New impeller fails
 

Hey guys,

A little help as i am def. not what you would call mechanically inclined!

Was only driving the fountain at about 3500 RPM's when i noticed the water temp slowly rising then as it hit 175 it skyrocketed. I turned off the engine

The mechanic changed the impeller for me, but when i inspected the previous one, it had all the vanes in tact so i doubt anything got stuck up in the cooling system.

Outdrives were clear of debris.

Now, because i live overseas we don't really have the gear heads ya'll got in the states. The mercury dealer told me there is a clog somewhere in the system and he's going to have to pull the engine out to find it.. that comes at a hefty price of $2000..yes 2k! I don't think this guys for real as he carries a bad reputation and is notorious for ripping people off.


So fellow boaters, is he telling me the truth that in fact he has to pull the motor? What could the problem be? The boat has one of those in-water flushing systems and has a ball valve which controls the water flow through the sterndrive or fresh water source. I have a gut feeling that the problem is lying there. He told me he checked that and it was fine. The motor was sucking fresh water from the alternative input but wouldn't take from the ear muffs.

Look forward to your reply

Thanks

Soooooo you went to a guy with an already bad reputation and and is known for ripping people off? Not sure I understand why you would do that. Even if mechanics are scarce where you are..... Just sayin'.....

Start with the obvious. Check the water pump again. If it was not lubed when installed, it could have been damaged when it was started the first time (I use dishwashing liquid). Was the wear plate replaced? Thermostat? Check your strainer (if you have one). Check your PS or oil coolers, and heat exchanger (if you have one). I would not EVER pay someone anywhere near that much without at least first looking at the basics...

I'd triple check (or temporarily eliminate) the fresh water flush attachment. I've seen the cheap ones lose suction just from the hose cap not tight. I think you'll find the problem there.

Also, if you've got the plastic housing sea pump, it's not uncommon to crack the hose nipple when tightening the clamps.

No way would I be paying to pull the motor for such a minor issue.

He should not have to pull the engine to find a clog in the system. I would start with what Biggus said and temporarily eliminate the Fresh water flush and go from there.

Unfortunately they are the only ones on the island that can do the work as they are the exclusive service center for mercruisers!

Sometimes the sea pump housing have flashings inside that kill the impeller quickly. Good idea to file those down. It has to be simple. Was your drive service lately? It could also be the water tube in the drive full of salt. Or that tube has collapsed. I say this because only happens when pulling water from drive and that is a common problem.

If it is pulling from the fresh water source, but not the outdrive, it may be what I've heard termed 'bravo fever'. Corrosion collapses the ends of the hose between the drive/bellhousing & transom, resulting in low flow. The plastic insert that holds the hose in place will break under the force of the corrosion, clogging the tubing.

Try this: unhook your water intake from the flush valve (hose between the transom and the valve), and put a set of tight fitting flush muffs on the outdrive. Put full water pressure against it, and you should get a full stream of water out the raw water hose. If not, that is where your clog is, and it is likely bravo fever. To change the hose does require removing the engine, but 2k sounds steep.

Also make sure they did not reverse the hoses when they reinstalled the pump. You would think they would test there work when they are done.

+1, I have done this before, and seen it done several times. They are not all the same either (top or bottom inlet). Take some time and learn how to change this yourself. It isn't fun, but a bad impeller can kill a weekend, vacation, or leave you stranded somewhere. It can be changed on the water. I always carry a spare, and I'm sure many others do also.

+2 Good Point