Mercruiser 200MR, 230MR or 260MR water pump problems

[helix]

I bought a 1984 Ebbtide inboard boat from a guy last year. Unfortunately, the boat has been redone, and the engine has apparently had work as well so there isn't any sort of model or serial numbers on the engine or boat at all. The boat ran great all summer.

The original operator's manual was in the boat and the cover said it was for Mercruiser 200MR, 230MR and 260MR. The images in the manual match my engine exactly, but I'm not certain which one it is.

The engine does not seem to be drawing in water for cooling. I took the boat out yesterday and it seemed to be overheating. We pulled out immediately so as not to damage anything any further.

Today, I started taking hoses off the thermostat and water pump to see if there was any sort of blockage and there wasn't. I also started the engine with muffs on and checked the hoses again and they were completely dry. This is what makes me think there's something up with the water pump. I was concerned that I had some freeze damage (even though I winterized the system), but there isn't any water in the oil, which makes me think the block is OK.

I'm pretty good mechanically, and have worked on a couple of boat engines as well, but I'm not familiar with this model.

4 Questions:
1. What else can I do to confirm what the problem is?
2. Where's a good, reputable online place to buy rebuild kits (if necessary)?
3. I've noticed there are "upper" rebuild kits and "base" rebuild kits. How will I know which I would need?
4. What is a good, solid repair manual for my engine type?

Thanks in advance!

[Haut Medoc]

Welcome to iboats......
It sounds like you need a new impeller in the drive unit.....
There should be a ID tag back by the starter....
Not positive on the manual, Merc. manual #9 would be helpful, but there is a precorsor to that #3 I think.....
Don't waste money on a Clymer's or Seloc.....
You should be able to get an impeller kit here at iboats......
For your drive you need manual #6.......
http://www.boatfix.com/merc/Servmanl/6/6covr3.pdf
Courtesy of Don S.......

[Haut Medoc]

With the drive on the muffs, disconnect the hose that comes from the transom.....
Yours should go through the power steering cooler before it get to the engine....
Run for 20-30 seconds....
You should have good water flow, if not replace the impeller.....
You will most likely only need the impeller, but you won't know until you open it up......
Don't run the engine for more than 30 seconds or you will overheat your exhaust boots......

[helix]

OK. I've been diddling with this thing for over a month now while the season (at least here in the Midwest) is slowly ticking away.

I've replaced the impeller, gaskets and impeller housing with no results. I took everything apart again to make sure I put everything back exactly the way it was. Everything looked good. Tried again with no luck. I took everything apart again and flipped the impeller over (they come "straight" and take on a "curve" when you shove them into the housing) thinking it may be curved the wrong way. I got a little water then it quit. Took it apart again and the impeller was pretty chewed up. I took the old impeller (which is now better than the new impeller) and put it in to see what would happen and once again, didn't get anything.

Does anyone have any final words of wisdom before I take it to a repair shop and wait another month for it to be fixed???

Thanks in advance...

[Bond-o]

Ayuh,......

Make Sure there is a Clear path for the water to Enter the Impeller housing,......

Then Back-Flush the line from the Impeller housing to the T-Stat housing.......

You've got a Blockage in there,....... Somewhere..............

[Coors]

If you have a power steering cooler, check there, also.

[helix]

Thanks to Bond-o and imported_Coors for the tips on blockages!

I undid the hose leading from the PS cooler to the water pump and ran water "backwards" through it afew days ago. Got good flow out of the intakes on the outdrive, so I'm pretty sure there isn't any sort of blockage.

[Haut Medoc]

Then put a new impeller in.....
It does not matter if the vanes on the impeller arefacing wrong on a Gen 1, they will right themselves as soon as the the engine starts......
How does the impeller housing look?
Did you make sure that the key that locks the impeller in place was properly installed?......