Transom Soot
 

Looking for advise, information, fixes, magic, miracles etc, etc.......:mad::(
2003 496 MAG: S/N: OM376502

Went out yesterday for the first time this year and again as last year, the back of the boat was covered in exhaust soot. This stuff is a "B***H" to get off, Acetone seems to be the only way of removal and that just ain't gonna cut it every time out and back on the trailer. Surely there has to be some sort of correction available to fix this problem, heard it was a common problem and that there may have been a recall on it, I don't know that for sure.

Thanks,

Make sure your fuel pressure is between 43-45 with key on motor off. If it low. buy a adjustable regulator. don't go higher either..

Thank you, I'll get a gauge on it this week. I have a bad feeling that this is an on going issue with all 496 motors as the web is loaded with 496 Transom Soot complaints relating to a 555 PCM programming issue. But I'll try anything at this stage.

Supposedly the whipple tune takes care of it. I had the same issue on my old checkmate with the 496. It definitely gets old.

I've already got a email request into Wipple this morning on this very issue as I've read on a few sites that their tune corrects it as you've mentioned, thanks.

What fuel are you running? With the old 502 mags, running premium made it worse.

On another subject.....How is the new steering set up???

Padraig

The early year 555 tunes were richer vs the latter year cals. This seemed to take care of the majority of transom soot complaints. Merc used to update early 555's to the late calibrations but it had to be initiated by a Merc dealer and not the owner straight to Merc. My stock 06 HO tune left a pretty clean transom compared to the pics people have posted. I added the Whipple Stage 2 tune last spring. When running 93oct, there is some transom soot. When running 89oct, virtually nothing over a weekend of boating. Gunk makes a citrus degreaser in a spray bottle that makes short work of the transom soot. Spray on, wait a few mins, wipe off with a wet sponge. I've also heard that the spray bottle tire and wheel cleaners work great also.

87 Octane
The new hydraulic steering is absolutely great, I couldn't be happier with the SeaStar set up, allot easier on the wallet too than the outside steering setups I've priced out !!!!!

Here is a thread that discusses issues related to soot and the 496.
http://www.offshoreonly.com/forums/g...lp-anyway.html

Only running 87 Octane. I've got an email off already to Wipple asking about what they can do for my issue.

This soot is a total bit*h to remove, I've tried:
Wheel cleaner
Bug remover
CLR
Acetone
Hull cleaner
Toilet bowl cleaner
Easy Off oven cleaner
Soft Scrub
Then I ran out of stuff on hand to try...........:rolleyes:

Soft scrub works the best, but hate to have to do that every time I go out, swin platform is a freak'n total mess, but again Soft Scrub does remove it from that too. I've got a product on order that's recommended by The Boeing Company for cleaning jet engine exhaust soot, if that doesn't work, I'm going to paint the entire transom black......:D

We'll see what Wipple has for me in a few days.

Thanks for your input.......:)

Wow, sure great read. I immediately jumped in and pulled my plugs for a read, my issue isn't oil related as the plugs definitely don't show oil burn. Waiting to hear back from Wipple on a possible reflash to address the issue.

Thanks

Simple Green or Spray Nine works well, and much less harmful.

I always have a little bit of soot after long days on the water, but it's manageable.
There was a factory reprogram or PCM replacement, for these motors back in the day.

Call your local dealer with your Engine S/N, and see if anything was ever done to your engine.
If not, you still may be eligible.

+1

My last boat was a 2003 Sonic with twin 496HO's. It also made a ton of soot on the transom. I had the ECM's updated with the latest factory program and the soot was mostly gone. It was something to due with incorrect voltage readings IIRC.

Paint transom. With a painted transom the clear coat makes it much easier to wipe off soot (like a magic erase board). Some will even go black or gray with transom paint. I went white and wipes right off.

Otherwise, the soot gets in the pores of the gel and is a ***** to get cleaned off. Even with Simple Green.

here are the facts in the matter of the 496 one is Mercruiser thru P/A had a field campaign back in 2003 and early 2004 for soot on the transom. Swim platforms made it worse as it held the exhaust in the area no matter how fast you went on the water. (negitive pressure under the swim platform) The deal was to send your PCM 555 in and you would get a recal back with an IAC Muffler taped to the PCM as well. Mercruiser raise the pulsed width modulation of the IAC to allow more air at idle speeds and just off idle until the IAC does not come into play for the air side of it. (jist info) this helped as well for soot among a bit better fuel mapping curve recal into it.

with that said CALL mercruiser with your engine serial number and have all the numbers ready that are on the PCM if needed.. They can tell if the recal was done or not.

Next with that said around 2005 or early 2006 GM changed the intake gaskets to a way better sealing design. the sealing surface was alot better. The earlier ones where wimpy and I strongly recommend changing them to the newer design. This also caused alot more oil consumption ( the first gen intake gaskets did) hence more soot on the transom. Also by the design of the positive crank ventilation not external ( like all others) under the intake area caused oil consumption and soot as well.

I apologize if some one already stated this -

Getting the soot off -- Simple Green -- best stuff ever

Reason for the soot -- I have a 7.4 MIP -- Bravo 3 Captains Call exhaust all stock -- I thought I was doing the engine a favor and put in high octane fuel - the 93?? stuff from the gas station -- WRONG. I had more soot than you could shake a stick at -- I cleaned the transom off -- with Simple Green - put a good coat of wax on and the next fill used plain jane 87 octane -- No soot, no hit runs or errors.

Hope this helps

3pointstar

Rain-x the transom, soot won't stick. That's what i do on the front of boats and enclosed trailers when towing them with my deleted cummins truck, it works great the soot wipes right off

Clean it with vinegar. Apply a quick coat of wax. Next time it should come off easily with soap and water. Then quick wax again. The vinegar cleans the exhaust tips nicely too.

If using vinegar dont forget to re-wax after or the stuff will stick that much worse the next time. a good kitchen soap should get most of the stuff off anything remaining should come off during the wax process. My 02 can get pretty ugly after a day but usually comes right off but the soap will strip the wax as well. Not sure what simple green and some of the other cleaners will do to your gellcoatover time.
I live here in Fresno, Whipple just down the road from my work. I have thought about having them do a stage 2 flash on my boat for some time but its not cheap then stuck running 91 octain fuel. you can also send your ECM to Mercury for an updated flash. i have been told that helps if you have an early tune. Good luck.

I also wonder if longer exhaust tips would help this. There was a post not to long ago with one of the members changing out stock exhaust tips (5 in) i believe for longer ( 10 in ) if not mistaken. Im wondering if the exhaust being further from the boat would help.
For what its worth a very good friend has a 29 fountain (525 blue motor) that is worse than my boat is for soot. I believe the boat is mid 2000 or so.

Here's the story, 2003 motor, ran the serial number on the PCM, there have been "7" upgrades on this model PCM and my serial number had not one of them. Spoke to my Merc Master Tech in S.C. who researched the PCM S/N and he'll get Merc to reflash it to the latest revision. Soooo that being said, it's on it's way to S.C. to be shipped to Merc (thru an authorized dealership). About 2 weeks is what I'm told to turn it around.......I'll report back when its back on the motor and the first time out with the reflash.

I was told the same thing about factory tunes , there have been several tunes after mine.Keep us updated as to turn around time and how the boat runs after. I believe that Whipple is one of if not the only "Authorized" shop to re-flash/program Mercs ECU'S

I finally got a reply back from Dennis @ Whipple on their PCM reflash, Stage 2 = $745, that's allot of coin for soot control and a only 5 to 8% gain in power. I'm gonna look at it this way, Merc's reflash is free, so why not. If I'm still not satisfied the Wipple reflash may have to be done...............time will tell.

I believe they run a little fat to err on the side of reliability. The soot will wipe right off a freshly waxed transom and if it doesn't then vinegar makes fast work of it.

You'll be better off with the latest Merc cal in terms of soot control. Glad to hear Merc taking care of you. I reviewed my Whipple tune in a post on this forum last may if interested to read.

I kinda looked at it this way: Merc reflash=$000.00/ $40.00 shipping; $40.00 out of pocket
Whipple Stage 2: $745 + $40.00 shipping; $785.00 out of pocket

Pretty much a no brain'er for the time being. I'll give your Whipple post a look-see this evening.

Thank you

My engines are also 2003. After I had the reflash done it cleared up at least 80% of the soot. Also only use 87 octane.

Here's the cleaner I ordered, once I get back on the water we'll see how it works. I'll report back in about 2 weeks.

http://i177.photobucket.com/albums/w...psn7ih2alh.jpg

+1.
Wipe off the majority with a towel as soon as you pull the boat out helps a lot also.

Update:

PCM is back after a Mercury Reflash to the current revision for this motor/PCM combination. About a 2 week turnaround for the reflash.

Haven't been on the water since the reinstall, weather has been horrible here. I plugged in my laptop (running the RINDA DIACOM) to the PCM Diagnostic port and found no codes other than the normal "GHOST CODES" for sensors that are not on the motor, this way I know I'm starting out with a clean slate. As soon as I'm able to get out, I'll report back on results of the reflash addressing the "SOOT" problem, as an added benefit I was also told there has been an improvement in the PCM controlled timing on the motor.

Thanks all for sharing your information......:D

That's not bad timing at all. I truly figured longer from Merc. I hear ya on the weather. Our water is all messed up due to the rain season we are in.

Honestly, it's only because I have a close friend who owns a dealership in Greenville S.C. who has lots of high level friends at Merc and can call in a favor when needed otherwise I'm sure I'd still be waiting on it.

This weather is bizarre to say the least, from heavy rains to freezing temps for the overnight, high's in the 50's for awhile.....WTF !!!!!!!!!!!

I'm hot to trot to try out a new BRAVO 1 FS/28P I snatched up recently to keep me off the limiter, but that ain't gonna happen for at least another week at the earliest, so, so depressing.............:(

I feel your pain. I wanted to put the dock in today and it is 36 degrees and high winds. Picking the boat up tomorrow.

Padraig

Update....Now it is SNOWING!!!

I don't know why, but it seems like the weather we used to receive in Minnesota has shifted eastward. We've had some mild winters lately with moderate snowfall and you East Coast guys are always getting nailed.

Not East Coast, far Western NY. West of Buffalo.

Padraig

Some of the retunes for PCM 555 on the 496 was to meet better emissions thru the star ratings and the sticker that are required. Has nothing to do with favors. We have sent them in to Merc as well but not this year nor last year.

Like I said you can call merc with engine serial number(s) and numbers on the PCM from the stickersto see if anything has been done and including on the engine side for warranty work and Service Bulletins.

Last 3 pages (15-17) of this basically what I am talking about meeting the star ratings for emission standards thru EPA and CARB in California, for all marine engines USA sold thru out the years.

https://mercurymarine-gsdesign1.netd...d_warranty.pdf

I have the 500 EFI blue engine in mine with the 555 (2002). Same sooting issues. Had a Procharger on it and the soot was terrible!! Took that **** off and the engine still soots up the transom ( not as bad) . Fuel pressure was lowered but still have the soot. I have to run 91 in it. My question is, does this re cal ( merc) work for the 500 EFI too?? Thanks..

For cleaning the soot, I use a synthetic mothers wax (every time) . I'm just getting tired of waxing this stuff off..

Sorry, I didn't mean to offend. I thought if a state touched the Atlantic, it's East Coast. I'm not implying that you own numerous gold chains and Affliction shirts. :)

I feel for you guys...Of course it isn't Memorial Day yet. It was 85 degrees here yesterday (92 degrees earlier in the week). Spent all day on the water.

Sorry for the Threadjack!! :D


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