496 HO tune-up suggestions
 

Doing tune-up on 496 HO'S and need some recommendations on manufacturers and where to buy cap and rotor, plugs, and wire kit. THANKS

Umm, no cap and rotor on a 496HO, hoss.

Sorry individual ignition coils or modulator

You need to find a service manual. I dont think you need to do anything but plugs and oil changes up to almost 600 hours.

FWIW - To change the coils would be a fortune. I cant imagine they are cheap.

Not really much to do besides plugs, oil changes, fuel filter changes - just all the basics. Absolutely no reason to replace coils.

Crank and Rods

2001 Donzi 33 ZX engines has 450 hours, wires look to be ok no burn marks, just new plugs should be ok? How about rebuilding injectors port engine is down 500hp and has hard time getting on plane

The biggest problem with 496 fuel injectors is from corrosion deposits because the internal fuel rails can become corroded. I do have the professional machine to test, flow test and clean fuel injectors professionally. 40 % of my business doing so is 496 fuel injectors from all over the USA, so I see a lot of them and the problems they can have. A lot of times its uneven flow testing results so deep cleaning and special ultra sonic cleaning along with back flushing the injectors properly really brings them back fully ---- 90 to 95 % most of the time after those process.

maintenance - flame arrestor cleaning perfectly clean, throttle body cleaning, IAC muffler min once per year, clean that cavity out - a lot of times it wise to change out the original IAC or least carry new one on hand along with its gasket NEVER reuse the IAC gasket - always install a brand new IAC gasket. Make sure the hose to the IAC from the throttle body area is NOT restricted

1 st GEN ign coils can be a fail point. First gen crank sensor is also a problem and can be an area to check for reduction of RPMs. You will need a scan tool to see if anything else is going on plus the indepth knowledge how to decipher the scanning results.

Fuel filters but not knowing your serial number you can have all different versions and vary from 2 to 3 fuel filters

Anti freeze is often an item missed and so are the end cap gaskets for the heat exchanger

BUP....your inbox is full..How much do you get to do a set of injectors?

Ignition wires??? Wait till ya find out the price on those..lol

For those asking and in PM's.

Injectors top feed GASOLINE injectors in which all mercruiser and Volvo are top feed injectors range from 20 to 25 dollars per injector. See it depends on the 5 dollar difference is how unbalance and or how dirty they are. I change my cleaning fluid and and ultra sonic fluid after each cleaning usage - so if the injectors need multiple cleanings - hence the 5 dollar difference because thats more fluid I have to go thru and depose of properly. The fluids I use are not cheap like some cheapo services will use Kerosene. My flow testing fluid matches the average specific gravity of pump gasoline --- why because you want to simulate real world results.

Also install new basket filters always and O rings. I have been doing this for 8 years now and for marine apps only. I know what to look for and like anything when you do and work on stuff over and over and over again - you become very good at what you do.

Background. My slowest year was about only 320 injectors and my best year ever was 2500 injectors - (testing, flow testing and cleaning).

I actually have 2 machines. One is semi custom built. I really want to stay busy with this year round but only continue with marine apps since I know it very well. Thanks

Both of the machines have internally filters (2 of them ) and I change them after so many injectors runs. You want to filter your testing fluid.

Also some services use tap water and a household cleaner mixed 50 / 50 for their ultra sonic cleaning fluid. That's cheap and really does not clean effectively. I buy my stuff thru an Ultra sonic company in 5 gallon pals. Not cheap either.

I haven't tried these yet but was thinking about replacing mine soon as regular maintance. http://www.amarket.com/imwo808.htm

^^^^^ Man I do not hear that great of things (word of mouth) about this company period just saying

Also the few reviews on google bad

https://www.google.com/#q=reviews+ab...e33f30d3a572,1,

And bad FB reviews as well.

Thanks for all the help.

Thanks for the heads up. I'll look else where.

I purchased a set of marine wires from NAPA, About $85 IIRC.

Would you happen to have a part number?

I got my wires from Raylar. According to Larry they are made by the same manufacture that produces the stock wires for Merc. Had no clue NAPA offered the marine wires. Raylar's run about $220/set. There are no cylinder specific wires. The set contains 4 longer and 4 shorter wires.

NAPA didn't have any for 496 I checked. I think I'm going with Raylar too.

Doing some internet cruising today it looks like some Merc 496 owners have bought and installed Volvo Penta wires. Looks like they can be had for approx $100 or so a set.
Volvo Penta #3861295 and yeh, I guess they have Volvo Penta printed on them. LOL.

Disclaimer: this is what I found as a search...so do your own homework. :)

Supposedly these $111.00 Delco plug wires too...and supposedly come with clips:
MMD Powerline 30600147 - AC Delco 8.1L Spark Plug Wire Set

Here is where I found the info on this Delco Wires from someone that bought and installed them. he notes that they fit exact. comes with clips installed, and the word printing is exact same as what was on his OE wires:
8.1 Wires ??? - Page 3

Disclaimer: this is what I found as a search...so do your own homework. :)