No drain plug on OMC Cobra Exhaust Elbow

Stan's Customs

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This '88 Cobra 5.7 does not have drain plugs like Mercruiser on the Exhaust Elbow above the Exhaust manifold. Does it drain when the Exhaust Manifold plugs are pulled or do you remove the Elbow , or...???<br /><br />Thanks...Stan
 

Bondo

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Re: No drain plug on OMC Cobra Exhaust Elbow

Hi Stan,<br />As I've stated before,<br />I Don't Do OMCs.........<br /><br />But,<br />I think you'll find that the Center-Riser/Elbow type of manifolds have a self-draining riser/elbow.......<br />In other words, Ya, they drain Through the manifold.....<br /><br />Merc. hasn't had drains on the riser/elbow since the old Log style manifolds........
 

Stan's Customs

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Re: No drain plug on OMC Cobra Exhaust Elbow

Thanks Bondo..<br /><br />Actually the Elbow is at the rear of the Exhaust Manifold on the top. I have to assume it drains when the manifold is drained since ut has no drain cocks...like the center rise manifolds you mentioned. I was just making sure they didn't have to be removed or something.<br /><br />How long ago did they last make the old log style manifolds..seems like yesterday that I pulled plugs out of the risers too..<br /><br />Thanks for the help ...Stan
 

KaGee

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Re: No drain plug on OMC Cobra Exhaust Elbow

Yes, they drain through the manifold. Mine do not have any either. Gravity takes care of everything.
 

Bondo

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Re: No drain plug on OMC Cobra Exhaust Elbow

How long ago did they last make the old log style manifolds..seems like yesterday that I pulled plugs out of the risers too..
It's been a Quite Awhile.................<br />'Course, We were working on Older Boats back then Too................ ;)
 

Scaaty

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May 31, 2004
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Re: No drain plug on OMC Cobra Exhaust Elbow

I have aftermarket Barr one piece and can't even get to one back bottom drain. So I don't do either, just pull the front hoses and fill with antifreeze.......
 

Lou C

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Re: No drain plug on OMC Cobra Exhaust Elbow

The OMC log style with the rear riser did not use a seperate drain, they switched to the center riser style in 1991.<br />My 88 V-6 has the oddball one piece manifold/riser, only OMC made them, no aftermarket was ever available for that style, so when it comes time to replace them I will probably have to convert to the center riser style.
 

rybad

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May 20, 2004
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Re: No drain plug on OMC Cobra Exhaust Elbow

I have 1988 5.7 Cobras. My port side has a drain plug on the risers, the starboard side does not. However, the exhause manifold have a rubber capped draing plun underneath, towards the aft. They are kept on with stainless steel screw straps. Remove the rubber caps, and let them drain. You may want to run a coat hanger or something up the hole to break away any corrosion that is blocking the hole. (do the same on your engine block too!!)<br /><br />-David
 
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