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 #76238  by gheiss
 March 23rd, 2005, 4:50 pm
When changing plugs a few weeks ago, I noticed a slight leak on #5's plug tube. (oily plug base and boot) All other cylinders were dry. I pulled the plug again after a week and it was oily again. Are these plug tube seal hard to change? They are a cinch in a Honda, but looks like the M could be a bit of a challenge.

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 #76959  by D76G12
 April 3rd, 2005, 8:47 am
Just looking at the '02 FSM - it looks like you have to remove the valve cover ...

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 #146185  by Arved
 September 15th, 2007, 10:49 am
D76G12 wrote:Just looking at the '02 FSM - it looks like you have to remove the valve cover ...
Would a loose spark plug tube cause an oil leak around the spark plug?

I just changed my spark plugs, and noticed oil around the (external) base of the #4 and #5 spark plugs. I haven't disassembled anything yet. The oil really concerns me. I dispise oil leaks. Reminds me of Harleys...

:itchy

 #146186  by Shadowvox6
 September 15th, 2007, 10:52 am
The tube seals can detoriate over the course of time.
Typically, they will come with the valve cover set.
If you have to remove the valve covers anyhoo, good time to replace those gaskets.

I would go Fel-Pro, their gaskets are top notch.

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 #146188  by D76G12
 September 15th, 2007, 11:03 am
shadowvox6 wrote:The tube seals can detoriate over the course of time.
Typically, they will come with the valve cover set.
If you have to remove the valve covers anyhoo, good time to replace those gaskets.

I would go Fel-Pro, their gaskets are top notch.
Spot on as usual! If Fel-Pro makes it I use it ... :D

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 #146190  by Arved
 September 15th, 2007, 12:53 pm
D76G12 wrote:
shadowvox6 wrote:If you have to remove the valve covers anyhoo, good time to replace those gaskets.

I would go Fel-Pro, their gaskets are top notch.
Spot on as usual! If Fel-Pro makes it I use it ... :D
With a recommendation like that, it's tough to argue otherwise. Next order with Rock Auto they'll be included.

I don't have any other reason to remove the valve covers than to replace these seals right now. Anything else I should consider while I'm disassembled that far?

Any other possible source of the leak?

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 #146191  by velobard
 September 15th, 2007, 1:21 pm
Arved wrote: Any other possible source of the leak?
Depends. :lol:

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 #146194  by EasyRider300M
 September 15th, 2007, 3:46 pm
what problem can arise if you put off replacing the seals?

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 #146196  by swalker
 September 15th, 2007, 4:12 pm
Might ruin the coil boot that's about all.

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 #146856  by Arved
 September 28th, 2007, 4:15 pm
shadowvox6 wrote:The tube seals can detoriate over the course of time.
Typically, they will come with the valve cover set.
If you have to remove the valve covers anyhoo, good time to replace .
I got the Felpro valve cover gasket set. Haven't opened the box, but looking at the FSM, it looks like the tubes are set into the head using "Mopar(R) Stud and Bearing Mount." Also seems like the tubes are not reusable. They're destroyed removing them, and you install the new ones using this "Mopar(R) Stud and Bearing Mount."

Do the tubes really need replacing, or does the gasket kit have gaskets/seals that prevent the oil from getting to the head/tube interface to begin with?

Are the tubes a dealer-only item? I can't find them in Rock Auto's parts drill-down.

Thanks,

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 #146857  by swalker
 September 28th, 2007, 4:27 pm
I removed them when I did the valve job on a friends. I used a socket that fit in the tube snug and used vise grips and turned it and removed it. They are a snug fit. I used sealer and drove them back in. The manual says to destroy them so they can sell them to you. Likely leak is the seal at the valve cover end.

 #146862  by Shadowvox6
 September 28th, 2007, 5:23 pm
Chances are, the seal at the top is what is leaking.
I wouldn't take the tubes out at all.
I would take the valve covers off, replace the valve cover gaskets, and the seals in the valve covers.

Not a problem

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 #146867  by Arved
 September 28th, 2007, 10:00 pm
Just a regular gasket sealer? Like this?

Image

Thanks, both of you. I appreciate the quick reply.
 #381700  by G30
 December 25th, 2019, 11:34 pm
I am about to resurface a neighbors 2005 Chrysler 300 3.5l v6 heads. I sold him the car for a hundred bucks because the customer that brought it to me bent a few valves while slinging the timing belt and didn't want to repair it. I have to remove the plug tubes to deck the top of the head right. Thank you for your suggestion about using a socket. I was fearing a tube bending. On the friends car you reinstalled the tubes in... Did it leak ever? What sealant did you use?