2002 Mercruiser 5 liter MPI Distributor Timing

joedm2000

Seaman Apprentice
Joined
Jun 21, 2020
Messages
38
And are you sure that the intake bolts were torqued properly and you don’t have a vacuum leak?
I was very careful in torqueing the intake bolts. Followed the Mercruiser Shop Manual word for word. Thanks....I will check for a vacuum leak. I have not checked that.
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
12,652
That's a good point. And be aware that Vortec intake screws are set WAY lower than non-vortec. I've seen more than one engine messed up because the intake screws were over tightened. (leads to leaks in the gaskets...)

Chris.
exactly the gaskets are very different and more prone to damage from over torquing. the pre vortecs rarely if ever leak...
 

joedm2000

Seaman Apprentice
Joined
Jun 21, 2020
Messages
38
Thanks, issue with that is if the damper notch can be a few degrees off. To make sure its a true TDC would need a stop bolt or a micrometer probing the top of the piston.

Your motor is running and with that as @Fun Times mentioned in the other thread, loosen the Dizzy and ever so slightly more it just a few degrees (really small amount) and lock it back down. Take it out and see how it does. If it gets better but still not right, try to go a hair more. If it gets worst go the other direction

The SB below is how to adjust and if need be to make a cheap tool to get the timing exact
Got out on the water tonight and it appears the issue was timing. I did also replace the plugs, distributor cap and rotor to be safe, but moving the distributor around fixed the problem. Thanks!!
 
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