Engine Knock 3.0 Volvo penta

[Kronoss]

So, I just fixed an issue where i had water in the oil, by getting a new manifold, now that i put it all together, engine runs and starts without a hiccup, but there is a very loud engine knocking sound, it sounds pretty brutal in person, to the point that you are afraid to even give it any throttle.

Here is how it sounds:
20131030_122352.mp4 - YouTube

Here is a video with the spark plugs and valve cover off, no knocking sound
20131030_130128.mp4 - YouTube


Because of the water in the cylinders coming from the manifold, my compression test was showing 300+ on one cylinder, and 280+ on the rest, after the issue was resolved, it was 150-170.

Also, I peaked with a tube camera via spark plug hole, and as i was bumping the engine while camera inside, the tube camera might of pinched a valve, but not very sure on this one.

 

[Kronoss]

Re: Engine Knock 3.0 Volvo penta

Also, after running, here is how the spark plugs looked, from 1-4 in order

http://i.imgur.com/bdFLUNc.jpg

 

[Walt T]

Re: Engine Knock 3.0 Volvo penta

Death rattle. Water probably got hammered and something gave a little.

 

[Bondo]

Re: Engine Knock 3.0 Volvo penta

So, I just fixed an issue where i had water in the oil, by getting a new manifold, now that i put it all together, engine runs and starts without a hiccup, but there is a very loud engine knocking sound, it sounds pretty brutal in person, to the point that you are afraid to even give it any throttle.

Here is how it sounds:
20131030_122352.mp4 - YouTube

Here is a video with the spark plugs and valve cover off, no knocking sound
20131030_130128.mp4 - YouTube


Because of the water in the cylinders coming from the manifold, my compression test was showing 300+ on one cylinder, and 280+ on the rest, after the issue was resolved, it was 150-170.

Also, I peaked with a tube camera via spark plug hole, and as i was bumping the engine while camera inside, the tube camera might of pinched a valve, but not very sure on this one.

Ayuh,.... When was the 2nd vid shot,..?? No spark plugs in it Right,..??

Before or after the compression test,..??

Before or after it was run in the 1st vid,..??

Did ya crank it on the starter with the spark plugs out, Before the compression test,..??
Were All the spark plugs out Durin' the compression test(s),..??

Has the oil been changed,..?? When,..??

How much "Over-Full" was it,..??

 

[Kronoss]

Re: Engine Knock 3.0 Volvo penta

Second video was shot with no spark plugs, just after the first video was.

After the compression test, i suspect somewhat the compression test is what messed up the engine maybe, because it sounded fine during the compression test also.

All spark plugs were out during compression test.

Oil been changed, but turned into milk due to manifold leaking, then changed again, and got milky again, Oil was changed often, but sat about 1 week with water in the oil.

Was not very overfull, just a little bit over.



A friend of mine suggested that it is the rod bearing, and i need to take apart the whole engine to fix it... fun...

 

[Kronoss]

Re: Engine Knock 3.0 Volvo penta

Well, the fix was very easy, but I decided to take apart the whole engine anyway.

Here was where the engine knocking came from:

back of the flywheel bolt was completly lose, and all the bolts were hand tightened.

 

[dypcdiver]

Re: Engine Knock 3.0 Volvo penta

What a pain. But I don't like the oil on number 3 & 4 spark plugs. I am a little concerned that the piston rings are letting oil past, possibly they are rusted into the grooves or even maybe some rust in the bores due to standing water while the manifold was leaking. Perhaps you can get a decent view with your camera.

As you have the motor out I would be inclined to remove the cylinder head and check everything, regrind valves etc. Pull the pistons and check the rings and for what they cost a new set of bottom end shells would give you peace of mind to enjoy you boating.

 

[aerobat]

Re: Engine Knock 3.0 Volvo penta

As you have the motor out I would be inclined to remove the cylinder head and check everything, regrind valves etc. Pull the pistons and check the rings and for what they cost a new set of bottom end shells would give you peace of mind to enjoy you boating.

that is for sure more easy to write down than to do...

 

[Walt T]

Re: Engine Knock 3.0 Volvo penta

True dat Aerobatty. Way to go Kronoss, way to slay that death rattle

 

[Kronoss]

Re: Engine Knock 3.0 Volvo penta

I did actually take the whole thing apart, new piston rings, new rod and main bearings. Rod bearings were just a little bit scratched up, from water inside the oil.
Honed the cylinders as well, they didn't have any rust, and were smooth.

Did not regrind valves, I left them overnight with water on top, none of them leaked.

 

[dypcdiver]

Re: Engine Knock 3.0 Volvo penta

Sounds good to me, do you get to enjoy using the boat in the winter down in Florida?
I have just taken mine out of the water until next May.

 

[Kronoss]

Re: Engine Knock 3.0 Volvo penta

Not quite ready for water yet, engine is still in the garage, taking my time to restore it and make it look brand new, repainting/powder coating all the parts.

One problem I have found, is that the timing chain cover is very rusted, and cant find a place to buy without spending 300$.