For some reason this thread will not let me "like" your post but Thank You. The shot does have a cool look to it

as of today FST filters do not install to the OEM Merc mount --- Black production side nor any Volvo s. Also will not install to some of the Merc racing engines either.

If room allows the biggest filter the better but quality depending.

Racor is a good filter but not cheap priced either.

Reload or refresh the page. Then you can do it.

Faster than OSO Tech huh ? LOL.

Straight out of the shipping box --- 496 injectors always need to be check out and service. NO BS these more times than not really need to be deep cleaned --- https://cimg1.ibsrv.net/gimg/www.off...77b067908f.jpg
https://cimg0.ibsrv.net/gimg/www.off...ad5e25e41b.jpg
https://cimg5.ibsrv.net/gimg/www.off...17bc36d163.jpg
tested and flow tested - --- so very common as they suffer from many contaminates - he is one of them. Straight out of the box - 2008 app not that many hours

would you say the contamination in that injector would be from the ethanol content in the fuel, and fuel /water contamination to turn it that yellow/brownish color?

if there was no water contamination i would suspect thet the ethanol would just leave white deposits correct ?

That set of 8 had rust thru out the cool fuel and alot of rust internally in the fuel rail. Water intrusion and it sat around for X AMOUNT of time. That was not from E 10 because the other engine was not like this period nor experienced the loss of 300 rpms. .

to further expand -- alot in the issues at hand cause injectors to end up contaminated internally all way thru the injector itself. .

Lack of maintenance

Lack of fuel maintenance

improper lay up for seasonal storage and or winterization.

water in the fuel and E 10 is NOT the main source of water intrusion

poor quality - some of these marine parts. ie: fuel rails , cool fuels, seals on top of the gas tanks, gas caps themselves, fuel lines, fuel pumps, fuel filters and so on.

496 injectors suffer from contamination -- so hard for them NOT to. I prob have 1000s of pics -- 496 injectors and most are in need of deep cleaning and flow testing beforehand.. Marine injectors suffer by far worse than ANY auto side injectors. BY FAR. - freaking junk yard auto injectors can be in better shape than alot of marine injectors sitting in owners garages.

BUP can you test this type of injector? I dont believe they have a screen or do they?https://cimg8.ibsrv.net/gimg/www.off...90b52505e2.jpg
https://cimg1.ibsrv.net/gimg/www.off...3575ae98a1.jpg

tried to send you a pm,

YES I can. Any gas side injector I can test EXCEPT the Etec injectors. They require 50 Volts to do so and at steady state. But soon I will be able to test all Etec injectors. For those whom do not know etec that is Johnson and Evenrude outboards systems / engine and injectors.

I can TEST and clean all marine MPI and GDI and DI injectors for outboards, auto, truck, natural gas, jet ski, marine I/O and inboard. Even Merc Opti max - and Yamaha HPDI.

Also the 8.2 Mercruiser Cat engine and that requires special attention. Those injectors a person can really jack them up. And those are not cheap to buy period.

I do have alot to say about your injectors. for starters they become restricted flow in patterns and flow volumes.

VoodooRob as he has basically the same injectors. He knows what I had to do to make all that flow very very well again.

I will post more info about them. THANKS for asking as well.

Here is some of the jist but there is more as to why these really need to be tested and CLEANED. NO BS. I have to find some of the parts here to post what Im talking about.

i tried to send you a PM but your box is full. Any other way to contact you?

Since your post to current I have tested 8 sets of these from people all over. Common issue with these I can go over with whomever about that info.

Can a dirty or leaky injector cause a miss at idle, cold, that clears up once the engine gets some heat in it? I picked up a dead miss late last season when the boat is cold right at startup. By the time I've idled out from my slip past the break wall/No Wake out of the marina it picks the cylinder back up and runs on all 8 the rest of the day. No codes and plugs only have 50 hours. 496 MAG. Just curious. Was going to toss a set of NGK TR55IX's at it to replace the AC 41-983's but engine always ran great on the AC's before. First thought was spark plug but then got to thinking maybe something is fouling it or it isn't getting fuel at first. Thanks.

I WOULD look at all ignition stuff on the engine. Clean flame arrestor -- good working IAC - and all those IAC system related areas & parts, also fuel pressure testing inwhich can determine a leaking injector. Added in the mix of course a scan to see all parameters. Parameters of inputs and outputs are important as well and I understand if many do not know what they should be.. There is alot more to scanning an engine - just because it does not show any fault codes means nothing. Scanning does not show fuel pressure, nor any part of fueling nor its fuel delivery. Just saying

With that said ---- At some point in time injectors needs testing & servicing. Its like a carb engine at some point the marine carb needs to be cleaned and rebuilt with a new kit. Carbs and fuel injectors are both fuel delivery items - just that many people NEVER think about the injectors and maintain so they do not become contaminated. Fuel injectors always become contaminated in marine apps -- even well maintain engines and maintained fuel systems still see fuel injector contamination. At some point in time the orings need to be changed on fuel injectors as well. .

I would change the spark plugs first - The NGK plugs are better to use - leave the gap alone unless it is screwed straight out of the box. Look at all 8 to see if the gap matches and good straight alignment with the ground strap

Next move on to testing plug wires and then coils, to make sure all that is good to go as well.

I thought I’d share my experience so far with the 496 fuel injection system. My boat was not performing very well at the beginning of last season. The first outing it did “okay” and on the second, would barely get up on a plane. I started troubleshooting and found a lot of reference to fouled plugs causing similar problems on other 496’s.

I changed all 8 plugs which were in pretty bad shape, thinking that the problem was solved (But why did they foul?). Took the boat out again and it ran much better, but still was down a few hundred RPM at top end. Things were still not quite right.

I thought this would be the perfect time to purchase the Rinda scan software and see what was going on! The results were inconclusive (to me). No abnormal codes. Things seemed to be in spec. Then I ran the “Induced Misfire Test”, which commands the PCM to disable the fuel injector on a selected cylinder. If the RPM changes when the injector is disabled, you know a problems exists there. I noticed that on some cylinders the RPMs barely dropped or didn’t drop at all. There had to be a fuel delivery problem.

I ended up on the OSO forums reading about all of the problems with clogged injectors on the 496. Especially on the years that had the Cool Fuel III systems. This system was painted on the inside by the factory. The paint degrades and then starts peeling off and getting into the injectors.

I saw that a lot of people were talking about BUP and his injector cleaning service. He had stellar reviews so I contacted him. He has been beyond helpful in educating me on all of the intricacies on this fuel system! He gave me step by step instructions for everything I need to do for removal, including other things to look for. He has been a great communicator and is passionate about what he does. I just sent the injectors and fuel rail to him for inspection / repair and am excited to see what he comes up with and get back on the water this spring!

I also learned that a missing injector pintle cap that is sitting on top of the intake valve CAN be removed through the injector port without removing the intake manifold. But that’s a whole other story!

I will update as things progress.

Good choice. BUP is the best. Well worth the time and $$ having them done.

I plan to pull my injectors and send BUP's way as soon as the weather breaks. Although my engine was rebuilt a couple years ago and I specifically asked the builder to clean/test the injectors I received no paperwork on who did it or the results. Better safe than sorry.

Thanks GUYS for all the comments - Somefun sent me one pic of his injector and just by him turning the injector upside down BLACK PAINT was coming out of the injector.

Also good talking to Somefun and we will have more conversations when I get all of your stuff in my hands,

In the meantime for whomever if you want to call and talk about boat related stuff thats fine as well. I can try to help out my best if you have questions. Basically all my experience is from Merc racing 700 sci and down and ALL black side Mercruiser production engines.

Other experience is 10 to 15 percent is custom built marine engines in the mix. Also Volvo Penta, Indmar including their Raptor marine engines and PCM marine engines. I also have worked on ILmor V10 and LS marine engines, Innovation Marine, Marine Power, Commander, OMC sterndrives, Lexus / Toyota Marine engines among others. .

My number is listed and is on my website. Heck some of guys, we have talked for hours on the phone about their boat and other boating related topics. My better half says I am worse than a women talking about soap operas all day long, just my conversations is all about boats..

Thanks again

500 EFI injectors
 

Good stuff! I have also heard good things about BUP, super nice guy.

I have been sending my injectors to "Arcticfriends" Steve Smith, Smittys Eng & Trans - Transmission Repair, Automotive Engine, for years. All my friends have had good luck with him also. Plus he just got a brand new machine!

Funny how maintaining fuel systems gets neglected sometimes. Same with carburetors, people complain about carbs but haven't done a $29 rebuild kit in 10 years and wonder why they have trouble! LOL!

Here's the follow up to the original post:

Finally installed the injectors and got out on the water yesterday. What a HUGE improvement! The boat gets on plane much faster and top-end is 5 mph faster! That's quite an improvement for a 50 mph boat! I can't say enough about BUP, his workmanship and attention to detail! He's committed to getting you back on - and keeping you on - the water! Best customer service I have ever experienced! Thank you!

At any given point injectors can become dirty or water (condensation) sat in the injectors. The best thing to do is fuel samples and cut open fuel filters. As I mentioned - injectors are a fuel delivery item just like a carb - sitting with fuel in carb for months or years on end will always need a carb overhaul and cleaned very well however. The same goes for injectors but here is the kicker- a carb is ONLY a mechanical fuel delivery item with zero electrical issues and basically not many moving parts at all.

Fuel injectors are mechanical and electrical fuel delivery item so you can have the electrical side as an issue on top of. Here is another kicker - internally of a fuel injector there is a pintle and seat or a ball and seat - the pintle lifts off the seat per commands thru the ecm basically a short jist how it works - but did you know that pintle or ball can move (lift and close off the seat) about 100,000 times within an hour - think about that. Anyways fuel injectors really need to be looked at as a maintenance item in a boat plus they suffer from heat soak in marine apps way more than any auto / car ever would. No air hitting the engine - no fans blowing ever especially when the engine is shut off.

BUP - that post (#64) should be the first thing OSO has come up or has a person read before starting a thread as to why their boat isn't running right. Most of the boats are getting older and the injector gremlins are showing up

Plain English and vivid enough anyone with no technical knowledge can grasp injector service is a necessity (and not an injector cleaner/ Sea foam fix)

Totally agree, I have worked with BUP with our boats injectors and its really a huge difference once you have the injectors serviced. A well maintained fuel system and ignition system goes a long ways for smooth idling and top performance. I also have a complete new ignition system from BUP and that made a huge difference at start-up and idle even AFTER the injectors were restored to 100%. These boats are getting older and people are throwing hp adders at them, modifying exhaust and not going thru the simple stuff like fuel and ignition systems.

Where is your info listed so I can send my 496 injectors to?

check your messages...

Hope you get a commission. Lol.

I wish, but my guess already had 50 other message's with same suggestion