stalling when raw water valve is opened

[tworail]

Hi folks,

I'm trying to get my A4 back up and running (on land atm) after having not tested the engine since summer 2019 (again on the hard). At that time it functioned correctly, and got to operating temperature in 5 minutes or so. Ran it for 10 minutes, then called it a day.

This year I have replaced the plugs and CAN get the engine running, but as soon I dip the test hose back into the buck the engine slows down and dies.

Does this strike you as more of a fuel / carb problem vs something else? I have not been able to find this particular condition in the manual or searching the forum.

The last test I did I removed the cover plate to check the impeller and let the water drain out completley before trying again. After running for 30-60s, put the hose back in the bucket and it slowly died.

Thanks in advance for your feedback on this one.

[ndutton]

Please do a cooling system pressure test ASAP. In the meantime, squirt some MMO (Marvel Mystery Oil) into the spark plug holes and turn the engine over with no cooling water being drawn in.

Check the oil color too.

[tworail]

Oil is clear. I did do the mmo treatment prior to starting. Is there a how to on doing the pressure test accurately?

[ndutton]

Originally Posted by tworail

Is there a how to on doing the pressure test accurately?

Yes, found in the forum Testing Protocols category.

https://www.moyermarineforum.com/for...ad.php?t=11111

[tworail]

I wasn't able to do the pressure test for lack of having the proper tool in the guide, but I did have a compression tester which showed 0 compression on cyl 1 & 2 - stuck valves. They could not be freed using the allen key or similar hack so I removed the valve cover and freed them manually and then hit the starter another 5-10 times to get the #2 valve free and working which was the more stubborn one, after liberal application of MMO and PB blaster in the cylinder.

Everything running great now