OMC 3.8 Chevy 229 block cracked

Bondo

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I got number one cylinder right (after all the research). Watched as the valves opened and closed coming around to number 6 firing position and then no movement on compression for number 1. Guess I'll pull valve covers and watch as I slow walk the crank. Could be off but I did follow the instructions in the Clymer manual. adjusted intake 1,2,3 in TDC, exhaust for 1,5,6 and then rotate again to timing mark for intake 4,5,6, exhaust 2,3,4. Doesnt hurt to recheck :) Thanks guys :)

Ayuh,.... Did ya tighten 'em til the push rod didn't turn, or just til it stopped movin' up, 'n down,...

Study the Merc manual I linked to, rather than the knee pad you've been usin',....
 

omc_parted

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Jul 12, 2014
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Used the Merc manual, some were off a bit, but not anything crazy. Took all play out of rocker, then tightened one whole turn. Found a notch on the bottom of the distributor that matches a notch on the manifold, showed me I was way off, on the rounded cam of the distributor. Now it is where it belongs. Major ass pain dealing with this dizzy. Plug wires supposed to be here tomorrow. My next post should begin with something like "YAYYYYY!!!! :)
 

omc_parted

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Jul 12, 2014
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Valves were adjusted too tight. Followed manual to a T. (Set to 0 TDC, adjust exhaust 1,5,6, intake 1,2,3. One turn to number 6 firing pos, adjust remainder)
ALWAYS resulted in zero compression. Loosened all, got about 160-170 per cylinder. Adjust by eye and feel, much better results. Adjusting to end lash on each push rod, then add one turn did not work at all. After I get it running, will adjust once engine warms. My uneducated guess would be incorrect length push rods?, My cam is the original cam from the cracked block, lifters are all new, cam bearings were from 83 Caprice. Some combination of this must be wrong. Timing chain,sprocket all lined up at dot. Either way, the manual (Merc or OMC) did not work.

If I can get weather to cooperate, this beast will run this weekend. Below freezing currently. After this, gonna put away a little money so I can get the new exhaust manifolds from OSCO. Mebbe more e-bay options. Sierra wants too much per manifold, riser.
 

omc_parted

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Jul 12, 2014
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After thawing out the backyard spigot, got the weather to coperate for my water source. My timing/carb needs tweaking but success!
 
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Howard Sterndrive

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Nov 5, 2008
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cool!
I always do a final set of the valves with a compression gauge and a starter switch cranking the engine. I snug each nut down until compression drops off, then back it off until rocker rattles. Then i split the difference.

To have a valve not perfectly closing in some street rod is one thing. But with the continuous load in a marine setting, a valve not perfectly adjusted can be catastrophic to the valve seat and valve (and then it get's worse from there).
 

omc_parted

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Jul 12, 2014
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I kinda miss the old days working on VWs where you adjust it per feeler guage and yer done. Funny on these motors you gotta pull the starboard exhaust manny to get the damn valve cover off :) Think I lucked out not busting a valve when too tight. Gonna warm her up mebbe this week and do a final tune up. Then its on to rebuilding the stringers as needed. The motor mounts are gone (under the trim mounts). Any suggestions?
 
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