MZ Govenor

SD diesels were widely available in the US in the 1981-86 Datsun/Nissan 720 pickups, and in Canada through '87 in the D21 pickup.

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dieselscout80
Posts: 27
Joined: 14 years ago
Location: South Carolina

MZ Govenor

#1

Post by dieselscout80 » 11 years ago

All,

Please take a look at this and let me know if you think it will work ok. Note I did not do this.

This guy coverted his MZ govenor to manual control.
http://www.pirate4x4.com/forum/showthre ... 949&page=3




Edited due to my lack of knowledge.

Carey
Diesel Scout

moose60
Posts: 168
Joined: 14 years ago
Location: Seattle WA

#2

Post by moose60 » 11 years ago

Carey,

It looks like it might work well for the guys running turbos. I seem to remember lots of discussion of how to get the pneumatic system to work properly in the presence of boost.

If I was going to go that route, I would try to contact the guy on the other forum and get him to send me dimensions etc. so that I didn't have to re-invent the wheel.

I did see some interesting comments (from other forum members) about not touching the throttle when starting, "It'll flood for sure!" Mine starts best using the procedure outlined in the manual: lotsa throttle till it fires on all four, then back off for a smooth, slow idle. But mine is not a real good cold starter. 20* F if a hard start, but it does it.
Byron

82 Datsun 720 KC SD22

MPG Machine

Bob Drucker
Posts: 8
Joined: 11 years ago
Location: lake co california
Contact:

#3

Post by Bob Drucker » 11 years ago

Boy this thread sure didnt go anywhere. Well, I just did this manual conersion on a sd22 and added a volvo turbo and inter- cooler, just waiting to complete the adapter and install in my LR. End of summer should have a report on if and how well this works!....bob
roverdiesel

Nissan_Ranger
Posts: 264
Joined: 13 years ago
Location: Canada

#4

Post by Nissan_Ranger » 11 years ago

Be sure to post some pictures as well. I look forward to them!
The old 'six gun' was as popular as the cell phone in its time and just as annoying when it went off in the Theater.

User avatar
Knucklehead
Posts: 148
Joined: 14 years ago
Location: Phoenix

#5

Post by Knucklehead » 11 years ago

Very interested in how this works for you Bob. I would have done this, but with the back off, holding the rack by hand, I couldn't make the thing idle. On the factory governors (any of them), the rack movement is a dynamic combination of rpm and load. If you take the front cap off and watch the end of the rod at an idle, it is not sitting still, but quicly moving back and forth like a sewing machine. I don't know that it can't be done, but I sure am interested in how.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

pbknowles
Posts: 95
Joined: 14 years ago
Location: Illinois, USA

#6

Post by pbknowles » 10 years ago

I recently converted my SD from the MZ governor to the RSV (tractor) type. It was a bit of a chore and I am not sure how happy I am with the results. After completing this exercise, I do not think that any variation of the RSU (automotive) type can be made to fit. I can post pics if there is any interest. My intent was simply to get rid of the throttle body in preparation for a turbo.
SD22 powered '85 Chevy S-10

Bob Drucker
Posts: 8
Joined: 11 years ago
Location: lake co california
Contact:

MZ governer

#7

Post by Bob Drucker » 10 years ago

By all means lets see what you have done with thw MZ to tracter swap. Lots-o-pics please and explanations......Bob
roverdiesel

pbknowles
Posts: 95
Joined: 14 years ago
Location: Illinois, USA

#8

Post by pbknowles » 10 years ago

OK, I will need to learn how to post the pics, but here goes. I bought a couple of other "A" size pumps with RSV governors off of eBay cheap. The first one was a two cylinder pump from an Isuzu marine engine. At first I thought I could use this governor, but it was really old and also since it was made for a hand throttle, didn't have a shutdown lever. This could have been overcome by using a throttle kicker solenoid, but after removing it from the pump I found that the pump itself was set up with a ball bearing to support the governor end of the cam, whereas the SD pump uses a tapered roller bearing. Again, this could have been overcome, but would have involved disassembling the fuel section of the pump which I did not want to disturb. A photo of the governor end of this pump:
Image
Also, this pump did not receive its oil from the engine like the SD pump does. There was a small dipstick for the pump, and a small dipstick for the governor, and the two cavities were separated by a lip seal. Of course the drive end of the pump shaft was also sealed by a lip seal.

The second pump I had was a Zexel, not a Kikki, but since they are all built under license from Bosch this is not a problem. This pump would have pumped too much fuel for the SD as it has 9.5mm plungers (stock SD is 6mm), and the drive end interface would have required machining, so using the pump complete was not an option. This pump had the correct bearing configuration and a shutdown lever, so I decided to liberate it's governor and give it a try using a spare SD pump I had. While the Zexel pump was set up to receive its lube oil from the engine, it was not exactly the same as the setup on the SD pump. The SD pump has a small external oil line on the back (block) side that taps oil off the main pump gallery and feeds the governor. Then there is a small rubber impeller pump that moves the "governor" oil back up front where it overflows into the gearcase on the engine. The Zexel pump just splash lubed the governor, via rotating the overboard drain holes in the drive end plate to the top and again applying a lip seal to the shaft. This drives the oil level in the pump higher than it would be in the SD version. I debated which approach to use, but in the end simply machined off all the un-needed ears on the back side of the governor and added a drilled and tapped hole for the little oil line.See pics:


The zexel pump also had a long bulbous cover over the full load stop (bottom most) adjust screw that seemed to serve no purpose and would not clear the SD's oil cooler. I removed this cover and replaced it with the flat cover off the Isuzu pump, and shortened the adjustment screw accordingly. Also spot faced the Isuzu cover on the mill to provide a sealing surface for the copper washer. I kept the little dipstick so I could see that the governor was getting lubed.

Of course had to fabricate a linkage and cable for the shutdown lever, made from old Mercedes W123 cruise control linkage and a "throttle" cable which came from a Chevy Cavalier since it matched up with the hole in the firewall and the throttle pedal in my S10.

Even with all of this the pump still won't clear the oil filter, which I relocated to the place where the Nissan pump control motor once resided.

Notes on pump #'s
SD Pump is PES4A60XXXXRXXXX
PE = Inline Pump
S = Flange mount
4 = # of high pressure outlets
A = Pump size
60 = Plunger diameter in 1/10 mm
R = Direction of rotation
The rest aren't important.

Notes on RSV governor numbers
RS = Tractor type
V = Variable speeed governing
350 = low idle speed (350 PUMP rpm, 700 engine RPM)
1300 = full oad rated speed (1300 pump rpm, 2600 engine rpm)
SD22 powered '85 Chevy S-10

pbknowles
Posts: 95
Joined: 14 years ago
Location: Illinois, USA

#9

Post by pbknowles » 10 years ago

Finally got a day off by being sick! Got pics to work....but here goes. I bought a couple of other "A" size pumps with RSV governors off of eBay cheap. The first one was a two cylinder pump from an Isuzu marine engine. At first I thought I could use this governor, but it was really old and also since it was made for a hand throttle, didn't have a shutdown lever. This could have been overcome by using a throttle kicker solenoid, but after removing it from the pump I found that the pump itself was set up with a ball bearing to support the governor end of the cam, whereas the SD pump uses a tapered roller bearing. Again, this could have been overcome, but would have involved disassembling the fuel section of the pump which I did not want to disturb. A photo of the governor end of this pump:
http://home.comcast.net/~pbknowles/pwpi ... CN1992.jpg

Also, this pump did not receive its oil from the engine like the SD pump does. There was a small dipstick for the pump, and a small dipstick for the governor, and the two cavities were separated by a lip seal. Of course the drive end of the pump shaft was also sealed by a lip seal.
http://home.comcast.net/~pbknowles/pwpi ... CN1995.jpg

The second pump I had was a Zexel, not a Kikki, but since they are all built under license from Bosch this is not a problem. This pump would have pumped too much fuel for the SD as it has 9.5mm plungers (stock SD is 6mm), and the drive end interface would have required machining, so using the pump complete was not an option. This pump had the correct bearing configuration and a shutdown lever, so I decided to liberate it's governor and give it a try using a spare SD pump I had. While the Zexel pump was set up to receive its lube oil from the engine, it was not exactly the same as the setup on the SD pump. The SD pump has a small external oil line on the back (block) side that taps oil off the main pump gallery and feeds the governor.

Then there is a small rubber impeller pump that moves the "governor" oil back up front where it overflows into the gearcase on the engine.
http://home.comcast.net/~pbknowles/pwpi ... CN2001.jpg

The Zexel pump just splash lubed the governor, via rotating the overboard drain holes in the drive end plate to the top and again applying a lip seal to the shaft.
Zexel: http://home.comcast.net/~pbknowles/pwpi ... CN1997.jpg
SD: http://home.comcast.net/~pbknowles/pwpi ... CN1999.jpg

This drives the oil level in the pump higher than it would be in the SD version. I debated which approach to use, but in the end simply machined off all the un-needed ears on the back side of the governor and added a drilled and tapped hole for the little oil line.See pics:
http://home.comcast.net/~pbknowles/pwpi ... CN2000.jpg


The zexel pump also had a long bulbous cover over the full load stop (bottom most) adjust screw that seemed to serve no purpose and would not clear the SD's oil cooler. I removed this cover and replaced it with the flat cover off the Isuzu pump, and shortened the adjustment screw accordingly. Also spot faced the Isuzu cover on the mill to provide a sealing surface for the copper washer. I kept the little dipstick so I could see that the governor was getting lubed.
http://home.comcast.net/~pbknowles/pwpi ... CN1998.jpg

Of course had to fabricate a linkage and cable for the shutdown lever, made from old Mercedes W123 cruise control linkage and a "throttle" cable which came from a Chevy Cavalier since it matched up with the hole in the firewall and the throttle pedal in my S10.
http://home.comcast.net/~pbknowles/pwpi ... CN2017.jpg

Even with all of this the pump still won't clear the oil filter, which I relocated to the place where the Nissan pump control motor once resided. You can just see the red hoses going to the relocated filter:
http://home.comcast.net/~pbknowles/pwpi ... CN2016.jpg

Notes on pump #'s
SD Pump is PES4A60XXXXRXXXX
PE = Inline Pump
S = Flange mount
4 = # of high pressure outlets
A = Pump size
60 = Plunger diameter in 1/10 mm
R = Direction of rotation
The rest aren't important.

Notes on RSV governor numbers
RS = Tractor type
V = Variable speeed governing
350 = low idle speed (350 PUMP rpm, 700 engine RPM)
1300 = full oad rated speed (1300 pump rpm, 2600 engine rpm)

The RSV governor is not that great for road use. You get used to it, but it is definitely weird, as a given pedal position now corresponds to a desired RPM. You end up holding it on the floor as you run up through the gears, (except when shifting of course) then backing off to a position that gives you the speed you want. After that it acts like it is on cruise control as it will increase engine torque in response to load (hills). There is a lot more torque available at lower rpm's than with the pneumatic setup however. I have not noted any change in fuel mileage.

Next step is to take it all apart again and try to convert the RSV governor to a type RS.
Last edited by pbknowles 10 years ago, edited 2 times in total.
SD22 powered '85 Chevy S-10

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