Raise the idle on a 5.7 mpi
 

Does anyone know if you can raise the idle with a rinda tech mate pro scan tool?

On stock MPI Merc and all other OEM stock MPI engine apps Idle speed is non adjustable. If you are having problems with low idle speed there is a reason for it and or a problem that needs to be addressed .

I've been having trouble with reversion. having slightly higher rpms seems to help keep things dry.

Could probably do it with MEFI burn.

Not if he has ECM 555

So with that said what exactly do you have and your set up along with the ECM

Do you have alpha or Bravo outdrive ?

Too high of idle is an alpha outdrive killer another reason why Mercruiser recommends and keeps idle speeds at the 600 to 700 rpm's.

Was your cam changed in this app

have you pressure tested the exhaust manifolds and riser together ?

What exhaust system do you have here ? Merc OEM dry joint manifold & riser ?

Is your exhaust thru the prop or silent choice or straight out transom ?

A lot more info needed -

Possible need riser extension blocks as your waterline to relation to the boat / exhaust is too high

Have no idea what you have here so throwing out some ideas

If a stock 5.7 is reverting water, you have an issue somewhere else.

Go to your tool box and find your cordless drill, next find the biggest drill bit you have. Drill one hole on the top side of the intake manifold, that should let just enough air in to raise your idle.:party-smiley-004:





Like many have said your idle is set(adjusted) by the ecm thru the IAC motor.

Exhaust manifold or intake gaskets is my 1 and 2 guess

The motor is a bone stock 5.7 mpi 330hp with a new stainless marine exhaust system that is 6in taller and has longer risers made to help stop the reversion. I've been having this problem since day one. I had a thread going on this topic while ago with little success. I had the heads repaired cause of valve seat damage. After a day of running I check the exhaust the port side will be dry but the starboard wet. After I flush the motor both are wet but if I keep the rpms up they're dry.

OEM stock Mercruiser 5.7 MPI does not have a 330 hp. 5.7 - HO mag is 300 hp

It's called SD power pack put out under crusader http://www.michiganmotorz.com/vortec...ine-p-796.html

Well I have to eat my own words here and I have said this before - never assume every question up here is a Mercruiser so with that said about posters not putting all the info and important information asking for help. So if we do not know exactly what you have and all the detailed info posted, how does anyone expect to get quality and correct help. Just saying Like anyone would have known.

Here we go again - I call the Auto parts store - Parts guy - hello - caller - I need a starter - parts guy - whats the application ? caller replys - a chevy - parts guy - good bye - click

Is this is a mefi system you maybe be in luck, that is you can advance the timing to tame the cam down from 600 to 1200 rpm maybe even up to 1500 rpm that is if your cam is reverting, If its a 555 well you have your work cut out for you.

Most likely MEFI 4 - ECM for this app

Pic#7 shows it's a Pleasurecraft Marine engine.
http://www.michiganmotorz.com/vortec...ine-p-796.html

SB - Crusader and PCM are the same company out of South Carolina and for the past year have been owned by Correct Craft Boats. Yes a wakeboard boat company owns these engines companies. Actually that is one way to get you engines into the boat manu's - heck why not own the engines companies to and lets throw them in the boats we make is their moto.

Would it be worth going to dry exhaust. If so what's entailed.

Dry exhaust takes the fun out of boating...unless your boaing is just occassional high speed runs. IMHO.

So, you did not answer - what computer do you have ?

I can deal with the noise I can't deal with the reversion. Sorry it's the 555

There;s a few that can reprogram the 555. I believe Dustin Whipple is one. Can't quickly the remember the other(s)

You better put up a pic of your ECM because crusader nor Indmar nor BARR ever used ECM or PCM 555 (Motorola) never.. You said that you installed a crusader / pcm bobtail engine package. If I recall that package should have came with a ECM already installed. Is that correct or was Mercruiser parts installed to fully dress the crusader package as it did not have an ECM ?

Crusader used MEFI. just saying

[IMG]http://i242.photobucket.com/albums/f...707_202011.jpg[/IMG][IMG]http://i242.photobucket.com/albums/f...707_202207.jpg[/IMG]
Not the best pics but it's all I have on my phone.
How could I convert these risers to dry? Would they have to be sent back to stainless marine?