Gungy oil in 'Nana, now engine knocking.

[jimllshiftit]

Hello everyone.

A few weeks ago I noticed my oil light would stay on longer than usual when I set off in the morning. Not for too long but longer than id like. No time to look into in for the rest of the week but when the weekend eventually came I decided to drop the oil and see what was going on.

I removed the sump plug but nothing came out at all. I removed the oil filter and a great big sticky plop, about the same consistency of porridge dropped out..... this didnt look good.

After running a can of "sea foam" through it I managed to get the old oil flowing out of the sump. I then ran flushing oil through the system with another can of "sea foam" in the hope that would really clean to gunge out of it. Then I replaced the oil with good stuff (5w 40 semi? cant remember) but the engine started to knock within a mile of home.

What shall I do? Ive now got two dead engines here and they arent making them anymore so theres a part of me that thinks I should try to repair them. The sensible way is to find another engine and drop that in, but then I have a feeling ill end up with a third dead engine before long.

What do you reckon is causing the knocking? Is it worth investigating it with a view to repairing it?

[dumper]

You have probably knocked out the big ends how long had the oil been in / had you put in the wrong spec before the problem/ or mixed different types of oil I’ve only used mineral oil 2.5 di s.

[MinorMatt]

Most cost effective method is probably to stick another engine in.

In slow time you could then look at the engine that has died and see whats damaged, if you are lucky it might just be big end shells required?

Why have the other engines died though?

[jimllshiftit]

The oil that was in it, that went gungy was A3 B3 5w 30 HC "Synthesis".. doesnt say Synthetic but neither does it say Fully/Semi/Mineral either.

Including the dead engine that is in the van there are two dead engines. Im running them on veg oil which caused the first engine to "polymerise" its oil. This engine doesn't seem to have done that as I haven't got the horrible silicon type lumps in the oil and up the dipstick, nor have I been anything like as hard on this engine in cold months. The oil was thick but it was consistently thick throughout, whereas the first engine had thin oil, thick oil, and rubber lumps.

In hindsight ive probably done way too many miles in it without realising. Gibraltar and back to the Midlands this time last year. Aberdeen last Christmas. Carlisle god knows how many times. Surely I changed the oil last summer? Was that the summer before? The wheels on this van never stop turning.... i dont think ive changed it for ages.

[dumper]

Yes it’s easy to let time run away and lose track of when something has been done I make sure nowadays that I keep a record of what I’ve done I don’t no anything about running veg oil and it may be better with mineral oil and more regular oil changes as for the di I don’t think it was ever recommended to run synthetic oils we never used it at work

[jimllshiftit]

Time does run away, and these vans aren't like cars. The only time they're sitting still, im not, and things get missed and put off and forgotten about, until its all too late.

This isnt a veg oil issue. Its an engine oil issue. Poor quality oil, possibly of the wrong type, and not being changed.

Oh well, engine number three beckons........ but I cant help asking myself, how long will these lumps still be in circulation?

[dumper]

As I said I don’t know but my thoughts on the veg oil contaminating the oil is it may be the same when you get diesel over fueling contaminating the oil .

[metalworker0]

Time does run away, and these vans aren't like cars. The only time they're sitting still, im not, and things get missed and put off and forgotten about, until its all too late.

This isnt a veg oil issue. Its an engine oil issue. Poor quality oil, possibly of the wrong type, and not being changed.

Oh well, engine number three beckons........ but I cant help asking myself, how long will these lumps still be in circulation?

You ever see a chip fryer that has congealed veg oil around it on the walls , almost no solvent breaks it down - only caustic substances break it down. you don't want that stuff in your engine.
No amount of flushing is going to get those lumps out ..only a complete strip down.
Years ago they used to run racing cars and bikes with castor oil in the sumps or oil tanks ...that's were Castrol (CASTOR OIL) got its name ..it was known for its protection ..but only for a couple of races then the engine would have to be stripped down cleaned and rebuilt - they still sell it today its called Castrol R, but most people just add a tea spoon to a petrol tank to make their exhaust smell authentic.
if diesel evaporates it leaves behind nothing .......veg oil leaves behind a thick gummy mess.
all the best..mark

[jimllshiftit]

Veg oil isn't clever but the cost, abundance and ease of transferring these engines far outweighs the cost of fuel between them blowing up.

It does appear these engines are becoming more expensive though and thinner on the ground.

[Keef]

Its worth doing some research on the web if you're going to use cooking oil there's plenty of info out there.

"Change of engine oil
Unburned fuel – especially during cold starts and at high engine speeds – gets into the engine oil and worsens its lubricating properties or polymer chains form in the engine oil, which can agglomerate into lumps and clog pipes and filters. This problem occurs especially when using modern fully synthetic lubricating oils, obviously fully synthetic oils bind foreign substances (free radicals) very well, what they should – if there are not too many.

Pure diesel fuel begins to evaporate at about 55 ° C. Thus, when the engine oil reaches this temperature while driving, the diesel fuel evaporates from the engine oil. Since vegetable oil, unlike diesel, does not start to evaporate until about 220 ° C and the engine oil never reaches this temperature, vegetable oil inevitably accumulates in the engine oil. A conversion of the vehicle to the operation with vegetable oil can only slow down this process, but not prevent it. Therefore, it is always advisable to check the oil level regularly and to halve the oil change frequency."

[Keef]

Its worth doing some research on the web if you're going to use cooking oil there's plenty of info out there.

"Change of engine oil
Unburned fuel – especially during cold starts and at high engine speeds – gets into the engine oil and worsens its lubricating properties or polymer chains form in the engine oil, which can agglomerate into lumps and clog pipes and filters. This problem occurs especially when using modern fully synthetic lubricating oils, obviously fully synthetic oils bind foreign substances (free radicals) very well, what they should – if there are not too many.

Pure diesel fuel begins to evaporate at about 55 ° C. Thus, when the engine oil reaches this temperature while driving, the diesel fuel evaporates from the engine oil. Since vegetable oil, unlike diesel, does not start to evaporate until about 220 ° C and the engine oil never reaches this temperature, vegetable oil inevitably accumulates in the engine oil. A conversion of the vehicle to the operation with vegetable oil can only slow down this process, but not prevent it. Therefore, it is always advisable to check the oil level regularly and to halve the oil change frequency."

The last word should be 'intervals' not 'frequency'

[jimllshiftit]

If i DOUBLED my oil change frequency I still wouldn't be nearly enough.

In the long rub I think ive done pretty well out of Veg Oil, but I do agree, more frequent maintenance is required if Im going to eek out more life from these engines that aren't going to be around for ever. Part of my problem is that I get up, get in the van, go to work, and go home and the van asks for absolutely nothing in return until something is seriously wrong. Theyre just so bloomin' dependable!