Engines with questionable designs

[Snagglefoot]

I was looking at the 3.5 liter DOHC ford engine as found in the Ford Fusion. People on the Fusion forum were complaining on the high cost of a water pump replacement and that some of these water pumps can fail at 85,000 miles. Ford books 10 hrs for the repair. The pump is nestled underneath the timing cover, not over top it like the older Vulcan 3.0 V6.

What other engines have quirky designs that would take an ordinary component repair and turn it into a 10 hr marathon?

 

[maxdustington]

VW V10 TDI with the timing belt at the rear of the engine. 800ft/lbs of torque though 535 ft/lbs.

Ford PSDs that need to cab taken off for serious work. I think this is bad for a DIY but great for a dealership mechanic, because they can probably yank the cab quickly with practice.

 

[Chris142]

The northstar has the wp inside a housing and you need a special tool to unscrew the WP from the housing. You cant do it any other way. The Northstar starter is under the intake manifold too.

 

[Snagglefoot]

On the 3.5 DOHC Ford, some shops drop the engine with the trans and front wheel drive train out the bottom in one piece. They usually install new timing chains as well.

 

[StevieC]

The Chrysler 2.7L had an internal water pump that would fail all the time. It was a real pig in models that aren't RWD. RWD is still 5 hours and this video shows what's involved. Have to take the timing chain off. In the FWD models it's a royal pain because there is limited access with the wheel well in the way.

https://www.youtube.com/watch?v=z_QrXR2jcb8

 

[bullwinkle]

Not an engine, but the cradle design on the Transit that has to come off to do transmission, TC, or RMS repair is pretty horrible-bolts into the body that break off on removal & require replacing all kinds of expensive dealer only parts.

 

[maxdustington]

Originally Posted by StevieC
The Chrysler 2.7L had an internal water pump that would fail all the time. It was a real pig in models that aren't RWD. RWD is still 5 hours and this video shows what's involved. Have to take the timing chain off. In the FWD models it's a royal pain because there is limited access with the wheel well in the way.

https://www.youtube.com/watch?v=z_QrXR2jcb8
I watched the vid, the location of the water pump is insane.
2.7 sludge monster living up up it's repuatation! LOL

 

[StevieC]

They did fix the sludge problem which affected the first generation of that engine but they were always hard on oil as the varnish shows, and leaking coolant into the oil is never a good thing when the water pump fails.

 

[Dave Sherman]

Originally Posted by Snagglefoot
I was looking at the 3.5 liter DOHC ford engine as found in the Ford Fusion. People on the Fusion forum were complaining on the high cost of a water pump replacement and that some of these water pumps can fail at 85,000 miles. Ford books 10 hrs for the repair. The pump is nestled underneath the timing cover, not over top it like the older Vulcan 3.0 V6.

What other engines have quirky designs that would take an ordinary component repair and turn it into a 10 hr marathon?

Ooh, that would be the 3.6 V6 I had in my 2010 Traverse. Okay, maybe it shouldn't be an "ordinary" repair, but thanks to poor design, the 3 timing chains on 2009-2010 Traverses were prone to wearing out and needing replacement when the valve timing errors popped up. Can't be done with the engine in the vehicle, it has to come out. How does it come out? Not through the hood, but through the underside. That means disconnecting the propeller shaft, steering shaft, brake lines, A/C lines, upper struts, transmission cooler lines, shift linkage, and dropping the whole front frame; engine, transmission, and all. That's on top of the usual things to disconnect from the engine like exhaust, fuel lines, coolant hoses, and wiring harnesses. When it all goes back together, you have to bleed the brake system, do a front end alignment, and evacuate and recharge the A/C. Typically a $3000 or more job, and I've heard some folks have had to have them replaced more than once.

 

[BigD1]

Any V design that still relies on sealant to seal the ends of the lower intake to the block. Must be gasket impossible. Installing the lower intake, and one wrong bobble it will leak oil.

 

[emmett442]

Originally Posted by Chris142
The Northstar starter is under the intake manifold too.


I actually like this design. It keeps the starter out of the elements and thus failure seems awfully rare in comparison to others. At least, in the great white north. Salt and road grime are [censored] on starters and their cables.

Besides, when it DOES have to be replaced, it's not as bad as it seems. The N* intake is dry and comes off EASY. No coolant to mess with. I think I'd rather remove a N* intake than work with a rusty and crusty starter between a exhaust manifold and frame rail as in a conventional design.


Also, the Northstar isn't the only one. It's become more common as the years have rolled on. Don't the Toyota UZ V8's also put the starter in the same spot?

 

[maxdustington]

Originally Posted by emmett442
Besides, when it DOES have to be replaced, it's not as bad as it seems. The N* intake is dry and comes off EASY. No coolant to mess with. I think I'd rather remove a N* intake than work with a rusty and crusty starter between a exhaust manifold and frame rail as in a conventional design.
No gaskets to screw up and no chance of junk getting into the intake ports in an external location. In the engine is probably better for a pro mechanic, harder for a DIY.

 

[jeepman3071]

Pretty much any modern diesel with emissions controls.

 

[WyrTwister]

From what I read , engines with a timing belt often have the WP under the timing cover .

Luckily , our 2015 Chevy Sonic 1.8i has the WP on the outside .

 

[SwampSurvivor]

It took me 5 hours to replace the lower radiator hose on my F350 last year. The lines going to the cooler have the spring clamp ends inside the crossmember. Can't get to it with any sort of wrench or pliers, even the tool made for spring clips.

 

[4wd]

Originally Posted by WyrTwister
From what I read , engines with a timing belt often have the WP under the timing cover .

Luckily , our 2015 Chevy Sonic 1.8i has the WP on the outside .

 

[4wd]

The belt on our 2007 Pentastar had a 100k PM … to do the water pump at the same time was $70 more … no brainer

 

[exranger06]

Originally Posted by WyrTwister
From what I read , engines with a timing belt often have the WP under the timing cover .

Luckily , our 2015 Chevy Sonic 1.8i has the WP on the outside .

Big difference between a timing cover on a chain-driven engine and one on a belt-driven engine. Belt-driven has a plastic cover that's designed to be at least somewhat accessible and easy to remove, AND does not have to seal in any oil or coolant. Timing cover on a chain-driven engine has to prevent oil and usually also coolant from leaking out and are generally much more difficult to remove. You also rarely have to replace a water pump on a belt-driven engine due to failure, since they (should) always get replaced when you replace the timing belt so you don't have to do all the labor again. As a result, they usually get replaced long before they fail.

 

[demarpaint]

Originally Posted by 4WD
The belt on our 2007 Pentastar had a 100k PM … to do the water pump at the same time was $70 more … no brainer


2007 Pentastar. Is that a typo?

 

[redhat]

Hows about every Gen IV and Gen V LS/LT motor with AFM and DOD lifters. Junk.

And I love LS.