OMC Cobra 5.0 stalls when shifting into gear, and squeals

Todd in NY

Petty Officer 2nd Class
Joined
Jun 15, 2015
Messages
157
I've had the boat out 3 times this year (just bought the boat last month). The motor is only 2 or 3 years old and it just started giving me problems yesterday. It idles fine, but when shifting into forward or reverse it stalls, then it has trouble starting again. This is with a warm engine because I let the engine warm up before pulling away from the dock.

Another issue just started yesterday was a loud squealing noise when moving the throttle to a higher RPM and raising and lowering the outdrive. It has power steering but the fluid level is good. Once I finally got the boat out for a day of trolling yesterday on Lake Ontario it ran great. But when I was moving at idle speed in forward and tried to raise and lower the outdrive a little (near the dock), it started squealing real bad again. I'll check the belt tension today because I didn't have time to check anything yesterday. These problems just happened for the first time yesterday, so it really caught me off guard. Thanks in advance for any advise!
 

vasy

Petty Officer 2nd Class
Joined
Dec 14, 2014
Messages
193
You have to find where the noise is coming from. It could be that your trim pump is low/out of fluid. It is usually located on the transom and uses a different fluid reservoir.
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,478
The squealing is your alternator belt when you put a high electrical load on it by using the tilt.
 

Todd in NY

Petty Officer 2nd Class
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Jun 15, 2015
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157
Thanks for the feedback. So far all I have had time to check was the trim/tilt fluid level, which was 10 ounces low. I added fluid tonight and bled the trim/tilt system, and I will check the alternator and belt tension tomorrow. The power steering fluid level is good. I'll report back after I check belt tension and the alternator. The belts look new, so that's not an issue. I will check the belt numbers to make sure the correct belts were installed.
 

Todd in NY

Petty Officer 2nd Class
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Jun 15, 2015
Messages
157
I replaced the alternator belt and power steering belt, the squealing stopped.

I fixed the motor stalling issues by replacing the entire shift mechanism, shift cable and throttle cable. They were all original to the boat (1987) and were badly worn.
 

Pete104

Lieutenant
Joined
Apr 30, 2011
Messages
1,439
Thanks for the update! Glad you found time too give it some lovin'! :laugh:
 

Todd in NY

Petty Officer 2nd Class
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Jun 15, 2015
Messages
157
This old boat is my pride and joy. I try to remember to give updates in case someone else has the same or similar issue. It was too much for me to do myself so I paid a local marina to do the shifter and cable replacement for me. The motor was replaced a few years before I bought the boat and the original belt part numbers are not correct for this newer motor. Luckily my local marina had the belts I needed.
 

vasy

Petty Officer 2nd Class
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Dec 14, 2014
Messages
193
Do you have the part numbers used for the belts?
 

Todd in NY

Petty Officer 2nd Class
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Jun 15, 2015
Messages
157
Oh, I had them on my phone. My engine model number (the original engine) was 504APARY, 1987 5.0L OMC Cobra. The listed power steering belt still fit, it is part # 3852464. The listed alternator belt was way too long, and it was part #3852504. So the dealer gave me a random belt, part #3853713. It was a real tight fit to put on, but it's been trouble-free since I changed both belts. When I bought the boat it had NAPA belts on it, and I didn't know how old they were, or if they were marine grade belts. But those NAPA belts were the ones that were squealing. Hope this helps, Vasy.
 

vasy

Petty Officer 2nd Class
Joined
Dec 14, 2014
Messages
193
I put new belts on my boat, some car brad and all was ok at start but now the squealing is driving me crazy.
Will try Volvo belt this time.
I kinda though a belt is a belt you know... :)
Thanks
 

Todd in NY

Petty Officer 2nd Class
Joined
Jun 15, 2015
Messages
157
Apparently not, according to my original OMC owners manual. It says that marine grade belts are more high performance because of how hard we push our boat motors. It makes sense though, because I dont run my car or truck motor at 2/3 to full throttle like I do my boat motor. That puts a lot more stress on all moving parts.
 
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