Replace springs How many hrs?
 

I would like to know what amount of hrs before changing springs and retainers on a pair of 275 hr 500 EFI's. How much should it cost at a reputable shop?The motors were not run hard and are well maintained,I thought that the carburated 500hp motors had a moisture problem and springs were failing?
When the 500 EFI motors came out I thought the spring problem was solved.Can someone shed light on this?

I would say you are getting in the hour range for new valve springs. They might be ok for another 100hrs, but replacing them is cheap insurance against a major failure. I'm guessing around $1500 for both engines.

I agree with Griff your in the range. Lay up time does not really help springs so number of years in service plays in along with hours. Many if not most engine failures are initiated be spring failures.
Jim

I am in the same exact situation with 500EFI's. Could someone shed some light on what parts to buy and where to buy? Thanks in advance.

The moisture problem was prior to the thermostat for the oil cooler. I know the HP450's were real bad for the condensation, which rusted the valve springs. Now replacement is mainly just a maintainence thing. After so many hours the springs have been compressed and released so many times that they have fatigue problems. I would say you're going to pay 8 hours labor per engine at least.

Get them all replaced now... The springs are the weak link in our HP500's. Springs are so much cheaper thaan engines. I bought 3 engines this year, and I only have room for 2 in my boat at a time. Carder

It's time.....it's cheaper to service them now then complete re-builds later.

Thanks guy's, I was looking for an actual mercury reccomendation on hrs.If there is one.Some of those motors have gone 500-600 hrs and more without changing the springs.They used to run the piss out of those engines in F1 boats.But preventative maintenance always saves money in the long run.I would like some more input if anyone has it!Thanks again!

Merc wants the heads pulled and the springs and gaskets replaced at 200 hours.

200 hours on the 500EFI and 275 on the 525EFI.