"Bulletproofing" a Chrysler 2.7, 3.2 or 3.5 liter V6?

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Bill Crowell

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A friend of mine has one of these engines sitting disassembled in his shop for the usual reason: the internal water pump failed, coolant got in the oil and ruined it.

Looking at the block, crank, rods and pistons carefully, this looks like it was basically a nicely-manufactured engine. The block casting looks very nice and the crank, rods and pistons look like they were made of good materials and well-machined.

So I got to wondering if you have ever heard of anybody who knew how to "bulletproof" one of these engines so the water pump wouldn't fail again, and if so, how did they do it? Thanks.
 
The 3.2 and 3.6 does not have the water pump inside the engine. Very little problems with those other than the oil cooler leaking, usually from overtightening. Some early 3.6 engines had cylinder head guides that were to tight but that problem was addressed quickly. The 2.7.... That engine is a total pile of trash.
 
Every one of the 2.7 (and some 3.7 and 4.7s) engines turned to junk quick. They seemed very prone to sludge and had a knack for making milkshakes. I have never heard of any way to make the water pumps not fail to answer your question.
 
Thanks, guys, for correcting me on the 3.2 liter motor, and for the good information on the 2.7. Too bad, though, that there's no way to bulletproof it. What could the Chrysler engineers have been thinking when they designed the engine that way? Certainly they could have found the room for an external water pump located off to the side somewhere, like they did with the slant 6, if they had really wanted to. They should have realized that it would have the problems that it had.
 
Thanks, guys, for correcting me on the 3.2 liter motor, and for the good information on the 2.7. Too bad, though, that there's no way to bulletproof it. What could the Chrysler engineers have been thinking when they designed the engine that way? Certainly they could have found the room for an external water pump located off to the side somewhere, like they did with the slant 6, if they had really wanted to. They should have realized that it would have the problems that it had.

Chrysler isn't the only manufacture to do this. Other engines with overhead cams and chains use an internal water pump some just planned for a better pump failure than others. If the motors is in a front wheel drive (or AWD with a PTO), you almost have to pull it to replace the pump.

In the end its no more or less intelligent then an interference engine with a timing belt or chain.
 
Try and replace a thermostat in a 2.7 then you well know the engineer was on ******. It's just as stupid as the water pump.
 
Why would you want to waste the time? You'll still have a POS.
 
So did the engine have other problems besides the internal water pump? I was thinking it looked fairly nicely made, but I have been wrong once or twice before.

Insofar as bulletproofing a POS is concerned, why for example do so many people go to such trouble and expense in order to bulletproof the failure-prone engines on old Ford diesel trucks? Maybe because it costs so much to buy a new one these days? I think cars are starting to get that way, too. What used to be a POS is looking better as more time passes.
 
I drove an '06 Magnum with the 3.5L for 267,000 miles with nothing other than regular oil changes. I sold the car 5 years ago, and the guy that bought it is still driving it. I think that 3.5 was a great engine, and had good power and was reliable.
 
So did the engine have other problems besides the internal water pump? I was thinking it looked fairly nicely made, but I have been wrong once or twice before.

Insofar as bulletproofing a POS is concerned, why for example do so many people go to such trouble and expense in order to bulletproof the failure-prone engines on old Ford diesel trucks? Maybe because it costs so much to buy a new one these days? I think cars are starting to get that way, too. What used to be a POS is looking better as more time passes.
Because when each was new, with the Ford you had something that pulled "whatever" was put behind it. Same once it's been bullitproofed....although the only one that actually "needed" it was the 6.0. The 7.3 was already there.

In the case of the 2.7, brand new, they couldn't pull a greasy string outta a cat's ***. So, why on Earth fix that up? If you want something with a 2.7, have at it.
 
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Truly most failures on the 2.7 due to the water pump failure are due to the owners not paying attention to them. There are two weep holes in the 2.7. One near the thermostat housing and one at the back of the pump that exits in the air gap under the intake. Like most people now days maintenance is foreign to them so when there is a puddle under the car or the coolant is low they ignore it. Water pumps are going to fail. Most 2.7's go over 100k before it goes out as long as the proper coolant has been used in the engines. Changing it does suck though. The thing that usually kills the 2.7 is the timing chain tensioner failing and causing it to skip time and bend the valves. That can be prevented by installing a stop block. Melling MSB-02 Melling Tensioner Arm Stop Blocks | Summit Racing
Chrysler did redesign the water pump and timing set for better durability around 2008 which has extended the life of the components. In order to upgrade you need to change all the components (water pump, timing chain, guides and sprockets.)
 
The first run of 2.7 engine did not have large enough oil drain back hole in the cylinder heads. Also the PCV system was not adequate so the engine would sludge up badly. You would have to change the oil about every 2000 miles to keep it clean. Also they have a timing chain that looked like a small bike chain that would stretch bad enough to set camshaft timing codes. The later engines the cylinder heads, intake, and timing chain were all redesigned. It was better but still had the water pump leaking problem. Also you can not new use any of the updated parts on the older engine because when they changed the timing chain design they went from an SBEC to the JTEC engine controller and the camshaft sensors are not compatible. It will always have a cam/crank sensor out of sync. Ask me how I know about that one! If you see a 2.7 engine under hood my advice is close the hood and run away!
 
I drove an '06 Magnum with the 3.5L for 267,000 miles with nothing other than regular oil changes. I sold the car 5 years ago, and the guy that bought it is still driving it. I think that 3.5 was a great engine, and had good power and was reliable.
The 3.5 was a very good engine. Nothing in common with the 2.7 at all.
 
2.7s were bad for that.

Ive had luck with 4.7s. 1st one, 2002 ram, bought new, sold it at 140k. Second one was a 2002 Dakota, got it with 140k sold it with 220k. Daughters 2003 cherokee, she got it with around 150k...has 175k on it now. She just got back from New York with it.

Heres a 2002 i picked up as a spare...130k i think.

20190411_100513.jpg


20190411_100559.jpg
 
A friend of mine has one of these engines sitting disassembled in his shop for the usual reason: the internal water pump failed, coolant got in the oil and ruined it.

Looking at the block, crank, rods and pistons carefully, this looks like it was basically a nicely-manufactured engine. The block casting looks very nice and the crank, rods and pistons look like they were made of good materials and well-machined.

So I got to wondering if you have ever heard of anybody who knew how to "bulletproof" one of these engines so the water pump wouldn't fail again, and if so, how did they do it? Thanks.
No such thing
 
The 2.7 had gasket problems in the early years. Chrysler fixed it later. See allpar for more info.
The 3.5 is a good engine. A friend had one in a town & country mini van that went 170,000 miles, loaded most of the time. Still ran sweet until rust got to it.
 
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