Help regarding 1987 21z

[Charles]

I have a 1987 21z with the side exhaust I had a new engine installed 2002 350 vortec. I have had a few problems since I put it in. I had a mercury marine mechanic look at it this time. The last problem I returned the boat and engine together to the engine shop in Pompano Beach, FL Daddyo's Marine Enginee from Jacksonville, FL. It was miss fireing bad (timing) So I decided the next time before the warranty expired to send it to a local dealer. After reveiwing they advised 2 dead cells on one side took motor out sent back to Pompano and then they looked at it and advised there was water in two cylinders and this was caused because water went in the exhaust....I advised that I do not have flappers from the back....Question??? could water get in from the exhaust on the sides, does any one have any thoughts..... I feel he is trying to get out of the warranty......

[BUIZILLA]

1) how did water get in only 2 cylinders and not all 4?
2) is it fresh or salt water in those 2 cylinders?
3) are the 2 offended cylinders adjacent?

J

[EricG]

I don't really have an explanation of whether or not the water could get in Via the exhaust, but, I have a couple of observations regarding the Z21's exhaust:

First, the side exits do have flappers in them, if you look in with a flashlight, you can see them...If your boat is anything like mine, the flappers aren't exactly in top shape any more. I don't know where you could get replacements...

Second, maybe one of the others here could talk about how much of a problem reversion could be in a setup like ours. For those not familiar with a Z21 exhaust, the pipe runs off the riser straight back, turns 90 degrees when it meets the transom, and runs litterally 3+ feet at a down angle to the side exit. I would think you've have to have a heck of a lot of wave pressure to push water up that pipe into the motor....but I'm just guessing.

Anyway, I hope that helps a little...

EG

[jdsdls]

I had an 88 Z-21 with side exhaust. The orginal flappers are in the tips of the exhaust, if there are none you need to but a set in what happens is as you come off plan and the motor slows down the water goes right in the side exhaust and into the motor. I lost a motor this way.

[Greg Maier]

Have the manifolds been checked? It sounds like they could be leaking into your engine. It could be bad gaskets or an actual hole in the water jacket.