Engine Leaking Water
 

so i just fired up my boat after being stored all winter (yes winterized). it fired right up, but it began streaming out on both sides of the engine (mercruiser 350 magnum - carb"d) behind the exhaust manifold. it doesnt look like a cracked block as it is happening on both sides in almost the same place. no, i didn't forget to put plugs back in, but it seems that there could be a gasket that needs replacing maybe??? please let me know any thoughts- thanks!

Freeze plugs?

First identify where exactly the water is coming from. Take a picture and post it up if possible. If you can not see it directly use a inspection mirror/dental mirror to locate the leak.

^^^ +1

so this is the best one i could get because of the tight fit. it's coming out about a half inch under the valve cover and seems to be behind a gasket, but couldn't really tell. on the left is the valve cover, the right is the manifold. i'll try to get a better shot of it tomorrow in the light.

looks like block drains or manifold drains

OP states, "no I didnt forget to put plugs back in".

does not mean he seated them right

My drain plugs are brass and tapered. Nothing to seat. Thread sealer and tighten them up.

post serial number

I have checked the drain plugs, and all are tight, and not leaking.
serial #D815238

here's 2 pics

In the next to the last pic. Can you edit the photo and circle the area where the water is leaking from. Kinda looks like the riser gasket may be leaking.

i would pull all the plugs on the side of the engine and check to see if they are wet and if any water is in the cylinders. also check to see of you have water in your oil. if so you probably have a blown head gasket.

you need #17 manual for merc

looks like a riser gasket

well, i had time tonight to pull my exhaust manifold...no bueno. i found out that i have a crack in the head. the other side is about the same. this really sucks. i now get to source new heads. any advice now???

http://www.acheinc.com/

http://www.usengine.us/

http://www.marinerebuilds.com/

also napa auto can get sierra heads

Jegs.com and get some performance cast iron heads. Your already there might as well get a little more hp while your doing it. You could even do a set of aluminum heads like the indmar 340. Just a thought.

due to a busy work schedule this is the first i've been able to get back to this project- so i was able to call a local service shop and the service tech said that if my heads are leaking that many times it means that the valley thru the intake is likely cracked as well. i'm trying to not have to pull my intake (cuz it looks like a pita) but will if i have to. my question is, is it a typical scenario to have both of these things occur? should i just bite the bullet and remove the intake. lookin for some advice-

You have to pull the intake to pull the head off.

sweet. sounds like i'm doin that tomorrow. thanks aaron.

Liek Aaron said, the intake manifold has to come off to get to the heads. Once you remove the carb and distributor, the intake is very straightforward, just remove the bolts and lift straight up. For the heads, you have to remove the rocker arms and push rods (keep these in order so the same ones go back in the exact same places if you re-use them) and then unbolt. There are I believe 4? rows of bolts 3 inside the head and one outside? might be just 2 inside I cant remember.

Removal is the easy part, putting it all back together is where it gets fun.

Oh, put a mark on the dizzy and the intake to help with re-alignment when you re-install. Should help get your timing close to start with.

just put it all to TDC before you remove the heads and that will help to make sure you have proper timing on reinstall.

You do not have to pull the rocker arms completely off. I would also leave the carb on to. Keep in mind if you pull one head and find the head gasket is blown. Don't assume the other side is good. Replace both head gaskets at the same time. Depending on your skills this is a half day job. Sounds like your first time so one or two full days. I would gather all your supplies first from any local auto supply. Oil,filter, head gaskets( fel-pro blues) intake gaskets (fel-pro blues) exhaust manifold gaskets, Teflon sealant for head and intake bolts and permatex gasket sealant. Do not use the gaskets for the intake at the front and back of the block run a THICK bead of the permatex. To make it easier on you I would mark the plug wires at the end going to the spark plug so you will know which ones go where. Leaving them attached to the distributor cap. once you pull the cap and wires bump the motor until the rotor is in a good spot for reference you need to reference the distributor housing as well. With this and every thing mentioned by every one else. You should have a good start.

Bummer. If the boat was winterized, how did this happen??

FREAK

a vacuum gauge tells a lot at idle



99 gots good points, Especially the intake gasket, front and back, use FACTORY INTAKE GASKETS!!, they have rubber unlike cars, plus u need to run gasket sealer up the sides of intake gaskets to make a seal

but no need to bump motor over until dizzy back in

if you have no clue, pass this on to a good shop

if your torque wrench is off, your motor could try to compress water, which will bent a valve and/or rod, and thats not fun!!!


Bummer. If the boat was winterized, how did this happen??

hahhah

you really want to know how many shops do not WINTER-IZE correctly???


I bet over 80%

one thing a shop misses is fogging correctly

so just pulled the intake and the block is cracked. this really puts a crimp in what i had planned for this upcomming weekend. i'm now looking at a new/remanufactured engine. i'm also starting to think that goin with an mpi might be the way to go if they'll bolt right up. of course all of this happens right after i get the thing paid off...i guess that's more $ to put towards a motor...

where are u located?
i get awsome deals on motors from jasper, i also have a los angles marine shop i get deals on

If you go MPI you going to need to ton of parts more, ECM, dizzy, fuel pumps, fuel coolers

eugene, or

oh ya---please lemme know what kind of deals...pm is fine. thanks-

email me, i can get you a motor in 5 days up there

When you winterized you just emptied the water but didnt add antifreeze? The only way to guarantee this will never happen again is to fill with 50/50 antifreeze.