03 Meruiser 350 MPI running hot

[wpowell323]

Engine serial number 0M619908 bravo drive

we have replaced the oring's between the outdrive and gimbal housing, replaced the impeller, replaced the block water pump

seems to run cool at idle, will run for a while at temp and then creeps up to 200 and alarms. the only thing that seems a little abnormal is the sea water housing has a few small grooves on the plate and the housing.

on the trailer when i remove the hose before the power steering cooler the amount of flow seems low to me, but i am not 100 sure what the amount should be or how to measure it.

any help or suggestions would be greatly appreciated!

 

[Lyle29464]

Re: 03 Meruiser 350 MPI running hot

how old are your risers? Are you in salt water? Do you have a closed system? Is the 350 CI model or HP ?

 

[wpowell323]

Re: 03 Meruiser 350 MPI running hot

how old are your risers? Are you in salt water? Do you have a closed system? Is the 350 CI model or HP ?

fresh water, open cooling. It is a 300hp 350 Mag MPI, to my knowledge the manifolds and riser are original. The manifolds and risers are ice cold, the block is what seems to be getting hot, when it alarms I can touch the manifolds and risers and they are not abnormally hot.

 

[Don S]

Re: 03 Meruiser 350 MPI running hot

I see you replaced the engine circulation pump, did you ever test or replace the thermostat?

 

[wpowell323]

Re: 03 Meruiser 350 MPI running hot

we got it fixed. the small grooves in the seawater housing seemed to been letting the pump lose prime. we replaced the housing and it fixed the problem.

 

[Lyle29464]

Re: 03 Meruiser 350 MPI running hot

I need a set of manifolds like that

 

[wpowell323]

03 Meruiser 350 MPI still running hot

03 Meruiser 350 MPI still running hot

I posted the other day, but thought we had it fixed. It is a 2003 Mercruiser 350 Mag MPI. Serial number OM818808 Fresh water open cooling. We have replaced the thermostat, upper drive seals, new sea water pump housing and impeller as well as a new water pump on the block. I have excellent flow at the hose coming into the top of the motor and into block water pump when running. The boat runs at proper temp at idle and you can ride around at 4000 rpm's all day. At WOT the boat will get up to 200 degrees and alarm. If you pull it back from WOT it will quit alarming almost instantly. The compression is dead on 170 every cylinder. I honestly don't know what else to look for or to replace, i hope someone can help.

 

[Don S]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

I have merged your two posts together, since your newest post is nothing more than an update of the problem and your original post has more details in it.
I have noticed you said your drive is a Bravo, but the serial number you have posted is for an Alpha I Gen II. Which do you have ???
Also need the serial number for the Engine. Nothing is listed by year, only SN. Can you also post some pictures of your engine showing where all the cooling hoses are routed on your engine.

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

I have merged your two posts together, since your newest post is nothing more than an update of the problem and your original post has more details in it.
I have noticed you said your drive is a Bravo, but the serial number you have posted is for an Alpha I Gen II. Which do you have ???
Also need the serial number for the Engine. Nothing is listed by year, only SN. Can you also post some pictures of your engine showing where all the cooling hoses are routed on your engine.

the drive is OM162606
motor is hard to read but it looks to be OM616908

 

[Don S]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

What has 0M818808 on it? In your original post it says Bravo drive?

 

[Don S]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

Here is what you need to check. Make sure you have the cooling water hoses that attach to the T with the check balls on them going to the exhaust RISERS. The hoses that go to the bottom of the exhaust MANIFOLDS attach to the the connections below the T.

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

this is the cooling system on my boat, everything appears to be routed correctly..

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=884717&ivar=images/COMMON/1740.png&inbr=8093&bnbr=200&bdesc=Standard+Cooling+System%28Single+and+3+Point+Drain%29

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

nothing has om818808, the motor serial number is hard to read...looking closer it looks to be om616908 on the motor serial number

 

[Don S]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

this is the cooling system on my boat, everything appears to be routed correctly..

http://www.mercruiserparts.com/Show_Pictures3.asp?dnbr=884717&ivar=images/COMMON/1740.png&inbr=8093&bnbr=200&bdesc=Standard+Cooling+System%28Single+and+3+Point+Drain%29

Wonderful, that system doesn't even show up in the parts list for your 0M616908 serial number.

PICTURES........ Need pictures of your setup.

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

I will try to get some pictures for you tomorrow, but that diagram I provided is 100% accurate to my boat..In fact i looked it up using the serial number range that I provided and like I said it matches perfectly to what I have. The serial number on the riser sticker is almost impossible to read, and there is no way to read the block serial number without removing the motor from the boat, so i am guessing at little at the serial number i provided, but as far as the cooling system diagram goes, it is dead on.

 

[Fun Times]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

the drive is OM162606
motor is hard to read but it looks to be OM616908

Let's see if I can help clear up some of the confusion of what engine package we are working with here.

Using the drive serial number OM162606, Your engine serial number should be,

ENG: 0M619908 Model # 4442067RS MERCRUISER 350 MAG BRAVO MPI, Engine Manufacture Date was on 11/20/2002.

DRV: 0M162606 Model # 5231200N1 MERCRUISER BRAVO 1 1.50:1

TRN: 0M564540 Model # 6211001N1 MERCRUISER BRAVO TRANSOM

And the boat I'm guessing should be a 2003 MONTEREY 228 SI, Correct?

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

all of the above info is dead on, now can your crystal ball tell me what my problem is? Let's hope so! Thanks

 

[Don S]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

all of the above info is dead on, now can your crystal ball tell me what my problem is? Let's hope so! Thanks

Working on it.
A neat little trick I learned for looking at things in tight quarters, think digital camera.

 

[wpowell323]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

i looked at the T and the top hoses are going to the risers, bottom hoses to the manifolds. I have enough flow from new sea water pump to shoot water about 1 foot in the air and a full stream at the thermostat housing, the only thing i haven't replaced is the oring between the lower and upper...i inspected it and it looked fine, but i guess it is possible it is sucking air at WOT?

 

[muc]

Re: 03 Meruiser 350 MPI still running hot

Re: 03 Meruiser 350 MPI still running hot

If you think you might be sucking air.
Buy some clear hose and use it to temporary replace the hose between the steering cooler and thermostat housing. If your sucking air you will see it in the hose when you run it.