Milky Spark Plug

[csvencer]

1982 Classic 50 4 cylinder started idling funny last time out and don't have full power, lost some oomph to get up on plane. Got home and pulled the plugs (was thinking a fouled one) and found the top to be a little milky. Cleaned them all up, ran it on muffs again for a bit and found the top one dirty again. Pics below. This is from just running a min or two, when I first pulled them it was much milkier. Second pic is #2 cylinder for comparison. Thinking head gasket but not sure. Any thoughts? All help is greatly appreciated.

Thanks.

EDIT - Also checked compression and found it to be fine.

 

[CHIEF TERRY]

Re: Milky Spark Plug

Maybe you are rite , next do a compression test and maybe connect a vacuum gauge , a steady reading is what you are looking for
you say milky ? Is it dry ?if it is dry its from water ,if wet its from oil !!

 

[csvencer]

Re: Milky Spark Plug

Compression was good. Milk is wet. Not sure what that means.

-Svence

 

[chum1]

Re: Milky Spark Plug

Those plugs are to clean, looks like water. More then likely its the side exhaust cover gasket or the lower crank seals that cause the leaks, fairly easy chore once the powerhead is off and all the exh. cover bolts come off without snapping.

 

[csvencer]

Re: Milky Spark Plug

Are we talking #10, #17, or #30?

http://www.boats.net/parts/search/M... AND UP/END CAPS AND EXHAUST COVER/parts.html

The plugs are clean because I wiped them down to see if they would come back wet or not, then ran it again for a min or two.

-Svence

 

[CharlieB]

Re: Milky Spark Plug

Items 28 and 29

The exhaust cover and inner plate sandwich cooling water for the exhaust, a leaking gasket here can allow water to spray water back in the exhaust port.

 

[chum1]

Re: Milky Spark Plug

We are talking #30 #28 and #21, all #10 does is hold the water in from spilling out the back as the cylinders are fully enclosed except for the spark plug holes.

Milk = water on the sparkplugs, it will still run for a while but major problems later.

part #29 and #31 will usually be stuck together along with both gaskets once the bolts are out.

If you get consistent chocolate milkshake plugs they need to be dried up, merc's don't like shakes.

 

[csvencer]

Re: Milky Spark Plug

Can I do the side exhaust gaskets without removing the power head from the mid section? Understand #21 will require removal but would like to limit that if I can.

Thanks.

-Svence

 

[chum1]

Re: Milky Spark Plug

It could probably be done but getting the lower bolts out with the lower cover on may be difficult, it is on the earlier 70's engine's anyway.

Also if the bolts snap :facepalm: they are much easier to drill out with the powerhead on the bench.

Starting a project like this i always try to fix the problem once, then hopefully forget about it.

 

[CharlieB]

Re: Milky Spark Plug

LOTs of PB Blaster, time, patience, a big hammer. Actually not, a small ball peen is enough.

Soak them, smack each one on the head to get its attention and let it know who's Boss. Actually the shock helps crack loose corrosion and lets the PB Blaster penetrate deeper.

Heat any stuborn bolt heads smoking hot, let them cool and soak them again overnight. Do not attempt to turn them while hot.

Rock each bolt slightly out/in to assist breaking up the corrosion and aide the PB Blaster to soak in.

 

[csvencer]

Re: Milky Spark Plug

So did a quick look this morning. Looks like there is no way to do the bottom bolts without pulling the head. How big of a job is it to pull? Any heads up tips I need before pulling it? And since it looks like it will be coming off, anything else I need to replace while it is?

Thanks.

Svence

 

[chum1]

Re: Milky Spark Plug

First thing, beg, borrow, buy or steal a flywheel puller/ lift ring, they can be found here:

http://www.amazon.com/Mercury-Marin...9MN2/ref=sr_1_2?ie=UTF8&qid=1312153933&sr=8-2

This way you can lift the powerhead straight up with less grief and straight down without damaging gaskets.

download a merc manual (not seloc) for your engine and read through it.

With powerhead on table or bench you can easily get at lower crankshaft cap for seal replacement, you may have to rig up puller to pull it off, these seals may be also causing your problems. Once off you can now replace the driveshaft seal too

Take your time and do it right with the correct parts and gaskets your passengers will like it.

 

[csvencer]

Re: Milky Spark Plug

Well I already have the flywheel puller and lift ring as well as the Merc Manual, so I guess I am starting on the right foot! Going to start disconnecting everything (for once I am pissed I got electric start and remote controls...) this week. Once I get it off I will start ordering gaskets and seals.

-Svence