does this exhaust riser need replacing?

[trucknutz36582]

This is on a 2003 Stingray MS200 with the 4.3 mPI . About thousand hours on the motor..
Second owner, the seller - told me manifolds and risers were supposedly changed out 3 or 4 years ago by the original owner -

It ran fine the last two outings when I was figuring out where the noise was coming from (bad gimbal bearing)
but now that I have a outdrive installed, it won't run smoothly over 3,000 rpm.
Local mechanic advised me that exhaust manifold or riser may be leaking water into the engine...

what do I do next? acid dip? or take to an egine shop to have it dipped & cleaned like an engine block?

or just go get a new one?

thanks in advance

 

[Bt Doctur]

boats 13 years old, giving 5 year life on average your on the third set or a very tired second set .You always want the graphite gaskets not paper ones

"take to an engine shop to have it dipped & cleaned like a used condom?"

 

[NHGuy]

No sense try to keep that. Too plugged and rusted.
There's a pair for sale in NH. On Craigslist

 

[Bondo]

Ayuh,.... Welcome Aboard,.... Ya can't inspect the riser til ya clean the gasket surfaces so's ya can see 'em,.....

A flat file works good,....

Yer lookin' for gasket surfaces 'bout 1/4" wide or wider,.....

 

[trucknutz36582]

thanks I'll clean them up this weekend. are all the gaskets the same pattern for Osco risers? should I be looking for a pair of the same brand , or are they interchangeable ?

IS this the correct Mercury part number? [h=1]27-863724 or do I need Osco 8503-GR or ???[/h]
[h=2][/h]

 

[trucknutz36582]

ok here's what the riser looks like cleaned up. other side more or less the same.

Do you guys think it will make it for the 60 hours
or so I need to make it through the rest of the season? I don't need it to last years, just a few more months.


plan is to pull the motor and replace with new gm long block around the first of november, when our boating season ends.

reuse what I can - replace what i should.
I really would prefer the dry joint exhaust to add to the new motor - is there any issue I need to be aware of?

 

[achris]

That elbow looks ok. Use the graphite Merc gaskets. Any others promote leaks.

Dry-joint. Great system, but the tubulator gaskets are very exxy... Like $45 each. There are 2 different down-angles of the dry-joint elbow. To change from one to the other also means a change of the aluminium tube immediately below the elbow (also called an 'elbow').... Just the look of the elbow in one of your pictures it looks like a 7 degree. There are 7 degree dry-joint elbows. All the manifolds are the same regardless of the elbow down-angle.

7 degree down-angle dry-joint elbow part# -864309T02
Dry-joint manifold part# -864612T01
Elbow gasket part# 27-864850A02
Manifold gasket part# 27-99757

Chris......

 

[trucknutz36582]

Thanks Chris! I