OMC Cobra 140 Manifold Question

[Mr Wubbs]

I have been experiancing operating issues with a 87 OMC 140 that has been completely rebuild by a reputable shop. I am leaning to a cracked intake/exhaust manifold. I am looking for the proceedure to check if it is.
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If you do not see a crack in the 140 manifold, but have a continuing mis in the running of the motor.........is it possible there is an internal crack?

I replaced the motor in my boat due to the previous owner not winterizing, the block was indeed cracked.............however the manifold did not show a crack visually.

I now get a mis and a complete shut down after the engine has run for 45 mins to 1 hr. EVERYTHING has been replaced ingnition and fuel wise. I am running out of reasons this motor only runs short time. (I am also running out of money too)

Anyone have an idea?

THANKS IN ADVANCE !!!

 

[fishinpa]

Re: OMC Cobra 140 Manifold Question

What would make you think this is a crack in ( the intake or the exhaust manifolds ) ??

have you done any troubleshooting to see if your fuel and electrical are all operating properly ??


fish

 

[cperna15]

Re: OMC Cobra 140 Manifold Question

well if there is a crack i have an extra manafold that has just been milled. ill sell that and a holly 2 bbl carb for under $75. cperna15@gmail.com

 

[Mr Wubbs]

Re: OMC Cobra 140 Manifold Question

I have done the following trouble shooting,

Drained fuel tank
Replaced fuel pump
removed anti siphon valve
All new filters
Rechecked rebuilt carb
checked ignition switch and wiring
new coil and distributor
disconnected tach
checked resistance wire
cleaned all multi pin connectors

 

[Rich15R]

hydrolocked

hydrolocked

I am new to this boating and I love it when it happens however we have a 1998 Reinell that needed alot of work it was locked up when we bought it, big mistake.
Anyway I bought a running used motor out of a chevy, new manifolds (OMC) and just about everything else took it out a couple of times ran great at 180 degrees. Parked it for a few weeks took it back out on a Friday morning and it hydrolocked!!!! When I got it home took out the last 2 plugs on each side of block and guess what ????WATER!!

It has never ran over 180 so I am at a stand still at this point I dont know what else to do ????

Any suggestions would be great'


Thanks
Rich

 

[Levinz11]

Re: hydrolocked

Re: hydrolocked

^^^^^Start a new thread Rich^^^^^