Glow plugs and injectors, when to throw old ones out

What is the normal considered time to pull these and do an inspection/replacement?

From my basic understanding glow plugs about 50,000 – 80,000 kms.

What is it for injectors?

Motor DZ30 Di

Brand new long motor, 500 kms. Just replaced the old one at 168k km as it had a head crack and cooked a few things.

New motor: NADS and glow plug timer set to 15 seconds. Also came with ceramic glow plugs, thanks to Nissan.

Also changed DMF to a single mass one, new heavy duty clutch and an all metal radiator, plus a few other minor mods.

There is no set timeframe for glowplug replacements, but I think replacing them at anywhere from 100,000 to 150,000 is a good thing on these motors as I have read about so many with the tips fallen off, and this can't be a good thing.

Injectors are made for a lifetime on the 3 Litres .... they either work or they don't and aren't usually serviced like the older style injectors - replace only when necessary. You can run a fuel system cleaner through them if you are using your old ones.

It would appear that with all the reports of glow plug tips coming off and breaking in head, you should use the most expensive brand name plugs you can afford. Or am I just being over cautious.

I gave a value of 50k – 80k km for glow plugs in the Di motor based on readings both here and elsewhere. This was for the ceramic tip ones.

Note in the Di motor the glow plug initially stays on for a longer time vs the common rail motor. Suggested times for start up on a standard, no mods, Di is 5 minutes or until the motor reaches operation temp.
Hence the concept of a glow plug timer for the Di motor.

Purchasing the most expensive brand name does not solve the matter of a warm motor spraying fuel on an over extended hot glow plug. They all suffer crazing and tip loss.

As for the concept of life time injectors.. Don’t believe a word out of Nissan on this.
True they are a replace non fixable item and at about $1000 plus not cheep to replace, but a fully functioning injector is better than a so called "operational" one.

Cleaners do the job, but don’t fix wear in the jet, nor its spray pattern as the injector gets old.

At present my opinion is:

1. Install a glow plug timer set at about 30 seconds operational time. This overrides the on board computer time set.
   Details re these are on this site and the other Patrol site.
2. 80,000Km glow plugs removed and physically checked. Any crazing all replaced. No 4 cyl being possibly the worst culprit for issues.
3. 100,000km injectors physically checked. Any variance from standard , replace all.

With respect to glow plugs, much is based also on what I saw when my ceramic Nissan plugs came out at about 150K and only one was operational. The rest lost tips o r were non operational. At 168k the metal ones I had showed huge burn wear. Most of this was due to the long time the tips were kept hot by the system.
The injectors were covered in carbon crud, fuel cleaner or not. How much the actual jet was effected I cant say but I suspect it was, based on fuel consumption a bit wider than specs.

Quote:

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Originally Posted by outback

I gave a value of 50k – 80k km for glow plugs in the Di motor based on readings both here and elsewhere. This was for the ceramic tip ones.

Note in the Di motor the glow plug initially stays on for a longer time vs the common rail motor. Suggested times for start up on a standard, no mods, Di is 5 minutes or until the motor reaches operation temp.
Hence the concept of a glow plug timer for the Di motor.

Purchasing the most expensive brand name does not solve the matter of a warm motor spraying fuel on an over extended hot glow plug. They all suffer crazing and tip loss.

As for the concept of life time injectors.. Don’t believe a word out of Nissan on this.
True they are a replace non fixable item and at about $1000 plus not cheep to replace, but a fully functioning injector is better than a so called "operational" one.

Cleaners do the job, but don’t fix wear in the jet, nor its spray pattern as the injector gets old.

At present my opinion is:

1. Install a glow plug timer set at about 30 seconds operational time. This overrides the on board computer time set.
   Details re these are on this site and the other Patrol site.
2. 80,000Km glow plugs removed and physically checked. Any crazing all replaced. No 4 cyl being possibly the worst culprit for issues.
3. 100,000km injectors physically checked. Any variance from standard , replace all.

With respect to glow plugs, much is based also on what I saw when my ceramic Nissan plugs came out at about 150K and only one was operational. The rest lost tips o r were non operational. At 168k the metal ones I had showed huge burn wear. Most of this was due to the long time the tips were kept hot by the system.
The injectors were covered in carbon crud, fuel cleaner or not. How much the actual jet was effected I cant say but I suspect it was, based on fuel consumption a bit wider than specs.

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We are on the same wavelength ... we both agree that these components need to included in some sort of service routine ( which isn't recognised by Nissan - as they don't test these components ).

I do think that the spray patterns will change over time with the injectors, and this could definitely lead to engine damage ( just as it can on any diesel ) - just haven't formulated in my thinking what the best average is to get things checked or replaced ..... I personally know of some of the earlier Di 'grenades' that have never been touched and were over 320,000 klms.

Mic

Quote:

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Originally Posted by 4bye4

It would appear that with all the reports of glow plug tips coming off and breaking in head, you should use the most expensive brand name plugs you can afford. Or am I just being over cautious.

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The standard Nissan ones are ceramic tip, which are supposed to be able to handle the higher temperatures better, and last far longer than the metal tip ones. These are superior, except when they break off the tips, as the ceramic is harder than steel, and there isn't much room between the valves and the piston top - not enough for it not to leave damage before it somehow goes out the exhaust valve

There are lots that are going to the metal tip ones, but I would be wary of doing this without modification to the glowplug timer circuits

Trying to work out which glow plugs I need for my 2008 ZD30 Common Rail. I haven't pulled the original ones out yet. However I know that the original Nissan ones (11065MA70A) are NKY (NGK) Y538J. From my searching it looks like these are metal tip, is this correct?

If so, I wouldn't need a timer then.