Afraid of the water

[bigskiohio]

Re: Afraid of the water

just look at the choke. takes a minute while running .

 

[Cam Powell]

Re: Afraid of the water

I would check your compression as I have seen motors run well with muffs and not in the water. It is backpressure. I hope your motors not tired but it sounds like it. good luck. Cam

 

[bkhdmh]

Re: Afraid of the water

So I filled the bilge to about half full to make sure there are no random sensors that would keep the engine from starting. Well there aren't and it still started fine.

This afternoon I came home and got them boat running. TO the point where it would take about a second or less to start when the key was turned then in order to attempt to duplicate the issues I am having when the boat is in the water I stuck my hose into one side of the exhaust tubes coming out of the back of the boat that look like hoses that have been heated and pinched shut (don't know the technical terms), I also pinched the opposite side shut with a pair of vise grips. I did this to try and simulate the boat being submerged. And the boat would not start. It took about a minute for the boat to start.

When I purchased the boat it had a cracked block and head due to incorrect winterization.

I am thinking there is a good likelihood that he also cracked the exhaust manifolds and water is getting somewhere bad.

What tests can I do to verify this?

To recap:

The boat runs great in the driveway and hooked to muffs but as soon as it is submerged it will not start. If it does it takes about 10-20 to get it to start but then runs fine. The only time I have gotten it started on the water was in salt water. Not sure how much difference there is between the salt and fresh water when it comes to possible water leaks.

 

[Maclin]

Re: Afraid of the water

compression numbers?

Putting a running hose into an exhaust pipe is a good way to induce hydrolock by water finding it's way all the way up to an open exhaust valve and on into the cylinder. The fact that the engine turned over at all after that means it did not happen, but watch what you are doing.

compression numbers?

Do you have thru-hull exhaust? Your description of the exhaust tubes at the back of the boat is confusing. On a Volvo leg the exhaust comes out the port just above the prop.

I get the feeling you think it is electrical, your salt water comment would lean towards ruling that out because salt water is a much better conductor than fresh water and the liklihood of a short would be far greater in salt water.

compression numbers?

Submerging the leg in a large tub full of water will simulate the lake much better than a runnning hose. I found a large tote that works good for me when I need to do that.

compression numbers?
what do the spark plugs look like?
results of other suggested tests?

 

[EddiePetty]

Re: Afraid of the water

So I .....stuck my hose into one side of the exhaust tubes coming out of the back of the boat ...I also pinched the opposite side shut with a pair of vise grips. I did this to try and simulate the boat being submerged. And the boat would not start. It took about a minute for the boat to start.

When I purchased the boat it had a cracked block and head due to incorrect winterization.

I am thinking there is a good likelihood that he also cracked the exhaust manifolds and water is getting somewhere bad.

What tests can I do to verify this?

...now I beleive you're getting somewhere!!!

Your garden hose simulation, combined with the fact that the head and block have been changed out, leads me to believe that you either have an incorrect gasket in the riser and/or a crack in the exhaust manifold.

I am certain that Don S. can straighten you out on the correct gasket(s) and manifold tests.

FWIW....Ed in 'ol Virginny

 

[myoldboat2]

Re: Afraid of the water

Have you considered the angle of the boat on the trailer in the driveway vs. the angle when in the water? If your carb is dumping fuel that angle could matter.

I think you should do the tests that have been recommended. In order or easiness...


- look at the choke throttle plate with the engine cold, warm, fully warmed

- carefully check for the carb dumping fuel while trying to start, running and after shutdown

- look at the spark plugs and report their condition

- run it in the driveway with the sterndrive in a large tub of water filled to the normal water line (you can probably see it on the drive) -- can you vary the angle by parking on different spots on the driveway?

- do a compression test

- if none of the above reveal the problem, consider more voltage measurements


the first four tests can be done in less than an hour (probably a lot less). the compression test doesn't take long, either.

if you do some of these tests and report back here, the experts here should be able to help you.

 

[kevman]

Re: Afraid of the water

Hello,

I am not an expert on boats at all but I had a similar experience with a car. It would start up well but then when I would shut it off the cylinders would fill up with water. Then I would have to crank it forever to get the water out of the cylinders. Maybe the suggestion already mentioned(wrong gasket or cracked manifolds) is the case. Check your oil to see if its milky because if water is leaking in, it will get into the oil. Again, I am not a mechanic but its just a suggestion.

Kevin

 

[Blk-n-Blu]

Re: Afraid of the water

Just a thought, Have you checked for a broken exhaust flapper?

 

[bkhdmh]

Re: Afraid of the water

Ok so the boat's engine builders finally swallowed their pride and did a compression test. 1,2,4,7,8 read 160; 3 reads 150; 5 reads 45; 6 reads 100.

The boat has not been burning oil (no white smoke) so I am would think the bottom half of the engine is good. I loosened the rocker arms for 5 and 6 and raised 5 to 90 and 6 to 120. I think I need to rebuild my heads and this should fix the problem. Going to winterize it for now until I have time to tear the heads apart.

When I am rebuilding the heads I will change out the lifters as well.

Its either that or replace the entire engine.

Who knows.


Thanks for all the advice along the way.

Brian