how do I check intake manifold gaskets for leaks?
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Cruiser
Joined: Dec 2010
Posts: 121
Likes: 0
From: Fredericksburg VA
how do I check intake manifold gaskets for leaks?
Just finished putting my engine back together and it is running VERY rough. I suspect there might be an intake gasket leaking, but I'm not sure how to check it. I remember somewhere reading that if you spray something on the intake gaskets while the engine is running and the engine smooths out it is a leaky gasket, BUT I don't recall what the "Something" you spray is. Help Thanks
Outstanding HDF Member
Joined: Nov 2007
Posts: 2,289
Likes: 22
From: Beautiful Downtown Burbank
Propane at low pressure is the recommended way. Regulate it down to a couple of psi and use a 1/8" hose to direct it around. Listen for an increase in rpm's.
I use ether, its more fun, as long as you dont use a lot. Listen for the knock when the smallest amount enters the air stream.
I dont like using WD40 for a number of reasons, and I'll leave it at that.
I use ether, its more fun, as long as you dont use a lot. Listen for the knock when the smallest amount enters the air stream.
I dont like using WD40 for a number of reasons, and I'll leave it at that.
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Banned
Joined: May 2005
Posts: 12,594
Likes: 9
From: Bama
Yes to propane. I use it every time I change a set of pipes and it can find leaks that you didn't even know that you had.
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Stellar HDF Member
Joined: Feb 2010
Posts: 3,396
Likes: 266
From: Southern California
Actually, water in an old windex spay bottle works pretty well. The water will temporarily seal the leak and then it will quickly evaporate. It doesn't leave a mess, because the water evaporates fairly quickly. It is easily repeatable, and it's very specific about the location to which it is applied. In the hands of a DIYer propane can be a bit confusing. If it gets into the engine in the normal way, via the Throttle Blade, you'll get a response from the engine, but there really isn't any vacuum leak. Granted using water doesn't get as dramatic a response from the engine as using propane, but it is also a bit less adventurous.
Road Master
Joined: Apr 2009
Posts: 1,123
Likes: 43
From: NJ
Carb cleaner turns the engine black paint, white. Propane is the way to go and you don't need to be exact in the location of the leak, if you find any leak in the manifold you are going to change all the gaskets anyways and the voes line as well.
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