Help, question about an HP500EFI engine
 

I need some opinions on this, I've been reading previous posts. I'm looking at a 28' boat with a single HP500EFI engine it has 270 hours on it and has been well taken care of. It looks like I should have the valve spring replaced with either Isky or Comp Cams how much should this cost? Is there any other thing I should have done. Does this need to be done every couple hundred hours of longer now that the factory springs are replaced with stronger ones. I'm nervous about buying a boat with this engine and thinking I should look for a boat with a 496Mag HO. My previouse boat had 7 seasons on it with the 496 and never had any troubles.

Thanfs

Depends on what model year you are talking about. Early 500EFI motors had bad springs, but the later ones are O.K.

Give us more info. I would also see if you can do a leakdown test to get the true health of the rings and valves.

It is my understanding also that the problem was with the early HP 500efi's and the carbed HP500's. I have 330 hours on a pair of 2000 efi's and they run great.

Go blue.... worth every penny. I have one and have had nothing but good things to say about it , I did however pull the heads and do new head gaskets and top end build but only because I was going with a supercharger....every thing was good upon inspection. Great platform for adding power. Much better and stouter than a 496. Don't be nervous about going blue.


Bryan

Valve springs and lifters should be considered wear items and replaced every 250-300 hours on all HP 500's and HP 525's. The cam profiles on these engines are much harder on parts than the 496's. But that's why they put out so much more horsepower.

what is the cost to do the valve springs and lifters

The last one's I did cost about $ 1500 to do 2 engines,
( springs, lifters, seals, retainers, keepers, gaskets)
but that didn't include my labor.....and that was a couple of
years ago.

As posted above, Springs (Comp 929) Lifters (Crane), Cometic Head gaskets, I would also do the rings. Merc uses the GM low tension that burn some oil. Hone with a 400 grit and use Speed Pro metric standart tension rings, file fit. I have rebuilt about 6 of these in the last year or so. The rings crumble when you take them out. I also replace the timing chain with a true roller. Parts & machine work are at $2K. If you cant do all the work you will probally pay a reputable marine shop $4-5K to do the work. It definately a better motor than the 496.

I will argue a bit here about whether HP500's EFI or Carbed are better than a Merc 496.
The Mercury Racing HP engines are fine motors and they cost a lot more up front for the added features and upgrades. The analogy is kinda like comparing apples and oranges on a cost of similar features basis.
If you have to rebuild or upgrade a lot of parts on the Mercury Racing HP engines the parts costs and rebuild expenses will not be inexpensive.
The biggest reason the 496 is comparable or even sometimes in my opinion is the closed cooling that the HP500's don't come with. If you boat in salt or brackish or high alkaline fresh waters this advantage will be a huge advantage over the life of the engine.

I can say without question that the 496's will go 500 hours plus and in many cases over 1000hrs without spring replacement or rebuilds and re-freshen and they certainly don't disassemble wit piston rings in pieces. They are also equipped standard with true double roller timing sets nad standard 10 quart oil pan systems.
If you want to compare our HO525 and HO600 Raylar reworked 496's, they definitely step up the level of stock 496 Merc engine
horsepower and torque and provide hundreds of hours of high performance use without valve spring replacements or low hour rework.
Guess I am obviously biased here, however when you compare the 496 engine family with the HP 500 family of engines on a "apples to apples" basis the Merc 496 engine family will hold its place just fine and at a usual lesser cost basis both initial and maintained basis.
In any event its a buyers market in performance boats right now and either choice with the services of a good mechanical survey or inspections should get you a nice boat with a good engine package with either of these choices!

Best Regards,
Ray @ Raylar

How much is your HO525 and HO600 kits?

I have had hp 500 efi 300 hours no problems , 525 200 hours no problem, now running 600 sci 100 hours ,blue has been very dependable to me 3 for 3 so far

Ray

You have more experience than anybody probally with the 496 than anybody here so thanks for the insight. It's something we are not familiar with so we turn the other direction. I have a 496 in my 2500 suburban that is getting close to 200,000 miles. Nothing but some oil changes. I am burning about 2 quarts every 3000 mile oil change. That kinda tells me they have low tension rings but I really do not know. The 502MPI could go the type of hours the 496 but with the reduced horsepower as the 496 (425HP) Its really a softer cam that causes the longer life. I think the 500&525EFI only has about .100 before coil bind. I was just wanting to relay what I have been finding so he knows what he's getting into. We appreciate the 496 input as well. We probally need to dig into these as you have to understand them better.

How does the 290 run with the 600??

How Much is that Doggie in the Window!
 

Thanks Guys. Not trying by any means to bash the Blue motors as they are excellent motors and since the 525, 600's and 700's have hit the market their performance, engineering and reliability speaks for itself. I was just pointing out that in today's tough economic times there are some other lower cost alternatives for the performance boating crowd.
Our Raylar complete HO525's sell currently for $21,960.00 and our complete HO600 with headers sells for $29,840.00.
For those who may be interested we have a custom paint Raylar HO600 with CMI exhaust, custom coil and ecm relocation kits and special polished billet pulley kit, oversize oil cooler and remote oil filter mounts. This engine has about twelve total hours including dyno time and its seriously for sale at $21,500!! This engine would price at over $34K so someones going to get a smoking deal with a warranty on a nice 625HP 89 pump gas motor!! Call me it won't last long at this price! We have to clean out the engine storage area and make room for this winter builds. (866) 496-8181

Best Regards,
Ray @ Raylar

PS, the engine in my attached avatar is a twin for the special offering!

Well, your concerns are well founded....200 hrs. to replace the valvetrain is a joke on such an expensive motor. Where do we even start? First off the 60's designed heads with their big, low velocity ports have driven everyone to big lift cams to make these heads even start to work...the 400+ LBS spring rates just put the whole valve train at its limits. Smaller higher velocity ports don't require giant lift to work well and the requisite lower spring rates are going to add alot of hours and reliability to the motor. This is the secret to the 496/Rayler motors. There isn't any real technoligical leaps to the 496 (sure, some nice small improvements)...its the high velocity ports, sub 400# spring rates that keep the performance and reliability up. I am in the minority here I am sure, but the passing years have rendered the old iron rectangle port head obselete. You could take any modern 260-300cc intake head an easily make a better running more reliable 500hp. I would lean to the 496. Take Care, Dave