OMC 140 O/Board

[joey1]

I have a 140 OMC outboard that has 115LBS of compression;I had a problem with it not running on one cylinder when idling but operating normally at full throttle. I replaced one coil installed new spark plug wires and new spark plugs,still no fix spark was a bit weak so I replaced the power pack. The spark seemed to have gotten a bit stronger but the engine still would not run on the cylinder. I checked the reed valves and found that somebody had worked on the engine and cracked the outer housing of the intake manifold. I repaired the crack and reinstalled the carburators now the engine will only run on one cylinder.<br />Any ideas.

 

[DIBOJOBID]

Re: OMC 140 O/Board

Hey Joey1, I've got an OMC Seadrive 140 horse on a Sportcraft 205. Maybe my post hasn't been posted long enough to get a reply,but I see a lot of problems with the OMC 140 and maybe everyone that knows anything about boating or outboards tries to stay away from these motors. I recently had my mechanic put a new coil and powerpack on my motor because he said that #3 cylinderwas dead.<br />Well it runs worse now with all cylinders suposedly firing. My max rpm WOT is 3800 and it gobbles gas. Lets wait and see if there is anyone out there with experience to give us some advice.<br />I'll be keeping a look out for your problem as well as mine.<br /><br />DIBO

 

[torxdrive]

Re: OMC 140 O/Board

well if you have compretion and spark then that leavse fuel i would look a the carb

 

[JB]

Re: OMC 140 O/Board

Hi, guys.<br /><br />You need to search this forum for power loss problems.<br /><br />Find out which cylinders are dead, find out if the problem is spark or fuel.<br /><br />Let us know what you find.<br /><br />Good luck.

 

[Dhadley]

Re: OMC 140 O/Board

Both style 140's are great motors. I suspect the first two posts are talking about one of each. The only reason, that I know of, people shy away from a 140 is because because they are looking for a V6. <br /><br />There is no reason that both motors wont run properly.<br /><br />Good luck!

 

[fishon71]

Re: OMC 140 O/Board

I ran a 1983 Johnson 140 for 5 years, it was almost 15 years old when I got it. Only replaced plugs a lot other than that ran for ever even after the boat sunk and it was full of salt water, couldn't kill it. The new owner is still running it today!

 

[DIBOJOBID]

Re: OMC 140 O/Board

Hey Joey1 sounds like you are stirring up some interest. I'm confident thet when the OMC power problem is fixed we will both be happy. Only question I want answered is what to try next.How do you test the stator for faults without buying a new one for $350. Reason I'm asking is an older post stated that a stator solved his power problem on his OMC 140 (1990 vintage).