Recent content by Lou C

Brush on Rustoleum primer followed by their paint.

Also Next time you take off the manifolds, you'll see rust in the exhaust ports in the cyl head if the water from either a leak or condensation is getting into the cylinders and you'll know which cylinders were affected. When I had water in the cylinders, it wasn't much at first but got to the...

Not necessarily. Is there any water in the motor oil? Another test is to run the motor for about a half hr and then pull the plugs again. Crank the engine & see if any water comes out of the cylinders. If you start with exhaust that’s not leaking (cause you verified by testing it first) there...

The pic of the 3 plugs the one on the left and the middle def look rusty. BTW use Delco Marine plugs instead, they are more rust resistant and do not seize in the threads.

From the left the first one & the 6th one definitely look like the metal shell is rusty. Which cyls did they come out of?

I see what looks like a seperate feed for the elbow back there on the side and is there a hose that goes from the HE to the exhaust manifold? I think so….

Yep it’s hard to know but if you can test the way I described that’s about as good as you can get. You have an EFI engine that’s port injection, right? I’m wondering if you have some lean (clogged) injectors and some that might be rich looking at the plugs. When I had water in a cyl from a blown...

Is the exhaust manifold on the closed cooling circuit? If not then it has to be drained, and even if it is, the elbow should be drained as these are always raw water cooled. That and the raw water intake hose running from the transom mount to the heat exchanger. You can disconnect the feed hose...

If you start it that way, they won't get cooling as they should, that can overheat the exhaust rubber hoses and flappers. I don't think that will do anything to solving your concern. I bet your exhaust system is only at about 90-100* under those conditions, idle, cool day, cold manifolds...

If it were a leaky intake manifold, that would put water right in the oil since it would leak into the cam valley, I doubt that it would put water in the cylinders Here's what you might do If you can remove/install the manifolds and elbows as a unit, all assembled, you can remove the ones you...

did the ones that look steam cleaned come from the center cylinders?

I wonder if you can convert yours to the dry joint if/when you need to replace the manifolds? If so I would. Much better design!

If you just have it idling on the water hose on a cool day, the exhaust might not even get up to 100*F, so a small amount of water can be condensation in the exhaust, just like what comes out of your vehicle tail pipe on short trips that don't heat up the exhaust enough to evaporate out the...

You know that some gaskets get gasket sealer but some do not. Which did gaskets you use? I know Volvo has specific instructions on what to use with their gaskets, what does Merc say? Also, as a general thing you should always measure the flatness of the sealing surfaces with a straight edge and...

What did the sealing surfaces look like on the manifolds and elbows? Any pitting, loss of material due to corrosion, etc? That's what often starts a wet joint design leaking, the sealing surfaces get deteriorated from salt water corrosion. They should look like this: this is the OMC/Volvo...