Author Topic: Running issue AC2W  (Read 703 times)

Altonx

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Running issue AC2W
« on: August 21, 2023, 08:23:44 AM »
Copied from an old post but I have the exact same issue, so any advice welcome,
Ok so she starts easily, tick over seems fine but the tick over can be erratic drop off a few rpm then picking up again. But the real issue starts when you increase the revs and run at higher speed for a while all seems ok but if you return to tick over and either cuts out of struggles to tickover.
The problem seems to get worse generally the longer the engine has been running. Also power at speed seems to drop off to.
I have recently replaced fuel lines and filter But it has had no effect on the problem, I have also noticed some white smoke  from the exhaust and slight seawater leakage down the block from the headgasket, would I be wrong in saying head gasket failure leaking water into the combustion chamber?
« Last Edit: August 21, 2023, 08:25:20 AM by Altonx »

cobbadog

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Re: Running issue AC2W
« Reply #1 on: August 22, 2023, 05:36:03 AM »
Hi mate, What was the outcome of that other post where you found a similar issue, maybe try that?
If you have a water leak from around the head gasket area remove the head to confirm that none is getting into the cylinder as that will destroy a piston at best. Ignore it and it might bite you while motoring somewhere and I know I dont like rowing anywhere. Even if you find that the water is not getting inside at least you know it is good there.
Is the oil level rising in the sump? If so you know the head gasket must be done. Good luck in getting it working properly again and keep us informed.
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ajaffa1

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Re: Running issue AC2W
« Reply #2 on: August 22, 2023, 09:12:15 AM »
Hi Antonx, I`m with cobbadog, probably a head gasket, If you are running salt water cooling you will get corrosion between the gaskets and the cylinder block/cylinder head. This will eventually cause gasket failure, water ingress into the cylinders and potentially into the sump. Time for some TLC. From your description of the issue it could also be a governor problem but I would go for the gaskets first.

Bob

Altonx

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Re: Running issue AC2W
« Reply #3 on: August 24, 2023, 01:37:13 PM »
Hi
Thank you both for the reply
The outcome for the original post i found was missing from the forum for some reason, there were 3 posts, the description, the 2nd post (which possibly had the answer) is missing and the 3rd post was just a reply from the OP.
I have sourced gasket sets for removing the cylinder heads, I am aware bump clearance must be checked and adjusted, I just have a bad feeling opening up this old engine is going to be like opening a can of worms, but agree with you both, it has to be done sooner rather than later, the boat will be leaving its mooring very soon and going back into a boatyard for the winter so I will pull the top end apart then and have a look.
A possible governor issue was mentioned, what sort of issues do they throw out?

cobbadog

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Re: Running issue AC2W
« Reply #4 on: August 25, 2023, 12:37:04 PM »
You will realise that these Lister engines are over designed to take a very hard life. My 8hp should have died years ago and withy a bit of tlc it runs like a clock again and if it was a modern engine it would be in the scrap bin. Good luck with it and hope it is as simple as a gasket.
Coopernook - the centre of our Universe.