Cold starting 2gm20f doesnt start as easy

[Jared1048]

Hi,

This will be my 2nd winter with the boat and its taking 5-10 seconds to start this winter when last it would take after about 5 seconds. Its also got a new development this year in that it feels like its starting to fire every second or two (Very slow) and dies. This repeats a couple times until i can get it to fire up. My starting sequence is full throttle for a couple seconds, 2-3 times then close sea cock, then 2-3 times more. My batteries are fully charged with a (440 ah banks pusing behind it) and im staying on the boat this winter so its not bone cold (55-60 degrees in the engine compartment).

A buddy was talking about outfitting his diesel with glow plugs and that made a world of difference. I'm going to try opening the hatch and letting some of the warm air get to it before I try again but I'm a little worried that "something" is deteriorating. Engine has 1200 hours with the last 500 being from me.

Any ideas to what could be going on?


Thanks!
-Jared

 

[Bill Roosa]

diesels use compression to heat the air and cause ignition
cold air and a cold engine WILL require the motor to be cranked more to get the cylinder walls "hot" and ignition to commence.
This is normal

 

[Steve Dion]

I doubt it as cold last winter. I would think that 15 seconds is not too bad.

If you are cranking any longer you should be sure that the thru hull is closed so you do not flood the engine.

 

[anchorclanker]

whenever there is a question like this, a compression test should be done before further speculation, as without it, all anyone can ever do is guess. You didnt mention the last time the engine had any maintenance, or a tune up.

 

[Jared1048]

I'll look into doing a compression check or paying someone as I've never done one before or have tools.

I’ve been doing all the maintenance myself and change the oil, fuel and air filters sooner than recommended. I do need get the injectors cleaned\adjusted for the scheduled 1000 hours mark that I haven’t done yet.

Thinking about it though there is a new development over last year and that’s come up. I’ve noticed more oily residue on the block. I'm pretty good at keeping it clean to spot where it’s coming from but haven’t pin pointed it yet. I did notice that the dip stick is a little loose and ordered a new one thinking that oil might be dripping out of it on a hard beat.

 

[Warren Milberg]

Yanmars are notoriously cold hearted beasts. A couple of thoughts as I have the same engine. Whenever it gets cold here, I use a hair dryer up against the air intake to fool the engine into thinking its summer. Sucking in warm air really helps when starting. Also, this engine requires fuel with a cetane rating of 45. Most commercial outlets are selling diesel with only a 40 cetane rating. If this is your case, make sure you have very fresh fuel with a cetane booster added.

 

[kloudie1]

Maybe a block heater:
http://www.griggslawnandtractor.com/servlet/the-1194/Kats-Magnetic-Block-Heater/Detail
if ya have the room..

 

[Ralph Johnstone]

Not Necessarily the Answer ...........................

.................. but maybe a solution.

I have a somewhat similar problem with my lawnmower engine (aka. 2GM20F) and it's after the engine hasn't been run for about three or more days. Not as much hesitation as you have but still takes a few seconds to catch.

However, if I start it within 1-2 days of it's last running, I swear it starts within 1/2 a revolution. And this is with the engine stone cold on a fall morning. The oil which is still in the rings is causing a good seal on the cylinder walls and good compression.

You might try flipping the unloaders on the engine and spinning the engine for a few seconds to raise the oil pressure enough to wet the rings. Make sure the fuel stop is pulled and it's always nice to keep the raw water cooling valve shut at this time. Once that's done, put everybody back to normal position and see if it starts any easier.

 

[seadaddler]

mixing elbo

Many years back aftering cleaning out the mixing elbo the same engine in my Hunter 290,it would start so easy and ran so much better.
I took the mixing elbo apart aand cleaned it out real good and it started much better and the engine ran much better also with way better motoring.
it so much cheaper to give it a shot aand ccheck it out just 4 bolts and hose clamps and it is off,I had a marine shop take it apart and new gasket.
Nick

 

[Benny17441]

One variable to consider is the oil grade being used. A thicker oil will slow down cranking speed needed to compress and ignite an adequate volume of fuel mixture.

 

[anchorclanker]

Providing you don't have a fuel issue.... Running a diesel at low speeds, or idling for long periods can lead to carbon glazing the cylinders. You now are saying the engine is getting oily and the dip stick was coming out, all are signs of increased blowby due to loss of compression.

As you say, the engine ran okay originally. I would simply ask how you have been running it, what kind of oil, have you been changing it, is the engine in a good state of tune, etc..

If the cause is indeed carbon fouling, many diesels have come back to life after a tune up and running at full power to clear the carbon. Some MMO (1/2 quart at least) in the oil will help too.

 

[Stretch]

My first leak on the Yanmar was the back of the oil pan those 2 nuts at the back. I used fabric softener to clean up and take away the odour, a trick picked up here on SBO.

I think you answered your own post with the injectors, worked really well for me with an older low hr engine. Pitted injector and low idle pressure, they told me.

Other posts are spot on. Read another post that suggested wd40 as starter fluid but hairdryer is my fav too.

 

[Neil McDonald]

Try running your hand around the fuel supply system to check for wetness indicating a fuel leak. Over time even a minor leak also lets air into the fuel system which prevents the injectors giving the cylinders a full shot of fuel each time. The banjo joint on the secondary fuel filter mounted on the engine is a weak spot prone to leaks. When I fixed my small leak starting problems went away.

 

[anchorclanker]

Read another post that suggested wd40 as starter fluid.

I would strongly suggest everyone avoid any kind of starting fluid on any kind of diesel.

Diesels are compression - ignition engines. They initiate the combustion of fuel by the temperature of the compressed air. Fuel is timed to be injected near top dead center where it is able to then "push" the piston downward as the crankshaft passes over the top. There is no spark plug. During cranking, compression can raise the temperature of the air in the cylinder over 500F. More than enough to ignite any fuel.

When a fuel is added to the incoming air supply, there is no control over ignition timing. As all fuels have particular flash points, some will detonate at lower temperatures than others. If a fuel detonates too early, while the piston is only part way to the top for example, the pressures can greatly exceed the design strength of the various engine parts. Strong detonations can break rings, blow head gaskets, even bend a rod. Higher compression diesels, such as those with prechambers (indirect injection), can have compression ratios above 22:1, producing temperatures exceeding 1000F, and will detonate ingested fuels much sooner than direct injections diesels.

It is because of these facts, and damage that has been physically seen by mechanics, that starting fluids are often referred to as a drug. That once a diesel has sustained some broken rings from starting fluids, it can no longer start without starting fluid as it simply doesn't have the compression required to do so. And it is not isolated only to indirect diesels, but all diesels can be damaged by its use.

Back in the late 80's and early 90's, IH Case, among others, offered Ether starting systems on their heavy equipment. It cost them so many engines they not only stopped offering it, but removed the systems from older machines to prevent engine damage. Just dont use it, and pass the word to friends to stop using it. And were talking WD-40 as well as hairspray or anything else. A diesel with good compression, a strong starting system, and in tune, will start on its own at pretty cold temps. If not, there are block heaters and the like that can be used to get some heat into them to get them going. But starting fluid should just be forgotten.

 

[Stretch]

Thanks Anchorclanker, my dad the mechanic always hated starting fluids, in gas engines and even gas line antifreeze. I will save the wd40 for salmon fishing lures...

 

[Jared1048]

Thanks Anchorclanker, my dad the mechanic always hated starting fluids, in gas engines and even gas line antifreeze. I will save the wd40 for salmon fishing lures...

yeah, I agree. There is something wrong if it requires this much effort to get going.

thanks all for the good info! I've got something to go on

 

[Steve Dion]

Yanmars are notoriously cold hearted beasts. A couple of thoughts as I have the same engine. Whenever it gets cold here, I use a hair dryer up against the air intake to fool the engine into thinking its summer. Sucking in warm air really helps when starting. Also, this engine requires fuel with a cetane rating of 45. Most commercial outlets are selling diesel with only a 40 cetane rating. If this is your case, make sure you have very fresh fuel with a cetane booster added.

I am with Warren on this. Try the hair dryer to see if heating up the air intake does not help. I would not worry about this until the weather warms up and see how it does. If you still have the issue with the dryer or warmer weather then you may have a problem.

 

[Jared1048]

so I ran a test last night. This time before I went to bed (on boat) I opened up the engine compartment stairway/cover to let the warm air circulate around engine and faced space heater toward engine and left it running all night. In the morning I started the motor and it kicked off instantly! Its never started so easily on the initial start after sitting for a week. Very happy

Jared