roaniecowpony
Well-Known Member
Good advice. And given that the coupler is a $60 part (aftermarket only, from what I could find), a DIY guy could save almost all that cost you incurred.
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Line of oil on top of engine
- Thread starter ppfingsten
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roaniecowpony
Well-Known Member
This "decoupler" appears to be a sprag clutch. It locks the outer pulley to the inner shaft when driven in the normal direction, then allows it to spin freely in the other direction. So, if you replace yours, make sure you get one compatible for the JL application, which seems to have the alternator pointed pulley end to the aft of the vehicle and likely rotating opposite of more common installations. Otherwise, the pulley will just spin and the alternator won't be driven.
jjvincent
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I've seen a number of them fail. Seems that it used to be common on VW's then they must have figured it out. After that Chrysler seems to be taking up the slack where VW left off.
four low
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Post #15 makes a good reason why Mopar Extended Warranty is a good idea. These are complex vehicles, and failures get expensive FAST
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roaniecowpony
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roaniecowpony
Well-Known Member
But a careful examination of the alternator sprag pulley should reveal whether the grease is coming out of it or just being contaminated with it. Also, engine motor oil smells very specific and has a different smell than greases. Especially used engine oil.
Spank
Well-Known Member
I've got the top of my engine in pieces for this exact same reason. I don't think it has anything to do with the alternator, but it's something with the oil filter housing. Since I can't get an aftermarket one made of metal anytime soon, I'm forced to replace it with another plastic Mopar unit. I originally thought I had a valve cover leak because oil was caked on it, but the gaskets were actually okay.
Apparently this is such a common issue with FCA engines, dealerships sell these things quite often and mine had plenty of them in stock. While I've got this thing totally opened up, I replaced the spark plugs and gaskets anyway.
Despite this being a cheaply designed part, I probably overtorqued the cap during an oil change at some point and tweaked something. I'm in the process of putting everything back together and crossing my fingers the leak is gone. Other than the oil in the valley, I don't see anything wrong with the engine and minus this issue, she's been solid since day one. Luckily, I didn't have any symptoms such as a CEL, misfires, or low oil pressure beforehand.
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Spank
Well-Known Member
I stand corrected. It's not just the oil filter housing, but both. I got the engine put back together, everything is sealed nice and tight, and I'm still getting that line right under the belt. I've got an alternator on order that I'll replace on Monday.
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Spank
Well-Known Member
It wasn't really that bad up until recently. I probably made it worse with the last oil change I did about a month ago, but based on how much I had to clean off, I'd guess it's been a very tiny problem that's been growing since the summer. I can't really measure how much oil it's been losing, but it was enough that fixing it has eliminated a rough idle. I was probably short a quart. I didn't take any pictures, unfortunately, but the entire passenger side valve cover was caked real good. The driver side wasn't quite as bad.
The grease spray from the alternator is a very recent development and looks just like the OP's picture. Since I had oil everywhere and definite signs of a leak, I just assumed the line under the pulley was another part of it.
mwilk012
Well-Known Member
I sincerely doubt that the oil leak had anything to do with a rough idle. More likely the resealing of the intake and fresh spark plugs.
j.stotts
Well-Known Member
Since there was no update for this I’ll leave this here for any future people that have this issue. I had the same issue as the OP and it was that bearing leaking on the alternator. Replaced the alternator and now there is no issue. Mine was the bigger tow package alternator FYI.
Kajmcbride
Well-Known Member
I have the tow package with the upgraded alternator and I don't want to replace the entire alternator just because the pulley is leaking grease. I would rather replace just the pulley before it fails, saving around $300.
I looked all over the net and was unable to find an Alternator Decoupler Pulley to fit a JL. FYI the Napa part link Roniecowpony posted earlier in the thread does not fit the JL according to Napa. However all the other infromation Roniecowpony posted was very helpful. If anyone has had any luck finding just the Alternator Decoupler Pulley for a JL please let me know. Thanks in advance
I looked all over the net and was unable to find an Alternator Decoupler Pulley to fit a JL. FYI the Napa part link Roniecowpony posted earlier in the thread does not fit the JL according to Napa. However all the other infromation Roniecowpony posted was very helpful. If anyone has had any luck finding just the Alternator Decoupler Pulley for a JL please let me know. Thanks in advance
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