Oil pressure

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Ok, just got back from a test drive and it went well, so it must have been the sending unit. The mechanical gauge actually registered a bit higher at cold fast idle. Just under 85 psi, then at hot idle 25-30 and at cruise speed about 60-65. It never bounced around like the electric one, no erratic movement either. It does move pretty quick with engine speed, but sometimes the electric one would go down when I punched it and the mechanical never did. I did mount it in the cab temporarily, but it’s gonna get put in permanently too. I just need to figure out exactly where I want it. I did cruise back to the automotive store where I got it and got some copper line for it . I just don’t trust that plastic hose that comes with it.

Anyway, thanks again guys for the help!

 
I had a bronco II that used to do the same thing, cold it showed great oil pressure on the gauge, hot, would show around around 40 when driving but would drop down when I was sitting at a light. Engine sounded great and never caused issues but ended up selling it before finding out if it was a problem. Post back if you find anything out because I am in the middle of an engine rebuild now and if there is something that I need to change or add to mine to prevent this, it would be good to know now.  I will be watching this thread closely. Thanks and good luck brother.

Tom
Tom, I was just having a sender issue, not a oil pump problem, thankfully. Anyway I would go with a std volume pump. Plenty of pressure and it’s better for your engine. Thanks and good luck with your build!

 
Looking forward to the results. Bosch mechanical is what I have. I actually chose that brand because they are down sweep so look more like originals more that did they work the best.
I looked for the ones you got Geoff, but I couldn’t find them.
Oh well not to worry. You can change it later if you feel like it. So, do I read into your reply to Tom, that you found out it was just the sender that was clapped out?

 
Looking forward to the results. Bosch mechanical is what I have. I actually chose that brand because they are down sweep so look more like originals more that did they work the best.
I looked for the ones you got Geoff, but I couldn’t find them.
Oh well not to worry. You can change it later if you feel like it. So, do I read into your reply to Tom, that you found out it was just the sender that was clapped out?
You must’ve missed my post about it, but ya it had to be the sender.

 
PLUS ONE on the plastic oil pressure line, I've seen the aftermath of one failing. In the unlikely event of a copper tube one failing all you have to do is bend it over and smash it.

 
I looked for the ones you got Geoff, but I couldn’t find them.
Oh well not to worry. You can change it later if you feel like it. So, do I read into your reply to Tom, that you found out it was just the sender that was clapped out?
You must’ve missed my post about it, but ya it had to be the sender.
Awesome! That's a relief for sure.

 
Oh well not to worry. You can change it later if you feel like it. So, do I read into your reply to Tom, that you found out it was just the sender that was clapped out?
You must’ve missed my post about it, but ya it had to be the sender.
Awesome! That's a relief for sure.
For sure, I was pretty worried.

 
John, good call on going copper line. Perhaps I can offer something that I did when installing my gauges. As I also had the temp as a mechanical, it came with a very fragile gas filled tube permanently attached. Finding a place to drill a 1" diam. hole was NOT easy. I used the double hole grommet the NPD sell for the brake and fuel line through the shock tower which was perfect for the two lines. On the copper oil line, I did F up and miscalculated the length, so I was not able to put a loop in it for vibrations. See pictures below. I also slid a piece of rubber tube over it for more protection and to sort of hide it, I mean a bright shiny copper tube would look out of place imo. You're only running one line(for now) so a smaller grommet would be okay and easier to drill.

The temp line is hidden within the wire loom to the distributor.



This was the only place I could find where to drill without pulling the heater plenum out, a real PITA!!



Yellow arrow, copper line covered with rubber tubing. red arrow, idiot  light oil sender I chose to keep working.

 
John, good call on going copper line. Perhaps I can offer something that I did when installing my gauges. As I also had the temp as a mechanical, it came with a very fragile gas filled tube permanently attached. Finding a place to drill a 1" diam. hole was NOT easy. I used the double hole grommet the NPD sell for the brake and fuel line through the shock tower which was perfect for the two lines. On the copper oil line, I did F up and miscalculated the length, so I was not able to put a loop in it for vibrations. See pictures below. I also slid a piece of rubber tube over it for more protection and to sort of hide it, I mean a bright shiny copper tube would look out of place imo. You're only running one line(for now) so a smaller grommet would be okay and easier to drill.

The temp line is hidden within the wire loom to the distributor.



This was the only place I could find where to drill without pulling the heater plenum out, a real PITA!!



Yellow arrow, copper line covered with rubber tubing. red arrow, idiot  light oil sender I chose to keep working.
Hey Geoff, thanks so much for the great info and pics! I really like the rubber tubing over the copper line idea. I will definitely do that, cause you are so right about how out of place the bright copper line looks. I was able to route the oil line through the hole and grommet for the speedometer cable, so I don’t have to cut any holes.

 
As I was running two tubes, oil and temp, I had no choice but to drill a friggin hole which I did NOT want to do, but no other option.

NOTE to anyone wanting to do this; buy a really GOOD 1" hole saw. A step drill will not go through far enough to get to 1". 

Glad you were able to get it through with the speedo cable and glad the pics will help.

Let us know when it's all done and dusted.

PS< there was already a brass "T" under the idiot light sender. If yours doesn't have one, easy to get, I think 1/4npt to 1/8npt (oil tube fitting)

 
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So I got the copper line installed today. Took me quite a while, cause I just didn’t know where to put the gauge. I would have to remove the center gauge panel, again, to try to get it in. Just to much work to change, so for now I just put it under the dash.

I had it on the left side at first with the plastic line, but It’s in the way of getting in and out of the car. I put it on the other side with the hard line. It’s kinda temporary still because I didn’t have any holes already there like I had on the other side. I didn’t really want to drill any holes either, so I improvised by using velcro. Ya I know, half ass, but I have some industrial strength stuff and it really works well. The backing sticks really good and with the hard line zip tied down, it’s pretty solid. Good enough for now till I figure out what exactly I’m going to do. I would rather have a mechanical oil pressure gauge anyway. 

Thanks to Stanglover for the idea of putting a black rubber hose over the copper to hide it. The line with the loop is the copper oil pressure line. I was able to get it through the speedometer cable hole with no problems. I did make sure to leave some extra line on the inside in case I need to move it to a different spot.

Here’s a couple pics of what I ended up doing. Thanks again guys!









 
Looks pretty damn good John. Perhaps just leave it for now and make it a winter project to replace the center electronic gauge, or when you "feel like it" You might decide to buy a matching set later anyway. I think if I remember, you made a gauge mount similar to mine, so reinstalling gauges shouldn't be too hard apart from all the work required to get the damn dash apart again.

So, how's it running now?

 
Looks pretty damn good John. Perhaps just leave it for now and make it a winter project to replace the center electronic gauge, or when you "feel like it" You might decide to buy a matching set later anyway. I think if I remember, you made a gauge mount similar to mine, so reinstalling gauges shouldn't be too hard apart from all the work required to get the damn dash apart again.

So, how's it running now?
Thanks Geoff, ya it’s not really what I wanted, but good enough for now. I did think about taking dash apart, for about a minute, lol then I figured the same, it can wait. Plus I will have to drill new holes in the bracket I made cause the studs that hold the gauges in are of course different. It’s going to be a real pita. I did find a Bosch gauge online that’s very similar to yours, but not sure if it will fit. 

The gauge I just installed was the only thing the local automotive parts store had, so that’s why I got it. I just needed a mechanical gauge so I can keep a good eye on my new engine. Should have just done this to begin with instead of trusting an electric gauge. Oh well

Car is running good, but every time I say that something screws up! Lol. I still need to start it up to make sure new line isn’t leaking. Hopefully I can go for a drive today and make everything is good to go.

 
Looks pretty damn good John. Perhaps just leave it for now and make it a winter project to replace the center electronic gauge, or when you "feel like it" You might decide to buy a matching set later anyway. I think if I remember, you made a gauge mount similar to mine, so reinstalling gauges shouldn't be too hard apart from all the work required to get the damn dash apart again.

So, how's it running now?
Thanks Geoff, ya it’s not really what I wanted, but good enough for now. I did think about taking dash apart, for about a minute, lol then I figured the same, it can wait. Plus I will have to drill new holes in the bracket I made cause the studs that hold the gauges in are of course different. It’s going to be a real pita. I did find a Bosch gauge online that’s very similar to yours, but not sure if it will fit. 

The gauge I just installed was the only thing the local automotive parts store had, so that’s why I got it. I just needed a mechanical gauge so I can keep a good eye on my new engine. Should have just done this to begin with instead of trusting an electric gauge. Oh well

Car is running good, but every time I say that something screws up! Lol. I still need to start it up to make sure new line isn’t leaking. Hopefully I can go for a drive today and make everything is good to go.
Sounds like a plan, man!

PM me if you want more info on my install of Bosch gauges.

 
Took the car out for a drive yesterday to see how the Velcro holds the gauge while driving. No problems at all, it stayed right where I installed it. I figured it would, but I had to see what happens when I hit a bumpy road. No problem finding one of those around here! Anyway, it’s actually pretty solidly attached with it being connected to a hard line. I can even get to the fuse box easily. Good to go, Thanks again for the help!

 
Took the car out for a drive yesterday to see how the Velcro holds the gauge while driving. No problems at all, it stayed right where I installed it. I figured it would, but I had to see what happens when I hit a bumpy road. No problem finding one of those around here! Anyway, it’s actually pretty solidly attached with it being connected to a hard line. I can even get to the fuse box easily. Good to go, Thanks again for the help!
 That's great John. So it looks more like a bad sender on the electric gauge eh!

 
Took the car out for a drive yesterday to see how the Velcro holds the gauge while driving. No problems at all, it stayed right where I installed it. I figured it would, but I had to see what happens when I hit a bumpy road. No problem finding one of those around here! Anyway, it’s actually pretty solidly attached with it being connected to a hard line. I can even get to the fuse box easily. Good to go, Thanks again for the help!
 That's great John. So it looks more like a bad sender on the electric gauge eh!
Ya I think so. I will probably get a tee and a new sender and use both.

 
Maybe the electric gauge's signal wire is getting some weird interference from another wire? Like maybe its near an ignition wire or something? Just throwing ideas out....

Get ready for the snow....

-Matt

 
Maybe the electric gauge's signal wire is getting some weird interference from another wire? Like maybe its near an ignition wire or something? Just throwing ideas out....

Get ready for the snow....

-Matt
Yeah, it's snowing here in SWO, but just lightly. I've had enough!!

Good point on possible interference.

 
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