View Full Version : 3GM30 almost runs

06-10-2010, 09:59 AM
The engine ran away end of last season, due to fuel pump internal springs broken and dumping fuel. I had I.P. rebuilt. I have reinstalled and she starts and runs for 3or so seconds. like there is air in the sys. I have bled the syt, and am only trying to get her to run on the #3 cylinder. She wants to run and sort of does, for about 3 seconds, at which time she dies out. I can't imagine I still have air in the lines, bled and rebled. a mechanic aquintance of mine mentions I may have cracked the block from the excessive heat durring the runaway. It was very hot. couldn't lean on the crank case cover, hoses were very hot too. had to choke out the engine w/ a bilge plug to shut down. The shut down lever didn't work at that moment.
Any sugestions?? Thank you in advance, David...on the s/v Nico, alongside sav, ga.

exhaust elbo is clear. i have a dif manifold that I am checking to see how clean she is ineternally.
I have never opened the cooling water seacock untill engine is running, so not to fill engine w/ h20, hydrolift muffler and all. It has never been an issue inthe past...

06-19-2010, 03:45 AM
Why only run on cyl3?
Does it run if all cyl's are 'connected'?
If at all to be able to run on 1 cyl, the others must be decompressed.

06-26-2010, 08:54 AM
Okay, The engine runs. it was a gov thing. it was a big tear down to get to the bottom of the problem. Now I have seen what it looks like behind the timming case. I removed all pulleys and such to be able to do this, but this is what had to be done if i was gonna get this engine runnning. I took the gear case cover of the motor off the motor. once the front of the motor was removed you will see inside the removed in the cover is the throttle assembly as well and the gov sys. it took all day, making the adjustments i thought would do the trick and putting the engine back together, less the pulleys. by the end of yesterday I had the engine running!! she starts easier and quicker than my chevy stepside pick up truck does. I thank the God of creation for giving me the strength to perservere into and thru this issue! Thank you Jesus Christ!!!
and Haffiman37, thanks for your reply. i may not have done such a good job on the explaination of the first attempts to get this engine running, I wasn't understanding your post...I thank you for your input just the same.

The Yanmar lives!!!!!!