502 Mag Procharged Fuel Injector Service
 

After running my 1996 502 Mag with self installed M-3 Procharger system(5 lbs) I checked the spark plugs after running W.O.T. for 20 seconds. With the new prop, ran up to about 4700 r.p.m. Took about 5 minutes to wipe the smile from my face. But after that I noticed there was a significant variation in the apperance of the plugs. The average appearance seemed correct. but several seemed to rich one was to the lean side. Running about 39 lbs base and 62 lbs at full boost for fuel pressure. I suspect that I have some fuel injectors that are not operating correctly. I bought the boat from some one who only changed the oil. No other maintainence! When I changed the fuel filter/water seperator I could not beleive the junk that was in there, rusty water sand almost small rocks. Anyway I beleive these injectors are probably dirty. Does anyone think I may be right? The merc manual recommends only replacement, has anyone ever serviced these? If so, how do you service them? Is it worth taking to the dealer for them to do the pressure drop test? By the way, I have heeded everyones advice about fuelsystem setup. Thanks in advance!
Eric

I would pull the injectors. Be sure to mark them and note which cylinder was rich and lean and send them to have them cleaned and flowed. Try RC engineering for their injector service.

I agree, I would have them cleaned and tested. I would go directly to a place that does it in your area. Don't bother going to the dealer. They will just send them out, and charge you there price after the mark up. Look in the yellow pages for a place near you. Theres a lot of places that service injectors now that everthing uses them;)
If you find there pretty much junk, I have a good complete set of stock injectors, with about 20 hrs on them. I run the 50 lbs injectors with a reprograqmed ECM on my procharged 502.
good luck

Kanookstr,

What programming is done on your ECM? I currently have a Vortech reprogrammed ECM and getting ready to install a Procharger. Yet, Prochager recommended not changing the ECM, so I was planning to go back to a stock ECM with a higher rev-limiter setting. What has your experience been? Also, I was told you don’t need to change injectors until you go up to 7psi, any thoughts??

Thanks

Don't believe everything Procharger tells you!!!!! If you ask that question here you will get a lot of people telling you Procharger, (although they have a great product) there tech department Need some improvements. They use to have a few good guys that new what they were doing, but who knows what happen to them. The stock injectors are running at 95%+ when supercharged, Thats a little to much. Increasing fuel pressure to compensate for boost is really the lazy way of setting up a supercharged engine. It's also less reliable!!!
Arizona Speed and marine has a fantastic program for the procharged 502 MPI engine. I would get the complete upgrade kit for boost application.
You get 50 lbs injectors, 2 Bar map sensor, 120 degree thermostat, and your ECM reprogramed.

I have 200+ hrs sense the upgrade, and it's been running flawlessly!!!:D
Now go do the right thing;) ;) ;)

Thanks for the advice. Now that you mention it I talked to them some time back and they mentioned the kit. I'll give them a call.

Thanks

Kanookstr,
How much do you want for the injectors? I may be better off just buying some good ones vs. trusting that they will be right. Has anyone out there tried the water temperature sensor that procharger sells that compensates with the lower water temperatures? Removing the black crud gets old.

Thanks in advance!