OMC Exhaust flapper valves

[johnbo]

Hi,

Pulled the outdrive on my buddies boat this evening (5.0L OMC Cobra) and noted that it appears that one of the flapper values is stuck in the bottom area of the Y pipe. The question is should I pull the other flapper or replace this one?

I know about the Volvo Service Bulletin on the removal of the flapper valves. I've read here somewhere that Merc is still recommending them.

What is the consensus on the OMC setup? Yank 'em or replace 'em?

Thanks,

johnbo

 

[Boatin Bob]

Re: OMC Exhaust flapper valves

As far as know you should still have them on an OMC, if you decide not to and your buddy sucks some water into his engine you might have expalining to do.

 

[lrlima]

Re: OMC Exhaust flapper valves

I just swapped my 4.3 motor last week. In the process, I replaced both flapper valves. The originals (1993) were both in fair shape, but one didnt move to freely due to exhaust build up. Forpeace of mind, I replaced them.

Funny, I live in Cornelius, North Carolina....

 

[lakelivin]

Re: OMC Exhaust flapper valves

I found the same thing with my '89 4.3L and just replaced both flappers.

Here's a tip that might make the job easier for you. Buy some Astroglide from the 'personal products' area of a drug store or wal-mart. Use a blunt instrument to pry the rubber connectors away from the metal risers enough to squeeze a little of the lubricant at various points around the risers. Twist to distribute it all the way around the riser once you've got it applied to both ends of the piece you want to remove.

After removing the pieces you need to access the flappers, clean everything thoroughly and apply more Astroglide to the inside of the rubber connectors before hooking everything back up.

Astroglide is super slippery so it makes removal & re-installation alot easier, and it's water based so it shouldn't hurt the rubber connectors at all. Made the job ALOT easier for me.

 

[johnbo]

Re: OMC Exhaust flapper valves

The funny thing is that I've never had a problem getting the rubber bits off of the exhaust pipes (I've only done two boats). Just a little bit of wiggling seems to pop the seal between the rubber sleeve and the metal part. They (so far) go back together pretty easily dry. But, it might be the age of the boats too ('96 and '92)

Thanks,

johnbo