Mercruiser 3.0 1988

[alpha-newbe]

manuals are copywrite protected

you can buy used on ebay.

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I believe its manual 10.

View attachment 408354

I am having a tough time finding timing gear set for the Mercruiser 3.0 any ideas on good sources for engine components. Also water pump.

 

[Scott06]

I am having a tough time finding timing gear set for the Mercruiser 3.0 any ideas on good sources for engine components. Also water pump.

MerCruiser Motor Parts at MarineEngine.com

Buy from the largest online inventory of genuine MerCruiser stern drive parts including discount aftermarket parts. New and vintage parts available at MarineEngine.com.

www.marineengine.com

that splash page you can put your serial number in on left side or search by engine type and year. you can buy all parts that are still available there.

Not the best place to buy internal engine components but you can get them. The engine (3.0) is a GM/Chevy industrial engine , never went in cars. It is a descendant of the Chevy 2.5/153 CID 4 cylinder that was introduced in the 1962 Chevy II/Nova.

So if you find a good autoparts place like NAPA or summit racing with a good parts guy you can find them but you aren't going to be able to put in a car year and model

 

[Scott Danforth]

the motor is a GM 3.0 industrial motor. it shares timing gears with the 2.5 liter (153 cubic inch) 4-cylinder and the 196/230/250/292 inline 6-cylinders

just do a google search for GM 3.0 marine water pump.

 

[alpha-newbe]

Thank you for your suggestion about removing the drive. The sound could be transferring into the engine possibly. I will be scoping through the spark plug holes tonight just to take a peak.
I can run above idle speed and the noise does not always occur.
This is a tricky sound do to its intermittent behavior.

I truly appreciate your help and insight.

View attachment Waterpump 3.0-Mercruiser.mov

 

[alpha-newbe]

still not sure if the drive is up or not.... if up just trim the drive down and run it at that speed first see if the noise goes away.

re the comment about timing chain - the 3.0 uses a timing gear set

View attachment Waterpump 3.0-Mercruiser.mov

 

[alpha-newbe]

Thank you for your prompt reply,

I did go to mercury website and entered my serial number, no luck on the manual for some reason.

I am in the midst of a rattle sound that does not change with the RPM's. It is intermittent and generally starts at 2500 rpm. Then will stay clattering randomly as I decrease rpm. Then all of a sudden it will stop and I can rev the engine and it runs super smooth. But ultimately the engine runs extremely will other than this clattering sound. The engine does not appear to be bothered by the sound as it stays running smooth other than my concern for the noise.
View attachment 408340

Thank you for your prompt reply,

I did go to mercury website and entered my serial number, no luck on the manual for some reason.

I am in the midst of a rattle sound that does not change with the RPM's. It is intermittent and generally starts at 2500 rpm. Then will stay clattering randomly as I decrease rpm. Then all of a sudden it will stop and I can rev the engine and it runs super smooth. But ultimately the engine runs extremely will other than this clattering sound. The engine does not appear to be bothered by the sound as it stays running smooth other than my concern for the noise.
View attachment 408340

 

[alpha-newbe]

Turns out it was the Water pump. Thank you all for your suggestions.
Ran it without the belt for a very short time to isolate the accessories.

Once belt was off the noise did not happen any more.

So took off water pump to see what was inside and making the noise.

Check out the video and see for yourself.

Thank you all again,