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Discussion Starter #1
Hi all,

A friend of mine is buying a 97 Cougar from his mechanic. Car has only 50K miles. Friends isn't sure if it's the 4.6 or 3.8 engine yet. His mechanic says that the timing chain broke and the valves are bent, so he has to repair it before selling it to him. His mechanic says there's also a rough idle he has to fix.

We're wondering how all this could happen on a 50K mile car, so I told him I'd do some checking. I'm leery about all this, but my friends wants the car.

QUESTIONS: Are the 4.6 and/or 3.8 engines interference engines, where the pistons will collide with the valves if the chain breaks or slips? And can the engine even run (the rough idle) if the chain has slipped or broke?

Thanks for any feedback & info.
 

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Yes on both, although a one-tooth-jumped timing chain may not cause problems on the 3.8.

On the 4.6, since it's overhead cam, it's possible the tensioner failed due to age and lack of lube (if it's only got 50K miles, it's not been run that much, so it's not been kept lubricated!), so I'd lay odds on it being a 4.6 with that description.

Good news! If the mechanic has to do that work anyway, and it's a 4.6, it's prime for a PI head/intake upgrade!

RwP
 

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Discussion Starter #3
Thanks Ralph...I wasn't aware both engines were designed that way. On the point about it possibly not being lubricated well, now I'm wondering if the previous owner (an older lady) didn't do oil changes or other services, causing the chain lube problem. And if so, could this engine be a mess if my friend buys it.
 

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Run don't walk away from this car unless he's getting it for dirt cheap!

By dirt cheap I mean under a grand and even then I'd question the reliability of any repair work the mechanic might have done. Short of replacing the heads with PI heads, personally, I wouldn't want it.

How much is he paying for this car?
 

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I wouldn't stop at just a head swap. If it really did break a timing chain or jump time after only 50k miles, who knows how neglected it was, and what the rest of the bottom end looks like. I would say only buy the car if it is in absolutely perfect shape other than the motor, and if it is $1000 or less, and if you do buy it, swap a complete low-mile PI motor into it.
 

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Hi Trunk...he doesn't know the price yet because the mechanic wants to repair the engine first before pricing it.

Any feedback on what you'd suspect is wrong with the car?
I have no idea what's wrong with it.

I'd go with what MadMikey said there - just swap the whole engine for a PI motor.

There's a well written how-to article here at TCCoA. Here's the link:

http://forums.tccoa.com/showthread.php?t=94152
 

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Discussion Starter #8
I wouldn't stop at just a head swap. If it really did break a timing chain or jump time after only 50k miles, who knows how neglected it was, and what the rest of the bottom end looks like. I would say only buy the car if it is in absolutely perfect shape other than the motor, and if it is $1000 or less, and if you do buy it, swap a complete low-mile PI motor into it.
I'm not sure he'd want to do the PI upgrade due to cost. And, if this engine suffered a failure this early, due to theoretical poor maintenance, there's probably more issues that are waiting to jump out. It takes real effort to bust these 4.6s, so I'm curious to know what happened.

It's going to be a car for his college going son, so putting too much money into it, plus the purchase cost, might not work for him. These cars are bulletproof though...so it might pay off in the long term as reliable transportation once it's squared away.
 

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Just be aware that due to age (hey, it IS 16 years old!), all the suspension needs to be gone through.

This is mostly a DIY level job, though, especially if you don't mind the Monroe ride (Monroe, Raybestos, and SACHS all list "strut kits" for the front, with the shock and a new spring premounted with all new mounts).

RwP
 

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I'd take the all plastic OEM POS over the Dorman POS below it
I have an all plastic PI intake off a 2001 Crown Vic - from what I understand, these were never a problem, right?
 

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I have an all plastic PI intake off a 2001 Crown Vic - from what I understand, these were never a problem, right?
Wrong! The all plastic intakes all are prone to cracking. Actually even the ones with the aluminum crossover are prone to cracking, just in a different place. What would really concern me about an all plastic intake is that it means it is at least 13 years old, and at that age it is on borrowed time whether it has the aluminum crossover or not.
 

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Yup! The ones with the aluminum crossover crack in the plastic right underneath the crossover, or at the rear coolant outlet that goes to the heater core. Basically they didn't solve the problem, they just moved the failure point. If your intake hasn't been replaced since the late 90s, I would just be prepared to replace it soon.
 

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Discussion Starter #16
That's interesting. In all the posts I've read over the years, I've never read one about the manifold with the aluminum crossover from Ford failing. Dormans...I hear about them failing all the time, though.
 

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I've personally only seen it happen to the Dormans but it does happen. The integrated gaskets under the crossover mean there's a thin layer of plastic inside the port shaped O-rings and after a while they can break inward allowing coolant out the gasket between flanges. OEM intakes have that weak point only on the crossover side though and IMO it's way less of an issue. Dormans crack at both ends, and usually simultaneously, as they have those O-ring gaskets on both sides of the flange and leave very little material to hold it together and can be much more catastrophic when they go.

The heater hose piece can be fixed fairly easily with a tap and hose barb, and the ones I see that are broken always seem to have aftermarket straight hoses hooked to them. No doubt the tension from the bent hoses probably contributes to their failure.
 

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The father-in-law had his OEM all-plastic intake replaced under the recall in the early 2000s (not sure on exact date) and his failed about 3 or 4 years ago - exactly as Mikey described (the plastic under the crossover where it meets the head) cracked and leaked. The factory replacement npi I pulled off my car in 2009 had signs of major corrosion there as well, plus it had the original heater outlet barb sawed off and replaced with a metal one like Matt described.
 

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FYI, here is when I found out the problem existed on the aluminum crossover intakes as well. Since that time, I have also seen 2 others fail in the same way, and 2 with the cracked heater hose outlet.

http://forums.tccoa.com/showthread.php?t=136730
 
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