Here's how to replace your valve cover gasket

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snelson
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Here's how to replace your valve cover gasket

Post by snelson »

Here's how to replace your valve cover gasket

I know this is a pretty easy project for most, but just thought I'd post steps/details on how to change the valve cover gasket in case anyone else wants to tackle this themselves.

Set aside maybe an hour or two, and all you need is:
- 10 mm socket / wrench
- 12mm socket / wrench
- a torque wrench in inch pounds (not 100% necessary but always good to use/have)

Valve cover gasket kit/set which should include:
- valve cover gasket
- small half moon rubber piece
- 2 small rubber bushing/washer type pieces.

Some Form In Place Gasket goop - (not 100% necessary but comes in handy when placing the small half moon)

Image

Steps:

First remove the fan shroud - there's a small obvious clip on top of the fan shroud. Remove this.
Next slide the piece of shroud closest to the passenger door towards yourself to get it to 'unlock'. Push it down into the engine bay in order to get it under and around the upper rad hose and remove this piece of shroud. Next, there's a tiny screw to remove on top of the other half of the fan shroud, remove this screw, and slide the last piece of fan shroud out.

Now remove the timing belt cover. There are 5, maybe 6 bolts to remove. There are 2 longer bolts, and maybe four smaller bolts. The two longer bolts are actually different lengths, so when removing them, just remember which one came from what hole...

Image

Now you can start to remove the valve cover. There are only 2 bolts holding the cover on. There is also a smaller single bolt near the back of the cover holding the metal vacuum hose assembly to the cover. Remove these bolts but also take note of the order that the additional pieces on the front bolt are assembled so when you reassemble later, you know what piece goes where.

Image

The next step is to remove the small rubber vacuum hoses as well as a larger hose on the far side of the valve cover. Be careful and take your time removing these hoses as some may be brittle/hard and you don't want to tear them. You don't really need to remove all the hoses, just enough so that the metal vacuum tubes can be moved to one side. This will allow for easy removal and installation of the actual valve cover. I removed all the hoses on the front end of the metal vacuum hose assembly. There's also a hose leading from the injection pump - mine was braided - carefully remove this hose too and move it to the side.

**Remember when removing hoses it's a really good idea to use some tape to label each hose as well as where it was connected. So when you go to reassemble, you're not second guessing yourself as to what hose goes where...

Ok, so the bolts and hoses are removed, so now just give the valve cover a whack with a rubber mallot if needed or just a pop with your fist should allow you to remove the cover. Once the cover is removed, reach back and remove the small rubber half moon. Feel around at the back of the head, and you can pry it out/off with your hands.

Image

Replace the old valve cover gasket with the new and place a small film of fresh oil along the new gasket with your finger. Replace the 2 rubber stoppers/washers onto the long valve cover bolts. Double check the top of the head that it's clean and there are not pieces for dried up gasket stuck to it. If there are any, remove them with a plastic scraper and clean/dry this same surface.

Image

When replacing the half moon, this is where I used some 'Form In Place Gasket' goop. Place a small beed along the curved part of the moon (this is the bottom). This will allow act like a glue to make sure the moon doesn't move once you've place it back on the head and are putting the cover back on top.

Image

With the new gasket in place in the cover, and the half moon in it's place, put the cover back on top of the head, and replace the long bolts to tighten down the cover. At this point I just finger tightened the cover bolts, then connected all the vaccum hoses and made sure everything was seated properly. Now tighten the large cover bolts to 4-5 foot pounds of torque.

Image

Replace the timing belt cover **Make sure you didn't drip any oil on the belt, if so, make sure you wipe it off well. Tighten the timing belt cover bolts (didn't have a torque for this, but just make sure they're hand tight.) Also, make sure the timing belt cover is seated properly so no outside moisture/grit can make it's way in.

Replace the fan shroud and make sure all the shroud teeth connect - I noticed just as I was about to shut the 'hood' that the last shroud piece wasn't actualy seated properly.

That's it - start her up, let it run for a while and make sure everything is sealed properly and that you have no leaks - especially at the rear half moon area....

:M 8-)
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Re: Here's how to replace your valve cover gasket

Post by delicat »

Good post, well detailed!

And it's always good to hear (and see) that it's as easy as it sounds! Anyway, we can't have enough servicing tutorial on this type of forum so thanks again!
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Re: Here's how to replace your valve cover gasket

Post by wetcoast »

Would look sweet powdercoated RED!!
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Re: Here's how to replace your valve cover gasket

Post by MrDuncon »

Great Post!

My serviceman will do this next saturday :-D
... and i think torque wrench is necessary.

Good job anyway
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Re: Here's how to replace your valve cover gasket

Post by after oil »

just did this, took less than two hours! thanks for the tutorial!
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Re: Here's how to replace your valve cover gasket

Post by Slimdog »

Great write up it helped me out.

One question though when I put the half moon gasket in place it felt like it was sticking up above the head surface by about 1/32". I assume thats why we use the sealant there? or did I not seat the gasket right?

Cheers

S
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Re: Here's how to replace your valve cover gasket

Post by RichD »

wetcoast wrote:Would look sweet powdercoated RED!!
Autosol FTW.
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Here's how to replace your valve cover gasket

Post by leedavis »

Thanks for this post. Very nice guide on replacing the valve cover gasket set.. By the way, I used autosol and it worked wonders.
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Re: Here's how to replace your valve cover gasket

Post by White Mule »

Nice post!

Is there a part number available for the replacement kit?
Thanks,

White Mule
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Re: Here's how to replace your valve cover gasket

Post by White Mule »

1987 Ford Ranger 2.3l Diesel has the same gasket.(4d55)

Part number: 91717 (valve gasket)
96264 (half moon)

Part Source $23.00
Thanks,

White Mule
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Re: Here's how to replace your valve cover gasket

Post by Morganizer »

So, how many half moon seals are there, one or two?

I ordered a gasket from Maximum Overdrive*, and the mechanic said there are in fact two half moon seals, one at the front and one at the back. He said lots of times people just replace the back one, because the front one is harder to replace. It seems the back one is most likely to leak, but if the front one leaks, oil gets all over your timing belt. He said it's tricky, but just possible to slip it in, so worth doing if you can.

* $28 + tax and Canada Post = $40. That's without the half moon seals.
The Web site says "Made in Japan by Fuji" but the part that arrived says, "Made in Korea by Rhee Jin".

I ordered an aluminum half moon from a company in Michigan called Strictly Import Motorsports. I increased the quantity to two after talking to Maximum Overdrive, so I'll either replace both (if it's true and feasible) or have an extra one for a swap meet.
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Re: Here's how to replace your valve cover gasket

Post by FalcoColumbarius »

There should be in the package:
  • one half moon seal,
  • two grommets
  • one rocker cover gasket


The half moon seal goes in the back of the motor. You will find reference to this in the shop manual section in the L300 Technical Reference Library. You will also need a sealant ("3M ATD Part Number: 8660, or the equivalent") to put onto the half moon seal.

Falco.
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Re: Here's how to replace your valve cover gasket

Post by jc1300 »

Well, thanks for that tutorial. I need to change mine as well, as I have a leak at the bottom of the half moon in the back of the engine.
So, if I understand well, there is one gasket for that bottom part, and you use sealant to keep it in place. Does that "Ultra black" RTV gasket maker is made for ?
Then I guess there in another gasket that comes on top of the engine block so as to seal with the valve cover ? Am I right ?

Then another question, I read in that thread that the "1987 Ford Ranger 2.3l Diesel has the same gasket.(4d55)" Is that correct ? Then where is the most interesting place to order that part ? Any Lordco or Napa or should I order online ?

Thank you very much for your help.

JC
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Re: Here's how to replace your valve cover gasket

Post by Tojo »

Hi JC,

The halfmoon is a hard plastic or aluminum part, not a gasket. Put a bead of high heat silicone in the groove and press the halfmoon in there so it creates a good seal. The trick is to apply enough goop to seal the halfmoon, but not too much, or the excess silicone may fall into head and cause issues. Make sure that you press the halfmoon deep enough so that the mating surface for the valve cover gasket is smooth and flush. I would not use silicone between the valve cover and the valve cover gasket as it creates a big mess to clean up later. The hardest part about this job is getting back there under the engine cover, and being able to see what you're doing. I use a small mirror.

The pictures are not from a Delica, but you get the idea.
Good luck!
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Re: Here's how to replace your valve cover gasket

Post by FalcoColumbarius »

Don't forget to sufficiently clean the surface of the head of oil/grease (with a degreaser) that the gasket/seal connects to so the sealant can stick.

Falco.
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