Diesel engine flush

[Charlie's Bus]

1st post I have ever made here. I have a 1990 International School bus with a 7.3..... Jasper engine has 68,000 miles on it. Installed in 2007. The bus did not move for the last 2 years. I drove it 750 miles and change the oil. Here is my problem A very thick sludge came out. Do I flush the engine or repeat oil changes every 100 miles for the next 300/400 miles. Of I flush what do I use. The bus is being turned into a homemade RV. Help please....

[T1pper]

Hi,
Welcome.

I do not not really like engine flush products I am nervous they will "wash" the engine internals and reduce the lubricating qualities of the oil.

I would go for some frequent engine oil changes.

Lastly is it possible to drop the sump in situ and clean out the goo, this might be an option and may not cost that much (just for the sump gasket compared to several oil/filter changes) and possibly be quicker also???

Plus it will give you a chance to clean the oil pick up stainer.

[Gingerbread Man]

I think dropping the oil while the engine is warm helps it drain. Not piping hot, but warm oil will be thinner. Then maybe chuck a bit more in the top to help flush some through.

A full sump drop as mentioned is a good option as in my car, once the oil has drained through the drain plug, there is still a bit left in there.

Edited by Gingerbread Man on Wednesday 21st January 22:28

[Pumaracing]

Diesel engine oil is very high detergent anyway and does a decent job of cleaning the internals when it's new. I fail to see much benefit in doing anything other than changing the oil for decent quality new stuff at the recommended intervals.

[Doctor Volt]

T1pper said:

Hi,
Welcome.

I do not not really like engine flush products I am nervous they will "wash" the engine internals and reduce the lubricating qualities of the oil.

I would go for some frequent engine oil changes.

Lastly is it possible to drop the sump in situ and clean out the goo, this might be an option and may not cost that much (just for the sump gasket compared to several oil/filter changes) and possibly be quicker also???

Plus it will give you a chance to clean the oil pick up stainer.

I agree with T1pper, this is very good advice

[Doctor Volt]

Pumaracing said:

Diesel engine oil is very high detergent anyway and does a decent job of cleaning the internals when it's new. I fail to see much benefit in doing anything other than changing the oil for decent quality new stuff at the recommended intervals.

Pumaracing
If you fail to see much benefit from doing anything other than recommended oil changes it is time for you to stop posting to the technical forum

This is the posters 1st post and you have been of no help whatsoever

[powerstroke]

Charlie's Bus said:

1st post I have ever made here. I have a 1990 International School bus with a 7.3..... Jasper engine has 68,000 miles on it. Installed in 2007. The bus did not move for the last 2 years. I drove it 750 miles and change the oil. Here is my problem A very thick sludge came out. Do I flush the engine or repeat oil changes every 100 miles for the next 300/400 miles. Of I flush what do I use. The bus is being turned into a homemade RV. Help please....

Yes as others if you can get the sump off however what genraly builds up is a mix of soot and oil I would guess if its like most busses they spend a lot of time idling and then short journeys , my guess is a couple of oil and filter changes with cheap diesel engine oil will clear it out, then use a decent spec 15/40 like shell rimular ...

[hman]

Sump off and clean it properly is the best way - oil pickups can become blocked with dislodged sludge and then its oil starvation and boom.

[Sardonicus]

Doctor Volt said:

Pumaracing said:

Diesel engine oil is very high detergent anyway and does a decent job of cleaning the internals when it's new. I fail to see much benefit in doing anything other than changing the oil for decent quality new stuff at the recommended intervals.

Pumaracing
If you fail to see much benefit from doing anything other than recommended oil changes it is time for you to stop posting to the technical forum

This is the posters 1st post and you have been of no help whatsoever

I beg to differ everything the OP'er needs to know is in that post he was hardly being offensive was he? I actually thought that was good advice

[Mr MXT]

Doctor Volt said:

Pumaracing
If you fail to see much benefit from doing anything other than recommended oil changes it is time for you to stop posting to the technical forum

This is the posters 1st post and you have been of no help whatsoever

Are you not banned yet?

[Mr2Mike]

Gingerbread Man said:

I think dropping the sump while the engine is warm helps it drain.

You would drain the sump before dropping it!

[griff 200]

I get a lot of this in the agricultural world and always do a double oil and filter change on an engine that has had poor oil changes in it's life. If you think it's very bad remove the rocker covers as the top of the engine can get real bad you can re set tap pets at the same time , as said before standard engine oil and filter changes at close service intervals will soon clean it up. But don't be tempted to fill with some more modern high mileage oils as I have found these seam to remove all the carbon from around the piston rings causing massive oil consumption also bore glazing. Richard

[GavinPearson]

Personally I would use an aggressive flush like Wynn's and get the sludge out. You might need to use several flushes, and based on my (extensive) experience with the Navistar diesels, they need 30 miles of motorway driving from cold to get the engine oil to 90C.

Once the engine is flushed, you need to make sure you use the Ford / Blue Diamond / Navistar filter, pattern filters do not filter the oil correctly, and given that the engine is a HEUI (i.e. the oil drives the injectors) well filtered oil is very important in making the engine run well.

I recommend a 5W40 oil - it helps with the injector operation in the cold.

Consider using this product too:
http://www.enginestiction.com/?gclid=CIPz1Z6xpsMCF...

[hman]

GavinPearson said:

Consider using this product too:
http://www.enginestiction.com/?gclid=CIPz1Z6xpsMCF...

I really think oil additives are complete tosh - and this guys website doesnt increase my confidence in oil additives either

This sentence is in their Third paragraph

"Because stiction issues typically subside as the engine oil begins to warm (due to the oil thinning out),"



NOTE: First rule of comparisons- only change one thing at a time -


This sentence is in their Forth paragraph:

"The oil was drained and switched to a lower-viscosity oil (5W-40 synthetic Shell Rotella vs. 15W-40 conventional)"


1 Change!


"After the truck's dipstick read half a quart shy of being full, we topped off our 16-ounce jug of Archoil"

2 Changes!


Why not just add the archoil to the original oil and see if that cured it?- I guess probably because it wont cure it.

Would just changing the oil to 5w 40 have fixed it - we will never know.

[Pumaracing]

It does rather beggar belief. If stiction issues subside as the oil warms and thins out then putting thinner 5W/40 oil in the engine to start with before "testing" one's snake oil would seem to be a fairly major change.

It's also rather noteworthy that the recommended oil viscosity for very cold temperatures for the Ford F350 engine changes from 15/40 to something thinner like 5/40 or 0/40 at below 20F as this truck was tested in.

http://www.google.co.uk/url?sa=t&rct=j&q=&...

No st Sherlock. 15W/40 was too thick to work properly at 15 degrees F just like the manufacturers spec sheet indicated but 5W/40 was ok and our snake oil was the real reason for the improvement. Feck off.

If there really was any snake oil that did any good the oil manufacturers would have found it and used it in the oils we buy off the shelf. Things like ZDDP which actually do help tappet wear and actually is in the oil you buy.