* Pneumatic Governor Diaphragm *

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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EvergreenSD
Posts: 70
Joined: 18 years ago
Location: Eugene, OR

#31

Post by EvergreenSD »

Yesterday I went out and bought myself a MightyVac vacuum guage/pump. I replaced the 4 vacuum lines from the intake to the diaphram. Then I put the guage on the venturi vaccum side of the diaphram housing.
Short answer: it's not leaking. It took over two minutes to bleed down from 20 inHg to 15 inHg. Some of this leakage was undoubtably in the connections between the guage and the truck. I don't believe there is anyway that this would be effecting a vacuum signal. I did just notice Knucklhead's comment about a line teeing off the oil cooler and I will check this but I really don't think that's going to be my answer either.
I am getting frustrated here. What should I try next, verifying pump timing? Is that likely to cause a noticeable problem only when cold? If so, would you theorize that it is retarded or advanced? Any other theories?
'82 SD22 720 Kingcab with flatbed
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Knucklehead
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Location: Phoenix

#32

Post by Knucklehead »

Yes, it is possible that retarded timing will cause those problems when cold, especially if the smoke is white. When the variable timing mechanism on my Cummins malfunctions and leaves the timing retarded it acts just like that until it warms up. But I'm not saying that's your problem.

Have you had your injectors checked lately? Maybe it's a combination of both things?

Later-

Oh hell, I just read up on all the stuff I missed on the cold start thread.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model
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philip
Deceased
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Location: Southern California, USA

#33

Post by philip »

EvergreenSD wrote:SNIP I did just notice Knucklhead's comment about a line teeing off the oil cooler and I will check this. SNIP I am getting frustrated here. What should I try next, verifying pump timing?
YES.
EvergreenSD wrote: Is that likely to cause a noticeable problem only when cold?
Depends very much on the actual cetane rating of your fuel. Cold engine combustion knock
-Philip
Passed 08May2008
My friend, you are missed . . .

1982 Datsun 720KC SD-22

"Im slow and I'm ahead of you"
mbehensky
Posts: 4
Joined: 15 years ago
Location: Soquel, CA

Southwest Diesel website

#34

Post by mbehensky »

Hi, everybody-

http://www.southwestdiesel.com doesn't seem to work now (it is one of those annoying "parking" pages). After looking at the invoice, I tried http://www.swdiesel.com and that works fine.
1981 Datsun 2wd pickup
1982 Mercedes 240D
1987 Mercedes 300D wagon (cracked head)
1981 Mercedes 300D 2.5 Turbo (bad transmission)
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ecomike
Posts: 242
Joined: 18 years ago
Location: Houston Tx

#35

Post by ecomike »

FWIW after 4 years, mine is still working, with the vacuum pump oil.
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.
Nissan_Ranger
Posts: 270
Joined: 17 years ago
Location: Canada

#36

Post by Nissan_Ranger »

ecomike wrote:FWIW after 4 years, mine is still working, with the vacuum pump oil.
Likewise since 2004 with powersteering fluid...

N_R
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.
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ecomike
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Joined: 18 years ago
Location: Houston Tx

#37

Post by ecomike »

Which power steering fluid? The clear stuff, or the red Tranny fluid version?
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.
charmalu
Posts: 166
Joined: 13 years ago
Location: Soquel, Calif

#38

Post by charmalu »

I just re-read through this thread again. as Phill mentioned in the first thread about Cod-liver oil.

When I first bough the 82 back in 81 brand new, I purchased a FSM from the dealer. I read about using a Diaphram oil. so I go to the dealer, and the 2 goof balls behind the counter really had no idea what I was talking about. so they searched a little, and came up with using Cod-Liver oil.

I buy some and stick it in. I did notice later that what I drippled on the outside of the IP was thick and sticky later on. that can`t be good, whats it doing inside the IP :?: :shock:

I purchaed a book "How to Convert Your Car, Van, or Pickup to Diesel" By Paul Dempsey ISBN 0-8306-8968-0 Tab Books # 968 first printing April 78 third print April 80 so may not be around now.

Chap 5 The Fuel system PG 132 he states:

"The Leather Diaphragm may grow stiff in service and give erratic respone. It can usually be salvaged bt applicaton of Neats Foot Oil, which may be sold at engine outlets as "Diphragm Oil". New gaskets which have been coated with liquid Silicone or some other trustworty sealer must be used whenever the Govenor unit is disassembled."

I have use Neats Foot Oil over the years w/o any problems. However now that Iam approaching 30 yrs of service, Iam thinking maybe I need to replace the Diaphragm. runs fine on the flats, but hitting a hill looses power.


Charlie
82 Datsun KC 483K lost #2 cyl blowing blue smoke :cry:
83 Nissan LB 134K SD-25 as of 10-21-13
78 240D Mercedes $300 Parts?
80 240D 360K
80 240D Parts? $750
82 240D Parts? $440
84 300SD 270K
85 300D 363K
86 Ford F250 6.9 Diesel 221K
Nissan_Ranger
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Joined: 17 years ago
Location: Canada

#39

Post by Nissan_Ranger »

ecomike wrote:Which power steering fluid? The clear stuff, or the red Tranny fluid version?
The clear light hydraulic type. I forget which variety.
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.
Nissan_Ranger
Posts: 270
Joined: 17 years ago
Location: Canada

#40

Post by Nissan_Ranger »

charmalu wrote: SNIP... However now that Iam approaching 30 yrs of service, Iam thinking maybe I need to replace the Diaphragm. runs fine on the flats, but hitting a hill looses power.
Charlie
I don't suppose that the thirty years of good service from the engine might be slowing it down some on hills....?

Andy
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.
Dale
Posts: 19
Joined: 11 years ago

#41

Post by Dale »

swdiesel emailed me back, says they dont have the diaphragm in stock anymore due to bosch discontinuing the part. They are calling other distributers looking for more inventory but it's not looking good.

Anyone have a lead? My engine's surging :P
Nissan_Ranger
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Joined: 17 years ago
Location: Canada

#42

Post by Nissan_Ranger »

Make one?
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.
varmint
Posts: 1
Joined: 11 years ago

Zexel diaphragm

#43

Post by varmint »

New member - first post here.

I've been having lots of black smoke and no power on hills for about a year. The engine has 190K on it. I've tried a few things, then ran across this thread last night.

I also called Southwest Diesel and was told the part is obsolete and that they sold the last 5 to someone about a month ago - someone stocking up I guess.
They helpfully gave me a Bosch cross reference 9421-610-043. Google gave me a couple of Asian and Italian distributors for the Zexel, and nothing for the Bosch.

I wrote the Indian distributor - the only thing I ever ordered from overseas was a CD through Amazon, so we'll see how this goes.
82 720 SD22 longbed
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ecomike
Posts: 242
Joined: 18 years ago
Location: Houston Tx

#44

Post by ecomike »

Did you ever find a source for the diaphragm? If so where?
Regards,

Mike

1985 Jeep Cherokee Pioneer, 2WD, retrofitted with SD-22 & 5 spd manual trans, a 4X4 Gas Wagoneer ltd. (XJ) Jeep, 4.0 L w/ AW4 auto, and now 2 spare 2wd Jeeps, 87 & 89.
nakturk
Posts: 5
Joined: 11 years ago
Location: Ankara / TR

#45

Post by nakturk »

I'm also in search of that diaphragm, couldn't find one yet, but found Denso and Nissan codes for it, posting for reference.

9421610043 Bosch
19225 76200 Nissan
090580 0031 Denso
155020 7920 Zexel
1986 Double Cab 4x4 SD25
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