88 7.5L 460 OMC outdrive will not idle

[rv2008]

Hello,
I have the above engine and O/D. Has 5 hours on rebuilt engine. When I got it, it had been setting for 2 years. I changed out the batteries, checked the oil(it was clean). Tank was empty. Put in some fuel, new fuel filter/water separator. Cranked it and although it did crank it would not start. I pushed the throttle up a little and it started but revved high so I moved it back to "start" quickly but it died. Could the carb just need to be cleaned/rebuilt? Any suggestions?

 

[rv2008]

Re: 88 7.5L 460 OMC outdrive will not idle

Thanks for the info. I will try it tonight. It is kind of difficult to keep it relatively low though. It wants to rev pretty high. One extreme to the other.

 

[PINESOL]

Re: 88 7.5L 460 OMC outdrive will not idle

first of all .... welcome to iboats ..
second , could be a possible vacuum leak .. that will cause a high rpm problem ...
third , in case you are new to boats .. make sure that when your running it in the driveway you have the outdrive in the down position and hooked up to the hose .. and like bubba said ... it may just need to run for a few minutes .. keep an eye on all your guages ... dont let it get hot ...

 

[PBKboater]

Re: 88 7.5L 460 OMC outdrive will not idle

Welcome to iboats! I agree with Pinesol, most likely the carb to intake manifold gasket is all dried up and leaking along with old fuel left in carb gumming up idle circuit etc.. I also have a 1988 OMC 460 I just rebuilt and in the process of breaking motor in. (so far so good) If you have any questions on where to get parts I can be a help possibly.

PS: A full tune up couldn't hurt!

and good luck with your new boat,
Paul

 

[rv2008]

Re: 88 7.5L 460 OMC outdrive will not idle

Thanks everyone for the info. I was able to get the engine to idle. I got some carb cleaner and sprayed down the carb real good and let it dry and it started right up.

I need to get the moisture out of the tank but it ran great. It would occasionally sputter but overall it idled great.

Thanks again.

What would you do about the outdrive. It has been setting for 2 years. The previous owner suggested I at least change out the upper boot (I forget the correct term. the corrugated black rubber tube covering the nuckle) and get it checked out overall.

rv

 

[thedillybar]

Re: 88 7.5L 460 OMC outdrive will not idle

For the outdrive
1) Change the oil. If it has lots of metal pieces in it (some are normal), you need to take it apart and look at the gears, shaft, u-joints, bearings. If it's white/milky, you need to wonder how water got in (might just be condensation from sitting for so long, or could be the upper bellow you're talking about; need to look at gears, shafts, u-joints, bearings for corrosion).

2) Check the oil after your first few times out. If it's a little low, no big deal. If you're losing a lot, probably a bad o-ring somewhere. If it's white/milky, probably the upper boot is bad and everything should get looked at.


My (relatively unexperienced) opinion is to check the boot & lower unit oil often (every couple of trips), but not to bother changing unless there are signs of damage (leak or boot is beginning to crack). I'm sure someone who has had one go and had to replace everything has a different opinion.

 

[rv2008]

Re: 88 7.5L 460 OMC outdrive will not idle

Thanks dilly,

Would you attempt to change the bellow or would you have someone do it for you? I am mechanically inclined but have no experience on outdrives. I also do not want to jeopardize safety.

Rick

 

[thedillybar]

Re: 88 7.5L 460 OMC outdrive will not idle

(This is for Mercruiser alpha ones...)

I've never done it, but...it sounds like a somewhat involved job. You have to remove the pivot pins that attach the bell housing to the gimbal. And the hardest part seems to be getting the stubborn bellow attached to each side w/o the special Mercruiser bellow expander tool. The solution that sounds best to me is to leave the bellows in hot water for a while before installing.

And this is the most straight-forward instruction guide I have found.
http://www.boatfix.com/how/outdrives.html

Good luck!

 

[rv2008]

Re: 88 7.5L 460 OMC outdrive will not idle

Thanks for the info.

Not sure I want to tackle it.

 

[bomar76]

Re: 88 7.5L 460 OMC outdrive will not idle

(This is for Mercruiser alpha ones...)

I've never done it, but...it sounds like a somewhat involved job. You have to remove the pivot pins that attach the bell housing to the gimbal. And the hardest part seems to be getting the stubborn bellow attached to each side w/o the special Mercruiser bellow expander tool. The solution that sounds best to me is to leave the bellows in hot water for a while before installing.

And this is the most straight-forward instruction guide I have found.
http://www.boatfix.com/how/outdrives.html

Good luck!

Well, he has a OMC, not a Merc, he was asking about the drive bellows, and the bellows tool is only used on the Mercs for installing the EXHAUST bellows...so none of this advice applies at all.