minimum CCA battery for a 350 mpi
 

shop is telling me a minimum of 850 CCA, my battery is only 500 CCA. Wondering if this can cause my warm engine starting problem. Engine wont start without opening the throttle when warm. I would like it to be turn key, like EFI motors should be. what size battery is everyone running with their Mercruiser 350 mpi?

850CCA is a perfect number. As components wear, resistance goes up. This calls for more amps.

Sounds like you engine has a leaking injector or two. Flooded engine requires you to open the throttle to get it fired. A fuel pressure gauge would get you going in the right direction.

I'd look also at the Idle air control valve. If it stays closed when you want to start it, the engine will get no air. This is a regular problem on those engines. I changed mine this year and now everything is perfect.

Jonathan, I already changed the IAC, and it didn't fix the problem, you think it could be a bad part? is there anyway to check if its good?

Boats in the shop now, took it in yesterday, I sure hope I can get this problem fixed! Next its going to be the starter, from having to start the darn thing repeatedly evry outing! Leaving on Vaca to Banks Lake, Wa on Fri! shop told me no problem having it back by Fri! hope it wasn't just BS. Either way I'm picking it up Fri. afternoon, leaving that night at 10pm

Actually you want to go by MCA not CCA on your batteries ;) MCA is a higher value and the marine reference. So say its a 500CCA that's like 650MCA... Which should be sufficient to start your boat... Unless you start your boat at 0 degrees alot? Hehe

have fun at banks. where you staying? headed to lake roosevelt next week. forecast looks great so far *knock on wood*

Bruce, well be at Steamboat Rock State Park, Site 94, 14th thru 22nd. we prob will tow over to Roosevelt for a day on the river! Thats our usual routine. I'll be in the Yellow Centurion Avy!

Mike, how hard is it to put in new injectors, if thats the case?

Its actually pretty simple. They can be purchased individually, so you can only replace the leaking ones.

Once you determine that the fuel pressure is bleeding off when the pump is shut off, you need to determine whether its bleeding off through the pump, the regulator or the injectors. Since you symptom seems to indicate a flooded engine, thats why I think you may have some leaking injectors.

You can pull the fuel rail off the manifold, leaving the lines intact. Your are only unbolting the rail and then popping the injectors out of the manifold. Then place folded paper towels under the tips of the injectors and energize the pump. This brings the pressure up to operating range. if any leak, they will wet the towels under them.

The easiest way to energize the pump is to pull the fuel pump relay and use a fused jumper across terminals 30 and 87.

sounds like i can do it, I had to replace some injectors in my old caddy once, but that was 15 years ago. Just not sure exactly how to enregize the fuel pump. Where is the relay, and what does it look like, and are you saying the terminals 30 & 87 are on my fuse panel? Sorry so many questions, I’m mechanically inclined, but not that knowledgable about wiring.

I think he is referring to the terminals an icecube style realy. It is a little 3/4x3x4x3/4 box that has 4 or 5 spade terminals. There is a diagram on the side of most ice cube relays so you can figure out which one is which. No ide on where it would be though.

Might look like this:
http://www.wholesalemarine.com/mm5/g...65202T_med.jpg

Or like this
http://www.autohausaz.com/secure/Par...0332209150.jpg

I cant help you on where its located., but I'm willing to bet that it uses the typical "Bosch" style relay terminology: # 30 = B+ (battery) , #87 = load ( pump), #85 = switched side of the relay coil from ECM, and #86 = ground side of coil.

thanks guys! your input has steered me in the right direction anyway, curious to see what the shop finds out. Should get a call from them today.

So what was it??