OMC 5.7L owners

[prettybeatup]

I just purchased a 1988 deck boat with an OMC 5.7L engine. The fact that it was older was offset by the price and by the excellent condition of it. I have noticed however the tilt mechanism works fine but the trim however, doesn't. Are there separate motors for each mechanism? When I engage the tilt, it is silent so I'm assuming there is no electrical connection.
Second, no reverse...the seller told me it is a broken cable but the marine mechanic thought there was more to it. Other than those couple of issues I do enjoy the boat and it does get a lot of attention on the lake since the hull is quite unique and sets itself apart from the others. Thanks in advance for any tips or suggestions. And if you have any fyi for this engine please fire away.
Anton.

 

[LAC_STS]

Re: OMC 5.7L owners

First off I would get an OEM manual. Not a Seloc or Clymers but a real OMC one. You'll have to look on eBay or online.

I assume if it's an 88 it's a Cobra drive? My Cobra drive is a 88.

Not going into reverse should be looked at before you operate the boat. I dunno if it could be a shift cable but I've read alot of places that the cobra drive is susceptible to shredding gears or breaking if the shift cable is not connected and working properly.

Look at your shif cable that goes from the engine to the drive. If it's black it's the original and needs to be replaced anyways. If it's red it's a newer stlle but may still need to be replaced.
Do some searching on here and you will find tons of info on the 5.7 OMC.

There is a site called Hastings something. Google it
That's your source for shift cable info and some drive info. (besides your OMC manual)

 

[prettybeatup]

Re: OMC 5.7L owners

Sorry for the lack of info...yes it is a cobra outdrive. The previous owner stated he had the leg rebuilt about seven years ago so I'm assuming that was related to the infamous problems associated with the drive. To be safe I will have the marine mechanic check out the cable when he winterizes it next week. The colour code tip for the cable is a very good one. Thanks again to those who responded to my dilemma.
Anton.

 

[john744]

Re: OMC 5.7L owners

Hello prettybeatup and welcome to the Cobra World. I own a 1986 Cobra 5.7 and although I've had a few problems, I think it's a well designed drive (for the year it was designed). Changing the water pump impeller is a snap and you can do it in the water with ease! But, to the point. Do yourself a favor and get an OMC Factory Service Manual as LAC_STS said. The SELOC & CLYMER manuals cover a wide range of drives (years) and can cause a little confusion. Also get a PARTS MANUAL. These are readily available on EBAY.

I can't Stress this enough - You MUST MUST MUST MUST go to Stuart Hastings Cobra web site and read it in it's entirety! ! ! ! You will be doing yourself a great injustice if you fail to do this (and hey, it's free). Stuart has done an excellent job of explaining in technical and historical detail how & why the Cobras misbehave when it comes to shifting and forward or reverse problems. Reading his material will help you fully understand what's going on and is useful to any mechanic that might service your boat and is not thoroughly familiar with OMC Cobras. Then, read my post. I had a peculiar shifting problem with my Cobra. I finally resolved it by installing a new cable, but the malfunction was unusal. Interesting read with some enlightening photos. Good Luck!

 

[LAC_STS]

Re: OMC 5.7L owners

Can you really change the impeller in the water? I didn't know that that's cool if you can.