warm up time

[cdt785]

Hi. I recently purchased a 1997 boat with a 3.0 mercruiser engine in it. It has a carb. How much time should i let it warm up before I head out with it? When it's warmed up,it runs fine. When it's not warmed up enough, it stalls out when I put it in gear. Also, any ideals about warming it up quicker? Thanks in advance.

 

[boattoy]

Re: warm up time

depends on how busy the ramp is. should run it till you at least get a descent idle.. if the ramp is dead then let it warm up till the gauge reads normal operating temp. WOT will warm it up real quick and make some new friends just as fast. on a more serious note. hold it at 1500 rpm or so(assuming you have shifter that allows you to rev engine without going into gear)

 

[mpdive]

Re: warm up time

You could turn your choke index one turn richer but boattoy really has the best solution. If it stays running in neutral, just let it warm up while you sip your coffee.

 

[Fordiesel69]

Re: warm up time

It is getting colder now, so it is normal to not warm up quick. I warm mine up for about 3-5 min depending on temp. When its in the low 30's out, somtimes I need to warm up longer.

A fisherman I met at the dock is running a 140 deg tstat in his 120HP 2.5L and put a boiler mixing valve into the water supply to the log. This way when the water temp is in the 30's he can keep the manifold warmer while trolling. Also during warmup.

 

[mpdive]

Re: warm up time

Yes it's normal. Cold air is more dense. By closing the choke spring down a tad, it would allow you to leave the dock a bit earlier without driveability problems. If an extra minute or so is not a problem, I would leave it alone.

 

[cdt785]

Re: warm up time

Thank you for all your replys. The boat ramp is pretty empty now,so i can let it warm up longer. During the Summer, the ramp is really busy. I feel like i'm holding boaters up if i let it warm up to long. i'll try it at 1500.

 

[mpdive]

Re: warm up time

I just thought to ask you what your base idle is when it is warmed up. If it is too low, it would be harder to keep it running when cold since the engine needs to burn off the richer mixture. You should be around 700 or so.

 

[QC]

Re: warm up time

From the Merc manual:

4 Place control handle in NEUTRAL.
5 Push THROTTLE ONLY button and position throttle setting as follows:
COLD ENGINE - Move control/throttle lever to full throttle, then return to about 1/4 throttle. In extreme cold it may be necessary to pump lever more than once.
WARM ENGINE - Move control/throttle lever to 1/4 throttle position.
FLOODED ENGINE - Move control/throttle lever to full throttle. Be prepared to decrease engine speed to
1000-1500 rpm as soon as engine starts.
6 Turn ignition key to START. Release key when engine starts and allow switch to return to RUN position.
7 Carbureted Engines - Move control/throttle lever back to decrease engine rpm to 1000-1500 rpm if necessary.
8 Check oil pressure gauge immediately after engine starts. If oil pressure is not within specified range (see SPECIFICATIONS), stop engine immediately and determine cause.
9 If engine is cold, run engine for 1 or 2 minutes at fast idle (1000-1500 rpm).

 

[cdt785]

Re: warm up time

Thank you all for your advice.