OMC Cobra died at WOT - Help!

M

marunr

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Re: OMC Cobra died at WOT - Help!

I had the exact same problem on the exact same engine. It happened right after a tune up also and it turned out to be a faulty condenser. Do you still have the old one?
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

marunr said:
I had the exact same problem on the exact same engine. It happened right after a tune up also and it turned out to be a faulty condenser. Do you still have the old one?
Click to expand...

Wow, that would be crazy if its it. I do have the old one, and points. I will swap them in. I just got done setting everything back to TDC and checking everything.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

put the old points and condenser in and it will not fire. I put it on tdc maybe im 180 out?? I about to go get a new belt and see if that helps. Its weird now when you rotate the cam gear the distributor comes to the same #1 spot every rotation, is that normal?
 
P

PBKboater

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Re: OMC Cobra died at WOT - Help!

With dist cap off, can you turn rotor by hand? Seen it twice in my lifetime so far! Dist shaft turning rotor but slipping. Easy check also! Just a thought!

Paul
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

No its solid. Still can't figure it out yet, no new timing belt. But about to replace it.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

About to go buy a new belt, and maybe a condenser. Can't really think of what to try next.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

Got it half running again by putting everything back to tdc and I changed the condenser back to the new one. The engine sounds worse as you try and run it, it seems to drop timing as the engine runs... I am thinking stretched belt, so I am going to try a new belt and maybe another new condenser to test with.

Is there any cheap kind of automotive coil I can test with?
 
bruceb58

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Re: OMC Cobra died at WOT - Help!

What is the timing doing during all of this? You have a timing light right?

How far does the timing advance at high RPM?

Did you measure the dwell with a dwell meter??

A timing belt is not going to stretch enough for you to notice at idle.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

bruceb58 said:
What is the timing doing during all of this? You have a timing light right?

How far does the timing advance at high RPM?

Did you measure the dwell with a dwell meter??

A timing belt is not going to stretch enough for you to notice at idle.
Click to expand...

Well it drops BTDC and is retarded sounding... I try to advance it and its not enough it keeps dropping and finally stalls out. I cant even rev it up just idle if anything. No dwell meter yet, cant get it to run right at all yet.
 
bruceb58

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Re: OMC Cobra died at WOT - Help!

Baylinercapri1987 said:
Well it drops BTDC and is retarded sounding.
Click to expand...

Do you realize that BTDC is on the advanced side. Are you setting your timing BTDC or ATDC?

Also, you can set the dwell with a dwell meter without the engine running.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

bruceb58 said:
Do you realize that BTDC is on the advanced side. Are you setting your timing BTDC or ATDC?

Also, you can set the dwell with a dwell meter without the engine running.
Click to expand...

Sorry Must be going ATDC then... I put a new timing belt on, started it....sounds good....look at timing..adjust...set to 10...timing starts going down the grid...engine starts running rough..... almost stalls and I turn it off. I found a 50 amp fuse that was blown, one of the mains...could that do it?? Took the aux shaft out and inspected it...looks good.
 
bruceb58

bruceb58

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Re: OMC Cobra died at WOT - Help!

What RPM are you setting the timing at? It almost sounds like you are setting the timing at a, higher than idle, RPM and then, when the engine slows down, the timing starts to retard...which would be totally expected. You need to make sure the timing is set at idle RPM so that the distributor centrifugal advance has not come into play.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

Trying to time it at idle. Like 500-1000 rpm. The timing is really just dropping as the engine rotates at idle, I was watching it drop on its own over a minute period of running, thats all the running I can get out of it... I have to realign the distributer to get it to run again. I hardly have time to even set the timing, about a minute and the engine is mis-aligned and timing is to low to run. Thinking about buying a new distributer & aux shaft but they look good and are $330 new. I am at a loss still here....?????
 
a70eliminator

a70eliminator

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Re: OMC Cobra died at WOT - Help!

Baylinercapri1987 said:
Trying to time it at idle. Like 500-1000 rpm. The timing is really just dropping as the engine rotates at idle, I was watching it drop on its own over a minute period of running, thats all the running I can get out of it... I have to realign the distributer to get it to run again. I hardly have time to even set the timing, about a minute and the engine is mis-aligned and timing is to low to run. Thinking about buying a new distributer & aux shaft but its only $330. I am at a loss still here....?????
Click to expand...

Wait right there, your saying you have to re-align the distributor to get it to run again? that tells me your distributor isn't locking down not staying put now wonder your timing drifts out of range! now if it's doing this internally then you have a spring busted off the advance plate or something else up with the breaker plate, you can take it apart easy enough to check.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

a70eliminator said:
Wait right there, your saying you have to re-align the distributor to get it to run again? that tells me your distributor isn't locking down not staying put now wonder your timing drifts out of range!
Click to expand...

Yes, it moves back near # 2 usually when I was testing. I lock it down when running...Then loosen it just so I can move it around and try and to time it. I really don't think its moving. The distributer moves in a way that it gets not time-able...starts to hit the alternator and you can not adjust it anymore and the timing goes further down by itself. I should post a video tomorrow of it running...
 
bruceb58

bruceb58

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Re: OMC Cobra died at WOT - Help!

Sounds like a broken or loose spring in your distributor centrifugal advance mechanism.
 
Baylinercapri1987

Baylinercapri1987

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Re: OMC Cobra died at WOT - Help!

Here it is... Is that the springs?

006-8.jpg


005-12.jpg


007-7.jpg
 
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