cruisin69

My oil pressure gauge does not work. First of all, on a small block where do I find the oil pressure feed line that goes to the gauge? I found a plugged port near the oil filter, could that be the port I need? I haven't been able to find this in the Haynes manual.

Second, do I need to remove the gauge cluster in order to work on this?

I'm guessing that the gauge is not hooked up, and also that it is not functional. If that is the case, any suggestions on rebuilding the gauge, if so how do I calibrate it? Buy a new one possibly? It is the original gauge so I would like to keep it.

rainman69

The "original" place for the oil pressure sender was right on the top rear of the block, next to the distributor. There should be a place to screw in a mechanical gauge fitting. The fitting and line can be bought in a kit from an auto parts store.

Yes, you need to remove the cluster.

cruisin69

Thanks rainman69 for the info. This will be my first project on my vette (just got it a week ago), should be pretty fun. I've heard stories of oil dripping into the interior / on the radio, so I will need to be extra careful here...

rainman69

:lol:

My radio must be one of those "liquid" radios...it's full of oil, and unhooked.

The "proper" way to put the new line in is to attach it at the block using the supplied compression fitting. Then start the car, and once oil starts dribbling out the end of the tube (into a catch-can in the car) you can assemble and tighten the compression fitting on the gauge. If you don't do it this way, you'll get an air bubble in the line and the readings will be wacky.

If you don't know how to use a compression fitting, ask a guy in a plumbing parts store, or maybe someone here will know how to describe it...I don't.

GTR1999

You might want to get a pressure gauge to teat your motor oil pump. It should be 1/8" NPT tap in the block. Good advice about bleeding the line I had a vacuum develope on 1/2 crank once and bent the gauge needle backwards a little. I had the gauge stop working once and it turne dout to be a cushion behind the gauge dried out and came loose. It wedged in the gauge and stopped it from moving. The plastic line is avaliable at NAPA.
Gary

cruisin69

Well, I got home late last night and therefore was able to tinker around only a little bit. I found the fitting and pressure line coming out of the block, so at least I know I have one now. Then I proceeded to take apart the center instrument cluster. I think I have to take apart the right dash panel too, to get at the radio better. Apparently the radio needs to be taken out before the center panel is able to be removed?? I actually ran into a problem with the clock ****, it looks like it should be taken out before the center panel is taken out, and I tugged and turned it... I couldn't get it out though, is there a trick to this? I was being real careful though... didn't want to break it. :crazy:

gerry72

The clock adjustment **** is held on by a tiny screw in the center of the ****.

cruisin69

I was turning that screw, but it just kept spinning. I'll try again... Thanks

Surfer69

Just did this two weeks ago, I only took right dash panel off and loosen front cluster and could get to back of gauge with a little effort. Put tube in baggie before attaching to back of gauge, turn engine on and make sure oil is flowing. Make sure comp fitting is on correctly. Dont need to bleed tube before installation any air is still OK. Make sure tube is long enough, mine had no room for play so had to disconnect from engine (after I checked flow) to get it connected to gauge. My .02

bb69

Well Len,
I'm glad you finally started your first real project.

For everyone else, I find it to be my duty to tell you that we introduced Len to a little stoplight fun the other night. Judging by the smile on his face, I think he liked it. And, brace yourself now, Len told us he needs a little more horsepower. :D :D

Len, this is one of those things where if Napa has the part, don't buy something from the specialtly Vette stores. They will charge more, and a piece of tubing either works or doesn't. If you get the gage out, we can apply pressure to it at my house and see if it works. See you tomorrow. :cheers:

cruisin69

Yes Ken, the stoplights were a lot of fun. And productive as well, due to the fact that you and Brandon noticed the excessive burning of oil when I really put a load on the engine. (my winter project) I couldn't smell it, so I probably would have never found out... until it became a bigger problem. Driving around with three 69's vettes was a blast! How often do you see that on the streets? I'll try to get that gauge off tonight. What's to know about the compression fittings? I guess I would press the tube in as far as it would go and then tighten the compression nut, anything else I should know??

cruisin69

Got to work on it this weekend, with a friend of mine. :smash: It wasn't too hard to take apart the instrument cluster. Got the oil pressure gauge unplugged, and then started the vette - and oil did squirt out of the line. Next step - examine gauge: It was interesting to discover the inner workings of the oil pressure guage. It contains a bladder (looks like it's made of thin copper), which is curved. When the oil enters the bladder, it rolls open slightly, and pulls on a linkage wire which is connected to the rack gear (it looks like a quarter of a circular disk with gear teeth on the end of it) which then turns the shaft of the needle (which has the gear teeth built into it). To make a long story short, the "rack gear", in my opinion, is of poor design. The reason being that if the linkage wire becomes loose, then the dead weight of the rack gear will actually cause the gauge to give a false reading (in my case it was stuck at a little over 35 psi). So, it took some careful adjustment of the wire to eliminate the slop and even more adjustment to calibrate it. I used a small air compressor, and adjusted the link until the gauges matched. Well, the linkage wire had to be adjusted so many times that it broke, and I also broke the tab that is spot welded to the bladder which holds the linkage in. :cry It didn't take much to break the tab. Anyway, I bought some steel wire and will fab up a link that will stay in without a tab. I also worked on the clock (original mechanical). It was pretty cool to find out how that thing worked, has anyone ever replaced the tension spring inside there? Anyway, I got it working again, messed around with it hooked up to my car battery. I took some pictures of all of this and will post it when I get them developed. Next step: put it all back together... By the way, I hooked up the oil gauge by itself, and my engine idled at about 35 psi. No leaks either!

BB wowbagger

Congrats..You are now one of the lucky few with workin`original clocks..I`m not one of the lycky few,but i will be ....soon :smash: :smash: