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2.7L Done For?

3K views 17 replies 9 participants last post by  rusty69 
#1 ·
Hi All,

This forum is awesome and has a wealth of information. My son was given a 2006 Dodge Stratus from a family member. The car wasn't running but they thought the starter and/or battery was done for. We replaced both after testing the starter and finding it faulty. The car started and ran good, so we replaced all the fluids and filters. Well, he drove it around town a day or two when it died. We towed it home and noticed the oil on the dipstick looked a little like a chocolate milkshake. So, we drained the oil and it looked like a chocolate milkshake. We read the forums here and noted the information regarding the water pump leaking into the oil pan.

We ordered a new water pump and timing chain set. Which brings us to today. We completed a cylinder compression test before taking off the intake manifold and valve cove. Compression was good. Under the valve cover was a lot of oil sludge. Is this engine done? I attached photos showing the oil sludge.

Any opinions are appreciated.

Thank you,

Joe
 

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#3 ·
I'd say "no." Mine was worse. You just have to clean it the best you can, make sure your sprays, tensioner weep hole, and head drains are open. You can get some B-12 Chemtool spray and a nylon toothbrush and clean that stuff out then run some wire (e.g. coat hanger) thru the drains. Spray plenty of spray around to push all that crap into the pan then spray some in the front of the pan with the drain open to make sure it all comes out. There are sprays in the back of the heads (in little holes drilled in what look like freeze plugs) that may need to be poked open plus one on each rocker. Chemtool is your friend. Also when you take your tensioner out you can jack some chemtool into it a few times (then I soak it while doing the rest of the job).

Before I do the final assembly I do a test run by just sticking the plugs/coils back in, tacking the plenum down, hooking up the wires, dropping the radiator in (to hook up the tranny cooler lines to it) and slapping on the ducting to the airbox. I also put a little shield of aluminum foil over those rear sprays otherwise they'll soak your hood and engine compartment in oil.

Make sure you have good oil pressure with this test run cuz your pickup tube could be plugged with sludge or your oil pump shot.

Before I do my test run, I fill my oil filter with oil and put it on, then put the proper amount in the crankcase (filling from the front cover area) then pull the plugs and crank the snot out of it to make sure the tensioner is fully extended (should be solid when you try and pry on the top of the right hand guide). Also, don't forget to put in a cam chain block so if the sludge does return to block your tensioner your timing doesn't jump and grenade your engine.

During your test run make sure you don't hear any rod knock, cuz if you do, now is the time to fix it. Its not that hard to pull the pan (and you can then clean it and the pickup tube) and replace the rod bearings usually before any damage has happened to the journals (make sure and plastigage them). I've heard an upgrade is to use the deeper and baffled 2009 pan and pickup tube which helps prevent the engine from starving for oil during spirited cornering when it might be as little as 1/2 quart low. What I'm doing is relocating the oil filter into the battery box and putting on a bigger PH8A style one and reducing my battery size by using an ultracap array and a gel cell UPS battery (with a few other widgets to limit the current transfer between them plus a disconnect in case I'm going to leave the car for a long time so the caps don't discharge the battery).

I'd only run 0w-40 Mobil1, perhaps with a little chemtool (maybe a half a cup) to keep that sludge moving on into the oil filter and change it out every couple thousand miles for a while. Also make sure your PCV system is thoroughly clear and the check valve is working good (again with Chemtool).

Oh, another thing I did was to slather both sides of the water pump gasket up with RTV red and just finger tighten it on overnight then come out the next morning to torque it. I don't want to take ANY chances of that gasket leaking.

Make sure and use HOAT anti-freeze in the system to slow down the erosion of the water pump seal (and help seal up any microscopic leaks the system may come up with). Actually I pressure tested it thoroughly overnight before I reassembled it because overheating is terrible for these engines.

If you've got a good compression test (or as I prefer, leakdown test), then you should still be able to get plenty of miles out of it.
 
#4 · (Edited)
I agree, except;

I dont recommend trying to clean and remove the sludge you see. If you start to clean and loosen that sludge----which you'll never get it all---without a complete tear down and hot tank clean---you'll have sludge particles loose suspended in the oil, and this can damage oil pump, bearings, and plug small oil passageways. The filter will not catch them before they have a chance to do damage. Cleaning agents in the engine if not properly rinsed out will damage bearing surfaces as well----again, the only real way to clean is a complete tear down and hot tank treatment.

Do not attempt to clean the timing chain tensioner, replace it. It is spring loaded; so if it is properly activated there will be no concern of the chain losing tension. Once the engine starts and develops oil pressure that pressure will maintain the chain tension.

I would remove and clean the oil pan, and oil pump pickup; if there is sludge in the oil pump pickup, replace it.
 
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#10 ·
there are sprays at the back of the head and in each of the rockers that may need to be opened up that can be plugged with sludge. Rod bearing problems after cleaning sludge are probably due to them plugging up the oil filter and causing it to bypass. It would definitely be a good idea to relocate the oil filter into the battery compartment (after relocating the battery or replacing it with something much smaller like an ultracap array) and get a much larger (PH8A size) one then changing it frequently (perhaps even more frequently than the oil). I seriously doubt the sludge is getting into the rod bearings thru splash lubrication. Everything you're describing would be coming from the filter getting plugged and bypassing. Sludge isn't abrasive. It just plugs things and then can cause starvation. One could probably pull the filter every couple hundred miles and rig up an apparatus to back flush it with solvent to see how much gunk got in there then keep putting it back on until the chunks of sludge stopped coming out then install a new one for that matter. I've had a number of boats with serious fuel varnishing and sludging problems and the battle can be won with cleaners and filters. Not easy, but generally not nearly as difficult nor expensive as a rebuild (especially if you're starting with a motor with good compression and oil pressure to begin with)
 
#14 ·
Sludge is 100% abrasive. It is made of particles of carbon and other contaminants, it is similar to sand. It will definitely cause harm thru splash lubrication. I've seen it many times. You can tell when you pull an engine down whether it was starvation, or oil contaminant wear. In all of those engines, the few that I cut the filters open on, none were to the point of a bypass. You have to consider as well, before the sludge enters the oil filter, it goes thru the pump; and those fine particles will wear the pump faster, and reduce oil pressure.

However you want to spin it, fine sand like particles suspended in engine oil are not good, and not worth the risk. If its already there, let it be.
 
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#11 ·
Wtf is it with you wanting to relocate the oil filter on the 2.7 ? It's in a great location as is and I for one used to run the larger filter in it's original location (no issues). Eventually that engine met its end when the primary chain tensioner failed.
 
#12 ·
I've destroyed 2 larger filters with it in the stock location (once on a curb before I remembered not to pull all the way up when parking and once on an unmarked speed bump) and my girlfriend destroyed one on an unknown hazard which she didn't notice before destroying the rod bearings and welding molten aluminum all over the journals which we were in the process of removing when the car was run over in a California wildfire, so quite literally not relocating the filter caused the utter destruction of the car.

(IDK why files won't attach here from either chrome nor edge so here's google drive links)

https://drive.google.com/open?id=1jEQdXmHg03usnDYD_zwXifJeUvsfgkim

https://drive.google.com/open?id=14st1m_1APQNwgTmq2Qmnren2rNcUqG1O
 
#13 ·
Good discussion on sludge but I don't think it matters much as the OP seems to be a "One Hit Wonder" like many new posters! Hasn't replied or posted since his original post. heh
 
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#16 ·
When I think of “sludge”, I think of the brown/black baked-on/burnt oil residue, which turns to abrasive particles when mechanically broken up. The OPs primary problem is a soapy water and oil mix which, though not a good film-forming lubricant, doesn’t break up into gritty particles.
 
#18 ·
my experience with sludge was in a 78 Magnum with a 400 BB. It can get past the oil pick up screen, in tiny little bits, and reconstitute into bigger pieces in tight clearance areas. In my particular case, they recombined into a bigger chunk which got pinched between the oil pump rotors, jamming the pump. The first time it sheared the oil pump drive shaft at the hex drive, so I put an M/P intermediate shaft in it, and it broke the oil pump the next time. So then I just, used stock shafts after that.
I tend to agree that it is nearly impossible to get every little bit of sludge out of a severely sludged up engine.
 
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