D750 Kubota Engine - what is this part?

[6mmbr]

I am replacing a D750 engine in my B7100. My replacement engine has this geared cable drive in the front (cable is cut off shortly after connection). Is this a cable to an RPM gauge or something else?

Thanks for help.

 

[Joe H]

Or an hour meter.

Joe H

 

[leonz]

Doesn't your tractor have a tachometer and an original cable identical to this?

 

[GPintheMitten]

I have a 750 engine in my Kubota b6200. I won't be home until late Thursday. But I think it goes to the hour meter. I recall seeing a similar cable on the hour meter on the dash.

 

[kuboman]

I am replacing a D750 engine in my B7100. My replacement engine has this geared cable drive in the front (cable is cut off shortly after connection). Is this a cable to an RPM gauge or something else?

Thanks for help.

Tach drive and most tachs have a hour meter too.

 

[6mmbr]

My B7100 tractor has an electric hour meter.

Thanks for the reply.

I don't see any benefit from a tachometer on my little tractor to me so I will just cap it to keep the dust out.



On a related question, anybody ever adapt "T" fittings to have the oil switch as well as an oil pressure gauge on these engines?

 

[GPintheMitten]

My B7100 tractor has an electric hour meter.

Thanks for the reply.

I don't see any benefit from a tachometer on my little tractor to me so I will just cap it to keep the dust out.

On a related question, anybody ever adapt "T" fittings to have the oil switch as well as an oil pressure gauge on these engines?

What is an oil switch? Maybe you mean oil pressure guage?

 

[6mmbr]

I believe it is the low oil pressure engine kill switch.

Kubota refers to it as "Switch oil" part# 15841-39010. See page 1 Kubota B7100HST parts manual, or Kubota workshop manual page A 5-2, under checking engine oil pressure.

Although, it is a 'head scratcher' for me, that in order to check the oil pressure you disconnect the switch and plug in the pressure gauge then start the engine. Soooo with switch disconnected the engine will start. Sooo if the switch is bad and not working, will the engine start?

 

[JOHNINMA]

On my B5200 it operates the combination rpm/hour meter. It comes in handy for keeping track of run time for maintenance.

 

[j t huskins]

My B7100 tractor has an electric hour meter.

Thanks for the reply.

I don't see any benefit from a tachometer on my little tractor to me so I will just cap it to keep the dust out.



On a related question, anybody ever adapt "T" fittings to have the oil switch as well as an oil pressure gauge on these engines?

Yea I am doing this during my rebuild to hook a manual OP gauge. As for as I can tell on my year model the factory sending unit only controls a low oil pressure light on the dash which will not shut the engine off. The only engine kill method is the compression release. As far as the cable shown in your picture I would guess that it was a tach cable .

 

[j t huskins]

Have you pulled the head off of the engine that is leaking oil yet? I finished ordering all of the gaskets for my rebuild yesterday and found out from a Kubota rep who happened to be at my local dealership that the O ring I mentioned in my rebuild post is a special one made for this application to seal the pressure port at the head and if any other O ring is used it will leak.

 

[6mmbr]

Yes thanks.

I see that it's just an "idiot" light; not kill switch.

So I am going to put in an oil pressure gauge and get rid of the idiot light.
I think I will put the water temp gauge in where the current hour meter is. I am going to put the oil pressure gauge in where the glow plug instruction sticker is. I plan to put in a Datel voltmeter probably where the hazard switch is and put in a rectangular hour meter somewhere. In other words, just change the whole dash around. I'm going for 'functional' not 'original'. I'll post some pictures once I get it configured. Now I gotta go figure out where my plasma cutter is.....

ps JT: following your rebuild thread with interest!

 

[6mmbr]

No, have not done anything with old engine yet. Got a "runner" from a supplier and am going to get it switched in. Will tear down the old and rebuild if possible for spare when get this project done. It has a lot of JB Weld in that corner for a reason I suspect.

I have to switch flywheels and put on different front crank pulley on new engine. I suspect it probably came out of bobcat so had no clutch. Has a front oil pan drain so I have to switch that too. It was probably horizontally mounted.

I take note of the special "O" ring you mention. Hopefully can plug a "homemade" fitting in there for the pressure takeoff that won't leak.

 

[leonz]

Yea I am doing this during my rebuild to hook a manual OP gauge. As for as I can tell on my year model the factory sending unit only controls a low oil pressure light on the dash which will not shut the engine off. The only engine kill method is the compression release. As far as the cable shown in your picture I would guess that it was a tach cable .

I looove compression release, it is so numb, dumb, and stupid and it always works(unless the injection pump decides to run away that is and then its time to stuff rags in the air intake and hope it does not start consuming the oil in the sump)HAHA.

 

[j t huskins]

Yes thanks.

I see that it's just an "idiot" light; not kill switch.

So I am going to put in an oil pressure gauge and get rid of the idiot light.
I think I will put the water temp gauge in where the current hour meter is. I am going to put the oil pressure gauge in where the glow plug instruction sticker is. I plan to put in a Datel voltmeter probably where the hazard switch is and put in a rectangular hour meter somewhere. In other words, just change the whole dash around. I'm going for 'functional' not 'original'. I'll post some pictures once I get it configured. Now I gotta go figure out where my plasma cutter is.....

ps JT: following your rebuild thread with interest!

Sounds like you have a plan. I looked at mounting options the same way you have but I wanted to keep it as original as possible so I am using a dual face mount under the dash which will be a little harder to see at a quick glance but will work. You won't have any problem using a nipple or tee to tap into the sending unit port.The O ring that I spoke of is between the head and deck surface and is part of the head gasket sealing. Maybe someone just smeared JB on there hoping for a quick fix. If the hydro dosen' have a temp monitoring system maybe now would be a good time to invent one.

 

[6mmbr]

Hmmm...

Free case suction oil heading towards the cooler would be the easiest. Tap into the hose (part# 66204-36220) would be straight forward but would this be the best information?

I dunno...

 

[6mmbr]

Probably gonna need one of these to hook up oil pressure line in place of oil switch:

Auto Meter 2269 1/8" NPT (female) to 1/8" BSPT (male) Oil Pressure Metric Adapter

or other manufacture. I have had this problem before working on my Kubota excavator - they use crazy Japanese Industrial Standard threads, which are similar to British Standard. USA is typically using National Pipe Thread Fine (1/8x27), or Army Navy (AN). If go buy oil pressure gauge at auto zone (to match the water temp gauge) it won't fit without it.

An expensive little piece of brass ($14.50 on Amazon).

or may able to use this one:
Sunpro CP7573 Metric Adaptor Kit by Sunpro
which is cheaper, but don't know what is in it.

j

 

[j t huskins]

This is what I purchased at a local auto parts store. NAPA had the same pieces but they were priced higher. The female tee was 2.84 and the nipples were 1.20 each. I just took my sending unit to the store and matched up fittings that worked. Hate to say it but I don't even know what thread it is.

 

[955Lincoln]

1/4" pipe thread.

 

[6mmbr]

1/4" pipe thread.

sorry, I am confused by that (easy to do, ask my wife).

The B7100 block appears to be tapped for Japanese Industrial Standard (compatible with British Standard Pipe Thread) 1/8x28 taper.

1/4" pipe thread is HUGE compared to 1/8 and has a thread pitch of 18. In metric it is 1/4x19. One would have to drill out the block to get that in as far as I can see.

Anyway, I have wedged in many 1/8x27 NPTF into 1/8x28 BSPT using some teflon tape and it can work. Hopefully will in your case. In my case, the nipple I have for my pressure tubing was parallel and the block appears to a true taper so I could not even get it started. I hope you have better luck!!

I found this too in my reference book:

BSPT (British Standard Pipe Thread) is similar to NPT except for one important difference. The angle across the flanks of threads (if you sliced the fitting in half long-ways and measured the angle from root to crest to root) is 55 degrees instead of 60 degrees as it is for NPT. Thus an NPT male will fit into a BSPT fitting or vice versa but they will not seal. This is a popular fitting in China and Japan but is very rarely used in North America unless the equipment to which it is attached was imported. Thread sealant is needed to seal the male and female fitting together.

..and just for thinking about it, here is what is probably used for the hydraulic connections:

BSPP (British Standard Parallel Pipe) is most popular in the UK, Europe, Asia, Australia, New Zealand and South Africa. It is a parallel thread fitting that uses a bonded seal ring to do the sealing. This bonded ring seal is sandwiched in-between a shoulder on the male fitting and the face of the female fitting and is squeezed in place. BSPP pressure gauges have a longer male thread and use a copper crush washer that is squeezed in between the bottom of the male fitting and the bottom of the female BSPP hole forming a pressure tight seal. No thread sealant is needed to form a seal.