* Cold Weather Starting Difficulty *

[moose60]

Seeing this also brought to mind a couple anomalous starting issues it has had in the last six months. One time when it had been sitting for several days without being driven it stalled several times even though the temperatures were in the 70's. Another time, most untypically, it just wouldn't start until I operated the priming pump a few times. Could these be signs of lift pump failure?

This does sound suspicious to me. Especialy the part about not running untill the primer was used. There is a newer design available for the priming pump, which is supposed to eliminate all leaks. Mine cost about $18. This type of priming pump has been mentioned on this board before, it does not need to be screwed out to pump.
I know a man here in Seattle who has had some starting troubles with motors like these (inline Bosch inj. pumps) includina a Datsun , that he swears he has fixed by replacing the priming pump. It didn't work for me though.
Good Luck
Byron

[EvergreenSD]

Could you tell me where you were able to buy the priming pump kit? $18 sounds like a good deal. I need to review the blow-up drawings to see, would this kit also remedy lift pump problems that occur while the engine is running? In other words, does this kit replace all of the key parts in the pump or just those related to priming?

[asavage]

I could have sworn that I posted this before, but a Search did not reveal it.



There is a fellow who sells them on eBay for $15 (plus shipping, which is $7 for me).

Hello:

The Nissan diesel SD engines (mostly) use an inline Kiki-Diesel IP that is licensed from Bosch. It looks to be very similar to the old Mercedes IPs. The primer pump leakage problem is the same.

Do you know if this primer pump (at auction) is a replacement for the Zexel/Kiki-Diesel pump?

Here's a parts illustration of the one used on the Nissan SD engines:
https://asavage.dyndns.org/ftp/Nissan/SD22/primer_b.jpg
and a pic of the IP it fits:
http://asavage.dyndns.org/ftp/Nissan/SD ... 7W04-2.JPG
http://asavage.dyndns.org/ftp/Nissan/SD ... _dia-r.jpg
http://asavage.dyndns.org/ftp/Nissan/72 ... ps_02b.jpg

Regards,
Al S.

His reply:

Randy Steele The MB Partsguy" <randy@epsparts.com>
Date: Sat, September 16, 2006 1:35 pm
To: asavage@iname.com

Everything except the last picture looked close. The last one is hard to tell because of the angle.

I can say this, if you buy one and it is not the same you are more than welcome to return it. Return by 1st class would only be a few dollars.

Thanks,

Randy Steele
The MB Partsguy

800-334-2749 / 805-683-4020

http://www.autopartsguru.com

mailto:randy@epsparts.com

http://search.ebay.com/_W0QQfgtpZ1QQfrp ... mbpartsguy

I'm reasonably sure that the MB primer and the SD2x primer are the same. The pic on his latest auction is lousy, but you've seen it in the Lift Pump thread.

[EvergreenSD]

Thanks for the tip. I just bought one from mbpartsguy. I'll let you know how it works out. Meanwhile I will try out a couple more things when I get home to see if I can learn anything else.

[moose60]

Al is correct on MB/Datsun interchangeabiltiy on this item. I got mine at an MB parts house on Aurora here in Seattle. I just told the guy that I had a Kiki pump, liscenced by Bosch. He knew exactly what I needed. The old style is still available, and cheaper, so make sure the one you get is the new style.
Byron
*One minute later*
Oops. Looks like you got things mostly taken care of, Evergreen. I do not think that this primer will fix any other problems with the lift pump. It is fairly self contained.
B

[philip]

I'm working on a new theory involving the lift pump. I recently noticed that the priming pump leaks when I pump it. Could this be related to my problem? The pump does not leak the rest of the time but is it possible that it is drawing in air through a rip in the diaphram or something of the like?

Lift Pump thread

[philip]

I'm working on a new theory involving the lift pump. I recently noticed that the priming pump leaks when I pump it. Could this be related to my problem? The pump does not leak the rest of the time but is it possible that it is drawing in air through a rip in the diaphram or something of the like? Maybe this would explain why the truck had an electric fuel pump by the tank when I got it, though the wires had been cut.
Seeing this also brought to mind a couple anomalous starting issues it has had in the last six months. One time when it had been sitting for several days without being driven it stalled several times even though the temperatures were in the 70's. Another time, most untypically, it just wouldn't start until I operated the priming pump a few times. Could these be signs of lift pump failure?

You -do- know that the OEM primer pump has to be "stowed" when not in use ... right? If the OEM primer is left "unstowed" the pump prime will likely be lost around that leaking seal you've noted after sitting a few days.

Depress the primer plunger fully and then screw it clockwise until seated after using.

[EvergreenSD]

Well, I got my updated primer pump installed. It went in with no problems. Though the first startup with the new pump went perfectly, uh well . . . the problem is still not solved. I think I removed one more little problem that was probably contributing just a little bit to it not being right but I have yet to get to the real issue. The cold starts do seem just a little bit different in a way I can't define. Alot of this may just reflect my changing perceptions and the theories I am entertaining at a give time.

Now the rough running after the first start of the day seems more like surging. There is a rythm, kind of an osscilating pattern to the engine accompanied by lots of white smoke. I am now leaning towards a governor diaphram issue. I will continue my quest of that thread. I am thinking that the diaphram (or any gunk that might be on it) gets stiff when cold and also may exacerbate any leaks it may have. I have yet to turn in the mileage numbers that I should suspect from this truck so this could be explained by a faulty diaphram as well.

[asavage]

Now the rough running after the first start of the day seems more like surging. There is a rythm, kind of an osscilating pattern to the engine accompanied by lots of white smoke.

What you describe is exactly how one of mine ran with a hole in the tip of one GP.

I'll bet $10 on a GP system failure, and hedge that bet with a $5 bet on low compression on one cylinder. It is either lighting off on all four and dropping back to three (with the oscillation due to feedback via the throttle body signal to the pneumatic governor), or lighting off on three. The white smoke is cold, unburned raw fuel.

I wait for the GP to cycle off on a cold start, then turn the key off and back on to start.

Wait for the "clunk" of the relay, not the GP light to go out.

You said you replaced the GPs; are you certain they're the right ones?

[EvergreenSD]

I regret that my limited time available has not allowed me to progress more quickly. I would like to address your wagers because I value the wisdom available.

First, GP's. These have been recently replaced with NGK's using the part number I found on this board for the longer-duration type plugs. Recently, when I had removed the injectors because I was this close to having them rebuilt, I was able to observe the GP's working. It took about 10-15 seconds for them to reach a crackling cherry-red glow and they remained hot until the relay clunked off. My procedure for cold starts has been to perform this cycle, turn the key off and on so they come back on, then I start. Frankly, when I hear them clunk off again 20 or so seconds after startup it doesn't seem to make a whole lot of difference to the running problems.

Second is compression. This is frankly the one that makes me cringe. Simply put, I cannot afford to rebuild this engine so this answer would mean that my SD22 experience would end in embarrassing and damaging failure. I did consider this, however, before I invested in repairing some of the other systems and took what I considered to be resonable precautions.
I bought a diesel compression tester from Harbor Freight and tested the compression with what I thought to be encouraging results. I used an adaptor through the GP holes. I tested with the engine warm, the throttle blocked open and the DPC unplugged of course. I cranked 10-12 times per cylinder as this seemed to be where the readings stabilized. My results for the rear 3 cylinders were 425, 420, and 430 psi. I believed this to be good compression and I was most pleased with the consistency between the cylinders as I know the testers will vary in the raw numbers they provide. The front cylinder I was not able to test satisfactorily because of the limited clearance that has been proviously discussed. I was able to get an adapter in the hole after cutting off the schrader valve on the adapter. This meant that the tester was not able to accumulate pressure but I was able to observe the spike as the cylinder came up. This spike hit about 175 psi. This appeared to be the same reading that the other three cylinders registered after a single stroke.
In addition to this, the engine doesn't display other symptoms that I associate with low compression. There is not excessive blow-by out of the draft tube and it does not drip on the driveway though I understand it would not be particular cause for alarm if it did a little. Also, the blow-by I feel when opening the oil filler cap with the engine running compares favorably with what I felt on a gasoline engine of smaller displacement that also ran on open breather and yet was still able to drive daily ('69 Corona).

Sorry for the long-winded post. I wanted to share my process for the record to see what kind of a response I would get. I appreciate all the help and support I have received already. I really want this to be a viable vehicle but I also need third party advice to avoid being blinded by my own hope or foolish optimism. Keep clattering . . .

[asavage]

First, GP's. These have been recently replaced with NGK's using the part number I found on this board for the longer-duration type plugs. Recently, when I had removed the injectors because I was this close to having them rebuilt, I was able to observe the GP's working. It took about 10-15 seconds for them to reach a crackling cherry-red glow

I've not done that -- had the GPs mounted in the head when testing -- but that seems like a loooong time to get to red. Loose, they get red pretty fast.

I guess I have no more useful suggestions at this time.

[EvergreenSD]

Compression question:

Since I saw that Zoltan has just posted a compression reading as well, I thought now would be a good time to ask the experts. In your opinion what would be good or acceptable compression readings to rule that out as a cause of driveability issues? To be honest, I was a little confused by Al's readings exceeding the specs, was the engine really in that good of shape?
I would have to double check but I believe I remember my book specifying around 425 psi with rebuild recommended around 350-360. I was relieved to find the 3 good readings I was able to take all above 400 and I was especially pleased to see them so consistent, within 10 psi. Was my relief unfounded? I haven't been using oil or dripping out the draft tube either. Thank you for sharing your knowledge.

[asavage]

I was a little confused by Al's readings exceeding the specs, was the engine really in that good of shape? I would have to double check but I believe I remember my book specifying around 425 psi with rebuild recommended around 350-360.

You're confused? How do you think I feel?

The FSM says "Standard" reading is 427. Three of mine measured above that. I suppose I should either calibrate my gauge or pick up a second one. In theory, my readings should read low, due to the tester's hose volume affecting the effective CR.

In my experience with several diesels over the years, readings less than 350 = hard starting (for automotive IDI diesels).

You haven't tested the No. 1 cylinder yet, right?

What is the measured voltage at No. 1 GP during glow? Use clip leads, don't try to hold the probe on the terminal.

[zen]

EXCUSE me! This post is going around and around...check the glow plugs,do this..blah blah..

All these things were pointed out on the first page..

ADVANCE THE TIMING A TINY BIT!!!!!!!!! for Pete's sake.

See what happens..takes 5mins,costs nothing..sorts the problem ususally (if it does not then put it back,10 mins wasted,big deal..)..pointed all this out on page 1..(along with checking the glow plugs,compression etc..)

As I have already said, and got ignored and "corrected" by the same people who pointed the same thing as me out on the next page, you are describing EXACT SAME FAULT AS MY NOW NON (read NON) smoking and hunting at start up sd33t.

ADVANCE THE TIMING!! This cure was given to me by very established diesel pump shop local to me after many hours headbanging and £'s spent on rebuilding injectors etc. TRY IT..

(if you have tried it and it did not work, then i will crawl away with head hung low with shame but i bet you havn't have you????)

[EvergreenSD]

I did try it. Yesterday after your post I mean, so don't feel the need to crawl anywhere. I am waiting to get a little real-world experience before I comment on the results, though the initial result seems very promissing. Thanks for speaking up, I can be a little thick at times. I can tell you for sure that (accidentally) retarding the timing a hair certainly made it run worse. I said I can be a little thick. I will keep you posted on what I find.