Oil Pressure Regulator Questions

[65beam]

oil

Mike / Ken,
I'd bet he'll soon have everything he needs.

 

[zack]

I don't have a thread pitch gauge. I've gotten by with matching up TPI and thread OD against charts.

Mike

No problem. 65Beam just messaged me that he is throwing in a disassembled valve that I can work with.

 

[zack]

I completed the drawings for the thin model units (stock, not modified), with all parts including the two tube versions and spring information. Now it's just a matter of getting it onto the site; the DWG in a zip file is 180K which is larger than the maximum attachment size. I also exported a JPG but that is several times larger than the 640x480 limit. Then I tried a pretty low quality PDF and that was over the limit too. It is currently on a free hosting site that probably won't exist in a year or two so if someone can get it onto a server that will basically host it until the end of time that would be great.

http://s000.tinyupload.com/?file_id=15576892957851573657

[edit]Nevermind, found a better server for it.
https://grabcad.com/library/thin-style-sunbeam-alpine-opr-s-stock-style-1

 

[hartmandm]

I parked a copy of Zack's docs on my site as well.

http://mhartman.net/files/sunbeam/Series V OPRV part 5043949.dwg
http://mhartman.net/files/sunbeam/Series V OPRV part 5043949.jpg

Mike

 

[zack]

I received the later model housing and dead valve yesterday. After measuring it, I designed a new valve for this design. This was much easier than the original design. The screengrabs don't show it very well, but the whole tube would have outside threads of 5/8-24; it threads into the cap as well as the oil filter mount. There are two spring pins in the cap. This means that when it comes time to remove, the whole tube will come out...it won't just be the cap turning off and leaving the tube behind.

It is adjustable with a 3/8-24 screw. A wide range of possible pressures will be available but if set for 35PSI initial opening, full open will not be reached until 70PSI. Of course if the pump does not have enough flow then the maximum PSI will be less. This is all based on one spring I found using a spreadsheet I created from the McMaster Carr website. The spring is a pretty common size so there would be a lot of extra possible combinations if one wanted to get a stronger or weaker spring. The spring sits inside blind drilled holes in the piston and the piece between the adjustment screw and the spring. This keeps it from going off center/rubbing the walls/getting stuck in the dump and seep ports/etc. Both ends of the piston are radiused with .02" fillets so that even with wear it will resist sticking, while still providing the surface friction to reduce excessive movement.

I also made the hex portion about 3x longer than stock. This way, a box-end wrench or even gear wrench will easily clear the housing...making it easier to install or remove.

Ideas/comments/etc?

 

[hartmandm]

I find the shallow head bolt on my brass OPRV, with an adjustment screw mounted through the bolt head, can be loosened and tightened easily enough with a 1/2" drive socket. There isn't any spare space though when using the socket. So you can go either thin head bolt and use a socket, or go thicker bolt head and use a wrench. Either works. Whichever setup is easier or cheaper to manufacture makes sense to me.

Mike

 

[Ken Ellis]

Zack, although all the oil filters I've used recently are tall and thin, I think I recall some fat ones in the past -- ones that hang out past the oil filter plate, and get pretty snug to the block. Will your longer design accommodate filters in that profile?

 

[Tom H]

I agree with Mike. I can remove the OPR easily with a socket and 3/8" drive, but there is not much room for a taller hex head.

Tom

 

[zack]

I find the shallow head bolt on my brass OPRV, with an adjustment screw mounted through the bolt head, can be loosened and tightened easily enough with a 1/2" drive socket. There isn't any spare space though when using the socket. So you can go either thin head bolt and use a socket, or go thicker bolt head and use a wrench. Either works. Whichever setup is easier or cheaper to manufacture makes sense to me.

Mike

I looked at my design a few times and having a larger head would make it a stronger part that is less likely to leak, especially with that adjuster screw. However, that thickness doesn't necessarily have to be coming out of the cap...it could be going into the body. For the adjustment, you would need to get a wrench on the cap as well as another wrench on the nut touching the face of the cap. Would this be easier if the hex went out some particular distance?

Zack, although all the oil filters I've used recently are tall and thin, I think I recall some fat ones in the past -- ones that hang out past the oil filter plate, and get pretty snug to the block. Will your longer design accommodate filters in that profile?

With the angles, it really couldn't get in the way of any filter unless it curved back down (I've never seen such a thing but it's possible I guess). The filter might get in the way of the valve as far as doing adjustments.

 

[zack]

I did a few iterations and then made one. Tested it and it worked well. Unfortunately, it seems driving home on zero oil pressure killed the bearings because once it is hot oil pressure is almost nothing even if it is tightened down so much that it is basically just a plug...but that's a story for another place; the valve worked great. The models are up on grabcad for anyone who wants them. They are in SolidWorks format; these are what I used when machining the parts and basically any machine shop should be able to use them. If you want to view them yourself there is a free program called eDrawings that will work with these. I'm giving open permission to use these for personal use, distribute them, modify them, etc. In the (unlikely) event that someone starts making tons of them for sale, I'd appreciate a small kickback for the design work.

Materials used: Cap is 6061 Aluminum, the piston, screw adapter, and tube are 931 bronze. Other materials would likely work fine; I used these for local availability and easy machining with crummy equipment and tooling. If using something with lots of thermal expansion, you may need a bit more clearance between the piston and tube ID sizes; as they are the fit is RC5 at ~ 160-190F.

https://grabcad.com/library/sunbeam-alpine-late-model-opr-1