Re; Broke spark plug

[kash35]

I have the same problem. after replacing the water pump, my mechanic couldn't start the boat. He checked the plugs and one broke off. He can't remove it without removing everything and get inside the engine. He's estimating about $1500. Just got the the boat about three months ago and have had to replace the water pump, throttle cable and carb. Now this. Any suggestions.

 

[Bondo]

Now this. Any suggestions.

Ayuh,..... Welcome Aboard,...... There were quite a few suggestions in the 12 year old thread ya posted in,......

Lets start fresh,........ What motor/ drive,..?? what vintage,..??

Are ya Handy,..?? do ya have a garage fulla tools,..??

 

[Searay205]

Your mechanic in idiot. get a vacuum and gently break away the ceramic. I suggest you get new plug and practice on work bench first see how it breaks. Once ceramic out get easy out insert in center and back out. You do not want ceramic in your cylinder. I could probably get a socket to still fit on that one. Get a snap-on socket, not some chinese sloppy tolerance sheet. it may back it right out. little liquid wrench and heat wouldn't hurt either before you attempt backing out

 

[nola mike]

Try something like these:

https://www.amazon.com/dp/B083FSBFQ6?ref=ppx_pop_mob_ap_share

 

[kash35]

Thanks for the suggestions. The motor is a 4.3L GL SX-A drive unit. I'll try knocking the ceramic out myself. Mechanic said he tried knocking it out but it's too hard. At this time, I'm starting to doubt what he's telling me anymore. Will let you know.

 

[Bt Doctur]

Pulling a head is not that hard and if you get ceramic in the cylinder your going to pull the head anyway,

 

[Lou C]

I would not knock out the ceramic unless you are prepared to pull the intake and cyl head. Soak that in a combo of all the best penetrating oils (Free All, Freeze off Aero Kroil etc). Let sit for several days. When they evaporate try heating the cast iron around the remains of the plug very carefully (all those oils are flammable!)...Use a very good six point plug socket. Believe it or not gentle use of an impact gun may be better that steady pressure with a breaker bar. I got all of the cyl head bolts out of my 4.3 using my De Walt 1/2” drive impact gun. 15+ years of raw water cooling in salt water no way they would come out by hand even with a long 1/2” drive ratchet .. did not break one bolt using the impact gun. That or pull the head and take to a machine shop. In that case I’d remove both and have them gone thru...

 

[Lou C]

PS salt water boat? The only way you get that much rust is a constant drip from an exhaust manifold hose or drain. Make sure to repair the source of the leak. I had a small water drip from my OMC batwings drain plug one year and it rusted up the terminals on the starter solenoid in no time.

 

[kash35]

I would not knock out the ceramic unless you are prepared to pull the intake and cyl head. Soak that in a combo of all the best penetrating oils (Free All, Freeze off Aero Kroil etc). Let sit for several days. When they evaporate try heating the cast iron around the remains of the plug very carefully (all those oils are flammable!)...Use a very good six point plug socket. Believe it or not gentle use of an impact gun may be better that steady pressure with a breaker bar. I got all of the cyl head bolts out of my 4.3 using my De Walt 1/2” drive impact gun. 15+ years of raw water cooling in salt water no way they would come out by hand even with a long 1/2” drive ratchet .. did not break one bolt using the impact gun. That or pull the head and take to a machine shop. In that case I’d remove both and have them gone thru...

So I had to remove the head and the machine shop removed the plug in five minutes. After installing everything back, the engine started and everything worked. I took the boat on the water and the engine overheated. Brought it back home and checked the raw water pump and Impeller was in pieces. I had to pull out the broken impeller pieces from all of the water inlets. Changed the thermostat and everything is running well.
The previous mechanic totally screwed me. I believe the reason he couldn't start the engine because the kill switch was not engaged. I know this because it happened to me. Boat was cranking but not turning on. Luckily, I checked the switch and clicked it in properly and boat started right up. He never checked it and went straight to the plugs and broke one of them. So, I guess, always check the basic stuff.
Anyway, I'm happy the boat is running and thanks everyone for the suggestions.

 

[Baylinerchuck]

I love a story with a happy ending.

 

[Lou C]

Yep looks like you found the right mechanic!

 

[kash35]

I love a story with a happy ending.

Yup. It's definitely a very happy ending.

 

[louc]

PS looking at your pix it appears that the rust was from a leaky exhaust manifold to elbow gasket, are you replacing these parts?
here's what they look when new....leaks from there can leak into cyls via an open exhaust valve but as you found out they can also rust up spark plugs!

 

[kash35]

PS looking at your pix it appears that the rust was from a leaky exhaust manifold to elbow gasket, are you replacing these parts?
here's what they look when new....leaks from there can leak into cyls via an open exhaust valve but as you found out they can also rust up spark plugs!

I didn't change that gasket but I definitely will now. Should be pretty easy. Thanks for the tip.

 

[Lou C]

That joint between the elbow and the manifold is something you have to monitor, if you see rust trails on the outside it is time to drain the manifold and inspect the water ports for rust and chunks of cast iron coming off and pitting on the sealing surfaces. I installed these 3 seasons ago (same exhaust you have just on an OMC) and the joints still look great. As soon as I see any sign of leaking it comes off though. In salt water we usually replace the exhaust between 5-7 years of use. I'll see how they look after 5 seasons.
Any leak of salt water causes a lot of damage, quickly!

 

[kash35]

That joint between the elbow and the manifold is something you have to monitor, if you see rust trails on the outside it is time to drain the manifold and inspect the water ports for rust and chunks of cast iron coming off and pitting on the sealing surfaces. I installed these 3 seasons ago (same exhaust you have just on an OMC) and the joints still look great. As soon as I see any sign of leaking it comes off though. In salt water we usually replace the exhaust between 5-7 years of use. I'll see how they look after 5 seasons.
Any leak of salt water causes a lot of damage, quickly!

View attachment 327143

So I ran the boat on the lake for two hours after changing the thermostat and removing the broken impeller pieces, everything was fine. No overheating.
I started the boat today with muffs on and no water was being pulled in. Very strange. I'll check the hoses again tomorrow and maybe check the impeller.

 

[Lou C]

Make sure your muffs fit well. Some are made out of rubber that’s too stiff to confirm to the lower gear housing. And then not enough water gets sucked up to the impeller. The best ones I’ve used are the Merc/Quicksilver round ones with the metal rod clamp.

 

[Baylinerchuck]

That is strange. How do you know that no water was being pulled in. If that is the case, your impeller will be smoked.

 

[Lou C]

with an engine mounted impeller, if the water line drained of water when the boat was pulled out, unless your muffs fit really well you can have this problem. Not as common on an Alpha since the raw water impeller is right in the lower gear housing and the water doesn't have to travel far before the impeller can pull it in. On a Volvo, or Bravo system the water has to travel up 1.5' and approx 3-4' forward to reach the impeller. I used to use the Tempo style muffs dual inlet and the last pair of them I used (right after my top end overhaul) it seemed that the rubber was stiffer and I could not get my Cobra to prime easily as I had in the past. The Cobra is a little different from the Alpha in that the impeller is in the upper gear housing (very easy to replace) but water has to travel about 1.5' up to reach it. I switched to the Merc/Quicksilver round ones with the metal rod clamp and it was 100% better. The Merc muffs are softer rubber that conforms to the shape of the lower unit better and the clamp holds it tight. Well worth the extra $$
After starting the engine you should see water getting exhausted under the transom mount within seconds. If not then its not pulling in water and remember impellers can't move air only water.

Dropbox

www.dropbox.com

notice how much water is exiting the transom mount in the vid.

 

[Rick Stephens]

If not then its not pulling in water and remember impellers can't move air only water.

One should not even use the word 'pull' when referring to a Mercruiser leg mounted impeller. That pump can't 'pull' water even a quarter of an inch. The pump is vented to allow air to escape (which also means it makes ZERO suction!). This makes it self priming, but only when completely submerged.

Rick