[Daytrepper]

Ive had many questions about 2.7's and their lifespan, and hi-jinks, so here is some info about the causes and effects of their failure, and how to keep them alive, at least what Ive found to be successful.

Heres what I have found over the years of working on these things...dont believe everything you read online... the thing about them, is most are people that make assumptions, and really have no true idea of what was going on...im not saying the 2.7 is an innocent engine either..so dont get me wrong...hehe.

99.99999% of all 2.7 failures are caused by the water pump. They are not caused by poor maintenance, although that can be a major contributing factor in speeding the process along.

1. Sludge -- Sludge is caused by coolant leaking internally into the engine, from the water pump. The pump begins seeping, and being an internally mounted pump, it goes right into the oil, via the timing chain housing. Over time the coolant mixing with the oil causes the sludge. This problem is exacerbated by poor maintenance of the PCV system, as it becomes plugged or inoperative due to buildup in the hoses (weak design here), and the hoses collapse, or the PCV valve itself seizes closed, and the engine cant breathe. The result, general moisture/vapor from intake air, condensation, combustion, etc, has no where to go, and more moisture = more sludge. Sludge sort of acts like atherosclerosis, slowly filling in and plugging oil galleys and passages. In frequent oil changes make this even worse. Now....sludge doesnt always happen...it depends on where the water pump decides to leak. They dont always leak into the oil when the bearings start to fail. Sludge can also clog and starve the oil pickup and bearings, and cause a knock, before the water pump ever has a catastrophic failure. In some instances, sludge formation from a bad water pump has caused seizure/knocking before the water pump leak is found. There are a few other causes of sludge, but as far as the 2.7 is concerned, this is the most relevant.

2. Water pumps -- the water pump is a poor design, there is no doubt about that. It has been shown that even 3.2/5 engines have water pump issues, at about the same mileage, but are much less failure prone, due to the use of a timing belt, amongst other factors. In the 2.7, the water pump has a high amount of load on it, from a very long and heavy timing chain, along with the vibration of operating 4 camshafts at once. It is simply not heavy enough to handle the load for an extended period of time (100,000+ miles, years, etc)...so the bearings and seals fail, resulting in leakage into the engine, and outside thru the weep hole. When the bearings fail, the timing chain comes off, can come thru the valve cover or cause damage to the engine block, and with the cams and crank rotating free, pistons hit valves, and they bend. Catastropic in most cases, and the engine is scrap metal. Just a few minutes of inspection for a bad water pump can completely prevent this.

3. Small oil passages -- this is a myth...the oil circulation is actually pretty decent in these engines, it is the sludge that causes problems there. One is the timing chain tensioner, since its operated by oil pressure, and one of the last components to get oil, it is especially sensative to sludge buildup, so if sludge is occuring, then it will not be able to maintain good tension on the timing chain. Usually by this time, the bearings are beginning to fail in the water pump...

4. Rebuilding a 2.7 -- I see many people attempt to repair these engines when its too late. When the bearings or tensioner fail, or begin to fail in the water pump, and the timing chain starts rubbing the front cover, or chewing on metal parts, these parts end up in the oil pump, and into the bearings. All too often I'll see one that has just had a brand new chain put on, and is knocking a week later. Oil pump/pickup, and oil pan must be removed and thoroughly cleaned, (or oil pump replaced) if this has happened. Its also a very good idea to remove the rod and main bearing caps and inspect for metal shaving damage.

4. Detecting it before it gets bad...the first symptoms of water pump problems in a 2.7...unexplained coolant loss (no external leaks), and no heat at idle. Along with that, any abnormal ticking/grating, or metallic noises, that are not consistent. If you are experiencing this, get it checked ASAP, in fact, dont drive it until you do. There is a weep hole that the pumps are supposed to leak from, which is located behind the alternator to the bottom left of the thermostat housing/lower radiator hose, but the problem is, it often does not leak while the car is not running, so the average person will never know it.

5. Keeping the 2.7 alive -- the rest of the 2.7 is actually a very tough design. They are built very well, except for the water pumps...hehe...to keep them alive, full synthetic oil changed every 4,000 miles from day 1, water pump changed every 75,000 miles, or checked for leaks and change as needed. Update to the new style timing chain, tensioner, and water pump (heavier and less problems), if you have an older engine. Change PCV valve and hose once every 2 years, or if the hose becomes mushy. Several 2.7s locally have had this maintenance regiment, and are still alive and well, one pushing 350,000 miles, and another well over 200,000. This is proven.

The 2.7 may be a good little engine, but the problem is, it is sensitive. The average every day car owner doesnt check under the hood, or doesnt know how to check under the hood, or know how to look for problems. Many repair shops/ and even some dealerships know little about the specifics of these engines, nor how to keep them alive. Many just do not know its ins and outs, so they are not able to keep it alive.

So, 2.7s are a pain in the ass, but if you know how to keep them happy, they will last a very long time, and it will save you tons of money on repairs, or an engine swap. Of course upgrading to a 3.2/5 is a huge improvement, but not everyone can afford it, or is willing to have it done, when a little more attention to their 2.7 will keep the car running just fine.

Just for grins, here is a 2.7 with 160,000 miles on it, maintained with Royal Purple synthetic oil, (excellent maintenance by LittleRedTrep), you can see it looks very normal inside. Also note how close the timing chain runs to the front cover/engine block. That will give you an idea of how little play/lack of tension it takes to get it rubbing something it shouldnt be. This engine still runs like a top, although transplanted into another trep...and is driven daily.....

 

[dodgeguy]

Thank you, very helpful do some water pumps fail before 100,000 miles or is it mostly after 100,000 miles?

 

[Daytrepper]

Thank you, very helpful do some water pumps fail before 100,000 miles or is it mostly after 100,000 miles?

Average is about 80,000 miles, when they start leaking. Some of it depends on how they are driven, engines with more highway miles tend to last a bit longer.

 

[MitchQ2]

I have 114K on mine and I dont have any signs that the pump is going bad. Do they all go bad for shore? Maybe my time is coming soon if so.

 

[Duds]

I had 83,000 on an excellently maintained 2.7 and the water pump started to leak. Sometimes it would leave a puddle on the garage floor, next day it would not. I quit driving it immediatly and had it towed to Dan's place. There were no warning signs. And from what I heard from some, the water does not always leak onto the floor. Rather into the oil. Regular checks of water and oil levels are critical.

 

[Squilliam]

Finally. Thank you Dan. A thread that DOESN'T bash the 2.7. Very good info for those who are ignorant of the 2.7's TRUE design flaws and not this bull that you see on these websites that average Joes ***** on whenever they don't even know the difference between a lugnut and gascap. This thread should be stickied!

 

[thepenguin40]

Average is about 80,000 miles, when they start leaking. Some of it depends on how they are driven, engines with more highway miles tend to last a bit longer.

Daytrepper, is that 80K estimate based on the older water pump design or the new one? Or does it even matter. I ask because I just rebuilt our 2.7 which included the oil pump, water pump, tensioners, chains, guides and a new bottom end.

With only 1K miles on the new motor we have a ways to go before I start to worry about it but having a baseline is good.

 

[peva]

Good info., Dan!

I have 114K on mine and I dont have any signs that the pump is going bad. Do they all go bad for shore? Maybe my time is coming soon if so.

My sample of one went 207k miles before I replaced chain or water pump. Phil (Va3ux) didn't change his until either 212k or 217k, I forget which. So there's two samples. But apparently ours are exceptions. Phil's water pump actually started coming apart, but he stopped the engine in time to avoid damage. Mine didn't have any problem when I replaced it - Phil's experience scared me, so I did it. Strangely, my old pump turned silky smooth by hand after I removed it, had zero play in the bearings, and had *no* signs of leaks - not even residue anywhere. Weird (in a good way).

Mine does get driven daily (5 days a week) 80 miles a day, which goes along with what Dan was saying about highway miles being good for them.

They had come out with the re-designed chain, pump, and sprockets just before I did mine, so I feel fortunate with that. I'm at 226+k now - still running like a top (I did replace the valve stem seals and oil pump at the same time).

Oh yeah - oil pump - that reminds me. I remember reading that they increased the capacity of the oil pump (maybe in 2000?) due to some supposed failures of one of the crank or rod bearings in particular? Anyway - yeah - I could tell that the replacement oil pump I put in was bigger (rotor was thicker, maybe some diameter increase too.

Comments on the oil pump capacity increase Dan? Was there some bearing failure problem with the original pump that you've seen?

 

[Intrepidation]

Great writeup!

 

[Torontofirecaptain]

Good write up Dan, sound advice on maintaining the engine - in fact, all engines-, too.
One thing I was told by a Chrysler tech, was that the oil pick up tube sits too low to the bottom of the pan, and this can cause a problem in colder areas, especially on start-up, as the pump can cavitate briefly, sending air bubbles into the oil galleries.
Not good it is in fact does this.
He told me the shop he is foreman of raised the pickup by 1/4" to cure cold morning engine knock.
What's your take?

 

[Daytrepper]

Daytrepper, is that 80K estimate based on the older water pump design or the new one? Or does it even matter. I ask because I just rebuilt our 2.7 which included the oil pump, water pump, tensioners, chains, guides and a new bottom end.

With only 1K miles on the new motor we have a ways to go before I start to worry about it but having a baseline is good.

Both, I would use the advice on the newer and older designs, although the newer design is tougher, ive seen both fail.

Good write up Dan, sound advice on maintaining the engine - in fact, all engines-, too.
One thing I was told by a Chrysler tech, was that the oil pick up tube sits too low to the bottom of the pan, and this can cause a problem in colder areas, especially on start-up, as the pump can cavitate briefly, sending air bubbles into the oil galleries.
Not good it is in fact does this.
He told me the shop he is foreman of raised the pickup by 1/4" to cure cold morning engine knock.
What's your take?

Thanks Ross, and that is true on the oil pickup. Sludge can collect around it as well, and that makes it much worse. Chrysler started using a re-designed oil pickup around 01-02ish to combat this issue. They made it larger in diameter, and made the bends not as sharp, and it sits alittle higher off of the bottom of the pan. Jasper Engines actually started this in their remanufacturing process first.

 

[cdmccul]

Nice Write-up, Dan... +1 for Sticky!

 

[Daytrepper]

Thanks fellas, Stuck like a pig! Hopefully this will help a few 2.7s live longer.

 

[TrepCruzin]

Right on Dan.....Once I'm done with my motor switch over, I'm taking the 2.7 from this Trep and putting it into another LH with a blown motor.

 

[jasonJ1969]

Thanks for sticky-ing this. i get frustrated every time someone goes on about tiny oil galleries and whatnot.

I check my oil and coolant levels once a week religiously as well as my PCV system. Though I am fairly sure the chain has been replaced before I got it, and I'm 98% sure this isn't even the original engine, I will most likely put a new updated pump and chain set in it when the temps warm up. Or I will at least pop a valve cover off and see if it has the new style chain which would be nice. There is orange high temp RTV under the valve covers and front cover, so I can imagine an engine was acquired, and the chain/pump replaced before install, but who knows. I have only put about 13,000 miles on it since I got it in 07. I have also never heard a single weird tick or knock, even in 9 degrees below zero startup, except for the loose torque converter bolts fiasco. I change the oil every 6 months, I never reach 3000 miles on each interval, and the oil is always pretty clean at change time.

Speaking of PCV system, I never see it mentioned here but once a winter I remove the curved box section of intake just prior to the elbow that connects to the throttle body and empty a ton of water out of it. I also clean out both PCV hoses and make sure the valve is 100% awesome. This isn't needed in the summer because I don't idle the engine long in the summer. In the winter though, if it is 3 degrees out, it runs about ten minutes before I drive it. That is because I leave my driveway, go 400 feet, then get onto a 65 mph highway. Don't want to do that on a bone cold engine.

I doubt I am the only one who has water collect in that intake section, though maybe it evaporates so I don't actually have to worry about it, but still. I have never seen anything like this in any other vehicle. It's like they designed this section specifically to collect water.

 

[peva]

...Oh yeah - oil pump - that reminds me. I remember reading that they increased the capacity of the oil pump (maybe in 2000?) due to some supposed failures of one of the crank or rod bearings in particular? Anyway - yeah - I could tell that the replacement oil pump I put in was bigger (rotor was thicker, maybe some diameter increase too.

Comments on the oil pump capacity increase Dan? Was there some bearing failure problem with the original pump that you've seen?

...

 

[03SE]

daytrepper.. i have a 03 SE, in your post you said to"update to newer timing chain, tensioner, and water pump if you have an older engine". Is the 2.7 in my car an older model? If so, what are the part numbers i should get for the timing chain, tensioner, and water pump? if it matters, i have about 60k on the clock.

 

[peva]

daytrepper.. i have a 03 SE, in your post you said to"update to newer timing chain, tensioner, and water pump if you have an older engine". Is the 2.7 in my car an older model? If so, what are the part numbers i should get for the timing chain, tensioner, and water pump? if it matters, i have about 60k on the clock.

There was a new chain design (different pitch) with new cam sprockets and water pump for compatibility that was just starting to be supplied as the replacements for our cars about a year ago when I did my chain and pumps (water and oil). I don't know if that's the new design that Dan was talking about. I suspect that they are the design used in the LX platform 2.7, and were not sold before a year ago to go into our cars, though they are backward compatible as my engine (a '99) proves.

If Dan was referring to something different as far as a newer design, he can explain. But if it's the new design that I'm talking about, then I believe your engine would have come with the older design - I could be wrong. Perhaps the newer design did in fact come on later year LH's, and only recently were starting to be sold for use in the earlier engines. Oh Dan . . .

 

[McGruff]

I have a 02 Interpid with a 2.7 its at 74K and I had to change the thermostat 2 years ago. My problem is everytime it rains or it gets cooler outside my check engine light comes on and stays on. and dont understand why its just during the rainy or cooler seasons I live in Florida so during the summer it never comes on?

 

[newbe04]

There was a new chain design (different pitch) with new cam sprockets and water pump for compatibility that was just starting to be supplied as the replacements for our cars about a year ago when I did my chain and pumps (water and oil). I don't know if that's the new design that Dan was talking about. I suspect that they are the design used in the LX platform 2.7, and were not sold before a year ago to go into our cars, though they are backward compatible as my engine (a '99) proves.

If Dan was referring to something different as far as a newer design, he can explain. But if it's the new design that I'm talking about, then I believe your engine would have come with the older design - I could be wrong. Perhaps the newer design did in fact come on later year LH's, and only recently were starting to be sold for use in the earlier engines. Oh Dan . . .

good info peva... if we can get a confirmation on this would be cool... also, when your going to the dealer to get parts. are they going to automatically give you the "new" set up or the old? P/Ns? also, when switching to new design, do you need new sprockets? because you said it was a different pitch. thanks!