Ring seating

[goodnuss]

I had Merc 454 rebuilt and bored to 496. Also had ne high torque cam added.<br /><br />Engines now have 25 hours and continue to use oil. The current rate is 1 qt. every 5-6 hours. This means rings must not be seating properly.<br /><br />Is there a way to run the boat to see if the ring can be seated or do the engines have to come our and be redone? I know the work done was good and the rebulider is at a loss on why this is happening. <br /><br />I am looking for any knowledge out there that moght lead us in the right direction.<br /><br />Appreciate you help with this. nusshome@aol.com

 

[jimmythekid]

Re: Ring seating

a bad pcv valve will suck oil like no tomorrow, check the hose leading to it, and if it has any oil in it replace the valve, i have seen brand new ones that are bad out of the box, I only use OE ones

 

[jimmythekid]

Re: Ring seating

also do not use synthetic oils until the engines are well broken in

 

[KaGee]

Re: Ring seating

What about the valve train?? Sucking oil through the seal on the intake valves?

 

[LubeDude]

Re: Ring seating

Do a compresion leak down test.<br /><br />I too am interested in what oil you started with.

 

[deputydawg]

Re: Ring seating

Engines should not burn oil while seating the rings. The rings, if properly installed with the end gap measured and all clearances correct, should seat tight enough to not burn oil within the first hour or less of running. Proper break in proceedure at the shop should seat everything good. Do a compression test in case one cylinder had the control ring break during break in, or was turned to allow oil leakage. <br />Bad valve guides will burn a LOT of oil too. <br />Check the pcv (posative crankcase ventilation) valve. If ffit has oil around it either the valve is bad or you have a bad ring. A bad compression ring will cause a buildup of pressure in the crankcase and force oil out of the PCV valve.<br />Good luck. This is not normal for ANY new engine even before the rings seat. That phrase is kind of a myth anyway, an engine should be seated and good to go after the first hour shop break in.

 

[Bondo]

Re: Ring seating

I Agree with All the above.......<br /><br />What have you done for the Diagnosis process ????<br />Why have you narrowed the search to the Rings ??<br />

Is there a way to run the boat to see if the ring can be seated or do the engines have to come our and be redone?

If , and Only If , you have Nailed the Problem down to the Rings/ Cylinder Walls.........<br /><br />I only know of 2 ways to Force the rings to seat,+ Break-up any Glazing on the Cylinder Walls.......<br /><br />1 is to go up about 4"s(or more) of pitch on the prop,<br />Then go for a ride, at WOT, laboring the motor.......<br />This will drive the Temps Up... Push it to build the heat up to 200* to 210*.....<br />About 20 or 30 minutes of this Abuse will Usually do the Job..........<br /><br />Or,<br />2nd is to run the motor at High Idle... about 2000rpms.... Free-Wheeling.....<br />And Sprinkle about a Tablespoon of a mild Abrasive(Bon-Ami) into the throat of the intake/carb..........<br />Radical, But it Works..........

 

[Buttanic]

Re: Ring seating

Bondo, I had heard of the Bon Ami trick before although I have never tried it. Are there any long term damage issues that could occure from it getting into the lubrication system, damage to bearings, cams,etc.

 

[rodbolt]

Re: Ring seating

how many thousanths of an inch did they bore it to gain 42 cubic inches.

 

[Bondo]

Re: Ring seating

Are there any long term damage issues that could occure from it getting into the lubrication system, damage to bearings, cams,etc

Nope.......<br />It goes in the Intake,+ is Exhausted thru the Exhaust.........<br />No connection to the Lube Oil....

 

[goodnuss]

Re: Ring seating

Thanks for the info to date.<br /><br />I do not know the the thousand's bore.<br /><br />The oil used has been Penzoil Marine SAE 40.<br /><br />I will post what we try. Welcome any additional thoughts as well.

 

[FreeBeeTony]

Re: Ring seating

Is it possible the rings were not installed correctly? Were the ring "ends" staggered as to not allow oil passage?

 

[deputydawg]

Re: Ring seating

I am still of the opinion that something else is wrong. That much oil loss after that many hours? Do what was said above, run it hard for a while and get the temp up a little. this should have been done during break in at the shop. Put it under a load and work it hard. Also rev it up to WOT under load, pull back to idle, open up, pull back over and over about 5 or 6 times. Make the engine work hard. After 25 hours it should be well broke in by now. I bet you have a damaged control ring, or the ends not lined up right. I have seen "rebuilds" where the ring compressor slips and breaks a ring as it enters the cylinder. If the worker does not re-check their work it may never be found until it uses oil later.<br />Run a compression check on a warm engine. This will tell a lot.<br />Also, with all of this, the heads were worked? If not a valve guide or seal may be bad. Valve seals or a bad guide will burn as much if not more oil than un-seated rings.

 

[LubeDude]

Re: Ring seating

If you installed aftermarket valve covers, they may not be baffled where your PVC Valve is, this will suck an incredable amount of oil.<br /><br /> Dont ask how I know!!

 

[KaGee]

Re: Ring seating

Originally posted by LubeDude:<br /> Dont ask how I know!!

OK..... Can't help it.... Gotta ask.....<br /> HOW?<br />