Home » Public Forums » GMCnet » "frozen" Low Oil Pressure sensor removal
| "frozen" Low Oil Pressure sensor removal [message #345689] |
Wed, 24 July 2019 21:24  |
Deb
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
|
Senior Member |
|
|
I have spent the past few days replacing the gaskets on my Onan oil filter bracket. 45 years old, (like they were welded on!) the one against the block was blowing oil. Many Thanks to Jim Miller for patiently walking me through this one.
While I have this bracket out, I want to replace the LOP sensor. It is on a 90 degree fitting so if and when it does go, it will be a pain to get at. However, like the rest of her, this sensor has been in place for the life of the generator and was absolutely caked with old oil and crud like evrything else in that area, because of the leaking gasket.
I have tried brake cleaner, paint remover, and was soaking in Goof-Off for about 4 hours till now. The 90 degree fitting will turn in the bracket, but the sensor itself will not budge in the fitting. It's nice and clean  but won't move. I now have it sitting on the bench with some penetrating oil hopefully running down along the threads, and perhaps, by tomorrow, it may shift. Next attempt is vice grips and the bench vice! But I don't want to break the thing - I am heading out this weekend.
Anyone have a great way of convincing a decidedly reluctant set of 45 year old threads to let go!?
Deb McWade
Logan Lake, BC, CAN
GMC Alumnus
It's Bigger on the Inside!
[Updated on: Wed, 24 July 2019 21:25] Report message to a moderator |
|
|
|
| Re: "frozen" Low Oil Pressure sensor removal [message #345694 is a reply to message #345689] |
Wed, 24 July 2019 23:22  |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
My next suggestion is do not mess with it unless you have a new one available. The threaded end of that thing is hollow and not very strong. Heat will always do it but you will most likely burn up the insides doing it.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
| Re: "frozen" Low Oil Pressure sensor removal [message #345695 is a reply to message #345694] |
Thu, 25 July 2019 00:13 |
Deb
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
|
Senior Member |
|
|
Hi Ken. I have a new sensor. I was hoping to get it in there while I have it all apart instead of waiting for it to pack it in. But if the penetrating oil hasn't done anything by morning, I will put it back together as is and deal with it if it does quit at some point in the future.
Deb McWade
Logan Lake, BC, CAN
GMC Alumnus
It's Bigger on the Inside!
|
|
|
|
| Re: "frozen" Low Oil Pressure sensor removal [message #345696 is a reply to message #345695] |
Thu, 25 July 2019 02:46 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
What I am afraid of is those sensors are not usually very mechanically strong. It is easy to twist one off. That is why I suggested that you have a spare available before start the project.
I had one leaking on an Olds 350 engine and bought a spare, but I never installed it. The sensor decided to blow completely apart on US 6 between Ely and Tonopah, NV. I was about 80 miles in either direction to civilization. It had blown oil everywhere. I tried to remove it with the proper socket and broke it off. After About 2.5 hours a rancher / farmer in a PU truck stopped and happened to have easy outs and some oil. He also had a large propane powered soldering iron and penetrating oil. We got it out in about 30 minutes with heat and his easy outs. With a couple quarts of his oil installed I was on my way with the new sender installed.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
| Re: "frozen" Low Oil Pressure sensor removal [message #345701 is a reply to message #345696] |
Thu, 25 July 2019 08:17 |
C Boyd
Messages: 2629
Registered: April 2006
Karma: 18
|
Senior Member |
|
|
I also had a bad leak on my 6000 Onan oil pressure switch. After removing the side cover so I could see it I found a new sending unit and a shinny new 45* fitting. The leak was where the 45* fitting was screwed in the oil filter adapter and I could turn with my fingers enough for sensor to hit the engine. After removing I found the fitting the PO put in had machine threads on the male end and had tapered threads on the female end. In the manual it did not show a fitting. I left the fitting off and screwed the sensor directly into the oil filter housing. It was close and a socket would not work straight on so I carefully used pliers to tighten and no leaks.
C. Boyd
76 Crestmont
East Tennessee
|
|
|
|
|
|
|
|
| Re: [GMCnet] "frozen" Low Oil Pressure sensor removal [message #345706 is a reply to message #345703] |
Thu, 25 July 2019 09:23 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
|
Senior Member |
|
|
Gee Jim I now know there is Mrs Garmon.
On Thu, Jul 25, 2019 at 6:37 AM James Hupy via Gmclist <
gmclist@list.gmcnet.org> wrote:
> If it ain't broke, fix it 'till it is. Another of those "Murphy's gonna get
> you if you let him" projects.
> Did you know that Murphy got married? Wife's maiden name was Ms.
> Garmin. She is in charge of all navigation errors.
> Jim Hupy
> Salem, Oregon
>
> On Thu, Jul 25, 2019, 6:30 AM Justin Brady via Gmclist gmclist@list.gmcnet.org> wrote:
>
>> Easiest solution may be to just get a new fitting as well.
>> Should be a standard size, usually available in brass at lowes.
>>
>> It may be something special though I'm not familiar with it.
>> --
>> Justin Brady
>> http://www.thegmcrv.com/
>> 1976 Palm Beach 455
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
|
|
|
|
| Re: [GMCnet] "frozen" Low Oil Pressure sensor removal [message #345707 is a reply to message #345706] |
Thu, 25 July 2019 10:39 |
Deb
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
|
Senior Member |
|
|
I am heading out this morning to get a new brass elbow as well. I was also concerned about something shearing off, snapping or otherwise bust in this whole process. Maybe the reason for the elbow was so you could get a socket on it if you wanted to, or Jim Miller thought it might be to make that top nut accessible (the original sensor is much larger and would block that top nut somewhat). Isn't in the parts manual so maybe an afterthought or change in later years. The replacement sensor (from Jim K) is smaller in diameter so could actually go straight into the bracket without the elbow and still leave everything relatively accessible. Wiring reaches as well.
Right now my concern is that, now that all of the grunge is cleaned off, the elbow turns quite easily in the bracket and I am concerned that it will start to leak. I can finger-tighten it about 1/8 turn and it starts to firm up. Could go farther but then I'm probably going to cause problems - a brass fitting into an aluminum bracket - something will probably strip on me! But I think there is a high chance that the vibration will just cause it to drop down and loosen again. I have a new sensor and I will have a new elbow. If I can't get things to move this morning, my current thought is that I can either cut the old sensor off with my wee dremel, unscrew the elbow and replace both, or try it with just the sensor directly into the bracket. Advantage of the direct connection would be that I wouldn't have gravity working against me with the elbow staying seated.
Or just use a little thread-lock at the elbow at it's loosest point and give it that 1/8 - 1/4 turn and see how that goes.
Deb McWade
Logan Lake, BC, CAN
GMC Alumnus
It's Bigger on the Inside!
|
|
|
|
| Re: [GMCnet] "frozen" Low Oil Pressure sensor removal [message #345708 is a reply to message #345707] |
Thu, 25 July 2019 11:00 |
Emery Stora
Messages: 959
Registered: January 2011
Karma: 4
|
Senior Member |
|
|
Be sure to check if he fitting is tapered pipe thread or a straight machine thread. They are the same diameter and same threads per inch. People often put one or the other into a mismatched thread and it will cause jamming or leaks.
Emery Stora
77 Kingsley
Frederick, CO
> On Jul 25, 2019, at 9:39 AM, Deb McWade via Gmclist wrote:
>
> I am heading out this morning to get a new brass elbow as well. I was also concerned about something shearing off, snapping or otherwise bust in this
> whole process. Maybe the reason for the elbow was so you could get a socket on it if you wanted to, or Jim Miller thought it might be to make that
> top nut accessible (the original sensor is much larger and would block that top nut somewhat). Isn't in the parts manual so maybe an afterthought or
> change in later years. The replacement sensor (from Jim K) is smaller in diameter so could actually go straight into the bracket without the elbow
> and still leave everything relatively accessible. Wiring reaches as well.
>
> Right now my concern is that, now that all of the grunge is cleaned off, the elbow turns quite easily in the bracket and I am concerned that it will
> start to leak. I can finger-tighten it about 1/8 turn and it starts to firm up. Could go farther but then I'm probably going to cause problems - a
> brass fitting into an aluminum bracket - something will probably strip on me! But I think there is a high chance that the vibration will just cause
> it to drop down and loosen again. I have a new sensor and I will have a new elbow. If I can't get things to move this morning, my current thought is
> that I can either cut the old sensor off with my wee dremel, unscrew the elbow and replace both, or try it with just the sensor directly into the
> bracket. Advantage of the direct connection would be that I wouldn't have gravity working against me with the elbow staying seated.
>
> Or just use a little thread-lock at the elbow at it's loosest point and give it that 1/8 - 1/4 turn and see how that goes.
> --
> Deb McWade
> Logan Lake, BC, CAN
> "Li'l Sister"
> '77 Kingsley, 403, EBL EFI;
> TZE167V101404
> It's Bigger on the Inside!
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
|
|
|
|
|
|
| Re: [GMCnet] "frozen" Low Oil Pressure sensor removal [message #345730 is a reply to message #345709] |
Thu, 25 July 2019 16:04 |
Deb
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
|
Senior Member |
|
|
Couldn't budge the sensor and since the connection between the elbow and the bracket was loose and really not reliable (after removing all of the crap holding it all in place), I opted to remove the sensor (using my little dremel wheel), discard the elbow and just install it directly to the bracket, per Jim M advice. Tightened everything up as best i could, fired her up and watched as oil blew ALL over! Leaking some from the sensor, and along the gasket bolts. Re-torqued everything - maybe the initial start-up shaking bumped things around, lined them up and therefore everything was loose. Once I tightened the sensor, and both ends of the bracket (bottom nut is impossible without the flex-head wrench and a pair of vice grips for leverage) things look good.
Waiting for oil that blew into the flywheel housing to dissipate (ie drip) and will go back to re-check in an hour.
So far, looks good. Fingers crossed. Not getting out of my grimy jeans till I'm happy!
When I looked at the threaded end of the old sensor left in the elbow, I can see why it wouldn't move - it had been thread-locked.
Deb McWade
Logan Lake, BC, CAN
GMC Alumnus
It's Bigger on the Inside!
|
|
|
|
Goto Forum:
Current Time: Sun Jan 19 02:35:03 CST 2025
Total time taken to generate the page: 0.04209 seconds
|
GMCforum
Search
Help
Register
Login
Home
I think I met her on my way to Wallowa last fall.