Replacing oil pressure switch

[KWKloeber]

 Stu,

I missing your point about the oil switch on the M 25? Are you saying that you can't get to your oil switch? Or are you saying that  yours is in a different location than where I've said??

Please clarify

[Stu Jackson]

Good question.  I should have said that the inaccessible port port is for the tractor oil pressure gauge sender.  Does THAT clarify it?  My oil pressure switch is where all the M25s have them.

[mregan]

Was at the boat today.  Bought a 15/16" socket to remove the old switch.  Checked the size on the new one first to make sure 15/16" was correct.  First tried to use the 7mm to remove the small screw.  Either it's not a hex head or it's stripped because the 7 didn't fit.  Tried a 6 & 5 and no luck.  By bending back and forth was able to snap the remaining wire which was rusted to the screw.  Went to put on the large socket.  Doesn't fit.  It's a long socket.  Can't tell if it's hitting the engine manifold and won't go on straight or it's too small.  Looking at the switch it's looks a bit different than the Kubota replacement I bought.  The section the socket fits on looks about the same but the small black section in front, where the screw goes in, looks longer than the kubota type.  As a whole it looks bigger than the replacement.  I don't think if it is 15/16" I'd be able to get a short socket on it.  I think the screw in section on the front is too long and wouldn't allow the short socket on enough. Any thoughts?  This thing is driving me nuts.

[KWKloeber]

Possibly a PO installed an aftermarket switch? 
The wire broke off clean, it isn't impeding the socket?

I don't know the aftermarket switches (although there are) that fit that engine.  Though, a PO might have used an NPT thread switch instead of the correct one and you probably would never know it. Maybe it needs a deep socket?

Would sticking a phone in there to snap a pic help ID the switch?

kk

[Stu Jackson]

Ken,

Some years ago, a friend of mine purchased a used M25 engine to put into his Pearson 30 to replace an aging but still working A4.  He was clever: he put it on a dolly in his garage, ran  the inlet cooling water (properly) into a bucket, and the exhaust water went down his driveway!  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I'm on the boat this weekend without my portable hard drive with the pictures of my friend's engine on the dolly in his garage.  I'll post them when I get home on Monday.

Photos of our "untouchable, unseen" port side of the engine.

The oil pressure sensor is run to a hose which goes up a lot higher than I remembered, sneaking into the engine just under the manifold.  The cockpit panel shows the oil pressure gauge (on the right).  Before he put the engine and panel into his boat he removed the ammeter and replaced it with a voltmeter.

[Stu Jackson]

more photos

[mregan]

Went back down tonight with a multitude of sockets, short and deep.  None of them fit.  Thought I was going to get lucky with the 1 1/16" deep socket but no go.  Both the short and long are hitting the bottom of the manifold so they won't on the switch straight.  Going to bring the sockets to work and try to grind one side flat so it will slide under the manifold and fit straight on the switch.  I think if I can get the short socket on fully, it will be past the manifold and I'll be able to get it to work.  If that doesn't work, I can't think of anything else to do.

[KWKloeber]

Stu

Ok, "gauge sender" -- THAT clarifies that part. 
But sorry I must be dense.  Or CRS.  I put your post aside to see your pics and am still mis understanding what you claim about a "tractor" pressure sender (and what it has to do with a C-30 vs a C-34.)

I know of no other oil port on the D850 or D950 block.  Port or starboard or front or back, on a "tractor" engine or on a Kb genset engine.  See the tractor (pic #1) and genset (pic #2) oil ports below.  Same port that I explained to Matt in my post below.




There's no pressure gauge on a Kb tractor, at least that I have heard of.  (Admittedly) I haven't seen all Kb tractor parts manuals, but the half dozen or so that I have shows no pressure gauge -- and I have seen no (tractor) engine manual that has an oil pressure sender. 

The only "other" oil port (and that was on an M-25, not the XP, and not on tractors) is what I described to Matt.  And the remains of it is in your photos.  The bronze (signifying Universal, not Kb tractor) hose leading from the oil port was OEM on M-25s.  The machined block was OEM on the M25s.  Universal unscrewing the oil switch and installing the hose and NPT/JIS threaded block was part of its "marineizing" the Kb D-850 block.  See parts #11 and #20 below (in M-25 manual not Kb tractor manual.)



At some year (unbeknownst to me) Universal discontinued the system (but that's unrelated to a C-30 or a C-34 or a Catalina vs another manufacturer.)  Certainly, engines with a 3" Hx DO NOT have that block.  Saying that he had the remnant of a hanging hose, led me to believe it may be the "oil hose."  If I can see some pics, I might be of more help on that.

Regardless, on the C-34 vs C-30 comparison, if one can get at and switch out the Hx on a C-34, one can get at that OEM M-25 oil switch location -- it was on the SAME bracket (until Universal "moved it back" to the engine block.)  Although I know so little about how C-34 and C-30 engine installations differ, I BET right now Matt wishes he had the OEM M-25 oil block that I described (that you say won't work on your boats) because he'd have the switch out and replaced by now.

Why we have a idiot light/buzzer is because the engine came from Japan with only an oil switch.  It has nothing to do with Seaward/Bristol/CTY engineers, or removing something (for a C-34 install) that's on a tractor.  And I'm not sure how describing the OEM hose is disparaging anyone.  The reason we don't have a pressure sender and gauge comes down to two things 1) Universal didn't provide that option at that point in time (it did later), and 2) the chief Bean Counter didn't pay to add one.  It has nothing to do with the panel designer. manufacturer, or installer.  Fast forward - the shuttle blew up because not because of the designers, but the (political) bean counters who didn't listen to the designers.

Bottom line - I felt an oil gauge was worthwhile to add, and it can be done on the C-34 also. Not quite as easy as 1-2-3, but doable -- I did that this season on three M-25s/XPs.

kk

[KWKloeber]

If that doesn't work, I can't think of anything else to do.

Matt an option is to remove the starter so that the oil switch is visible/accessible.  The starter is 2 bolts. 
"Thin wall" sockets are also made (or they used to be -- but that was years ago (actually decades) that I bought one!)

Interested to see pics of the hose you describe!

Ken

[mregan]

Finally, it's off  .  Got a bunch of long sockets, 15/16, 1" 1/16" 1 1/8".  Cut them down so the socket part was whole but the rest of the socket was cut down so I could fit it under the engine manifold.  When trying to get the socket on the switch it would hit the engine manifold and not sit on the switch straight.  Tried all the sizes, the 1 1/16" fit but would slip a bit so figured the switch might be metric. 
Ended up finding a standard size 26mm socket, couldn't find a deep socket.  I was worried the front part of the switch would stick too far into the socket and prevent the ratchet handle from attaching so I cut down the 1" deep socket and welded it too the 26mm socket.  Tried it out on Sunday and worked like a charm.  I was still only able to turn the ratchet about 1/4 way before the socket would jam against the bottom of the engine manifold.  But turning it 1/4 turn, then removing and repositioning, I was able to get it off pretty quickly.

Replaced the switch with a Kubota 15841-39010 which seems to be the standard replacement switch.  This switch is 15/16".  Still had to use my deep 15/16" socket that I had to cut down to avoid the engine manifold  but it went in smooth.  I might have been able to get a short 15/16" socket with and extension on it to work but I didn't have on with me.
Big thanks to KWKloeber for all his help in my initial wiring confusion and then helping me trouble shoot the switch as the ultimate cause.

First picture is the old switch in the engine block.  Second picture is the old switch removed and the cut down/welded 26mm socket.  The 15/16" socket was cut down the same way.

[KWKloeber]

 Matt,

Congratulations.

It sure looks to me as if your manifold has dropped.    I would seriously look at doing some investigating to see if the top of it lines up correctly, it looks to me like maybe studs had loosened and it's sitting too low?

The switch should simply not be that tight as your photo shows.

The switch is straight Kabota from Japan, so I would ass/u/me that it is a metric size?  It appears to   Have been  the OEM switch.

Ken

[KWKloeber]

Matt

here is a pic (I believe it's the same extracted engine that Stu posted below).  It has the oil hose instead of the switch, but you can clearly see the threaded oil port -- there ***shouldn't be***  the issue that you had with the manifold hitting the socket.  Unless something is really wrong in there.



ken

[mregan]

I'll try to take a better look next time I'm down at the boat.  Although I don't remember the manifold looking tilted or sagging when I'm looking at it.  I hope there nothing wrong with it, I've been using it as a step to get out of the cabin when I have stairs out of the way.

[Catalina007]

Finally, it's off  .  Got a bunch of long sockets, 15/16, 1" 1/16" 1 1/8".  Cut them down so the socket part was whole but the rest of the socket was cut down so I could fit it under the engine manifold.  When trying to get the socket on the switch it would hit the engine manifold and not sit on the switch straight.  Tried all the sizes, the 1 1/16" fit but would slip a bit so figured the switch might be metric. 
Ended up finding a standard size 26mm socket, couldn't find a deep socket.  I was worried the front part of the switch would stick too far into the socket and prevent the ratchet handle from attaching so I cut down the 1" deep socket and welded it too the 26mm socket.  Tried it out on Sunday and worked like a charm.  I was still only able to turn the ratchet about 1/4 way before the socket would jam against the bottom of the engine manifold.  But turning it 1/4 turn, then removing and repositioning, I was able to get it off pretty quickly.

Replaced the switch with a Kubota 15841-39010 which seems to be the standard replacement switch.  This switch is 15/16".  Still had to use my deep 15/16" socket that I had to cut down to avoid the engine manifold  but it went in smooth.  I might have been able to get a short 15/16" socket with and extension on it to work but I didn't have on with me.
Big thanks to KWKloeber for all his help in my initial wiring confusion and then helping me trouble shoot the switch as the ultimate cause.

First picture is the old switch in the engine block.  Second picture is the old switch removed and the cut down/welded 26mm socket.  The 15/16" socket was cut down the same way.

Hi Matt,  I sent you a PM with details. Thanks again!