4.3 Volvo Penta GXI-G engine shutting down

[Cwoodell15]

I have a crazy issue that I can't seem to track down. I've got a 2007 Chaparral 204 with a 4.3 Volvo GXI-G, SX-A outdrive. I only have about 155 hours on her and recently started having a shut down issue. It cranks up great (always has) and once it runs a minute or so, levels out and idles very smoothly. Will also throttle up with no problem. The problem seems to arise when it gets close to operating temp (175 or so). The high pressure fuel pump will start to whine very loudly and gets progressively louder until it shuts off and the engine then proceeds to chug out, like it's starved for fuel.

I have recently done some routine maintenance (idler pulley, tensioner pulley, belts, fuel/water separator, impeller, new battery, etc.) I also bought a new high pressure pump thinking that mine was about to give out.....new pump and old pump do the same thing. I pulled fuel lines and checked that they were clear, vacuum line included, and also pulled the pick up out of the tank to make sure the screen was clean in the tank....and it is. I'm at a loss here and feel that I've checked everything I can think of (or read about). I ordered new exhaust temp sensors as they are visibly falling apart but haven't gotten/installed them yet. Could it be these sensors....or another sensor of some sort? Help! Thanks!

 

[Thalasso]

Re: 4.3 Volvo Penta GXI-G engine shutting down

I think 175 is to hot.Mine 5.0GXI-G runs at 140-145.

 

[Cwoodell15]

Re: 4.3 Volvo Penta GXI-G engine shutting down

You are correct. 175 is middle of the gauge reading, it actually hangs out a notch or so below that.

 

[Walt T]

Re: 4.3 Volvo Penta GXI-G engine shutting down

These are 2 pumps in one I believe, high pressure and low pressure. The 4.3GXi pump has an issue where the interior coating flakes off and ruins the pump. I've taken the assembly apart and cleaned the brass screen. You already have replaced it which makes me think you got flakes still in the system. The fuel injectors will go next due to those flakes. Before you do anything else, get a fuel pressure reading. Pressure regulator may have flakes in it also, down to fuel injectors.
As far as exhaust temp sensors I believe they are to help detect lack of cooling water in the exhaust and may put the engine in engine protection mode. Verify riser temps with a laser heat gun, you may have one blocked. You should replace them if they are crumbling apart as you say. I fear they are like that due to high heat. One of the more knowledgeable guys here will chime in as I'm not real familiar with that system. You can test them with an ohmmeter, the range should be 1700 to 900 according to my alzheimeric memory.

 

[Cwoodell15]

Re: 4.3 Volvo Penta GXI-G engine shutting down

Thanks for that insight! I appreciate any help I can get.

These are 2 pumps in one I believe, high pressure and low pressure. The 4.3GXi pump has an issue where the interior coating flakes off and ruins the pump. I've taken the assembly apart and cleaned the brass screen. You already have replaced it which makes me think you got flakes still in the system. The fuel injectors will go next due to those flakes. Before you do anything else, get a fuel pressure reading. Pressure regulator may have flakes in it also, down to fuel injectors.
As far as exhaust temp sensors I believe they are to help detect lack of cooling water in the exhaust and may put the engine in engine protection mode. Verify riser temps with a laser heat gun, you may have one blocked. You should replace them if they are crumbling apart as you say. I fear they are like that due to high heat. One of the more knowledgeable guys here will chime in as I'm not real familiar with that system. You can test them with an ohmmeter, the range should be 1700 to 900 according to my alzheimeric memory.

 

[jasbo59]

Was this issue ever resolved? Having the same issue with my Volvo 4.3 GXi-G engine on a Four Winns boat with 235hrs.