Practically Classics Forum

Hi, wondering if you should change oil hot or cold.Cold being that all sediments will have drained to the bottom, hot being that everything is still suspended around everywhere.Any thoughts on subject welcomed.
jagit.

I always change mine hot if I can. When I have been out for a run (or driven it around the block). Leave it to sit for 5 minutes so all the oil drains back in to the sump then let it run out. It is much more pleasant than cold oil and it drains more quickly.

hot... nothing worse than cold oil running up your sleeve as you undo the sump drain

Hot - always.

Thanks all for that, will do hot oil change
jagit.

As others say, hot is the way to do it. I know what you mean when you say the sediment is at the bottom when the oil is cold; however, a lot of teh sediment turns fairly solid when cool and doesn't come out! When I did the first oil change on the big tractor, I drained the oil and then took the sump off (it's just a rectangular sheet steel plate) and there was over an inch of crud on it (and up the sides of the chassis, which works as part of the sump, with the block bolted on top of it). Being used to a nice light, clean sump, I nearly dropped the thing (and my head was right below it!

Taking the sump off is a routine maintenance job on these machines (David Brown), you are supposed to do it every three or four oil changes, as you have to clean the filter on the oil pick-up pipe! Obviously the previous owner didn't do that - and the engine is a replacement one, so you think he might have learnt his lesson when the first engine failed!

Change it hot and change it often. Any sediment should be trapped by the oil filter and not at the bottom of the oil pan. New oils are quite high in detergent, but if you have sludge, then switch to a diesel rated motor oil as it's usually high in zinc and high in detergent.

tractorman wrote:As others say, hot is the way to do it. I know what you mean when you say the sediment is at the bottom when the oil is cold; however, a lot of teh sediment turns fairly solid when cool and doesn't come out! When I did the first oil change on the big tractor, I drained the oil and then took the sump off (it's just a rectangular sheet steel plate) and there was over an inch of crud on it (and up the sides of the chassis, which works as part of the sump, with the block bolted on top of it). Being used to a nice light, clean sump, I nearly dropped the thing (and my head was right below it!

Taking the sump off is a routine maintenance job on these machines (David Brown), you are supposed to do it every three or four oil changes, as you have to clean the filter on the oil pick-up pipe! Obviously the previous owner didn't do that - and the engine is a replacement one, so you think he might have learnt his lesson when the first engine failed!

Ah the good old sump in the kisser. Smarts a bit (6 cylinder LR one in my case)

Yep, get it hot, and all the grot dispersed so that all comes out with the oil rather than leaving a layer of crap behind

I have never had the sump itself hit me in the face but I have had a sump full of oil all over me more than once.

I have never had the sump itself hit me in the face but I have had a sump full of oil all over me more than once.

Neither of the above have happened to me - However - I been down a pit / under the car and been removing the sump plug and had just got to final few threads when a workmate threw what looked like a rat into the pit out of a bucket shouting at the time 'watch the rat it bites' !! (it was just a bundle of rag) I turned round so quickly that I hit my forehead on the warmish downpipe of the exhaust - and while part dazed the sump plug was out - result = both my boots had filled with enough warm old engine oil that it was oozing out of the lace holes Obviously much laughter ensued from the above bar stewards on the workshop floor !!