Tired 454 Magnum
 

I'm looking for a little advice. My 1989 Formula 242LS has a 454 Magnum, 365 hp Mercruiser engine. I boiught it about 4 years ago, when I bought it I could get it to just under 59mph on the speedo. This year I can barely get over 50. The engine has almost 1500 hours, (yes hundred) I know that's a lot, so I did a compression check, all but 2 cylinders were very close to 145, which I think is low, but one cylinder was only 115, and the other was 135.

My thoughts are, this engine is tired, I need to replace it. The question is, what are my options. Assuming I want to spend less than $5000, shuold I go with a crate moter, re-manufactured moter, can I upgrade to a 502, are there any good used engines out there? And what are some good reliable companies to go with for an engine?

If anyone has gone through something like this, I would really appreciate any advice you could give.

Just rebuild it with some hp upgrades. Pretty easy to get 425-450hp out of it, but you will need an exhaust upgrade.
The 145# of compression is about what it should have.

Cliff,

You did not mention where you are located, but in the Southern Maryland area where I am, an 18 year old raw water cooled 454 with 1500 hours on it will have so much corrosion in the block and heads that I would normally not even want to look at it. There are a few exceptions, but that is the norm. Keep in mind when you are figuring out costs that the manifolds and risers will probably have to be replaced also. Figure on intake manifold also. I think you will be hard pressed to do the whole thing correctly for 5K

Just my opinion,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

I have a buddy that just took out a 454 mag and installed a 496 . The 454 has 365 hrs on it and it is complete every thing but bellhousing and coupler $3000.00 obo. Norfolk Marine has done all the maint. mostly run in fresh water and never run hard he is 65 years old.

Tired 454
 

I would be very interested in that motor if he still has it.

Have him e-mail me at [email protected]

I left a message on his voice mail.:cool-smiley-011:

SENT YOU AN EMAIL:food-smiley-007:

242 Formula
 

Still a beautiful boat Cliff. Thanks for the ride, great riding boat. Time for a 502 MPI!
John B's Friend, Nick

I have a 502 MPI Mag All fresh ... complete drop in minus exhaust ... 6500.00

[email protected]