3.0 1989 Omc cobra engine problems

[Vintage Boat Guy]

I bought a 17' 1989 Tempest boat with a 3.0 Omc cobra in it. Ran good until the outdrive gave up. I rebuilt the outdrive, rebuilt the boat, and now all of a sudden Iron Duke is more like Lead duke. Every time I give it, it tries to go then threatens to stall, then repeats process. So I cleaned the carb and fuel pump, replaced the coil and plugs, it already had a new distributor cap wires and all that stuff. Now it won't even fire. What is wrong? I was wondering if the timing chain broke or something.

 

[alldodge]

Re: 3.0 1989 Omc cobra engine problems

Think I would start with a compression test

 

[Bondo]

Re: 3.0 1989 Omc cobra engine problems

I bought a 17' 1989 Tempest boat with a 3.0 Omc cobra in it. Ran good until the outdrive gave up. I rebuilt the outdrive, rebuilt the boat, and now all of a sudden Iron Duke is more like Lead duke. Every time I give it, it tries to go then threatens to stall, then repeats process. So I cleaned the carb and fuel pump, replaced the coil and plugs, it already had a new distributor cap wires and all that stuff. Now it won't even fire. What is wrong? I was wondering if the timing chain broke or something.

Ayuh,.... That sounds like a fuel delivery issue, or Water/ crud in the fuel that is delivered,....

Are the spark plugs, Sparkin',..??

Is there gas goin' down the carb's throat when ya try startin' it,..??
Is the choke set,..??

If it's any deeper than that, a Compression test might point the way,...

 

[Vintage Boat Guy]

Re: 3.0 1989 Omc cobra engine problems

Oh its has plenty of compression. Might be the carb still giving me trouble. The boat is 5 hours north of me now so I can't go check it, just wanted to know for spring. There is spark.

 

[Bondo]

Re: 3.0 1989 Omc cobra engine problems

Oh its has plenty of compression. Might be the carb still giving me trouble. The boat is 5 hours north of me now so I can't go check it, just wanted to know for spring. There is spark.

Ayuh,.... Did ya actually tear the carb down, 'n clean it,..?? aka; Rebuild it,..??

It sure sounds like a carb problem the way ya explain it,...

Btw,...... Yer motor Ain't the Iron Duke,.... quite different actually, pretty much No parts interchange,...

The Iron Duke is the 151cid, 2.5l Pontiac motor, that became GM Corporate 2.5l mainstay automotive motor,...

Our 2.5l, 'n 3.0l motors have their roots in the I6 Chevy of the very early '60s,...

 

[Vintage Boat Guy]

Re: 3.0 1989 Omc cobra engine problems

I was told they were called Iron Duke, I took the carb apart and cleaned it out, but I didn't replace any parts. I may take it off when I go up north next and rebuild it down here.