Hours on merc 5.7 before problems.

[spfortjohn]

I am in the market for a new boat, My current boat is an outboard and the wife likes the I/O Sundeck 260 (So I guess that is what we are getting if I want to stay married.)

My neighbor has an 06 22 Select with the 5.7 mag and it dropped a valve yesterday, His has 320 hours. Another friend of mine has a 240 sundeck with the 5.0 and his dropped a valve also. Seems like both kissed the and now needs to be replaced with a long block. Big money
piston

1. is this common in the I/O motors?

2. Why does this happen?

Kinda makes me nervous as we current have 450 hours on my Yamaha outboard without any problems.

I know the problems with I/O in salt water manifolds and such need to be replaced every 5 years or so but to have the motor crap out with such low hours does not make sense.

 

[SeaRide]

I have owned mine since new and have well over 600 hrs. on the original 5.7. No internal issues to this date and the engine still makes wide open throttle specs. Fresh water use for the most part.

 

[Phlorida]

I have a 16 year old 5.7l/Bravo with nearly 800 hours on the combo. The setup runs flawlessly and has always been in salt water.

 

[tbirdvet]

The I/O has nothing to do with the engine issues. Something else is happening here.

 

[Dick Whetstone]

I have a 1986 21 foot Glassmaster Regency with 5.7 and Alpha 1 that I bought new. It is used all summer, every summer, at my lake house. No hour meter but both have run flawlessly since new. Fresh water use 99% of the time. I do my own maintenance. Engine oil (Havoline 30W) is changed each year as is the oil filter and stern drive oil. Engine uses NO oil. Fresh water pick up impeller in the "foot" is changed about every 3-4 years. Carb has been rebuilt once. It just keeps going and going and going...............

 

[Hellman Huddle]

I'm pushing 900 Hours!

 

[Big Island Lifer]

My original motor had almost 2000 hours on it before it bought the farm last year. Still have the original Alpha drive with new/ rebuilt block.

 

[fwebster]

There are no systemic problems with inboard engines that make them drop valves. I suspect the boat's maintenance history, how it was serviced and run may have more to do with the valve problems than anything else.

I love Sea Ray boats and really believe in the company and what they do, but if you have problem with i/o's, you might look at a SouthWind boat:

http://southwindboats.com/our-boats/sport-decks/2600-sd/

Our Sea Ray dealer picked up this line to be able to offer an outboard deck style boat. When they were considering the line, they handed me the keys to the 27 ft version and said "Find everything you can that is wrong with it". The list had 2 items on it, and I loved the boat and the way it handled with a single Yamaha outboard. My issues were a seam that should have been caulked but wasn't and part of the wiring harness for electronics was not labeled. You give up the I/O quietness and smoothness of a Sea Ray, but it would big a really good alternative to I/O power.

I just looked at your location and the dealer in Panama City Beach stocks the Southwind and since they are produced in the south, there may be a dealer even closer to you.

 

[Quint4]

A friend in my marina has a 5.7 merc that just came up with "0" compression on one cylinder (2000 Doral cruiser). He also had physical damage to the spark plug. I suppose the valve came apart and some debris fell into the cylinder. He only has 550 hrs on it. He is looking at a reman jasper.

I had a 5.7 in my last boat and liked it. Always started great and ran strong.

 

[Moose]

My 5.7 Mag is pushing 725 hrs. Not one problem. Have full engine service every 2 years, and change oil every 80-90 hours. Have been running full synthetic past 2 years. Always fresh water. I could sell my used oil and maybe make a profit. Just kidding! Use your boat and take care of it and it will last.

 

[Hellman Huddle]

My 5.7 Mag is pushing 725 hrs. Not one problem. Have full engine service every 2 years, and change oil every 80-90 hours. Have been running full synthetic past 2 years. Always fresh water. I could sell my used oil and maybe make a profit. Just kidding! Use your boat and take care of it and it will last.

The key words being "Use your boat"

 

[CV-23]

750 hours on my 1988 5.7L in my CV-23....runs like a top. We average 35mph most of the time and 55mph at WOT. Just hit 800hrs on my 454 Bravo 1. I now know why cruisers build up more hours...we run 6mph quite a bit to save fuel and just relax. I only run on plane 1/3 of the time with the SR, Mike.

 

[Mikeod]

CV's comment made me think. I spend 90% of my time idleing around the lake. Once in awhile I kick it up on plane but not often. What effect does all this idleing have on engine life? Any input?

Mike

 

[KRB64]

I'm not a mechanic but I play one on weekends.

Some folks think a motor should be worked through all of its capacities or else it "settles in" to one extreme range or another.

The only real problems I can think of for excessive idling is to make sure the engine does warm up to operating temps each time so you burn off any moisture within. There may be more of an opportunity for carbon buildup too, what do the plugs look like?

All of our boats have POs but to our knowledge there was no major engine work done before we acquired them. The WE has around 14XX if I remember correctly and the DA has around 18XX and both have no issuse or excessive consumption - except fuel that is...

Dropped valves are not an ordinary occurance on a properly built and maintained engine. Are these of a similar build? Like a recall issue or something maybe?