What have I done to my engine?

[Simoniz]

My boat's back in the water and running much more smoothly than before.

Over the winter I've,

Replaced the exhaust, drive and gearshift bellows and the oil and water hoses at the transom

Checked engine alignment but not adjusted it as it was spot on

Replaced Manifold and riser

Replaced exhaust flapper valve (old one was mostly missing)

Now the engine runs smoother and more quietly with less mechanical noise (I swear) and a slightly different exhaust note. Also it idles more smoothly at a lower idle speed (before, to have a decent low idle speed, the motor would gradually run slower until it died).

I cant understand how replacing any of the parts could have that effect but I guess it must be either the exhaust parts or replacing the flapper valve thats done it?

Merc 3,0l

 

[Don S]

Re: What have I done to my engine?

You may have had a vacuum leak with your old manifold. When you put your carb on the new manifold with a new gasket, you probably cured the leak.

 

[crazy charlie]

Re: What have I done to my engine?

[QUOTE



Now the engine runs smoother and more quietly with less mechanical noise

Merc 3,0l[/QUOTE]

Old exhaust flappers will sound very clacky clacky.Running smoother is just how you percieve it to be running because it is quieter.Charlie

 

[TilliamWe]

Re: What have I done to my engine?

...

Replaced exhaust flapper valve (old one was mostly missing)
..l

Don is probably spot on, but if the remaining part of the flapper was restricting exhaust flow, you could have improved that situation.

 

[liquidlew]

Re: What have I done to my engine?

Did you replace the Intake Manifold, or just the exhaust manifold and riser?

 

[Don S]

Re: What have I done to my engine?

Did you replace the Intake Manifold, or just the exhaust manifold and riser?

They (intake and exhaust manifolds) are one and the same on a 3.0L.

 

[Fordiesel69]

Re: What have I done to my engine?

I had water injestion on mine at idle, and it would slug water and idle rough. I will be getting my new manifold soon and will let you know. You replaced it becuase it was leaking water right? I bet you too had minor water injestion.

 

[Simoniz]

Re: What have I done to my engine?

I had water injestion on mine at idle, and it would slug water and idle rough. I will be getting my new manifold soon and will let you know. You replaced it becuase it was leaking water right? I bet you too had minor water injestion.

No, I replaced it because it had spent 7 yearsin saltwater and was loooking badly corroded even on the outside. As far as I know it wasnt leaking but it could have been I suppose.