Head Gasket - Page 2

repirts · #11 08-05-2003, 10:42 PM

Decided to pull the power head open it up and see what is going on. Started tonight by removing all the cables and hoses from the head. Took notes and digital pics so that I can get it back together. Hope to have the head in my basement within the next week. I'll keep you posted.

repirts · #12 08-11-2003, 09:53 PM

My son and I pulled the powerhead yesterday. What a job! There were ten studs with nuts holding the powerhead on. Nine let go pretty easily but the tenth was another story. We were using a boom truck to pick up the head. That one stud was stuck firmly enough to lift the boat off the trailer. Eventually, with enough pounding and prying we got it moving a little. All of a sudden it let go and there was enough tension and stretch in the line to catapult it about 12 feet into the air. Luckily the lift line held and it didn't hit anything or anyone. When it let go both my son, Christian, and I hit the dirt. I can't remember jumping that far or that fast in a long time. Found myself under another boat about 10 feet away.

Brouhjt it home. Damn it's heavy. Pulled the cylinder heads tonight. Some of the cylinders had dark wear lines. They were not deep enough to feel. One had a line that was just noticable when you ran your nail over it. Problem or not? Compression on all cylinders is good.

Thanks
Repirts (Steve)

Roland Rodriguez · #13 08-14-2003, 07:29 PM

Remember to have a torch nearby. heating the bolts will expand the aluminum and free them.
Start in sections. I dont think its in the cylinder/piston section as you have good compression. Take the carbs off as a whole unit so its not a mess latter. Take the intake off and inspect the reed valves. Last resort is spliting the engine and inspecting the crank and bearings both upper and lower. It's a relatively easy pump, driven by crankcase pressure. Email me directly at Rolrodjr@aol.com I've been there buddy....

repirts · #14 08-14-2003, 09:38 PM

Hi Roland,

I agree that the top of the engine seems to be Ok.
Flipped it over tonight and started to dig my way to the crankcase. Took one look and came to the same conclusion you did- pull carbs off as unit to preserve as many settings as possible.

While I was staring at it to figure out the best way of getting it apart, I noticed the the oil line from the pump was just barely attached. It fell off as soon as I touched it. Glad it did it now, not when it was running! As I'm reassembling I'm going to inspect everything and replace as many hose as possible. Cheap good insurance.

repirts · #15 08-17-2003, 07:39 PM

Pulled the intake manifold. Reeds look like new. Nothing obvious wrong but something WAS WRONG the last time it ran so I'm going to open the crankcase and check out the bearings etc. What should I be looking for?

repirts · #16 08-18-2003, 10:40 PM

Now that I have the intake housing off I can see the ends of the cranks and the counter weights. They have a light coating of rust. I'm new to 2 cycles and expected the cranks etc to be coated with oil. They look dry to me but I know the engine was getting oil because the cylinders are coated. Could the blown head gasket have allowed water into the crankcase and caused the rust? I'm going to open the crankcase sometime this week. What should I be looking for?

thanks

gss036 · #17 09-07-2003, 12:41 AM

Just read throught he post the 1st time, what did you end up with? I am thinking a rod bearing?
Not a mechanic but curious. I run a 1989 200hp Mercury and change the head gaskets about every 3rd year since I just run saltwater. Seems to be about the right time as I have never had one leaking.

repirts · #18 09-07-2003, 09:41 PM

Exactly. Lower rod bearing rusted to h*ll but thankfully the crank journal is OK. Should be Ok replacing the bearing. On the piston end of the rod it was so rusted that you could barely move it. That end will need to be changed too. I'm lucky that it didn't throw the rod or bend the crankshaft. I'll be buying the parts this week and starting to put it back together. Maybe I'll get it in the water just in time to pull it back out but I will have a least gotten it in the water!

gss036 · #19 09-09-2003, 11:48 PM

Good luck on your project, most people would not attempt the job. I know I wouldn't.

Jon G · #20 09-10-2003, 07:36 PM

Good job Steve. I just got rid of my 1998 merc 115 because of a rod knock. No one down here would fix it every one wanted to replace the power head($4000) so I ended up selling the Merc for $800 as is with all the controls and buying a new engine (on paper). I didn't want to tear that thing that far apart(I'm not a Merc fan anyway) so my hats off to you for a good save! I Hope it runs well when you get it back together [img]images/icons/grin.gif[/img]