Cold Start Button on Volvo MD11-C

[My Cyn]

Hi Guys,

Does anyone know if the cold start button on the Volvo MD11-C is supposed to stay down on its own until the engine turns over? The owner's manual is a bit vague.

Bill

[nickzchef]

Mine is a lever, actually there are two...facing towards the stern at the base of the head, inserted actually into the lower valve cover assembly. I have only ever used the rear one (the other is frozen).  I lift up for the colder start, and once started I pull the lever back down.

I hope this helps

Nick

[AnaMeg]

Mine has the button on the fuel pump. It stays down until the throttle is advanced. i.e. If using it, I can not start at part throttle. Cold starting takes a lot of cranking and spits out a lot of grey/white atomized fuel before it starts. The cold start button doesn't seem to make any difference.

Nick, could you be referring to the compression release levers?

Does anyone know any magic for starting a cold MD11c?

Geoff

[nickzchef]

Yes, they are Compression levers. I was told 25 years ago to raise the levers for cold morning starts, and the MD11C starts almost instantly, without fail!

[AnaMeg]

Now I'm puzzled. Not a mechanic so need a bit of education. How can a diesel run if it has no compression? Isn't it the compression that heats the air enough to ignite the fuel? With open compression levers do you turn the engine over a bit and then close the levers when it's spinning fast? But you said one was frozen shut, so are you starting on one cylinder and then bringing in the second?

Which brings up another thought; would it help to turn off the fuel and crank until the engine warms up and then allow fuel in?

Geoff

[My Cyn]

Hi Folks,

After a lot of on-line searching, and some experimentation this past weekend, here is what I learned about the cold-start button on the Volvo Penta MD11C.

The use of the cold-start button is discussed in step 5 on page 5, as well as on page 9 of the instruction book, Publication 3167. The diagram on page 31 shows the button as item 5.
A better view of the button is in the workshop manual for the MD11C, D, MD17C, and D in the top-most photograph on page 33. The spring loaded cold-start button is shown adjacent to item #3 in the photograph.

The key to having the cold start button stay down (engaged) is the position of the throttle.

To engage the cold-start button, while at the helm, advance the throttle to approximately 10% or 20% of full. Go below and press the button down. The button should now stay in the down position. If the button doesn’t stay down, try a little more throttle.

Back at the helm, crank the engine, and you should find, as I did on this cold day, that the engine starts much more quickly. Move the throttle back down to idle, and the button will pop back out.

From what I read, engaging the cold start button allows the control rod inside the fuel injection pump to travel farther, allowing more fuel to be delivered, which facilitates starting. If anyone can elaborate on the internal workings of the fuel injection pump as it relates to the cold-start button, I would appreciate it.

All the best!

Bill

[rbrtfeld]

Good advice here. My MD 11 normally needs the throttle to be all the way full open to engage the Cold Start button. Huge difference when engaged, the motor turns right over when cold. I painted the top of my Cold Start button with Orange Fluorescent paint so you can see it clearly if you have to send someone down to do it manually. Good idea if you need to start the engine in a hurry.

[AnaMeg]

My cold start button will stay engaged only if the throttle/control is at idle. But rbrtfeld, yours needs to be full open to engage. And Bill, you say it should be at 10-20% level. That makes me wonder if my aging brain has reversed my memory. It's been a few years since I sorted this out on my own engine; perhaps I have it all wrong. Nevertheless, when starting, I depress the cold start button with the throttle at low idle and it stays down. It starts a little bit quicker this way but still requires 10 seconds or more of cranking. In May when the shrinkwrap comes off I'll check it out again.

Does anyone know of a source for the remote cold start button control? It's quite a pain to search and reach in the dark every first start of the engine. Maybe rbrtfeld's idea of an orange button will help.

Geoff