Cleaning water passages Evinrude E150EXERV

[woodycooper]

Once I removed the head I found most of the smaller passages plugged with salt. Problem is, the block has more passages than the head does. Where the two meet you can see a salt/corrosion mark on the head. Why is this? Perhaps this head fits a few different blocks or vice versa? Anyhow the small passages were all nearly blocked but water does flow from the thermostat housing to the bottom of the head and out. PIctures for reference, I highlighted where the block passage dead ends into the head.

 

[oldboatfixerupper]

I would try lime-a-way a drill bit and some guitar strings and a case of beer.

 

[woodycooper]

I would try lime-a-way a drill bit and some guitar strings and a case of beer.

Maybe I didn't explain it right. The block has a water passage that the head does not. What I've highlighted is corrosion on the surface of the head where the passage in the head dead-ends into the head. No amount of flushing will change that, I was just wondering why that is.

 

[saltchuckmatt]

Maybe I didn't explain it right. The block has a water passage that the head does not. What I've highlighted is corrosion on the surface of the head where the passage in the head dead-ends into the head. No amount of flushing will change that, I was just wondering why that is.

Is there a part number on your head? You could check to make sure it is correct for your engine.

Correct part number is

0338082​

 

[oldboatfixerupper]

Do this part look more accurate? Is it over heating?

 

[woodycooper]

Is there a part number on your head? You could check to make sure it is correct for your engine.

Correct part number is

0338082​

I don't think it's too likely that I've had the incorrect heads installed on this motor before I bought it with 153 hours on it. I can go back and check the part numbers but I'd be willing to bet those heads fit on any V6 carbeurated Evinrude. Whatever the case, they've worked fine until what appears to be a leaking head O-ring occurred and when I removed the heads to clean them I noticed this anomoly.

 

[woodycooper]

Do this part look more accurate? Is it over heating?

The one in your attachment looks like mine. It appears to have the same corrosion marks, but do I see some small passages in there or was the aluminum corroded away to look like a small hole? I've poked them with a center punch and a razor blade and looks like there's no passage that I can see. The main symptom here is overheating. Thermostats and sensors and water pump all replaced so when the problem persisted I decided to clean the heads and replace the O-rings and thermostat seals. A bunch of sand and salt and other stuff came off/out. Overheating never occurred before so I'm thinking blown head gasket (o-ring) as I've replaced everything else and water flows (at idle ) through the thermostats.

 

[woodycooper]

Once I removed the head I found most of the smaller passages plugged with salt. Problem is, the block has more passages than the head does. Where the two meet you can see a salt/corrosion mark on the head. Why is this? Perhaps this head fits a few different blocks or vice versa? Anyhow the small passages were all nearly blocked but water does flow from the thermostat housing to the bottom of the head and out. PIctures for reference, I highlighted where the block passage dead ends into the head.

View attachment 371401

I did a little research and this head sold on eBay looks identical to mine, right down to the witness marks from the dead end tubes. I'm not going to worry about it. Here's the head I found: https://www.ebay.com/itm/294389380129