intake leak

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motosapien
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intake leak

#1 Post by motosapien » Sat May 13, 2017 6:54 pm

Chasing this leak...any inputs will be helpful

testing at 5psi

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RZed
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Re: intake leak

#2 Post by RZed » Sat May 13, 2017 7:49 pm

You might need new intake manifolds. I bought a pair of urethane ones to replace the original factory ones that were cracking, only to find out they were leaking around the bolt hole after a short period of time like yours. :smt017 I went back to the original Yamaha ones and haven't had any trouble since. :smt023
That's my 2 cents. :smt003

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motosapien
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Re: intake leak

#3 Post by motosapien » Sat May 13, 2017 8:12 pm

New Yamaha flanges..... Fixed the leak after replacing the gaskets couple of times

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kpke
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Re: intake leak

#4 Post by kpke » Sun May 14, 2017 11:23 am

PIA for me that area. I suspect there is many an RZ engine around that was not leak checked that have that leak.

Glad you got it sorted. :smt023

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motosapien
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Re: intake leak

#5 Post by motosapien » Sun May 14, 2017 11:28 am

kpke wrote:PIA for me that area. I suspect there is many an RZ engine around that was not leak checked that have that leak.

Glad you got it sorted. :smt023
i know....first place i looked into was your thread over here. i was reluctant to use sealant, so i took more time trying more gaskets. but dealt with it finally
:smt023
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Hooligan
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Re: intake leak

#6 Post by Hooligan » Sun May 14, 2017 1:48 pm

I have taken to using a spray on sealant on both sides of the paper gaskets. This ensures no possibility of an air leak.
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Smoker
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Re: intake leak

#7 Post by Smoker » Sun May 14, 2017 2:49 pm

motosapien wrote:New Yamaha flanges..... Fixed the leak after replacing the gaskets couple of times
Did you get it sealed with only a dry gasket?

Why reluctant to use sealant?

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motosapien
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Re: intake leak

#8 Post by motosapien » Sun May 14, 2017 2:53 pm

Smoker wrote:
motosapien wrote:New Yamaha flanges..... Fixed the leak after replacing the gaskets couple of times
Did you get it sealed with only a dry gasket?

Why reluctant to use sealant?
I put it in dry and it doesn't leak anymore. It came without sealant from factory I believe. So trying to make it work dry

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motosapien
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Re: intake leak

#9 Post by motosapien » Sun May 14, 2017 2:54 pm

But I'm always open for suggestions

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MK
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Re: intake leak

#10 Post by MK » Sun May 14, 2017 4:19 pm

I always use Dirko (grey) silicone sealant in that area.
No problems ever (if you don't count the jerks that made up the nick Dr Dirko for me)

Keep in mind that Yamaha doesn't always use the best method, but the one that is feasible in mass production and cheap regarding mounting and material costs.
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Smoker
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Re: intake leak

#11 Post by Smoker » Sun May 14, 2017 8:47 pm

motosapien wrote:But I'm always open for suggestions
I use Permatex High Tack (aerosol spray) on both sides. (Sometimes, I only spray one side- like the clutch cover gasket.)

Has worked well for me.

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T.RexRacing
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Re: intake leak

#12 Post by T.RexRacing » Sun May 14, 2017 8:57 pm

Yamabond #4.
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motosapien
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Re: intake leak

#13 Post by motosapien » Mon May 15, 2017 1:06 am

Thanks y'all I will use a thin coat of sealant from now on....
:smt023
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Headcoats
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Re: intake leak

#14 Post by Headcoats » Mon May 15, 2017 4:31 am

The V force reeds come with 2 gaskets , so one fits between the actual reeds and the rubber manifold
Perhaps fit 2 gaskets and a bit of 3 bond maybe ?
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hondaror
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Re: intake leak

#15 Post by hondaror » Thu May 18, 2017 12:39 am

I always oil paper gaskets and have never had problems. I'll let you know when I build my next engine as I plan on doing a leak test.
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