I am posting from my wife's computer.........because I believe I got the new "boot virus" and my puter is puked.
ANYWAY..........it has come to my attention that the boat I am trying to sale has 150 hrs on it and the person looking at the boat says that it needs new valve springs. Now, I thought that this was only for big blocks that a lesser than 500 EFI's, because the springs that they sell you to put in 500 HP's and etc are the 500 EFI springs and kit. I thought I read something a year ago or so, that 500 EFI's have no valve spring issues. ANY INPUT would gratly appreciated. Because trying to talk to someone from Merury Racing is like getting an interview with the president or pope.
For example.........if you could run your boat from start up to shut down at 100 mph....then 150 hours would only be 15,000 miles. So, they don't make a motor that last longer than 15,000 miles or even 20,000 miles (200 hrs)????

Now I am going to work on my puter

Boats cannot be compared to mileage. There is way more load and stress on a boat motor. If you want to sell the boat, depending on agreed price, do what the buyer wants and be done with it. Arguing with him will kill your deal.

The HP500 carb motors had the valve spring problems.

You should be fine with your EFI motor.

Generally, the springs should be replaced around 250 hours as a scheduled maintenance item. This is not the same problem the carb motors were having.

Via Bob Teague PERSONALLY...

I just sold a boat a couple weeks ago with a 200 Hour 500EFI. The prospective buyer was concerned about the "Valve Spring Issue."

The buyer called Bob and he assured him the Valve Springs were not a problem or issue on this motor, (1999 500EFI); that Mercury Racing had fixed this issue by introduction of the 500EEFI.

That prospective buyer is now the new owner.

Bingo

Downtown 42...........I do have an idea that they do not run the same, but it was a figure speech that should paralleled somewhere in use. And I know I don't run the boat at 100 mph from start to finish...........and even at that with 150 hrs.........should be alot less that 15,000 mi (so to speak)

Sydwayz....that is what I thought I remembered in an article Teague had done for a magazine.

Thanks to all for the input
Went to the shop and brought home my laptop....................still have not found out the problem nor name of the virus the main computer has

I have a friend that has 500EFI's and he had an issue with the starboard engine running roughso he tok it in to find out what was up. A couple of the valve springs were rusted and broken. He had the springs replaced in both engines just to be on the safe side. He was told by the shop that replaced the springs that condensation can build up under the valve covers and the springs will rust and break and that he should have the springs replaced every other season.

I'd put springs in it if I were keeping it.

I'd give the guy a $500 discount on the boat for valvesprings if a buyer was stuck on that point. That'll buy the springs and gaskets. The rental of a spring compressor at AutoZone is free, and a homemmade air fitting to put in the spark plug hole is about $5. Let him supply his own labor...

Wow, this again

I have personal experience on this, ALL 500 efi's need their springs replaced around 250 hours at the most. I waited until 275 and had a broken inner spring, no damage but could have been, also the motor ran perfect with the broken spring.

Hey if people don't believe me just don't change your springs and you can learn the hard way.

Will Murray