too hot??

Just back from holidays and my engine was acting up a bit. We had the boat really weighted down last Sunday and ran it straight for about 5 hours. It started loosing power, if I was towing at 21mph, it would slow down all of a sudden and I couldn't keep the speed going. We let it sit for about 3 hours and it was working fine again. It's never done that before. Were we working it too hard?

Half of the people in the boat could board the other half were first timers. I'd empty the internal ballast for the first timers and refill for the rest of us. For the newbies, I hit it, stop and turn around, 10-15 times. Is this too hard on the engine with too much weight?

Weight wise, there were 10 (6 adults, 4 kids) in the boat. Two 350 pound sacks, one in the bow and one in the back that we didn't empty. The KGB we would empty for the newbies.

Just a case of vapour lock or something more serious?

Did you add any gas to the tank during the three hours the boat sat? Running straight for five hours makes me wonder if maybe you gas wasn't getting low and might have a bit of water in the tank?

If it recovers after sitting then I would expect a fuel problem. I would start by changing the fuel filter. If the fuel filter is a water separating type then I would pay close attention to the contents of the filter when you change it. Drain it out into a glass jar if possible and inspect it.

Rod

check to make sure you don't have a cracked insulator on one of your spark plugs. Mine did the same and that was it. Also your fuel pump could be going out, but that is rare with the newer engines

Have you looked at your impeller? If you were overheating, perhaps due to a bad impeller, the engine could be preventing high revs in an attempt to save the engine.

Happened to a friend this weekend, we looked at the impeller and...no fins left.

Whit, didn't had any gas during those hours. It was done to about a 1/4 tank by then.

Chris, I've never changed the impeller. Where is it located? Is it hard to change?

01 MC X-10

The impellers are real easy in the direct drives and not too bad in the V-s

On the V drives the impeller will be on the stern side of the engine. There will be a flat face plate with probably 4 screws holding it on. Undo the screws take the plate off and the impeller will be sitting right there. You should have rubber "fins" (like a paddle wheel) all around it. They may have been completely worn away.

To get it out take a pair of pliers and it should just slide out. A new one should be maybe 30 or 35 at the dealer.

Hope that is your problem...

Pat,

sorry to hear about the delema. . . be sure to call me and let me know the outcome!!??

I'm in agreemtent with the impeller thought, did you notice if the engine was running a lot warmer than normal??

The water temp gauge isn't reading any higher than it normally does. So I don't think it's overheating or anything. I was thinking my problem may have just been vapor lock or something. I don't know if the impeller has ever been changed so I'll try and take a look in the next couple of days here.

Stern side of the engine. so Closest to the back seat right? as the front of the engine is facing the back of the boat in a V-drive.

Toe side, it took me a second. Hey I rode in the Hyperlite contest on the weekend. Got third, finally figured out the 180's both on the toe and the heel.

Did you make your trip out east yet?

Change your impeller! Even if its not your problem you should change them every year IMO. It is bad mojo if it fails while you are using your boat.

(Message edited by ralph on August 24, 2004)

Impeller in v-drive will be on the back of the boat side.

In a d-drive it is in the front (right by the pylon.

Ok so what am I looking for? There is a flat triangular piece of metal attached to the top of the engine with two hoses going in (one on each side). Is that what I'm looking for?

Tried to find it in my manual last night, can't find the manual though.

follow the hose that comes from your through hull fitting (raw water pickup) that will lead you directly to your impeller housing.

Anyone have any pictures of it?

The water pump is driven by a belt on what would normally be considered the "front" of the engine. On a V-drive the engine faces backward so the belts are to the back.

The pump can be easily identified: it has two big hoses attached to it. Find the belt, follow its path till it goes around a bronze casting thing with a couple big hoses attached to it. That's the pump. The pump comes apart, hopefully easily. Most of the pumps used in these boats have a flat plate on the back, held on with 4 to 6 screws. Remove the screws and the plate comes off. The impeller slides out the back (with the help of a pair of pliers).

NOTE: Before you remove the old impeller, note the direction the pump turns! Crank the starter and watch the pulley turn! You will need to know this when you put the pump back together!

If you are lucky there will be enough room to work so that you don't have to remove the pump in order to get the plate off. Replacing the impeller was a 5 minute job on my old direct drive boat. I haven't tried it yet on my new V-drive.

There is a bit of a trick to get the new impeller in. First, lubricate it with some (I usually use a white lithium grease, but dish soap might work just as well). As you start the new impeller onto the shaft rotate it the directionn it will eventually be turning. You need to bend the vanes of the pump in order to get them into the housing.

Once the impeller start into the housing it will engage the "key" and you won't be able to turn it anymore. Push it in as far as it will go, then put the back plate back on. It is also a really good idea to replace the gasket/seal for the backplate as well.

OK took the back plate off. Didn't take the impeller out but it looks pretty good. Lots of rubber and it's bent about a 1/4 inch on all of the blades. I didn't take it out, I gave it a little tug and it's in there pretty good. Should I just leave her in there or take it out to inspect it? I don't have a new one yet, and I don't want to damage the existing one.

LEave it in...but, get a new one as soon as possible. If you think it has been in there for over a year, it should be replaced. When they come apart while you are on the water, bad things happen. Don't risk it. In fact, get two impellers, that way you can carry a spare.