NEW Mercruiser 5.7 with tuliped valves after 29 hours

[JaguarMan]

Purchased a new Mercruiser Bravo crate engine 5.7 325 hp. Installed new manifolds,risers, water pump, hoses and thermostat. The boat ran fine for 29.5 hours and now has water coming out of #8 cylinder. Compression test ranges from 60psi to 125psi, none higher. Mercruiser says that I detonated the engine and may not warranty! What could possibly have gone wrong?

 

[Bondo]

What could possibly have gone wrong?

Ayuh,.... Most likely crud, 'n water in the fuel tank,....

Has the Contents of the fuel filter been inspected yet,..??

 

[JaguarMan]

The fuel tank was emptied and cleaned while waiting for the new engine. Not one piece of sand in the block drains. I think bad engine to begin with, I hope.

 

[JaguarMan]

The fuel filter was changed at 10 hours as per Mercruiser.

 

[alldodge]

What year was the old engine?

What was the timing set at and how was it done?

What did you use off the old engine for the new one?

 

[Scott Danforth]

125 on a new engine is low. I still have 180 psi and I am abusing it every time out. Have over 950 hours. Tuliped valves are a sign of high temps and lean conditions

 

[JaguarMan]

The only things used off the old engine were the alternator, which was 2 months old, and the power steering pump and brackets. Starter was new also. I did notice that the engine was built in April 2014 and sat till the end of June 15 when I installed. The boat ran great for 28.5 hours. The original engine was a 1997.

 

[Bondo]

Ayuh,.... Is it carbed, Efi, or Mpi,..??

If carbed, Which carb,..??

 

[Scott Danforth]

if the ignition timing was too far advanced, you would have had detonation, high combustion temps, and that would account for the motor eating itself.

 

[JaguarMan]

The engine is being pulled and sent back to Mercury to be examined this this weekend. I am sure they will blame me for something and not stand by their warranty. The carb is a Weber that came with the engine.

 

[ksmauck]

I have a 98 Mercruiser that had 4 tuliped valves. I had what sounded like pre-ignition at higher rpms. I have since learned that if you have no damage to your pistons and just the intake valves it was likely caused by a fuel problem or an over-propping problem where the engine lugs. My guess is fuel and probably a lean condition. The motor came with a new carb? Or did you use the old one?

 

[Bondo]

My guess is fuel and probably a lean condition. The motor came with a new carb? Or did you use the old one?

Ayuh,.... Not always, but usually the problem is in the boat's side of the fuel system,.......

Bad fuel, crud in the tank, water in the fuel, plugged vent,....

 

[JaguarMan]

I received an answer from Mercruiser today. They said all the cylinder head bolts were loose! They said I must have not checked them while installing. Are they kidding me? They said water was entering the cylinders and I should have known that. The engine was never ran for more than 30 minutes every time I went out!

 

[alldodge]

Merc is saying that you bought a long block and you should have check the heads bolts? That makes no sense

 

[300sflyer]

Agreed... That makes no sense. If they were torqued properly in the first place, they would not have come loose.

So where do you go from here? My advice would be to pull the heads, have the valves redone, and reassemble with new gaskets. Oh ya... Then send Mercury Marine an invoice for the parts and labor!

 

[JaguarMan]

The engine came complete with aluminum intake, new carb, fuel system, and new Thunderbolt 5 ignition system and wiring harness. All I did was install a new alternator and my p/s steering pump. Even put new Mercruiser ecoated manifolds and risers and flappers. Still waiting to hear if they are going to help me!

 

[Rick Stephens]

The engine came complete with aluminum intake, new carb, fuel system, and new Thunderbolt 5 ignition system and wiring harness. All I did was install a new alternator and my p/s steering pump. Even put new Mercruiser ecoated manifolds and risers and flappers. Still waiting to hear if they are going to help me!

Wow. That should arrive considered ready to roll. I would have a lot of trouble accepting that I am supposed to have re-torqued head bolts. How about main bearing caps? Double check that that used the right rings..... maybe they left out the main oil seal.

Disgusting.

 

[JaguarMan]

http://www.marineengineparts.com/en...ine-5-7-liter-325-hp-with-fuel-and-spark.html

This is the new engine I bought. Came with a 3 year warranty.

 

[JaguarMan]

Sorry, it is a Mercruiser 8M0079531 Bravo Crate 5.7 liter, 325hp with fuel and spark.

 

[Rick Stephens]

I'd love to see their warranty. If it is written so they can get out of covering head bolts not tight enough on a crate motor, I would think everyone needs to know that. No reason to ever buy anything from them again.