zog02

The engine has approx 300 hours on it. I am inclined to believe those of you that think it is an exhaust gasket problem. I can't imagine that something would have broken over the winter while it was not running. Hopefully I will have some time this weekend to do a little more investigating. Thank you very much for all the replies.

boatn70

got corsa/gil silent choice, those things have bushing that wear also...then begin the ticking sound.

zog02

I just went out and put a couple hours of work in doing some investigating. I loosened the starboard manifold then retightened it. I started the motor and the ticking sound was still there. I ran my hand on the underside of the manifold and I beleive I can feel a slight bit of hot air coming out around the number 4 cylinder. I pulled all the wires off at the distributor cap one at a time. The motor stumble slightly with every wire I pull off. I believe all the cylinders are working properly. When I pull the wire that goes to the number 4 cylinder off the ticking sound goes away. I switched the spark plugs around and that makes no difference.

My thinking is that there is an exhaust leak around the number 4 cylinder. (Where the manifold attaches to the head) When I pull the wire off that would mean there is no explosion in that cylinder and therefore no sound leaving through the exhaust leak at the manifold. Anyone have any other ideas....I really appreciate all the help so far.

Lmarth

Good troubleshooting on your part. The dillema for all of us is that we have to rely on what the originator tells us. My understanding is that there was no ticking noise until you removed the exhaust manifold. Now it ticks and appears to be at #4. Did you replace that gasket again? If not, I'd suggest doing so. It's easy to gouge the gasket surface as you wrestle with the manifold. You may have created a leakage path to #4. Anything can happen. If you do change the gasket again, I'd take a good lookat the manifold surface around #4. Just tryin to help. Let us know how you make out.

zog02

That is correct....there was no ticking noise before I removed the exhaust manifolds. I have not removed the manifold and replaced the gasket since I heard the sound. I loosened the manifold and retightened it again this morning. I remember wrestling with that gasket and manifold. I am assuming that like you said I may have made a gouge in it. I am thinking of pulling it off and replacing the gasket. I am just happy that it seems to be nothing internal. It is hard for me to imgaine that a small leak will make a sound like that but I have no other expalation for it.

Lmarth

They will tick and it will be sharp tick. When I was a teenager, My dad had a Ford where, by design, there was no gasket between the head and exhaust manifold. It would tick every once in a while to the point where there was a wrench under the seat to tighten it. If Ford had put 'French Locks' on it like a lot of stock Chevies, it wouldn't have kept backing out. Lots of things will tick. Lifters is one of them. If it's piston slap, the noise usually goes away when the motor gets hot. GM has had a huge problem with piston slap a couple of years ago. Piston slap usually doesn't develop. You'll have it with a new motor or a freshly rebuilt motor where the piston skirt/cylinder bore spacing is excessive.

zog02

Lmarth, you are the big winner. It was an exhaust leak. I pulled the riser off and took the manifold off. I found the gasket had a big crimp in it right around the bottom side the number 4 cylinder. I guess in all the wrestling with the manifold the gasket got bent somehow. I got a new gasket and re-assembled everything. When I turned the key it made the most beautiful sound. No ticking, no nothing. It purred like a kitten. I really appreciate all the help you guys have given me. I suppose I would have found it eventually but probably half way through the summer. Thanks again!!!

Lmarth

zog02-I'm glad that things worked out for you. All the folks that responded to your thread offered good suggestions. A lot of the names appear frequently as they've tried to help out fellow boaters. Personally, I appreciate your closing out the post by indicating what the problem was. There have been threads with 20-30 posts where the thread just goes dead. Most of us are glad to help out but would appreciate the courtesy of knowing the outcome. You appear to have logical troubleshooting skills. Now go help someone else! Later...Lou

aex

probably exhaust manifold to cyl head . you stated it was fine prior to doing this work.

SeaRay Jim

See #18