I recently replaced my injectors with rebuilt injectors from greazzer on my '84 300TD. As a maintenance procedure is there any common wisdom about how often a diesel purge should be performed?

Many will say never as they believe that its snake oil, others will say yearly because they believe that it makes there car run better. I think its really up to you how often you want to run it.

__________________
2004 F150 4.6L -My Daily
2007 Volvo XC70 -Wife's Daily
1998 Ford F150 -Rear ended
1989 J-spec 420SEL -passed onto its new keeper
1982 BMW 733i -fixed and traded for the 420SEL
2003 Volvo V70 5 Speed -scrapped
1997 E290 Turbo Diesel Wagon -traded for above
1992 BMW 525i -traded in
1990 Silver 300TE -hated the M103
1985 Grey 380SE Diesel Conversion, 2.47 rear end, ABS -Sold, really should have kept this one
1979 Silver 300D "The Silver Slug" -Sold

This is one case where the Rhythm Method hardly ever works. I usually do it as part of the fuel filter change process. Can't hurt.

Of course if you are unlucky enough to get some bad fuel you'll want to do it then as part of the recovery.

I do it every 15k with a fuel filter service.

__________________
Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k

In my book, this is an "as needed" corrective procedure, not a normal maintenance procedure. If you're using #2 ULSD and your fuel system from tank to injectors are good, and your glow plugs are good, you may never need to do this.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I agree with Max.

Bought my car a year ago. First diesel. The car had barely been driven for 2 years before I took possession. Within a few hundred miles it was barely able to get out of its own way. I changed the filters and that helped, but it was still a pig.

I ran Lubri Moly through it and the car got a new lease on life. The clear hose I attached quickly went BLACK as the crud 'cooked' (?) off the injectors. The idle smoothed out and the engine got quieter. Its also significantly more powerful. Needless to say, I was very pleased. That was about 8000 miles ago. No issues since then besides a dirty first stage filter that caused the idle to lope a bit.

You have rebuilt injectors.....you won't need a diesel purge for a LONG time.

If you really want to have it as a maintenance schedule then just do it while you are having your fuel filters serviced like Jake mentioned.

Doing the purge isn't that bad, it's actually kind of fun imo. And you can listen to the car on the purge and on base fuel to see if it sounds any different. If the engine sounds the same on both the additive and fuel (mind does), then you know your engine is generally fine.

In the past however, my engine used to shake terribly and was really loud till I put it on purge. However, that isn't the case anymore after I changed out the valve tappets, got new delivery valves, and got my injectors rebuilt by the great greazzer

__________________
1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.

This is a good point - it can be used as a trouble-shooting tool to determine if a rough running issue is fuel related or something deeper like a blown head gasket or broken rings.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I like to use it as a pre-fill for the fuel filter. Cetane is through the roof so the engine lights much easier on the first restart.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

FWIW, diesel purge did jack diddly squat for my SDL's engine. Some nastiness came out, sure, but it didn't do anything to fix its running problems. Mine was all mechanical wear to the delivery valve faces. Resolving that problem resolved the running issues. Diesel Purge did mask the problem (silent and smooth) when running on it, but back on diesel and it was right back to shake, rattle, and roll.

Your mileage may vary. I'm not a huge fan or proponent of any "cure in a bottle".

__________________
Current stable:
1995 E320 149K (Nancy)
1983 500SL 120K (SLoL)

Black Sheep:
1985 524TD 167K (TotalDumpster™)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)