Offshoreonly.com - HP500 efi Rebuild

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Quote:

Originally Posted by Raylar (Post 3577247)

God, I sometimes read some things here on these threads that get me shakin my old head! .......................

Ray,

I sometimes wonder if people actually follow their own advice they give on here?

Some observations I have seen in REAL LIFE!

454 and 502 MPIs with over 1000's hours on them, never touched.

3 Cast 330hp BBC with blowers, square port intakes connected to round port peanut heads :eek: all 3 are still running strong, no issues.

A 454mpi CAST non mag, with procharger, 140 hrs....no issues.

2 CAST 496ho's with Whipples, no issues, no internal changes, one is near wide open all the time,

Twin 700 HP engines on a 388 hustler, standard bravo drives for 100 hours......no problems, 94 mph.

Every time you start a boat it is a gamble that something may break. 1000 to 1 odds doesn't mean you have to bust your budget because of a internet rumor that a problem happens to "all of them" This site a great place for info, however if you ask enough questions some members will try to make you believe you need to rebuild every weekend, and your bravo drive will explode as soon as you put it in gear.

I have been on Vettex's boat, it is one owner and has had an easy life. Do your tests, and changes the springs with compressed air. Then spend some time trying to get that pig to break 70 mph :)

Quote:

Originally Posted by Knot 4 Me (Post 3577683)

Buddy had his 500 EFI's done last spring by Brad Smith. 2003's with 300 hours. Compression and leakdown numbers were good. Head gaskets were all but gone when the heads were pulled.

gm is useing inferior head bolts that come from china,the bolt head has an X on it,they stretch after enough heat cycles,dont reuse them,buy the quality arp bolts,most of there chinese parts are junk,i recently did a gen 6 engine that had these bolts,it also had a scat crank,in doing some research,i discovered that gm is scats biggest customer.its a shame that one of the largest companys in the country buys chinese junk.

4Bus, I hear you. This is my first rebuild that I'm getting involved with so I just wanted to make sure there isn't a known problem that I should be worried about.

I need to have someone look at my injectors as well next season and work on my props and try and get the pig moving better, I'm not satisfied with 72 at all. Its certainly time to get things back in order.

Scan the ECM's to see what rpms the engines have been ran at for how many hours. Do leak down tests.
Go from there based on the results of both tests. If the scans show mostly idle and cruise rpms, and the leak downs are good, I'd just replace the valve springs.
If leak downs are marginal, I would do complete valve jobs and head gaskets.

I would not use Merc springs. I would use Isky's or Comp Cam springs.