Chevy Exhaust System

[Lyndy]

My work on my boat will be moving to the engine soon and will be taking detailed pictures of the Non-OMC 5.0 Chevy Engine this weekend. I will be concentrating on the Mercruiser Intake and Exhaust parts. I have read quite a bit about exhaust systems on this board of late and with the reported 750 Hours on this Engine not sure where to start checking the MoFu out. The boat has been on Trailer for at least 5 years, maybe longer. The Engine appears to be a 1996-1998. Do not know when it was placed in this 1974 SkipJack. Any help to getting me started on this would be greatly appreciated. More detailed pictures of the Engine's Intake and Exhaust will be posted in the very near future. I have attached some general pictures of the Engine area just after I purchased the boat back in September 2006.

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:% Be Gentle Guys, I'm Sensitive. :% (Like that will mean anything :devil: )

 

[Bondo]

Re: Chevy Exhaust System

For the "Junkyard Dog" that it Is,..... It Don't look that Bad......

Looks the the Risers are Easy to get at,.... Pop 'em Off,+ Have a Look............

 

[bruceb58]

Re: Chevy Exhaust System

Sure looks like a newer style riser on it Also, looks like it has or had a water leak near the front. Could be leaky thermostat housing or water pump or just hoses not clamped tight.


Lyndy, where in LA are you located?

 

[Lyndy]

Re: Chevy Exhaust System

Sure looks like a newer style riser on it Also, looks like it has or had a water leak near the front. Could be leaky thermostat housing or water pump or just hoses not clamped tight.


Lyndy, where in LA are you located?

I believe it to have had a water leak at one time. During Sea Trials I notice no leaking. I will be Spray Painting the rust spots so I can keep an eye on them. The Boat is located in a Dry Slip at Marina Del Rey.

 

[bruceb58]

Re: Chevy Exhaust System

I go by there every day on my way home from work.

 

[Coors]

Re: Chevy Exhaust System

clean that rust stain, and verify leak is history

 

[Coors]

Re: Chevy Exhaust System

that blue tube from valve cover to carb, needs replaced

 

[Don S]

Re: Chevy Exhaust System

That blue tube from the bottom of the carb to a PCV valve in the valve cover shouldn't be there at all. The carb is probably automotive (Danger Will Robinson), from looking at the vent on the carb and the blue hose, and the broken section for the flame arrestor stud. you need a new one anyway.
Might look just above the starter and see if there is a metal tag with the Mercruiser SN on it. If you can get that number, I can tell you year and model of the engine.

 

[Lyndy]

Re: Chevy Exhaust System

I go by there every day on my way home from work.

Looks like we are darn near neighbors! I live and work in San Fernando Valley

 

[Lyndy]

Re: Chevy Exhaust System

The carb is probably automotive (Danger Will Robinson)

Already have a replacement just waiting to be installed.

Might look just above the starter and see if there is a metal tag with the Mercruiser SN on it. If you can get that number, I can tell you year and model of the engine.

Excellent! Thanks Don. I will looking close for it later today.

Carb Replacement in waiting

 

[bruceb58]

Re: Chevy Exhaust System

Looks like we are darn near neighbors! I live and work in San Fernando Valley

Chatsworth here!

 

[Lyndy]

Re: Chevy Exhaust System

Looks like we are darn near neighbors! I live and work in San Fernando Valley

Chatsworth here!

Work in Chatsworth and live in Tarzana

 

[Lyndy]

Re: Chevy Exhaust System

For the "Junkyard Dog" that it Is,..... It Don't look that Bad......

Looks the the Risers are Easy to get at,.... Pop 'em Off,+ Have a Look............

Here are pictures of the Junkyard Dog's Port Side Exhaust. What is the verdict?

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[Lyndy]

Re: Chevy Exhaust System

For the "Junkyard Dog" that it Is,..... It Don't look that Bad......

Looks the the Risers are Easy to get at,.... Pop 'em Off,+ Have a Look............

Here are pictures of the Junkyard Dog's Starboard Side Exhaust. What is the verdict?

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[Don S]

Re: Chevy Exhaust System

They don't LOOK too bad from here at first glance. May just need some now Mercruiser gaskets. (Not aftermarket)
What you really need to check is the gasket surfaces of both the manifolds and the risers. They need to be shiny METAL, not that black carbon looking stuff that they turn into.
And make sure they are flat.

Did you find a serial number on your engine?

 

[Boomyal]

Re: Chevy Exhaust System

Looks like we are darn near neighbors! I live and work in San Fernando Valley

Chatsworth here!

Work in Chatsworth and live in Tarzana

Wow Lyndy, I grew up on Avenida Oriente. Went to Taft Hi. Still have a good friend who lives up on the hill, above Reseda Blvd. My wife lived in Marina Del Rey when I met her.

Was down last June to show the kids where they were born and make the rounds in the Valley.

 

[Lyndy]

Re: Chevy Exhaust System

They don't LOOK too bad from here at first glance. May just need some now Mercruiser gaskets. (Not aftermarket)
What you really need to check is the gasket surfaces of both the manifolds and the risers. They need to be shiny METAL, not that black carbon looking stuff that they turn into.
And make sure they are flat.

Did you find a serial number on your engine?

Thank You Don! Can I locate the Gasket by using the Part# on the Riser?

There is some metal missing from the Elbow. Should that be a concern?

Is there specific Torque needed on the mounting bolts of the Riser when I put them back on?

Should the Rubber Hose connected to the Riser be replaced because of that split?

I forgot the serial number. I will get it this weekend. Do you think this is a Mercruiser Engine or just a Chevy Engine with Mercruiser Parts bolted on?

 

[Don S]

Re: Chevy Exhaust System

They are all Chevy engine, it's all the other stuff that makes them Mercruiser. They Thunderbolt ignition, the Mercruiser manifolds and risers, the brackets for alternators, ignition parts, tstat housing, heat tube to manifold is all Mercruiser.
If there is a Mercruiser tag above the starter, I would say it's an OEM engine transplanted to your OMC...... Poor engine :% :devil:

There is some metal missing from the Elbow. Should that be a concern?

Where and how much?

 

[Boomyal]

Re: Chevy Exhaust System

Should the Rubber Hose connected to the Riser be replaced because of that split?

If the split goes thru the clamp area, replace it.

You can also use a big flat file to clean the risor surfaces. Use your three fingers on top of the file, as you work it over the surfaces. You won't take of much of the very hard iron but it will clean all the gunk of and get you down to shiney iron to check the real condition of the surfaces.

 

[Lyndy]

Re: Chevy Exhaust System

Lyndy: There is some metal missing from the Elbow. Should that be a concern?

Don S: Where and how much?

Around the edge of the elbow just aft of the Port Riser.

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