NissanDiesel Forums

Ouch!
Odd Ball?
A 1987 D21 Nissan KC with an SD25 diesel engine, dual batteries, LSV for the rear brakes, 14 inch wheels, dual piston calipers, and multi sealed fuel injector’s (two gaskets I might add, not just one) yada, yada, yada, is NOT AN ODD BALL!!.
It's at best,,,,, perhaps an anomaly!!

Political correctness you know!! Not quite as harsh!!

Paul

plenzen wrote:SNIP- ... and multi sealed fuel injector’s (two gaskets I might add, not just one) ... -SNIP- Paul

These injectors are not to have TWO gaskets. If you do ... there is danger of not sealing TIGHT the nozzel face to the cylinder head. In spite of what you find as replacement part, ONLY the nozzel gasket should be installed.

Doubled gasket horror

You will find that entire thread interesting.

Even if the FSM says to use both? I had them rebuilt and installed them with the two gaskets like it said and pulled them to the required torque of 51Lbs. I was not aware that there were issues in this matter? Should I remove them again and get new tip washers and reinstall without the copper ones?

Paul

plenzen wrote:Even if the FSM says to use both? I had them rebuilt and installed them with the two gaskets like it said and pulled them to the required torque of 51Lbs. I was not aware that there were issues in this matter? Should I remove them again and get new tip washers and reinstall without the copper ones?

Paul

The FSMs does NOT show two gaskets (nozzle and nozzle nut secured to cylinder head) ... nor did I find in my ORIGINAL "nozzle nut" on my 1982 SD22.


Please revisit *Injector Nozzle* thread

Do notice that the 'Zexel' replacement parts are used for many applications. In this case, the middle gasket (of three) is not used in this SDxx application.

I scanned the picture from the FSM and will post it with this. Pretty sure that is shows 2 gaskets, although I could be wrong

Paul

My SD25 (an 83 US model engine) had both gaskets as delivered from Nissan (mine had never been removed). Upon re-nozzling, the supplied replacements (upper washers) were too thick to properly crush the SS "dimple washers" at the tip. Somewhere there must be dimensions available to account for the tolerance stacking that happens when nozzles are replaced. It would be better to have both sealing washers in place with the proper crush. The alternative is to use just the nozzle seal (copper or SS "dimple washer") and torque to spec. It does work.
Terry

"exsimguy1" ... thank you VERY much for that personal information.

My '82 had the nozzle solid copper washers ... no nozzle nut gasket included at all.

Phillip,
I think the upper (larger) sealing washers would tend to keep contaminants (such as water) from leaching down past the threads and settling on or around the nozzle. This "stuff" tends to fall into the hole upon removal. With the upper washers in place, my usual high pressure air application to dislodge anything around the injector usually limits any intrusion of "stuff" into the combustion chamber (pre-chamber actually).

Terry

exsimguy1 wrote:Phillip,
I think the upper (larger) sealing washers would tend to keep contaminants (such as water).... -SNIP-
Terry

Well then ... a hard rubber or nylon washer would be sufficient and could not affect the smaller nozzle gasket thickness.

"Upon re-nozzling, the supplied replacements (upper washers) were too thick to properly crush the SS "dimple washers" at the tip. Somewhere there must be dimensions available to account for the tolerance stacking that happens when nozzles are replaced. It would be better to have both sealing washers in place with the proper crush. Terry

I have a set of Nissan copper "Nut Gaskets" here and they are .061 - .062 thick each. They are used however, but were the ones in there when I re-tipped a couple of years ago

Paul