250xb tuner

[stratospro]

I have a 03 250xb and hear people talk about the good sound of these motors, mine sounds no different than my old 200efi, was thanking about getting a new tuner but was wondering if tuner may be clogged? Does anyone know if this could be the problem or if i just have a quite 250xb. THANKS for any info.

[low slung cruiser]

that motor should do alot of "CAM-ing" when at a 800 rpm idle...
never heard a 225 efi or 250 xb that didn't...

[kllr bee]

You are probably running it lower down in the water than some do. Make sure when you are idling that the hole on back of motor by the pee tube is above water.
Richard

[CRIMSONGAMBLER]

Some times mine sounds like a opti and then sometimes it shakes the boat, depends on what kind of mood it's in.

[EuropeanAM]

What's your engine's serial number? Depending on the type of tuner you have (that's why serial number is important), there may be a relatively simple "visual check" you can perform....

[stratospro]

serial number OT652514

[EuropeanAM]

Remove gearcase.

Look up through exhaust portion of driveshaft housing. You should be able to see TWO rectangular shaped exhaust ports (bell shaped with slight height offset).

FORWARD of these two ports, you should be able to view SIX (6) small holes (these are idle relief ports). The diameter of these openings should be 3/8" (yours may be substantially clogged with carbon). You are viewing only SIX of the EIGHTEEN (yes 18) port openings.

If yours are blocked or clogged with carbon, see the following post:

http://www.bbcboards.net/mercury-3-l...ust-tuner.html

[tmbullet]

I have a 2004 225 EFI and it's not real loud , but it sounds mean as hell, sounds like it has a big cam in it... love it.......

[stratospro]

Thanks for the info, I will check and see if i can tell if there is a carbon build up, Also will this effect the top end performance or just idle ? THANKS

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by stratospro &raquo;</td></tr><tr><td class="quote">Thanks for the info, I will check and see if i can tell if there is a carbon build up, Also will this effect the top end performance or just idle ? THANKS</td></tr></table>

It will affect BOTH to some degree (depending on severity).

[jughead101]

a little off topic but can i ask what kind of water pressure do you guys have on ur xb's ?
mine seems to be a little low. thanks.

[Stanford]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by jughead101 &raquo;</td></tr><tr><td class="quote">a little off topic but can i ask what kind of water pressure do you guys have on ur xb's ?
mine seems to be a little low. thanks.</td></tr></table>

Mine seems to be around 11 to 13 at WOT. It seemed low to me but had several people tell me these motors were high volume/low pressure and that it was fine as long as it didn't get below 8 or 9 lbs. But you might want to ask Don to be sure.

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by jughead101 &raquo;</td></tr><tr><td class="quote">a little off topic but can i ask what kind of water pressure do you guys have on ur xb's ?
mine seems to be a little low. thanks.</td></tr></table>

Depends on which gearcase you're running.

<u>ALL 3L Models</u>:

At idle speed: 1-3 psi

<u>Models WITHOUT low water pickups</u>:

8-12 psi @ WOT

<u>Models WITH low water pickups</u>:

15 psi MINIMUM @ WOT (prefer to see 18+ for safe measure in turns)

<u>Keep these figures in mind when changing gearcases on 3L models. A low-water pickup gearcase CAN be added to an earlier model- but NOT vise-versa, as doing so can actually result in overheating and "faults" due to INADEQUATE WATER PRESSURE</u>.

[jughead101]

looks like i am ok, just seemed a bit low.
thanks guys !

[runninrusty]

I have a 97 225 EFI and a friend of mine has a 01 225 EFI and ours sound totally different. His sounds like it has a growl to it and mine is alot smoother sounding. It os the year that makes the difference????

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by runninrusty &raquo;</td></tr><tr><td class="quote">I have a 97 225 EFI and a friend of mine has a 01 225 EFI and ours sound totally different. His sounds like it has a growl to it and mine is alot smoother sounding. It os the year that makes the difference????</td></tr></table>

SERIAL NUMBER is the key. There was a change to the tuner (earlier model tuner was much smaller).

[runninrusty]

97225 EFI OG486942

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by runninrusty &raquo;</td></tr><tr><td class="quote">97225 EFI OG486942</td></tr></table>

Yours SHOULD have the larger/later-style tuner.

It's possible that your buddy's has been modified.... or that his is substantially CLEANER than yours (more likely the case).

Take a look at the following post for info:

http://www.bbcboards.net/zerothread?id=637339