120 cracked block or ??

ohio river rat in KY

Petty Officer 2nd Class
Joined
Feb 10, 2010
Messages
104
1983 120 de winter rising tried firing up old gal on muffs, had to mess with the points had no fire, but while I was messing with that I seen brown kinda thick stuff in the hull under motor and was coming from where the starter is at from fly wheel cover. well got it running still a few drips but checked the oil pressure 40lb at idle checked the oil fine no water and even took off the oil filter was oil with no water in it, so what might this be ? were does a block mainly crack at cause this is the only thing I can think of but if it is wound it fill up the block with water? any help will be great
 

tazrig

Lieutenant Commander
Joined
Dec 20, 2012
Messages
1,752
Re: 120 cracked block or ??

Wondering if it's not a cracked block but rather a bad oil pan. Either rusted out and leaking or gasket let go. After you ran it did you check the oil level? If the oil level starts to go up on the dip stick then you might have a cracked block (water entering into motor and raising oil level) but it sounds like oil leaked into the bilge and then got contaminated with water based on you having run it and then even the oil in the filter looking good.
 

ohio river rat in KY

Petty Officer 2nd Class
Joined
Feb 10, 2010
Messages
104
Re: 120 cracked block or ??

oil level seems to be staying the same, just went out and checked it let it run back down in pan, but started it back up and let it run for 15 or 20mins temp was at 160 give it gas and let off a few times real quick it would leak more but cool to touch don't know if leaking more at higher rpm or if fly wheel is just sling it more and it purrs like a kitten. it not a milky color it looks like dieretta sorry for that comparizan ,and not much of a smell to it, when I winterized it I drained all water. spray wd-40 in all hoses,and every thing and leave all plugs out or lose that water pass through ,maybe this might help more?? water out of block is clean where its got the pit **** I losen it up while running it was warm clean water on it.
 

tazrig

Lieutenant Commander
Joined
Dec 20, 2012
Messages
1,752
Re: 120 cracked block or ??

can you get a phone under the engine where is leaking for some pics? Or at least get a hand mirror under there to see if the pan is all crusty and rusted? Could also be the rear crankshaft seal. If it's a steady drip you'll most likely need to pull the motor to either replace the pan or the seal or both. I know it's not what you wanted to hear but at least it doesn't sound like a cracked block! When you increase the RPM you're also increasing the oil pressure so you could well be increasing the amount of oil coming out and or "slinging" it farther from the flywheel because of the increased RPM's. Here is a link to help you track down the manual you'll need for the repair along with a bunch of other helpful info on Mercruisers:

http://forums.iboats.com/mercruiser...cellaneous-mercruiser-information-329915.html
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,465
Re: 120 cracked block or ??

oil level seems to be staying the same, just went out and checked it let it run back down in pan, but started it back up and let it run for 15 or 20mins temp was at 160 give it gas and let off a few times real quick it would leak more but cool to touch don't know if leaking more at higher rpm or if fly wheel is just sling it more and it purrs like a kitten. it not a milky color it looks like dieretta sorry for that comparizan ,and not much of a smell to it, when I winterized it I drained all water. spray wd-40 in all hoses,and every thing and leave all plugs out or lose that water pass through ,maybe this might help more?? water out of block is clean where its got the pit **** I losen it up while running it was warm clean water on it.

Ayuh,.... Pull the drive, 'n look in the bellows,....

Sounds like the drive is leakin' into it....
 

ohio river rat in KY

Petty Officer 2nd Class
Joined
Feb 10, 2010
Messages
104
Re: 120 cracked block or ??

this is while on muffs. should not leak in bellows on muffs right ? ok took off fly wheel cover and cleaned out the gunk best I could, fired it back up with out the cover let run 5mins or so seemed not to be leaking nothing now, wth could just setting all winter rain water or condentshion built up in the fly wheel area cause it has a cork seal around the bottom of plate, and it was leaking from the starter head hole and a place that looks like a loop d loop cut out on the side of the bell housing, might have missed a bullet hope so anyways, but sill like to hear more on this to see if its nothing or need to look more into it. thanks
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,092
Re: 120 cracked block or ??

Listen to Bondo, pull the drive to confirn its dry or has gear oil in it.
 

tazrig

Lieutenant Commander
Joined
Dec 20, 2012
Messages
1,752
Re: 120 cracked block or ??

I think what Bond-o was going for was to pull the drive and look to see if there was oil in the bellows. This would indicate the upper drive seal was leaking. Was the boat stored with the bow up or level? If it was stored level or a lot of oil leaked out of the upper drive seal than it could well have worked its way up the bellows and got slung around by the drive coupler (the piece the splined drive shaft goes into) making it look like it was coming from where you indicated when in fact it was coming from just the upper drive seal. I would pull the drive and check. You would have to do that anyway before you could pull the motor and if its just the seal than you did dodge the bullet. If the bellows is dry than you need to go back to a leaking oil pan, rear motor seal or possibly power steering hose leaking onto the motor and dripping down. With the age of your motor it could be any of the above. Also is the top half of your motor dry? Just want to make sure you're not leaking from somewhere else and dripping down to the starter area. Put the shift into forward, unscrew the 6 nuts, disconnect the tilt pistons, pull the drive and check for oil in the bellows. Easy enough to do and won't take long. Let us know what you find.
 

ohio river rat in KY

Petty Officer 2nd Class
Joined
Feb 10, 2010
Messages
104
Re: 120 cracked block or ??

pulled drive all looked good and clean. its got me. was stored with bow up the only thing I can think of is were I oiled it down for winter but never done this b-4. all oil levels are good. and after I took the cover off and cleaned it has not done it anymore but just don't under stand on the amount of what came out just guessing I would say a 1/4 of a quart or less it was brown thick gunk but. it just had to come from somewhere...idk yet
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: 120 cracked block or ??

May be excess grease from the drive yoke. It's slowly run down over winter and you're now seeing it. Do you put lots of grease on the yoke before putting the drive back on?

Chris......
 

ohio river rat in KY

Petty Officer 2nd Class
Joined
Feb 10, 2010
Messages
104
Re: 120 cracked block or ??

yep I sure do, think you might have hit the nail on the head achris never even thought of that. just had the drive out last summer for seals and restore and greased the fire out of it on install each time around 5 times in n out. thanks
 
Top