valve cover Valve Covers: Any Good Aluminum Aftermarket Solutions?

[NickyV]

Hello All,

 

I've been researching valve cover replacements. I've still got a lot of research to do, but I'm wondering if anyone has had any good experiences with aftermarket VCs? I have a 1987 2.5L. Some of the posts about this topic are over 10 years old. In those, people tend to talk about finding a VC at the JY. But doing some searching on the old Googles, I'm seeing that Crown Automotive claims to offer an aluminum aftermarket solution.

 

I really know nothing about this, but I'm a little worried it's too good to be true, especially because it costs less than $50 on Amazon: https://www.amazon.com/Crown-Automotive-33003857-Valve-Cover/dp/B008VPWLRG

 

Any chance this might work? If not, what should I look for?

 

Mine is currently leaking. Not badly, but I want to eventually fix it.

 

Anything else I should be worried about? Like... if I've been driving it with a leaking VC for years and I suddenly seal that up tight, could it lead to other issues? I'd really hate to blow my head gasket. Then again, there's a high likelihood that my HG has never been replaced. Maybe it's only a matter of time.

[eaglescout526]

So with the 2.5L and what I learned over the years is the plastic remake from crown is an absolute pile of dog crap. Do not buy it and stay as far away from them as possible. 
now that my rant is out of the way. Stick with OEM on the valve cover. AMC and Chrysler used a harder thicker plastic that crown doesn’t seem to know. Either they’re too cheap to make true restoration parts or have never worked on an XJ or MJ. 
I still run the original hard plastic valve cover and have little to no issues with leaks what so ever. As long as you have the right gasket and some RTV. Now the hard plastic covers are supposed to have a reusable gasket so you don’t have to use RTV with the separate gasket that you get but I’d expect that gasket to be old and failing   
 

Now to aluminum covers. 
Id use one but they don’t have the AMC logo and appeal entirely to the aesthetic I want. Now you do have to do some vacuum rerouting to use the aluminum cover. Oh and you have to get the bolts for the cover too. Can’t reuse the old shoulder bolts from the plastic cover. 

11 minutes ago, NickyV said:

Anything else I should be worried about? Like... if I've been driving it with a leaking VC for years and I suddenly seal that up tight, could it lead to other issues? I'd really hate to blow my head gasket.

No. You don’t have to be worried here at all. The valve cover is meant to prevent the oil from leaking out of the top from the rockers. The vapors from oil then get sucked up by the throttle body and thrown into the combustion chamber. Be next to near impossible to blow your head gasket from a sealed valve cover. 

[NickyV]

Thanks, @eaglescout526. So, if I understand you correctly, you're recommending that I start by just replacing just the gasket on the VC I have? Honestly, I'm fine with keeping the plastic gasket. I just want it to work and to stop leaking oil!

[eaglescout526]

I would start there unless you have a lead on an aluminum cover and everything else for the swap. 
 

What I did was get a genuine valve cover gasket, don’t think Chrysler has them anymore, put some RTV on the cover and put the gasket with the RTV to make alignment easier and then mount the cover. Now the cover does have torque specs so you don’t crack or warp it. It’s about 11 ft pounds. 

[NickyV]

Thank you again. I have the Haynes Manual and I think that it might use some different terminology than I've been using. It calls the valve cover the "rocker arm cover." I do not doubt your experience, I'm just trying to get on the same "page" as it were.

 

It says "rocker arm cover-to-cylinder head bolts "55 in-lbs" with RTV. That's a lot more than you've recommended. Why do you think that is? Or am I looking at the wrong part? I don't see "valve cover" in the index of this manual.

[eaglescout526]

I mean it’s not wrong. It covers both the rockers and valves. 
 

Actually that 55in pounds might be more correct. I’ll need to double check with my 2.5L book. I can only speculate I got 11 as the numbers being the same. 
 

Im surprised a manual like that would recommend RTV all the way vs getting the gasket and some RTV unless the text is based on the assumption you have the gasket and to put some RTV on the cover. 

[NickyV]

Here's the fine print: "On models with plastic rocker arm covers, RTV or a gasket may be used. On models equipped with an aluminum rocker arm cover, RTV must be used. Later models use a pre-cured reusable gasket - install these without sealant." (Italics added by me).

 

The page with the torque specs lists torque being 55-in-lbs for RTV and 44-in-lbs for the model with the built-in gasket.

 

 

[eaglescout526]

I’ve never trusted Haynes or chiltons manuals for anything other than basics and when official material isn’t available. 
But I would still run both gasket and RTV on the plastic as I’ve had gaskets get a little squished even though there torqued to spec and for the aluminum guys, probably just the gasket will do just fine as they don’t run a huge risk for warp. 
 

I’ll get the details this evening from my 2.5L book. 

[NickyV]

Thank you! I appreciate that!

[eaglescout526]

Ok so yes the 55 in pounds is correct torque. 

 

Now if you reallllllly want to get to the nitty gritty. Theres an 84-86 procedure and theres an 87-88 procedure. And I love the 87-88 as it says this

"1987-1988

Install the cover on the cylinder head

Tighten the mounting bolts to 6.2 Nm (55 in-lbs) torque."

[GonzoTheGreat]

I bought a crown one. It was narrower in the middle than at the ends, so the bolt holes only lined up when I flexed the plastic. It had a kind of reusable seal cast into it, but I also used RTV. It stayed dry for about a week before it started leaking. I wouldn’t recommend it to anyone who wants a clean engine bay. It weeps very slowly, with no noticeable oil loss, so I’ve chosen to just live with the free rust prevention. 
 

The plastic on the original valve cover was much higher quality, but it had unfortunately been broken by a PO. You should be able to just reseal your original VC and call it a day. 

[NickyV]

Thanks for the additional input, @GonzoTheGreat. Sounds like I’m just gonna get a new seal. And go from there.

 

Haha, @eaglescout526! I had to Google what NM stands for. So scientific!

 

By the way… I just want to say that I love this forum! Every time I dip into one of the many XJ or YJ forums to research something, I see a bunch of one-sentence answers and rude responses to honest questions like “Let me Google that for you.”

 

Y’all really care out here!

[89 MJ]

27 minutes ago, NickyV said:

By the way… I just want to say that I love this forum! Every time I dip into one of the many XJ or YJ forums to research something, I see a bunch of one-sentence answers and rude responses to honest questions like “Let me Google that for you.”

 

Y’all really care out here!

This forum is really one of a kind. I’m hoping you stick around. You seem to do very thorough research before asking a question and the headlight relay harness was very well done. 

[NickyV]

Thanks @89 MJ. I plan to stick around and do more write ups! I enjoy it!