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Thread: Intake Manifold gaskets

  1. #1
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    Intake Manifold gaskets

    Hi everyone,

    So while doing my CAM timing, obviously, I have full access to the intake manifold gaskets. They look to be in decent condition still (last time I looked at them was about 1 1/2 years ago and only 3K miles added since).

    However, I was looking to see if these are salvageable at all. Most folks on here seem to throw theirs away and replace with new ones as they come out so hard and or brittle. Mine seems to be okay still and I have had no vacuum leak that I'm aware of.

    I was searching to see if there's a way to refresh/restore the softness/flexibility back into the rubber and possibly reuse them if they have not went beyond the saving stage. What I found was this idea:

    #################################################
    Rubber Softener

    A traditional problem of restoration has been the deterioration of rubber intake moldings. There is a way to reclaim neoprene rubber components that have hardened with age. The problem is that the synthetic rubber contains plasticiser chemicals, which keep it supple, and these tend to bleed out over the years.

    The answer is to soak the rubber in a chemical that will replace the original plasticisers and restore it to its original pliable state. The chemical is available at any camping shop….the silicone waterproofing that is sold for re-proofing tents.

    The technique is simple: Soak the rubber all over with the silicone spray, pop it into an air tight bag and let it soak for a few days. You will find that the proofer slowly soaks into the rubber and restores its original suppleness. On badly hardened rubber you may need to repeat the treatment.


    Credit: http://www.kawtriple.com/mraxl/tips/rubbersoftener.htm



    ##################################################

    So if this is true, it's worth the shot...possibly save about $500. I'm going to give it a try and report back. I'm in no hurry to button up the valve covers just yet so I have a week or so to try this out. Will take pictures and report my finding.

    Cheers,

    Chris

  2. #2
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    If you want to be 100% sure they will not leak, then apply a thin (1mm) bead around the openings and install. Install the nuts finger tight, wait 15-20 minutes, then torque to 7.5 lb/ft.
    Repeat this process when attaching the intake manifolds. The intake manifold gaskets will now last you another 20 years.
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  3. #3
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    Cool. Thanks for the advice, Steffen. I bought some expensive gasket sealant particularly for this reason. I don't recall the brand off the top of my head but some senior members on here recommended that only.

    Cheers,

    Chris

  4. #4
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    You should be using REINZOSIL, and nothing else.
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  5. #5
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    Real men use Hondabond 8^)
    How come the middle half of any project always takes the most time?

  6. #6
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    Quote Originally Posted by Max Lumens View Post
    Real men use Hondabond 8^)
    No Japanese stuff on my Munich-machine!
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  7. #7
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    Quote Originally Posted by TxGR8White View Post
    You should be using REINZOSIL, and nothing else.
    Yes, that's it. I was just too lazy to run to the garage...

  8. #8
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    "silicone waterproofing that is sold for re-proofing tents" - do you have any brand name and does it really work?

  9. #9
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    Sorry, Olajan. I haven't tried it yet and what I posted was only information I found online from researching. I suppose you could get something similar from an outdoor sporting goods establishment...if one is available in your area.

    Cheers,

    Chris

  10. #10
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    Quote Originally Posted by TxGR8White
    You should be using REINZOSIL, and nothing else.
    I used this stuff last weekend on my lower oil pan gasket on both sides. Also, I spread a thin coat of the sealant evenly across the mounting surfaces. No leaks whatsoever.
    1991 BMW 850i / ZF4HP24 E/H

  11. #11
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    I was under the impression intake gaskets are always installed dry...I have never heard of lubing them.

  12. #12
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    Quote Originally Posted by mjrgroup View Post
    I used this stuff last weekend on my lower oil pan gasket on both sides. Also, I spread a thin coat of the sealant evenly across the mounting surfaces. No leaks whatsoever.
    It is actually better if you run a continuous 1mm diameter bead on the sealing surface and let the 2 joing parts "spread" the sealant out. This ensures a consistant coverage and seal.
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  13. #13
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    Very good advice on the use of sealants, but does anyone have experience of re-conditioning the rubber in the intake gaskets by soaking them in some kind of silicone product as suggested? Does it work or is it a waste of effort?

  14. #14
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    I have successfully used HYLOMAR various times. Pretty common stuff on this side of the pond.

  15. #15
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    Quote Originally Posted by olajon View Post
    Very good advice on the use of sealants, but does anyone have experience of re-conditioning the rubber in the intake gaskets by soaking them in some kind of silicone product as suggested? Does it work or is it a waste of effort?
    Hi Olajon,

    I had the manifold intake gaskets cleaned as much as I could yesterday and sprayed them down with water, patted dry with paper towels, sprayed generously with Pyroil silicone lubricant, and placed in clear plastic bags air tight. This was done yesterday evening so it's not quite 24 hours yet. I will check on them later in the day and see if that has done anything. Will report back.

    Cheers,

    Chris

    EDIT: Attached are a couple pictures of the intake manifold gaskets soaked in the silicone lubricant spray and placed in air tight clear plastic bags.
    I took them out to visually inspect...not sure if the lubricant soften them up as they are still pretty hard. There are no visible cracks to start with. I was able to pinch and make indented marks with my nails so perhaps this process might just work, provided the gaskets are not completely dried out and brittle. I plan to leave them soaked and apply another coat or two for another day or so. Prior to installation, I will let them air out for a couple days in the shade to make sure the surface dries up nicely.
    Attached Images Attached Images
    Last edited by ChrisFuture8; 03-14-2012 at 05:16 PM.

  16. #16
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    Thank you Chris, I'm looking forward to your next post on this!

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    There is a turtle wax (I think that was the brand) product that claims to soften and revitalize rubber trim pieces, I wonder if that is just the same thing?

  18. #18
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    Quote Originally Posted by Cadillacwill View Post
    There is a turtle wax (I think that was the brand) product that claims to soften and revitalize rubber trim pieces, I wonder if that is just the same thing?
    Not sure, Cadillacwill. I looked online on various types of silicone spray and tent-reproof stuff. They all seem to have some type of silicone as the main ingredient. Since I have the Pyroil can in my stash, I decided to give it a try. Others have said brake fluids will certainly do the job but it will also cause swelling of the rubber. I don't want to gaskets to swell, I just want them to become more pliable so they seal better. We'll see.

    Cheers,

    Chris

    Quote Originally Posted by olajon View Post
    Thank you Chris, I'm looking forward to your next post on this!
    ...certainly, Olajon. Will update you for sure.

    Cheers,

    Chris
    Last edited by ChrisFuture8; 03-14-2012 at 05:52 PM. Reason: Automerged Doublepost

  19. #19
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    Any news on this Chris?

  20. #20
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    Hi Olajon,

    Unfortunately, I still have not been able to get my car to run on both banks. Still having trouble with the driver's bank.

    I have not seen a brand new set of intake manifold gaskets so I don't know how soft they are when new to compare with. The stuff I did on the intake doesn't seem to soften it up as I thought. They still feel pretty hard. You can't flex it with your hands, but I'm not sure if the new ones are like that as well. Otherwise, they look nice and shiny after I applied the silicone lubricant and let them sit for a few days. I wiped them dry prior to installing them.

    They seem to seal well for now but because I haven't been able to drive the car, I can't really tell. It's worth a shot if yours are not brittle or in bad shape (such as noticeably leaking air through). Sorry for not having an scientific based tests done (too busy trying to troubleshoot the unexpected problem).

    Cheers,

    Chris

  21. #21
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    The real "key" to all of this is the small raised ring surrounding each opening. Over time this part of the gasket becomes flattened, and once that happens, the sealing ability of the gasket is compromised - you can only tighten them so much. Although having a "soft" gasket helps, they do develop small cracks or fissures over time and no "magic silicone" treatment will undo theose cracks - it is only a short term solution. Been there done that, it didn't work as promised.
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  22. #22
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    so how are the intake manifold gaskets soaked in the silicone lubricant spray and placed in air tight clear plastic bags working after 5 years?
    Works or not?
    Is Max Luemens still selling his silicone intake gaskets? http://bmw8.us/Silicone%20IM%20Gaskets.JPG what is the present price?

    So far I used liquid seal like Hylomar or some similar stuff from Toyota and it works.
    Genuine Toyota Fluid 00295-00103 Formed-in-Place Oil Pan Gasket
    Sets to form an elastic body which is not affected by vibration or impact
    • Maintains a stable rubber body over an operating temperature range of -76°F to 482°F
    • Highly resistant to engine oil, various chemicals and coolant
    • Use on the water pump, oil pan, valve cover, engine head, fuel pump, thermostat housing, oil pump and intake manifold
    • Five-minute tack free time
    Last edited by shogun; 02-10-2017 at 09:32 PM.
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  23. #23
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    Well, long story short, I ended up putting out the cash and purchased a brand new set because I got tired of troubleshooting vacuum leak and LHM. Compounded problems over a number of months caused me to cave in. I think if the IM gaskets are not cracked and left soaked in for a few days, they can be safely reused. My vacuum leak turned out to be the fuel injector O-rings.

  24. #24
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    Quote Originally Posted by ChrisFuture8 View Post
    Well, long story short, I ended up putting out the cash and purchased a brand new set because I got tired of troubleshooting vacuum leak and LHM. Compounded problems over a number of months caused me to cave in. I think if the IM gaskets are not cracked and left soaked in for a few days, they can be safely reused. My vacuum leak turned out to be the fuel injector O-rings.

    Those are the only seals I haven't replaced last two weeks ago when I was doing my intake.

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    As far as I.M.G. are concerned I highly recommend going the RENZOSIL route and re using your old gaskets. Take them off, clean them well as well as mating surfaces. Apply black RENZOSIL to head and runner surfaces and install the gaskets. Never had a leak on any of them. That stuff is amazing!

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