Ok I feel kinda of dumb, I have 2 blue 500 efi engines that I want to rebuild and keep it stock. I have read and understand that this engine is mostly the same as the GM crate engine 502. I want to go through this engine and refresh everything. One of my engine broke a valve spring so I figure I will just got through the entire engine. I bought the boat used and don't know much about the history of the boat. I do know for sure they have never been gone through and they have about 650 hours on them, From what I am reading I have been very lucky. So I want to pull both and have the heads redone so here are the question I have, Please keep in mind I want to stay stock,
1 what are the specs on the torque specs on the rods and mains.
2 Who offers the best rebuild kits? Or what are the best parts to use.
3 I also hear I should use a special valve springs and lifters, What about the rocker arms, is it worth the cost to go with roller rocker arms also?
4 Head gaskets what is the best?
5 Pistons rings any idea on what should be the best.

Really my plan is remove the engine and send the heads off to be reworked, Send the block to be cleaned and honed out and replaced the bearing in the mains and rods and cam bearings. I know when I get it back it will have been stripped of all the paint, I really like the blue paint that mercury used, how do and where do I get the paint to repaint the engine. Sorry for the run on questions, but I cant seem to find all the straight answers in one place. I would think I am not the only one to have gone through this. Again any advice and suggestions are greatly appreciated, From what I have seen and read on here most of you guys are great and I thank you in advance!!

What boat are the engines in Jim ???

You should really purchase a Merc 500efi service manual. It will have all details and specs.
The block and heads on 500efi's are painted black.
If you use the advanced search function and read back in some older threads you will see lots of info.
There is nothing set in stone and there are many opinions on what is "best"
You should for sure get your injectors cleaned and flowed.

Any suggestion of a company to have the injectors cleaned and flowed? Not sure if this would be done on a typical rebuild if not on the build sheet.

Thanks!

Smitty ( Articfriends ) on here does them, send him a pm

x 2 and is in MI also.

+ he knows these injectors and their issues pretty well.

the clunkers sitting in front of me
since I gave out alot of the indepth info on the 500 efi injectors a couple of years ago and the real issues plus offer the fuel injector service as well for over 9 years completely, all gas side fuel injectors. Here is the jist once again for anyone that missed it.

THEY ARE GM MULTEC JUNK. Would not waste the time to use 35 year old out dated failure prone injectors period. GM stopped these over 10 years ago and most whom test these exact style injectors throw them in the trash.

These were sent to me --- 4 engines worth to valid most likely engine failure. -- 32 HP 500 efi injectors and 25 percent do not even flow anything. Completely stuck close. This is very common as well with this style of injector. I am telling straight up - and I really do not want to even flow test yours cause the odds are most likely I will have bad news for you. Thats how straight up I am about these clunkers. Have no idea why anyone would use these currently with a stand alone ecm since injectors have come along way especially in the past 6 years with all the injector testing going on with many companies. Anyways down the road I should have a plug and play replacement for these.

Last week testing 32 500 efi fuel injectors pics above

BUP,

Is there currently a replacement injector other than the GM junk ones?