Over Heating

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
1988 305(5.0) alpha 1 , Replaced the impeller in May.

Since then I have put about 20 hours on the boat, and everything great, boat ran great.

Boat sat on my drive way for about a month, been busy, and could not use it.

Went out today, immediatly had trouble with overheating when i put it in the water. (Of course i thought my guages were wrong), but then realized with in about 5 minutes, engine overheating. Hopefully I didnt damage the engine.
Opened the water jackets, and no water came out.

Now I took the bottom end off, and looked for a bad impeller, and impeller looks fine. Plastic tube around the copper tube that looks like it flows the water into the ingine is melted at the top. Looks like things got hot down here, and I dont know why. Never had any trouble till now. Little rubber O-Ring on drive shaft looked burned also.

Wondering if anyone has seen this before?
 

jtybt

Senior Chief Petty Officer
Joined
Aug 5, 2009
Messages
730
Re: Over Heating

When was the last time you replaced or cleaned the risers?
 

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
Re: Over Heating

Been looking in my manual for the procedure on that, and i can't seem to find anything on it.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Over Heating

Time to pull them apart and inspect.
Forget cleaning, if they are plugged up replace them, if you just clean them you will find that most of the crud in the manifolds is the manifolds and risers themselves corroding away. Your next problem could be water in the engine and loose your engine. Because you failed to heed the warning of the rust to replace the manifolds and risers.
 

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
Re: Over Heating

I have the Seloc Mercruiser , Stern Drives 1964-91 Repair Manual
 

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
Re: Over Heating

The last time about a month ago, i ran the boat thru heavy algie. Then the boat sat for a month. Could this have possible plugged things up?
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Over Heating

I have the Seloc Mercruiser , Stern Drives 1964-91 Repair Manual

What a waste of money. Go up to the adults only and download the OEM manual for your engine and drive.

The last time about a month ago, i ran the boat thru heavy algie. Then the boat sat for a month. Could this have possible plugged things up?
Could be, time to start looking.
Start from the drive and work your way to where the water comes out the drive. Somethings plugged up.
Especially look in the power steering cooler.
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Re: Over Heating

Hey, not to hijack, but I have similar boat & year. It's new to me this year.

Do you recommend pulling risers & if I find any crud change exhaust manifolds?
 

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
Re: Over Heating

Well i am feeling as little silly now. The hose that feeds to water to the moter, (kinda hidden up and over from the exhaust bellow was disconnected.

Kind of upsetting since I paid a marine outfit at the beginning of the season to remove my outdrive and service it. I was planning on doing it my self, but they scared me into thinking that somehow i needed a special tool to put the outdrive in at the proper angle or i would cause major damage.

The hose clamp looked bent, and looking at it,,, it looked a little stripped.

I'm going to get a new hose clamp, and hook it back up and i am guessing this will be the fix. Am i supposed to buy some type of bellow glue on it with the hose clamp?
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Over Heating

All the exhaust hoses from the risers to the Y pipe are probably burned up inside and will leak. The exhaust shutters are probably gone or melted also.
 

Rippin_54

Seaman
Joined
May 11, 2007
Messages
65
Re: Over Heating

All right, after reading up on all this, I have a better grasp of the terminolgy.

I pulled off 1 riser and inspected it. Now I have never seen a bad riser, but it look fine, a little bit of rust which i scraped out, but besides that fine.
The boat only has about 150 hours on it

Question 1, do I have to get new riser gaskets? or can i reuse the old one. It came off fine.

I inspected the exhaust hoses, from the outside, they look perfect. Looking at the one just above the flaps, its a little crusty on the inside, but i think it will be fine.

Now the flap, it is half rubbery, and half shiny, and I am guessing it is supposed to be all rubber?

I am quessing the other side will be the same, so as of right now, I am going to get some new flaps, and maybe I got lucky on no engine damage.
 
Top