Steve Schmidt

In my experience with them in the racing world where they are running wide open most of the time the lifters and valve springs where the weak link. at around 120 hours the pins in the lifter rollers would start to get loose and the springs started getting weak. the inner spring especially would be a problem. on the pleasure boats where they are run at idle to 3500 rpm most of the time it takes a lot longer to see the wear. In reguard to the question of why cant the motor last the equivilant of 150,000 plus miles? take your new car out and run it 5000 rpm nonstop and push the clutch in and out repeatedly and see how long it lives.

45sonic

I've got three of the carb 500's does that mean I have to replace the springs in all three at the same time. BUT I don't have the money to do it all at the same time. Can I just wait til one breaks then use the other two until one of them gives out then I'll have to fix them or ????????????????

enticer

I would wait until 2 of them break and them you still have one motor to get you back to port and then negotiate a bulk price on 2 motors...........which no doubt would be cheaper than doing two separately

PS.talked to the people at Merc HP today. (finally got a response)and they say they have nothing in writing about replacing valve springs. But they feel depending on the use of the motors runs anywhere from 250 hrs (racing) until 500 hrs (pleasure)

jdnca1

I replaced mine a couple of months ago @153 hrs, (2000 500EFI's) they were in pretty good shape, but a couple getting soft....probably would have made it to 200hrs. If you are a gambler and want to risk beating a lifter out of your motor then I'm sure you can press it more...not worth the risk to me. One thing that would NOT have made it thorough the season were the "junk" OE GM head gaskets.....which I can't believe Merc uses.... I had one going between #5/7 and between #3/5. I used ISKY's tool room XP endurance springs, Fel-Pro gaskets, and went ahead and had a valve job done. You can do 2 motors right, for under 1500.00 in parts.

Dock Holiday

I have 500 EFI's, just turned over 200 Hours and the engines run Great, and have been very well maintained.

At the Miami boat show this February I asked the question about the valve springs to two of the Mercury guys there and this is what they told me.

" You are good for 400 hours no problems, between 400 and 600 hours you may be pushing it and need to do an inspection and repair as needed. The golden hour is 600 hours!"

I have ran this by two mechanics that I trust and they say the same thing.

Currently I know of a 38 Donzi with 380 hours on the 500 EFI's and the engines have never been opened. His mechanic tells him to leave them alone, he is okay at this time! The only problem he has is a small oil leak on the front side of the port engine.

These 500's are very tough engines. Take care of them and they will run a long time!

BAJA WILL

MissHapp

Replace your springs, you will be very glad you did.

As for anyone who wants to push it over 250hours hey have at it, you will be posting again at the end of the summer wanting to know what a total rebuild will cost you

Oh yea and when I talked to Merc Racing they said between 200-300 hours depending on how you run it, that is the only reason I waited until 275.

WILL

enticer

There is no problem replacing the springs or even giving a credit to the perspective buyer. Buy when it comes down to the point where they use it as a point to bad mouth the boat because it's at it's life expectancy that's different.
I think it might come down to "who" has everyone talked to at Mercury. Because I did talk to Mark M yesterday and he said what is posted above

Canada Jeff

I'm with 27 Fountain!

I just did mine at 248 hours, and there were soft springs! Tested them after change! Also another noticable difference is how qiute they are at low rpms now. I hadn't noticed it before, but all hear now is the drive!

Downtown42

If the guy was a jerk then you have a point.

If not, then you want some objections in a sales negotiaton from the buyer. You can address it with your point and let him win. The winner will be you with cash in hand and boat down the road!!

Looks like you own 2 now?

ActiveFun

Does anyone have a price on this spring replacement job??