Sd22 Runaway and diaphragm hunt

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.

Moderators: plenzen, Nissan_Ranger

handcannon
Posts: 57
Joined: 4 years ago

Re: Sd22 Runaway and diaphragm hunt

#16

Post by handcannon » 3 years ago

A year ago I got a spare diaphragm from Oregon Fuel Injection, 4036 W. 1st Ave, Eugene, Oregon. I talked to Paul in parts dept at 541-485-1434, oregonfuelinjection.com. It was #155020-7920, which according to what I have in my notes is a Zexel number. At that time it was $36.10 plus the freight. It was shipped in from somewhere back east, and then shipped to me by UPS. I am about 45 miles away from Eugene, and though UPS wasn't cheap it was cheaper than going to Eugene and back for me.

I haven't opened up the IP to check if that is the correct diaphragm, but it looks like it is correct.

It is possible that you might find a diesel repair (injection pump) facility closer to you and maybe save a little bit on shipping.

I hope this info/number helps you.

Don

plenzen
Posts: 868
Joined: 13 years ago
Location: Cochrane Alberta Canada

Re: Sd22 Runaway and diaphragm hunt

#17

Post by plenzen » 3 years ago

Have a read through here

http://nissandiesel.dyndns.org/viewtopi ... 3&start=60

Go down to post number 72 and perhaps send a PM to the poster ( driftwood) and see if perhaps he still has one kicking around.

I realize it's near 4 years old but worth a shot perhaps.
Retired Pauly
Problem with being retired is that you never get a day off.
1987 D21-J SD25 KC
KJLGD21FN

handcannon
Posts: 57
Joined: 4 years ago

Re: Sd22 Runaway and diaphragm hunt

#18

Post by handcannon » 3 years ago

The link in plenzen's post has the same Zexel number linked to a SD-22 diaphragm, post #62, that is on the invoice that came with my spare diaphragm. I don't know where Oregon Fuel Injection sourced the diaphragm they got for me, but apparently the diaphragm is available somewhere.

Don

IDIDetroit
Posts: 13
Joined: 3 years ago
Location: Vernon, Florida

Re: Sd22 Runaway and diaphragm hunt

#19

Post by IDIDetroit » 3 years ago

I managed to find a diaphragm local and a oil splash shield. I got it all installed and hooked up, fired it up it skipped for a whole 5 minutes and turned the neighborhood white, thats never happened before. Once its warmed up it idles like a singer sewing machine but if you give it any throttle it belches black smoke then turns back to white and skips if you hold it at any throttle. Im thinking that while I was trying to get it shut down it hurt itself and is really wounded. Is there any possibility of finding internal parts anymore?

waynosworld
Posts: 517
Joined: 7 years ago
Location: Vancouver Washington USA

Re: Sd22 Runaway and diaphragm hunt

#20

Post by waynosworld » 3 years ago

Does it turn over evenly when you start it, or does it go slow then fast briefly then slow again?
Have you checked your valve lash/adjustment?
Has this engine been over heated?
I know the voices are not real,
but they have some really good ideas.

IDIDetroit
Posts: 13
Joined: 3 years ago
Location: Vernon, Florida

Re: Sd22 Runaway and diaphragm hunt

#21

Post by IDIDetroit » 3 years ago

It cranks over evenly and fires within 3 rounds I haven't checked the valve lash yet, I was really frustrated with it when I left it and since I've owned it it's never been overheated, I can't speak for before then. This is the first time it's ever done anything like this, it ran perfect before the rack got stuck open.

waynosworld
Posts: 517
Joined: 7 years ago
Location: Vancouver Washington USA

Re: Sd22 Runaway and diaphragm hunt

#22

Post by waynosworld » 3 years ago

White smoke is either steam from head gasket being blown, or un-burnt fuel which has this funny smell.
Skipping I am assuming is missing, missing can be caused by a lot of things, first thing is to find out which one is missing, start it up and crack open each injector line at the injector, which ever one/cylinder is the issue will not change the rhythm of the idle, you will then know which cylinder is the issue, you should see fuel leak out when you crack open each injector.
Then you need to check the valve lash on that cylinder, if both the pushrods are in position and the lash is not too tight then it would not be that.
I know the voices are not real,
but they have some really good ideas.

IDIDetroit
Posts: 13
Joined: 3 years ago
Location: Vernon, Florida

Re: Sd22 Runaway and diaphragm hunt

#23

Post by IDIDetroit » 3 years ago

Well, I can't say that todays been all that great, I checked the valve lash and all of them were at .014 hot, so thats out of the question. Halfway through the warmup period it started missing a little more and I started to hear a clatter coming from cylinder 1 and when I took the injector line off of number one it stopped halfway missing, just a dead miss, it even stopped smoking as bad besides the little puff of black. So I pulled number 1 injector to see what it popped at and didnt get that far, it was oil soaked from the sealing surface down and when you spun it it pushed oil out of the hole. Im thinking number 1 may have problems with a piston or a ring, but I've been wrong before. Any input would be welcomed

waynosworld
Posts: 517
Joined: 7 years ago
Location: Vancouver Washington USA

Re: Sd22 Runaway and diaphragm hunt

#24

Post by waynosworld » 3 years ago

I am not sure what you mean by it half way missed and then it totally missed when you loosened the injector.
When you crack each injector line, the cylinder that has the issue will not change the rhythm of the engine idle, if it changed the rhythm of the engine then it is not that cylinder.
What I am saying is when you crack open the injector line and nothing changes, that is the cylinder with the issue.
I know the voices are not real,
but they have some really good ideas.

IDIDetroit
Posts: 13
Joined: 3 years ago
Location: Vernon, Florida

Re: Sd22 Runaway and diaphragm hunt

#25

Post by IDIDetroit » 3 years ago

What I was saying here is that it would fire every other time like it was trying to fire on that cylinder, when I took number one injector loose it ran a little smoother and was steady on 3 cylinders instead of 3 and a half if that makes any sense. But what worries me is that when I screwed number 1 injector out it was covered in oil and oil slobbered out of the hole spinning it by hand.

waynosworld
Posts: 517
Joined: 7 years ago
Location: Vancouver Washington USA

Re: Sd22 Runaway and diaphragm hunt

#26

Post by waynosworld » 3 years ago

Oil can get by the valve cover and get in the hole that the injector is in, you will not be able to see it until you take the injector out.
Only the very end center of the injector actually sees the pre-combustion chamber, there is a copper washer in the bottom of the hole that makes the seal(at least on the SD22 head), that is why only the center of the injector end gets corroded over time, oil can get all the way in there if enough oil gets in that hole and sits there long enough.
As I said, when I have a miss I crack open each injector line where it connects to the end of the injector, when I find the one that doesn't make the engine miss worse, that is the cylinder with the issue.

There may have been more damage to the injection pump also, where did all that metal go?
I know the voices are not real,
but they have some really good ideas.

IDIDetroit
Posts: 13
Joined: 3 years ago
Location: Vernon, Florida

Re: Sd22 Runaway and diaphragm hunt

#27

Post by IDIDetroit » 3 years ago

Thats a very good possibility that the pump is messed up, I was kinda hoping it wasn't at this point. So the oil could be fine? would it hurt to put a compression gauge on that cylinder and what psi should I be looking for? I understand that you would crack the injector lines to see which one is missing, I used to do that on all of the old Gm diesels. I cracked all of the lines one at a time, 2 through 4 made it miss a lot worse like it was missing on 2 cylinders now. But when I cracked number 1 the intermediate miss went away and it became a dead miss, Im sorry if something isnt translating, Im kinda finding it hard to say what exactly it's doing but number 1 seemed to effect it the least when it was cracked, even smoking less.

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