newbie...running hot???

[34coupe]

hello everyone... i recently puchased a 93 crownline with 5.0 merc/alpha 1. Today on the water i took her out to the "speed" area and took a couple full throttle laps, which was all good!!! About 45 mins later after idleling around we decided to run her again, with in 45 secs she was running HOT, buzzer going off. So i killed the power back down to an idle and in seconds the temp began to drop back to normal!?! Tried speeding (full throttle) up again and temp went right UP! i ended up just idleling the rest of the day and no issues Any ideas what to check first?? thanks

 

[searay3]

Re: newbie...running hot???

If you haven't already, replace the impellor in the outdrive. While the outdrive is apart, chek the tube that mates upper to lower water passages. Sounds like when you are on plane the pump is the only part of the drive in the water and can no longer supply water to the engine. Once you stop it is fuly submerged again and can keep up. Impellor is a maintenance item replaced every two or three years.

 

[Gary H NC]

Re: newbie...running hot???

Sounds like the impeller was past due for replacement and now there are pieces of it blocking cooling passages in the engine,steering cooler or thermostat.

 

[34coupe]

Re: newbie...running hot???

thanks guys, thats exactly what someone told me at dinner tonight!!! is it something that can be done at home or do i need a professional to do it??? im picking up a book on mercs tomorrow! thanks again for the help guys

 

[jtmarten]

Re: newbie...running hot???

No reason to pick up the books. Download them from the adults only section.

 

[34coupe]

Re: newbie...running hot???

if decide to do the repair myself, do i have to remove the entire outdrive or just the lower unit itself?? local shops are booked for a week

 

[jtmarten]

Re: newbie...running hot???

You can replace it by removing just the lower unit.

 

[34coupe]

Re: newbie...running hot???

thanks jtmarten!!! i do all the wrench work on my cars, just never on a boat!! nervous. anything i should look out for??

 

[nuboat2me]

Re: newbie...running hot???

Having recently done this... When you put the foot back on, make sure the thottle is in F... Have plenty of paper towels handy too..

Good Luck!!!

While you are at it, you may want to change the lower unit lube...

 

[34coupe]

Re: newbie...running hot???

ok thanks...how far in the "F" should i go??? was lookin at it last night and couldnt seem to find a "drain" screw on the lower unit?? or will it drain itself when i remove lower unit??

 

[34coupe]

Re: newbie...running hot???

nuboat2me....is the lower unit "lube" seperate from the upper section(lube)?? i didnt have it in F postion when i removed lower unit will this matter???

 

[whit71]

Re: newbie...running hot???

Yes upper and lower have seperate oil resivoir. its very important to put it in gear BEFORE you remove lower unit. now that its off the lower unit is in neutral it needs to be in gear so you can turn the prop to line up the splines when you reinstall the lower unit. if memory serves the first time i changed a impellor on my old alpha ( I didnt put it in gear either) I used a long screwwdriver to put the lower unit in gear just take your time to look at the steped piece make sure if you put the lower unit in rev. you shift the controls in rev or if the unit is in fwd you shift control in fwd. get a friend to get in the boat and shift watch the shift arm if it goes down push the screwdriver towards the prop to put the lower unit in gear. Dont beat yourself up to much we all made mistakes on our first boats just learn from them..Good luck

 

[Eric 3.7LX Alpha 1]

Re: newbie...running hot???

Sounds like you have a Alpha 1 Gen 2, you should download the correct manual in the Adults only section at the top of the fourm. It covers everything you will need to know about the drive you have.

If it was me I would remove the upper as well so you can lube the u-joints, check the gimbal bearing, and see if the bellows is dry or any H20 in it which would be bad. Then you could properly grease the gimbal bearing while looking at so you don't completely fill the bellows with lube.

Grease the splines of the yoke and get er back together. You can just remove the lower but if you don't removed the upper and checked, things it will eventually catch up with you. Especially if this boat is new to you and you can not confirm maintenance from the past.

Good luck with it,
Eric

 

[34coupe]

Re: newbie...running hot???

thanks guys for all the info!!! looks like i have work cut out for me. i didnt place it in -f- before i dropped the lower unit!! and someone put one of those "mcgaurd" locks on one one of the out-drive bolts and i dont have the "key" to remove it..uugghhh!!!! well hopefully i can get the lower back together for the weekend!! then start on outdrive after.......

 

[34coupe]

Re: newbie...running hot???

well thanks to my father in law and your guys info we go it all back together tonight. actually wasnt as bad as i inticipated. going to the lake tomorrow to test......will let ya know