Author Topic: Flushing OIl  (Read 1134 times)


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Flushing OIl
« on: August 10, 2021, 12:34:24 PM »
When I first started messing about with car engines, it was pretty common to run a flushing oil through the system at oil change time, I can't remember the last time I used a flushing oil as it seems to be not required any more, I do remember using an engine flush additive in the late 90s but that's probably the last time I used it, normally with my car engine I just drain the oil and top up with new nowadays and I had one car that specifically said don't use flushing oils or additives.

The LD1 though is a 50 year old engine, it comes from a time when flushing oils were in common use.  I can't find any info on using a flushing oil when servicing the LD1 in the manual I have downloaded or online, has anybody used a flushing oil/additive prior to an oil change etc. or is it just something that has never been done on these engines ?

The engine is of unknown heritage - I don't know when it was last serviced, how many hours it has been running for, if it has had an oil change or if it has just 'continuous' oil change via regular topups  :D.  I'm going to do a full check of everything and fill with clean oil, do the tappets etc. but want it as clean as possible before I add new oil.



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Re: Flushing OIl
« Reply #1 on: August 10, 2021, 04:04:32 PM »
There are flushing products available that you add to the old oil and run the engine a few minutes and drain. Any automotive parts store will have it.  If there is doubt about prior maintenance being done I would take the time to pull the 4 bolts out of the crankcase door and take a peek inside. I have had a few neglected LDs and SLs in the shop and the gunk in the crankcase was DEEP! A gallon of kerosene and a few minutes brushing got the worst out followed by a couple quick oil changes.
Collector and horder of about anything diesel


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Re: Flushing OIl
« Reply #2 on: August 10, 2021, 08:09:30 PM »
I used to just buy an engine's worth of cheap oil, drain the old (when hot), fill with the cheap stuff and run till hot, then change filters, drain and fill with good oil.

Now I just drain the old and fill with good oil.