volvo 260a water in cylinders

[bayliner in elkmore]

I just finished installing new manifolds and risers on my 86 bayliner contessa with volvo penta 260a chevy because it hydro locked. i replaced these parts on the advice of another boater due to his experinces in the past.the engine restarted and ran okay at best i turned it off and upon trying to restart it, it locked again. again #3 spark plug was wet with water. has anyone run into this before?? before i pull the heads off this beast..

 

[Don S]

Re: volvo 260a water in cylinders

There have been reports of some aftermarket manifolds not haveing a flat surface between the manifold and riser, Might run a flat file across the surfaces and see that they are flat.

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

Thanks Don However I Think I Have A Much Bigger Issue. The Reason I Initially Changed The Manifolds Etc., Was A Hydro Lock Condition And When I Removed #3 Spark Plug Water Poured Out As If I Dumped Out A Soda Bottle. I Suppose I Should Have Taken A Little More Time To Diagnose My Problem Rather Than Putting Out The Money For The Parts???? But As The Saying Goes "live And Learn". Well I'll Post Another Thread Once I'm Inside The Engine So Your Not In Suspense!! Lol! Hopefully This One Won't Cost As Much As The First Trip Into The Engine Hatch.

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

okay well i found a crack in the exhaust valve seat on #3, so i put heads on and used a set of automotive head gaskets. bad idea??? we took it out for a test run last night, upon full throttle acceleration it made a tinny/hollow sound from the exhaust and i heard what i thought to be pinging so i tried to adjust the timimng a bit to reduce the ping. well the pinging went away briefly and we were about 400 yards from the dock when the engine overheated and stopped suddenly. so i quickly commenced to replace the water pump impeller that looked ok(still had all its vanes and was still pliable) and tried to restart the engine only to hear the starter struggle to even get the engine to move. so i then CALMLY removed the #3 plug and about a cylinders worth of water came pouring out. anyone have any other similar trip down this lovely road to the poor house before i pull the boat for the season to build an engine,, ( a marine engine) my god i sound like every other car mechanic in this forum! LOL . intake manifold rotted out? broken block? the engine ran great tied to the dock i let it come up to temp 6-7 times started it up about 30 times between cahnging the oil and setting timing & idle speed i'm just very frustrated right now and will be back inside the engine tonight.

 

[Maclin]

Re: volvo 260a water in cylinders

My first thought is that the problem is in whatever was there before the head was replaced.

Exhaust manifold, riser, riser joint gasket, etc.

I would center the first part of my investigation around the riser and manifold and the surfaces and gasket between them. As Don S mentioned, make sure the surfaces are flat. Make sure the riser has a good amount of metal left in the passages and the mounting surfaces between the passages. Look for water stains on the manifold that may indicate the riser joint is leaking.

The intake manifold does have water passages, but it is usually not the culprit when water is entering a cylinder. I do not think it would affect just the one cylinder, and most likely would be putting water into the crankcase and not the cylinders.

I believe I have seen a seasoned poster here mention that the top 5 reasons for water entering a cylinder are (I modified it some, but you should get the idea):

1. Exhaust manifold and/or risers or riser joint gasketing
2. see#1
3. see #2
4. exhaust flappers gone, big wave hits stern with engine not running
5. engine dieseling/reversion

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

thanks mac, do you know if the volvo outdrive has flappers and where they're at? the exhaust exits through an outlet just above the prop. and the manifolds and risers are new, can that still be an issue?

 

[Maclin]

Re: volvo 260a water in cylinders

I am not sure about flappers on your year. I know later model Volvos did away with flappers in the exhaust y-pipes. Mine (290DP with AQ271C, 1991 model year) just has the non-hinging rubber flapper tabs on the outside of the drive on the cav plate exhaust exit.

In my opinion missing or crummy flappers typically would not cause a recurring water intrusion on most boats. The risers are pretty high and the water would have to be forced up thru the cav plate exhaust opening then up thru the Y-pipe and on up into the riser. I try to keep the engine running if the swells are high Dswells, that would be funny if you knew how small the lake is where I go the most!). I always throttle down slow and let the engine stay up in rpm's as much as possible to meet the stopping requirements and always keep it running until my wake has passed underneath me. (Actually on my lake, my wake causes most of the swells especially if we are tubing in circles).

Now, as to the new stuff, all mating surfaces should be perfectly flat and smooth, need to be checked with a good straight edge. If you have both risers off then you can put them up against each other, they should mate up perfectly with no rocking and NO light should be visible thru the joint from any angle. Slide them around on each other make sure the entire surface is flat. Also verify the exhaust manifold mating surface, has to be perfectly flat.

If they are not you can have a machine shop face them for you, shouldn't cost much. They can check them for you also if you are not sure they are flat enough from your gauging efforts.

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

yeah the exhaust pipe leaves the back of the engine and dumps into the bellows almost below the level of the crank. i was thinkin that i would almost have to be going in reverse about 15 knots to fill up the exh-pipe. and i'll also recheck the mating surfaces on the risers again but the more i think about it, and believe me i'm trying not to, i think my problem lies in the block. and can anybody tell me what kind of pressure the cooling system is under when the boat is running at speed ? although it's not a closed system like a car are the pressures close 10-17psi?? just curious, anyway thanks again mac 20+ years on cars first boat. i'm divin' back in it tonight keep you informed!!

 

[Maclin]

Re: volvo 260a water in cylinders

The thermostat blocks flow thru the block until a certain temp so there is some but not near like the 15-17 psi in a closed system because most of the water is allowed to bypass until the thermostat tells it to go on thru the block. But I cannot think of a block issue that would only affect one cylinder that way. Most block issues with cooling dump water into the crank case.

As mentioned before.....

1. Exhaust manifold and/or risers or riser joint gasketing
2. see#1
3. see #2

 

[jerryjerry05]

Re: volvo 260a water in cylinders

1986 Volvo with a?????275 drive???? 280 drive???? You in fresh or salt water
The 275 needs a cone shaped flapper on the exhaust snout.
The 280 has 2 rectangular flaps at the exhaust port.Or it also has an exhaust bellows with internal flappers.
It's possible you have a cracked head.Then it's possible you have a poor mating surface between the riser and manifold or a bad gasket.
Remove the manifols and run a hose to it and flush it out.
Water should only come from the end of the riser.Jerry

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

i got as far as running water through the engine via the impeller inlet hose to the thermo housing and could hear gurgling from under the carb. pulled the carb and there was water laying in the intake????? how in the world did it get there? any ideas? i guess i'm looking at a major problem?, cracked engine block? i'm gonna pull the heads when i find a couple spare hours but any help or past experiences will be greatly appreciated. thanks all!!

 

[Maclin]

Re: volvo 260a water in cylinders

Do you mean water on the inside of the intake manifold right under the carb intake holes? Wow.

The intake does have water going thru it at the front, I mean heck that is where the thermostat housing is. Those passages just mate up with the passages from the block. If water is getting into the actual fuel mixture runners then that manifold is horribly rusted and needs to be retired.

Pulling an intake manifold is straight forward enough, sounds like to me that is the next thing you need to do.

 

[Maclin]

Re: volvo 260a water in cylinders

Is this a raw water cooled salt water boat?

 

[bayliner in elkmore]

Re: volvo 260a water in cylinders

i looked at the intake with great care because thats the only way ithought i could possibly get water that high in the engine. i cant see anything wrong with it?? oh yea fresh water upper chesapeake bay.