Super sludge in a 4.0 jeep engine, need advice.

[hemitom]

Originally Posted By: FLORIDA
Given the info provided here, what oil do you think would be best for my engine in the long haul? I'm not talking about whatever cheap stuff gets used for the short interval changes, but after that knowing the kind of neglect this truck has had before.
Your use of T5 10w30 and the FLA-1 is as good as any for the 4.0.

 

[FLORIDA]

Originally Posted By: hemitom
Originally Posted By: FLORIDA
Given the info provided here, what oil do you think would be best for my engine in the long haul? I'm not talking about whatever cheap stuff gets used for the short interval changes, but after that knowing the kind of neglect this truck has had before.
Your use of T5 10w30 and the FLA-1 is as good as any for the 4.0.


Thanks, that oil is cheap enough to do for the short intervals and the long hauls.

 

[Kruse]

I've got two '96 Cherokees with the 4.0 engine. Not that I'm the Jeep expert, but if it runs good now, button it back up and run it as is. Use a good filter and it should have a long life left in it.

 

[Sunnyinhollister]

Well, if it was me, and I already had the intake and exhaust off, and I'm going to change the thermostat, I would simply pull the head. While it was off, I would hot tank it, clean the valves, maybe do a valve job or lap them, and replace the valve seals. You've already have done most of the work by removing the intake and exhaust so pulling the head is not all that much more difficult.

After that I would also drop the pan.

 

[Alex38]

I'd run a HM oil for the rest of that engine's life. MaxLife 10w30 would probably be my choice. Mobil Super HM would also be worth consideration, as its less expensive and you should be changing that oil (or at least the filter) every 2-3k miles for the foreseeable future.

 

[demarpaint]

That engine should be cleaned manually there's a lot of sludge in there. If you opt out, run short OCI's with 3,000-4,000 miles with a good dino HM oil and start adding a pint of MMO for the last 1,000 miles of the OCI. Then after doing this a few times run a qt. of MMO in place of a qt. of oil for the winter OCI and run that 3,000 miles. It took years for that engine to develop that mess it might take years to clean it up if you don't manually do it.

Opinions, products, and cleaning techniques vary. If it were my engine I'd at least clean under the valve cover, [and the oil pan only if it's easy to remove] then do what I mentioned above.

 

[Trav]

I have a couple of ideas that may help.
Use a cheap engraving tool to mark the rocker arms and remove them. Just start at the front and mark them on the side 1-12 and the holder 1-6 at the front to not the direction.

You will need 3 x 1 gallon cans of Berryman 996 Chem Dip Carburator and Parts Cleaner (Autozone) and a stiff parts cleaning brush. Do not use a wire brush any seal the brush hits will likely be ruined.

Drain the oil and replace the drain plug fill 5 qts of the parts cleaner in the pan.
Put the rocker arms and bolts in the 3 qts left in the can and leave them sitting in the cleaner till they are needed.

Chip away as much of the sludge as you can then wet the whole are down with the cleaner and brush (use the third can), you don't need to scrub it hard once the stuff begins to melt the sludge it will liquefy. The stuff does not seem to harm the valve seals but try to stay away from them as much as possible.

It wont take long for the stuff to work and the top end will be nice and clean. pour fresh cheap oil over the valve springs and reinstall the rockers pour some oil over them also before putting the holders back on, squirt some oil from a oil can through the valve springs to lube the stems.

Let it sit overnight and drain the pan, you will get most of the junk out. refill with the cheapest dino you can find and start the engine. Run it 5 min and change the oil and filter.
Personally when i do something like this and i have done a lot of them over the years i would run a pint of Kreen in the oil for 1K to clean up the oil passages, you could also use a qt of MMO if you don't want to order the Kreen.

Use something like PYB or Rotella 10w30 for the first few OCI then move to PP, PU or Mobil 1.
Change the PCV valve!
Diesel and a brush is not a very cleaner for this sort of thing. Do not turn or start the engine with the cleaner in the pan, you don't want to draw that stuff into the pump and onto the bearings, it will be a very dry start if you do.

I have used this method more than a few times with great long term success on cars the pan was not removable on with the engine in the vehicle.

 

[jfking106]

Originally Posted By: Trav
I have a couple of ideas that may help.
Use a cheap engraving tool to mark the rocker arms and remove them. Just start at the front and mark them on the side 1-12 and the holder 1-6 at the front to not the direction.

You will need 3 x 1 gallon cans of Berryman 996 Chem Dip Carburator and Parts Cleaner (Autozone) and a stiff parts cleaning brush. Do not use a wire brush any seal the brush hits will likely be ruined.

Drain the oil and replace the drain plug fill 5 qts of the parts cleaner in the pan.
Put the rocker arms and bolts in the 3 qts left in the can and leave them sitting in the cleaner till they are needed.

Chip away as much of the sludge as you can then wet the whole are down with the cleaner and brush (use the third can), you don't need to scrub it hard once the stuff begins to melt the sludge it will liquefy. The stuff does not seem to harm the valve seals but try to stay away from them as much as possible.

It wont take long for the stuff to work and the top end will be nice and clean. pour fresh cheap oil over the valve springs and reinstall the rockers pour some oil over them also before putting the holders back on, squirt some oil from a oil can through the valve springs to lube the stems.

Let it sit overnight and drain the pan, you will get most of the junk out. refill with the cheapest dino you can find and start the engine. Run it 5 min and change the oil and filter.
Personally when i do something like this and i have done a lot of them over the years i would run a pint of Kreen in the oil for 1K to clean up the oil passages, you could also use a qt of MMO if you don't want to order the Kreen.

Use something like PYB or Rotella 10w30 for the first few OCI then move to PP, PU or Mobil 1.
Change the PCV valve!
Diesel and a brush is not a very cleaner for this sort of thing. Do not turn or start the engine with the cleaner in the pan, you don't want to draw that stuff into the pump and onto the bearings, it will be a very dry start if you do.

I have used this method more than a few times with great long term success on cars the pan was not removable on with the engine in the vehicle.





Or he could just pull the head, drop the pan, and soak them both in LA's Awesome Cleaner, scrub the crevices with a tooth brush, then rinse them off. It's dirt cheap at Dollar General.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2949569#Post2949569

 

[Trav]

From the sounds of it he didn't want to tear the engine apart. Why make a project out of something relatively easy?

 

[hatt]

I would put it back together and run it until it quits years down the road. Changing the oil more often.

I wouldn't be surprised if the OP reports back in a few weeks about how the engine blew after "cleaning" it.

 

[Trav]

Why should it blow?

 

[eagle23]

Originally Posted By: Trav
I have a couple of ideas that may help.
Use a cheap engraving tool to mark the rocker arms and remove them. Just start at the front and mark them on the side 1-12 and the holder 1-6 at the front to not the direction.

You will need 3 x 1 gallon cans of Berryman 996 Chem Dip Carburator and Parts Cleaner (Autozone) and a stiff parts cleaning brush. Do not use a wire brush any seal the brush hits will likely be ruined.

Drain the oil and replace the drain plug fill 5 qts of the parts cleaner in the pan.
Put the rocker arms and bolts in the 3 qts left in the can and leave them sitting in the cleaner till they are needed.

Chip away as much of the sludge as you can then wet the whole are down with the cleaner and brush (use the third can), you don't need to scrub it hard once the stuff begins to melt the sludge it will liquefy. The stuff does not seem to harm the valve seals but try to stay away from them as much as possible.

It wont take long for the stuff to work and the top end will be nice and clean. pour fresh cheap oil over the valve springs and reinstall the rockers pour some oil over them also before putting the holders back on, squirt some oil from a oil can through the valve springs to lube the stems.

Let it sit overnight and drain the pan, you will get most of the junk out. refill with the cheapest dino you can find and start the engine. Run it 5 min and change the oil and filter.
Personally when i do something like this and i have done a lot of them over the years i would run a pint of Kreen in the oil for 1K to clean up the oil passages, you could also use a qt of MMO if you don't want to order the Kreen.

Use something like PYB or Rotella 10w30 for the first few OCI then move to PP, PU or Mobil 1.
Change the PCV valve!
Diesel and a brush is not a very cleaner for this sort of thing. Do not turn or start the engine with the cleaner in the pan, you don't want to draw that stuff into the pump and onto the bearings, it will be a very dry start if you do.

I have used this method more than a few times with great long term success on cars the pan was not removable on with the engine in the vehicle.


Trav's advice is top drawer, based on his doing this a number of times as a professional mechanic. And you don't need to do mechanical things that aren't easy to do in a driveway.

Even if I had access to pulling the head/pan, etc., I'd try his approach first.

The parts cleaner in the crankcase overnight will pretty well clear the oil pump screen of crud. The other steps have been used elsewhere by other professional mechanics with good outcomes.

And this engine may well run reliably for years.

 

[hatt]

Originally Posted By: Trav
Why should it blow?

It will probably be OK. I just wouldn't want the potential of a bunch of loose crud floating around in an engine that was running fine and in all likelihood would continue to do so for many years.

 

[FLORIDA]

Lots of good info here guys thanks. I'm not going to pull the pan, its just to hard of a job on this vehicle for my skill set and driveway. I am torn between just going with short interval oil changes or first using some kind of cleaner in the engine to get more sludge out. It seems like a split here, some would do it one way and some would do it another.

 

[cptbarkey]

uh, i'd pull the head and get it cleaned/reworked at a machine shop, drop the pan, and then hope for the best. that looks terrible.

 

[bigt61]

A lot of these guys just like getting their hands dirty and working on cars. I don't, especially after doing it for many years with race cars. Just run MaxLife 10W-30 or 40 for 4000 mile OCI for a few years. Change the filter every time. It will clean up on it's own. The Maxlife should slow down the oil pan gasket. If the freeze plugs were just weeping, I would've just chucked a few Bars Leaks pellets (NAPA) in there with some fresh AF and let it eat. Easy - only patience required. It's not like your trying to restore a Ferrari.

 

[Trav]

Originally Posted By: FLORIDA
Lots of good info here guys thanks. I'm not going to pull the pan, its just to hard of a job on this vehicle for my skill set and driveway. I am torn between just going with short interval oil changes or first using some kind of cleaner in the engine to get more sludge out. It seems like a split here, some would do it one way and some would do it another.

The bottom line is you need to make 100% sure the pickup screen remains clear. Cleaning the head as i described is easy and can be done with a minimum amount of tools.
Using the cleaner in the pan will liquefy anything in there and also the screen with zero effort on your part.
Its your engine and you do as you see fit but keep in mind if the screen plugs its pretty much a done deal, used engine or rebuild time.

IMHO this engine is probably beyond short OCI and in the sump as you drive cleaners.

 

[SteveSRT8]

After being neglected this long I would strongly agree that Trav has given you the easy and effective cleaning method. That should give you a 'leg up' on the crud and then you can run some Kreen through that baby and drive it for a LOOOOONG time.

Putting a good HM oil in it and hoping might work.

 

[BillyTheKid]

I don't know much, but this is what I would try since you are not interested in dropping the pan. I would buy the cheapest conventional oil like Supertech or something. I would run that for an extremely short time, probably no more than 1000 miles, with a fairly cheap filter, then dump it. Me being me, I would then take that old oil and probably filter it with a screen when putting it into another container out of your drain pan to see what it is like dirt/sludge wise. If it was not too bad, I would use it as chainsaw oil or something for garden tools. Then I would give Rotella 15-40 (1 gallon jug) with two quart of MMO a shot. I would run that again for about 1000-2000 miles then dump. At that point, I would just put in whatever you are going to end up using in the long run in and do 3000-4000 OCI from there on out. Personally, I would use Maxlife or the Rotella 10-30 or even a mix of Rotella 15-40 with 2 quarts of lower weight oil to balance the total weight of the oil out.

This is just what I would try to do. Some may say too brave or crazy, but I still have not hurt an engine with oil related issues with my crazy thinking yet.

 

[default]

Id be tempted to dump a quart or two of diesel in the crankcase along with a fresh change of cheap oil (overfill it to encourage some sloshing around) and let it idle or maybe even 2000 rpm for an hour, listening for the hydraulic lifters to collapse(no oil pressure, clogged pickup), then change the oil and see how fast it turns black. The bottom end of a 4.0 is very strong and tolerant to abuse, they been known to run for a long time with very little oil pressure. Accidentally clogging the pickup wont kill it at idle if it doenst run long like that.