# PM 833TV One shot question



## fishingreg (Jun 2, 2020)

Since I received my 833 it has leaked the oil from the one shot system.  It took about 2 weeks and every bit of it leaked out.  I did not pinch any lines when I set it up, I was very careful about that.  I can not find a leaking fitting but if I had to guess based on where it is, I think it is in the X axis.  Has anyone else had a leak when they got it and if so, was it just a loose fitting?  I don't want to tear the machine apart to find it but I may not have a lot of choice.  Another option I thought about is putting a valve at the fitting as the line comes out of the pump so I can just open the valve, pump it and close it, that might be the easiest fix.

Thanks,
Greg


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## wrmiller (Jun 2, 2020)

I have similar issues with the one-shot on my PM935. I'll give the lever a couple of pumps and notice the next day that I've lost half the oil in the little tank. I'm pretty sure I can fix it with a shut-off valve between the tank and the XY lines. But I haven't found a valve yet. Not that I've really tried looking that hard yet. 

If you do find a shut-off valve, I and others here might appreciate a post telling us what you found


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## fishingreg (Jun 2, 2020)

wrmiller said:


> I have similar issues with the one-shot on my PM935. I'll give the lever a couple of pumps and notice the next day that I've lost half the oil in the little tank. I'm pretty sure I can fix it with a shut-off valve between the tank and the XY lines. But I haven't found a valve yet. Not that I've really tried looking that hard yet.
> 
> If you do find a shut-off valve, I and others here might appreciate a post telling us what you found



I'm glad to hear I am not alone although not wishing issues on anyone.  I will get some fitting sizes and start looking for a valve to fit it.  I hate losing all my oil when I am not using it.  Not to mention, its a lot to clean up.


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## mksj (Jun 2, 2020)

I would look into a one-way check valve that has an opening pressure of 5-10 PSI, this could be installed at the junction of the pump to the flexible tubing. You will need to know the size/thread pitch of the current hose. See page 10 on the BIJUR SPECIALTY FITTINGS 151. There should be enough resistance with the check valve installed to prevent oil from free flowing due to gravity. Second file is more FYI, thought is was helpful as flow rates for line resistance fittings.


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## fishingreg (Jun 2, 2020)

mksj said:


> I would look into a one-way check valve that has an opening pressure of 5-10 PSI, this could be installed at the junction of the pump to the flexible tubing. You will need to know the size/thread pitch of the current hose. See page 10 on the BIJUR SPECIALTY FITTINGS 151. There should be enough resistance with the check valve installed to prevent oil from free flowing due to gravity. Second file is more FYI, thought is was helpful as flow rates for line resistance fittings.


Thank you, I might try that.  I had not considered a one way valve since it is the direction it needs to flow but that makes sense about needing pressure to flow.  

I have found and ordered a valve that I think will fit based on my best guess at the treads from the elbow going to the tank fitting.  If those threads are not correct I will for sure look up BIJUR because they look like they have everything and I have not heard of them before so thank you very much for that.  From the elbow to the tank it looks like it is just simply NPT.  I could be wrong but that is my best guess.  From the elbow to the hose its a compression fitting so I'm going to try to work with the pipe threads first for ease.

Thanks again and I appreciate knowing about a company that has a ton of specialty fittings.


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## wrmiller (Jun 2, 2020)

fishingreg said:


> I'm glad to hear I am not alone although not wishing issues on anyone.  I will get some fitting sizes and start looking for a valve to fit it.  I hate losing all my oil when I am not using it.  Not to mention, its a lot to clean up.



I suspect that the threaded male fitting coming out of the tank is 1/4 NPT, but I'm just guessing.


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## fishingreg (Jun 2, 2020)

wrmiller said:


> I suspect that the threaded male fitting coming out of the tank is 1/4 NPT, but I'm just guessing.


Based on the NPT thread chart they are 1/8" NPT based on OD of the external male threads on the elbow but I will know for sure in a few days when the fitting arrives.  The TPI on 1/8" is 27 and 1/4" is 18 based on the chart and it appears these are 27 TPI as well so it seems to line up pretty well.  This is the elbow which has a male fitting on it going into the black female fitting on the tank.  If I removed the black fitting from the tank it would be larger but I am not sure it is meant to be removed so I left it alone.  I will let you know once I get the valve in though.  It will either be fixed or back to square 1 but my tank is dry so I might as well play now...


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## M.T. Pockets (Jun 3, 2020)

My one shots working fine but have noticed a couple small leaks from the fittings, not enough to warrant fixing. Do you see a puddle of oil getting bigger anywhere? That one shot can hold a lot of oil and it has to go somewhere.


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## fishingreg (Jun 3, 2020)

M.T. Pockets said:


> My one shots working fine but have noticed a couple small leaks from the fittings, not enough to warrant fixing. Do you see a puddle of oil getting bigger anywhere? That one shot can hold a lot of oil and it has to go somewhere.


Oh yes, no problem figuring out where it is going (I just can't see the fitting its coming from), its amazing how much oil that is when you lay it flat in your chip pan.  I have pig mat lining my chip pan after I realized what was going on.  My pan had a solid layer in it, enough that it was dripping out the coolant fitting at the back of the pan and onto the floor.  It dumped its contents within a week or two so there was plenty of oil everywhere, its not a slow leak, its very noticeable.


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## wrmiller (Jun 3, 2020)

Sorry, I meant 1/8", not 1/4.


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## fishingreg (Jun 8, 2020)

So far about all I have found out for sure is it is not 1/8" NPT, its very close and I think the TPI is right on or at max 1 off but the 1/8" NPT part is just about .015 larger in diameter on the majors than 1/8" NPT.  Obviously NPT is tapered but if you take the small end and the large end and measure it, it averages about .015 larger on both ends.  It will go in about a thread and a half but thats it.  The male machine part will thread all the way in on the female NPT part but has a little slop.  So it is probably some metric version of 1/8" NPT.  Its amazing how difficult what should be simple becomes..  I called PM but they unfortunately were no help in figuring out the threads.  If I ever figure it out I will let you know.  I have never looked for a NPT tap but that might be my next step to see if I could just tap the machine part out to 1/8" NPT being that it is so close already.


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## mksj (Jun 8, 2020)

Most likely is is 1/8" BSP which is very common on these fittings, they are very close dimensions the BSP is 28 TPI and the 1/8 NPT is an 27 TPI. My recollection is the BSP taper is slightly different. Most Bijur fitting for some reason seem to BSP or metric.


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## fishingreg (Jun 8, 2020)

mksj said:


> Most likely is is 1/8" BSP which is very common on these fittings, they are very close dimensions the BSP is 28 TPI and the 1/8 NPT is an 27 TPI. My recollection is the BSP taper is slightly different. Most Bijur fitting for some reason seem to BSP or metric.
> 
> View attachment 326840


Thank you very much!!  I bet that is it.  That fits the measurements well and the TPI fits perfect in my 28 TPI gauge.  I know almost nothing about pipe threads so I really appreciate your help and I will get an adapter or valve ordered from them.

Greg


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## fishingreg (Jun 19, 2020)

So if anyone is wondering down the road, mksj is correct as usual, it is 1/8" BPST.  Its a bit tough getting the fitting because Bijur has a pretty large minimum order and that adapter is not something MSC or Grainger had but Bijur was very nice and worked with me to get me a fitting.  I just got a 1/8" BPST male with a 1/8" NPT female so I could put the valve in and was able to use the stock 1/8" BPST male into the 1/8" NPT female on the valve with a little bit of teflon tape.  It just had a slight gap but the tape sealed it up and it on the closed side of the valve so unless I hope the valve to oil it, that fitting has nothing sitting in it really.  So its at least fixed for now.  Thanks for all your help.


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## wrmiller (Jun 19, 2020)

We should have got a few people here to do a batch buy (or whatever you want to call it) as there may have been others here interested. 

Sounds like I may need to remove the tank and make a custom fitting for it.


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## Buffalo21 (Jun 19, 2020)

Earlier this week, I ran a 1/8” npt tap into the 1/8 BSP fitting on the side of the one-shot oil pump, I put on my Rockwell mill.


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## wrmiller (Jun 19, 2020)

Buffalo21 said:


> Earlier this week, I ran a 1/8” npt tap into the 1/8 BSP fitting on the side of the one-shot oil pump, I put on my Rockwell mill.



If I get lazy, I may do exactly that. And add a little Teflon tape.


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## INTJ (Jul 13, 2020)

My 833T one shot leaks oil on the the ways.  Then the oil spills off on to the chip pan.


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