How long does it take once an IMS starts to go?

[Skootnasty]

Originally Posted by southernstar

Perfectlap, you would only get more contamination from a dual-row bearing if it is failing - something it does much less often than a single-row (less than 1% versus 8-10%). Nevertheless, you and Homeboy make a strong case for replacing the single-row bearing as a prophylactic measure.

Brad

I am not attampting to start an argument. That being said, any orig. dual row bearings that are still installed in an engine is failing. The outer seal on the bearing has been sitting in oil for at least 13 years. That rubber seal has become hard and pulled away from the sealing surface. This has allowed grease to be displaced with dirty, inadequate oil. This has resulted in *SOME* degree of metal wear. The amount of wear...... who knows with out taking every one that is left out of the engine and measuring every ball. It is very true that two rows of balls does equal a stronger bearing in respect to breakage. However, do not fool yourself, those seals are compromised and the balls inside are losing metal in larger quantities than the serviceable single row replacements.

Skoot

[pothole]

Low values have nothing to do with the bearings failing. It's that they built loads of them. Now they're getting old but they haven't reached classic status.

Imagine a scenario where the bearing problem didn't exist and you assumed values of early 986s were higher. Well, you'd have to push prices up for all newer Boxsters, too. Because if you push up the value of an early 986, it becomes worth the same as a late 986. So adjust that up, too. Then it overlaps with 987s. Etc etc.

If you look at used values, the late 987s with 9A1 and no IMS are also depreciating and there's a pretty consistent slide in values as go down through the older models. There's no massive, massive drop in value when you go from an early 987.2 to a late 987.1. Yes, there's a gap, but it's just a normal gap given the 987.2 is the newer model.

There's just no space in the value hierarchy for early 986s to be worth significantly more than they are.

People tend to forget these are mass market cars. They built loads of them, so supply is strong. And most people who own them are not enthusiasts who spend the time to learn about this stuff.

Moreover, once you get to proper classic status, these sorts of issues completely fade away. People don't value 60s Ferraris on the basis of reliability.

[Overdrive]

Originally Posted by pothole

Low values have nothing to do with the bearings failing. It's that they built loads of them. Now they're getting old but they haven't reached classic status.

Imagine a scenario where the bearing problem didn't exist and you assumed values of early 986s were higher. Well, you'd have to push prices up for all newer Boxsters, too. Because if you push up the value of an early 986, it becomes worth the same as a late 986. So adjust that up, too. Then it overlaps with 987s. Etc etc.

If you look at used values, the late 987s with 9A1 and no IMS are also depreciating and there's a pretty consistent slide in values as go down through the older models. There's no massive, massive drop in value when you go from an early 987.2 to a late 987.1. Yes, there's a gap, but it's just a normal gap given the 987.2 is the newer model.

There's just no space in the value hierarchy for early 986s to be worth significantly more than they are.

People tend to forget these are mass market cars. They built loads of them, so supply is strong. And most people who own them are not enthusiasts who spend the time to learn about this stuff.

Moreover, once you get to proper classic status, these sorts of issues completely fade away. People don't value 60s Ferraris on the basis of reliability.

Exactly. Someone else gets my drift.

[shadrach74]

Originally Posted by Skootnasty

I am not attampting to start an argument. That being said, any orig. dual row bearings that are still installed in an engine is failing. The outer seal on the bearing has been sitting in oil for at least 13 years. That rubber seal has become hard and pulled away from the sealing surface. This has allowed grease to be displaced with dirty, inadequate oil. This has resulted in *SOME* degree of metal wear. The amount of wear...... who knows with out taking every one that is left out of the engine and measuring every ball. It is very true that two rows of balls does equal a stronger bearing in respect to breakage. However, do not fool yourself, those seals are compromised and the balls inside are losing metal in larger quantities than the serviceable single row replacements.

Skoot

My single row bearing was removed @51K and 11 years. Rubber was not hard and bearing had no visible signs of wear or play. It was as tight as the LN piece that replaced it. Do you think I'm in the minority? I'm more inclined to think that Homeboy's car is in the minority.