Merc. 500 HP info
 

Anymore I am a much bigger fan of EFI engines, but I found this 33 outlaw that could be a pretty good deal and it has twin Merc 500 HP engines in it and of course these are carbuerated motors. I have heard those engines had some problems with valve springs, but other than that I have never really gotten any feedback on them. The engines have about 270 hours on them. I definitely don't want to get something I will be wrenching on all of the time. Does anyone know what kind of reliability these engines have, or any problems these engines are notorious for? Any info would be greatly appreciated. Thanks!

My HP500's had the spring melt-down at about 300 hours...
...inner springs had been in pieces for a while, continuing to destroy the top of the heads, then more broke off into a cylinder, and caused crankshaft to break in half.

I would recommend redoing the heads with stronger springs, and then they should be fine.

Carder

I have seen them run 400 hrs and no trouble but it just depends on the guy running the sticks!

Actually the guy running the sticks is a minor player in the spring melt-down.
Merc went to stronger springs after they were determined to be the weak link, also water reversion with their bad cam/ exhaust combos added to spring break-down.
If longevity was soley due to how the sticks were fondled, I would have been able to drive those engines forever...
Carder

those motors have a well known history for valve spring and water reversion issues in the models that didn't have the higher risers. As long as they are caught in time, no big deal. One suggestion mercury had to control reversion is raising idle speed, but changing to taller risers is by far the best fix.

I remember seeing that Bob Teague talked about this issue in depth in one of the teagues on tech section of powerboatmag

Thanks for the info everyone. How much does it usually cost to upgrade an engine with these specifications?

it depends on how much you can do yourself. the heads are going to have to come off. once off, your looking at less than 1K an engine for the valve spring, lock, retainer replacement. They need to thoroughly inspect the heads including the valve seats before they go back in.

The exhaust risers are a different story. You might need to take a picture of one of your existing ones and post to determine if you have one of the earlier "bad" designs or if you are ok. You can find some different risers that are compatible with what you have, you just may need to ask around.

Thanks again everyone I really appreciated it. So with everything said, would any of you buy a boat again with these engines in it?

Once the springs are done these engines run great. The rest of the peices in these engines are all good quality parts . :ernaehrung004:

If that 33 OL is in even average condition with the 500HP's its a steal at that price. Figure another 10k for the trailer and to do the valve springs.

Yea I thought it looked like it could be a pretty good deal. I am waiting for a call from the individual selling it to get the whole background on the boat and hopefully I can go look at it this weekend. If everything checks out I think it may be worth it to buy it at the low price and just redo the springs right away before next summer.

If you are going to do the springs, consider Aluminum heads/springs, upgrade, etc. I ended up doing that and gained almost 100 hp in my HP 500's... better parts, now bullet proof, and the boat never ran stronger.
Tyler Crockett added the Dart Comp. CNC package for us.
CARDER

Awesome. Thank you so much. Everyone has been really helpful.

http://www.teamshogren.com/brokerage...-32-fever.html

http://cgi.ebay.com/ebaymotors/Boats...ayphotohosting

The first link will take you to an image of a HP 500 from a 1998 32 Fountain Fever and the second link will take you to an image from the '99 33 outlaw I am looking at (scroll down and click on the engine pic). It was mentioned that the hp500 had some problems with water reversion. Look how high the exhaust pipe comes up after the manifold on the baja compared to the fountain. Wouldn't this extra height create a higher potential risk for water reversion?

The taller riser prevents reversion. Water can't go up as easily because of the height. The risers on the Baja 500's are the newer version and better. Water is not actually introduced into the exhaust until about 2 inches before the rubber hose that connects the risers to the silent choice diverters. Its a water jacketed riser with holes inside at the end of the pipe.

Thanks a lot Griff. You have been very helpful.

You will want to research valve lifters are in the engine as engines with the "tie bar" arrangement will fail. After the tie bar fatigues and breaks the lifter turns sideways in it bore destroying the cam and lifter. Not to mention sending metal filings all thru the engine. Happened to me right around 300 hours.

There is an updated lifter retainer system, someone else will have to help you determine which style lifters the engine has.

The motors run great, get the valves done and looked at and then run them like you stole them. Tremendous reliable power. They often Dyno higher then rated. Great power

the valve springs can be changed without removing the heads but upgraded heads & cam will make that outlaw wake up.