Timing on Mercruiser 5.7LX

foxtrap2452

Recruit
Joined
Apr 19, 2010
Messages
4
Attempting to check the timing on my 1997 5.7LX Mercruiser engine thunderbolt V system. Connected the purple lead to ground. Put the timing light lead on plug wire #1 but unable to see any timing mark on the balancer. There is a scale on the balancer but no tab. Also I noticed that plug wire #1 is at 11 o?clock on the distributor (upper LH), where according to the manual is should be at 4 o?clock looking from the front of the engine. I revved up the engine a bit and saw the timing mark just coming up from the opposite side of the balancer. Any info on this confusion would be greatly appreciated. I replaced the spark plugs, wires, distributor, filters etc. but the engine still runs a rough. I can manage to get 31 mph at WOT at 3600 rpm (that?s a bit low according to the specs.) The boat is a 1997 Bayliner 2452 with bottom paint which might take away a few rpm I?m told.
 
Last edited:

foxtrap2452

Recruit
Joined
Apr 19, 2010
Messages
4
Re: Timing on Mercruiser 5.7LX

I forgot to add that I adjusted the distributer until I ran out of adjustment at that point the rpm increased a bit and now I can just see the timing mark coming up from the bottom of the balancer. Still nowhere near the timing mark on the engine which is not a tab but a little mark on the engine itself.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: Timing on Mercruiser 5.7LX

You sure you have #1 plug wire? 1,8,4,3,6,5,7,2
front
1 2
3 4
5 6
7 8
flywheel
 

jack gardner

Seaman Apprentice
Joined
Aug 4, 2008
Messages
40
Re: Timing on Mercruiser 5.7LX

just a note 4 ease if u look stright down the front of the block one head will b ahead of the other that will b nu one cyl furthest head forward .hook ur timing lite too that wire and u r on nu 1 second i have seen those balencers spin they r set in rubble and can spin unusual but possible hope this helps
 
Top