretty happy about the sudden turn of events. Engine number says 165 hp. Curious about camshafts now and what the stock cam represents in term of lift and duration. Guessing more tourque than the 283 and looking forward to spring. Thanks for the help.
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