Tricks on starting an old Perkins when cold

[NSboatman]

hey story-

I'm not sure what you mean when you say you checked your battery with an ammeter and it has the punch. Unless it's a clamp on ammeter and you're checking current draw while cranking, and comparing this to voltage on the terminals while cranking.

really, there's been a lot of very good info on this thread already on the subject.

If you have a heater in the engine compartment, and a pan heater on the engine, and you say your batt has the punch and it still won't start, then you've got other issues.

4-108's are about the most basic engine there is. if you can spin them fast enough, give them atomized fuel at the right time, and have even half decent compression in 2 or 3 of the 4 cylinders, then they will run.

Keeping them running is nearly as basic too.

Do you have the flamestart feature on this engine? if not, get it. that will work every time if it is setup properly, which is dead simple to do.

I suspect - just a hunch - that you're not getting your mill to spin fast enough when starting cold. at low starting speeds, fuel delivery is meager at best, and it only takes a little bit of out-of-tolerance crap in the fuel system to add up to not enough atomized fuel being delivered. this is also common withe the HP fuel pumps on the 4-108's - at low rpm (like when starting). you really need to give them a couple of good spins to get compression and fuel delivery up. try the decompression trick - I bet it works.

and check your starter wiring. I bet you've got more losses there than you think. almost everyone does.

good luck!

[storyinframes]

Originally Posted by NSboatman

hey story-

I'm not sure what you mean when you say you checked your battery with an ammeter and it has the punch. Unless it's a clamp on ammeter and you're checking current draw while cranking, and comparing this to voltage on the terminals while cranking.

really, there's been a lot of very good info on this thread already on the subject.

If you have a heater in the engine compartment, and a pan heater on the engine, and you say your batt has the punch and it still won't start, then you've got other issues.

4-108's are about the most basic engine there is. if you can spin them fast enough, give them atomized fuel at the right time, and have even half decent compression in 2 or 3 of the 4 cylinders, then they will run.

Keeping them running is nearly as basic too.

Do you have the flamestart feature on this engine? if not, get it. that will work every time if it is setup properly, which is dead simple to do.

I suspect - just a hunch - that you're not getting your mill to spin fast enough when starting cold. at low starting speeds, fuel delivery is meager at best, and it only takes a little bit of out-of-tolerance crap in the fuel system to add up to not enough atomized fuel being delivered. this is also common withe the HP fuel pumps on the 4-108's - at low rpm (like when starting). you really need to give them a couple of good spins to get compression and fuel delivery up. try the decompression trick - I bet it works.

and check your starter wiring. I bet you've got more losses there than you think. almost everyone does.

good luck!

NSboatman,

thanks for some diff insight into this starting problem.

Its been very cold here in Virginia and i am stuck here for engine probs.
I want to head south through ICW.

1) i thought the issue was with my battery. I got it examined by a mechanic. he says the battery is good.
2) The engine does start on warmer days though with some vapours of gasoline on the intake. Its too cold now and maybe you are right fuel injection could be an issue.
3) i will also check the starter wiring.
4) can I get a flamestarter at a NAPA outlet?

Got to get this damn thing going.

thanks

[NSboatman]

nope, I don't think you can get the flamestart from Napa. it's a 'custom' perkins part (but i'm sure it's made by someone else - I just don't know who). TAD diesels sells I think, probably on fleabay as well.

It's essentially a glow plug and a length of fuel line (pipe) with some fittings and a thermally controlled valve. it gets installed in the air intake manifold, right under the intake cap.

The fuel line (a small length of hard fuel tubing) runs from the fuel filter block on the engine, and gets charged at low pressure with fuel when the engine is running.

The next time you go to start it, first you hit the glow plug button (you'll have to install this and wire it to your battery/12vdc - use a fuse and wire capable of slightly more than 20 A - 25-30 should do).

When the glow plug reaches temp, the thermally controlled valve opens and dumps the contents of the tube (an ounce or so of fuel) onto the red-hot end of the glow plug, and of course it ignites, essentially lighting a small fire in your air intake. usually takes 4-6 seconds to get 'ignition'.

then you hit the starter; the burning flame gets sucked into the cylinders and pre-heats, and helps initial firing along.

primitive? Yup. so is the rest of the engine, but it works.

The flamestart is the "OEM" solution to cold weather starting on the 4-108.

If I were you, I'd try the decompression trick with your engine. Take the cover off the air intake (it usually is pretty loosely clamped there), and cover the intake port with your palm, get a good seal. hit the starter, and the engine will crank -trying to suck your hand in. it will crank really quite quickly - like nearly twice the speed of a normal crank (because you are creating a vacuum in the cylinders that is helping)- but won't fire until you remove your hand and give it air for compression.

I've found this little trick works really well on marginal perkins engines - 4-108's especially. it gets the HP pump spinning much faster, which gives better fuel delivery to the injectors, so you get better fuel atomization right when you need it. Spinning faster also heats the engine up better internally, gets you better oil pressure and therefore better lubrication on startup; and it actually reduces the load on the starter momentarily while you keep it partially decompressed. good for batts that are nearly dead or starters that are on their last legs.

you will end up with a little black ring of soot on your palm, and a red hickey in the middle where the engine tried to suck out your blood... but it goes away fast

...a little shot of WD40 into the manifold before you decompress it never hurts either.

wait - did you say it needs gasoline vapors to start when its warm too? that ain't right.

if that's the case, and it's spinning fast enough when trying to start, you've either got poor compression or poor fuel delivery. check compression (with a gauge in the injector ports). could be worn or busted rings. since you will have the injectors out to do this, then get them serviced. and hell, if you're going to an injector shop, take the HP pump to them too and get that checked out.

good luck-

bg

[storyinframes]

Brilliant explanation NSboatman,

let me try some of these tricks tomorrow before i go to the injector stage.

regards

[Sailmonkey]

Frames----
You used to use ether? How much? I don't worry about ether washing the oil from the cylinder walls as has been mentioned here time and time again. IMHO the big problem with ether is the explosion it creates. Diesel burns (relatively) slowly whereas ether explodes....this explosion causes ring damage, just one crack in the top piston ring can cause an engine to lose enough compression to be hard to start, but run fine once running.


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[NSboatman]

Fully agree with Sailmonkey - You'd have to use one hell of a lot of ether to wash the oil off the cylinder walls, and it evaporates very rapidly. It is the explosion that happens in the cylinder that is the issue. Since it so much more volatile, it can even explode before the piston reaches top dead center, and shock loads the hell out of everything in the engine. Ring cracking is common - which is why some folks talk about engines becoming "addicted" to starting fluid. in reality, the violent explosions from using ether create ring or other damage which further reduces the available compression ons tartup, which makes the engine even harder to start without ether - hence the impression of becoming "addicted".

I'll say it again... WD40 instead of ether!!!! works a treat.

bg

[Aikiguy]

Cold start from parts manual

[Presto]

When I replied to all that we use a hair dryer to heat our Perkins 4-154 during the winter, I failed to mention that we remove the breather and point hair dryer down the intake for a couple of minutes and it fires right up. If the wife is aboard she puts hairdryer in intake while I crank and it starts immediately. Engine is in a 1980 CSY 44 walk thru. Has been a great engine for us.

[IdoraKeeper]

Seems like you could just start it more often. If you can. That way it stays all primed up and the injectors keep a better spray pattern right away. Once the mixture is out of limits you have to crank enough to clear it out and re establish proper fuel air ratio. My Yanmar is always hard starting after winter but after the first run is good to go.

[Cadence]

Originally Posted by storyinframes

I also have a Perkins 4.108 on my westsail32. Its been pretty cold here on Chesapeake. temps dipping to minus 16C.

My perkins would start sometimes when it is sunny.

I stopped using Ether.
I got my battery checked with an ammeter and it has the punch.
I installed the magnetic 110AC heater under the sump. And a blower heater in the engine compartment.
Still the engine wouldn't start.

It did start yesterday though. and once warm, the engine starts in half a turn of key.

How more better i can heat up the engine. today is 20F/-7C

You can do it "more better" by moving south. This year I'm not sure how far.

[Cheechako]

Have you guys considered one of these? They heat an engine compartment pretty well and only pull electricity like a 150 watt bulb..

[storyinframes]

@NSboatman

The engine started without much issues.
It took 5-6 cranks and then it roared into life.
I did spray some silicon based spray as all the water around the boat is iced. 8" of ice.
Kept the oil sump warm throughout the night.
Directed a 1000W air heater into the intake while giving starts. The blower is pretty hot.
in addition, I heated other parts of the engine with the heater for 20 min before i started turning the key.

Just realised my previous owners had got done 1500 $ job on the injectors and pistons last year.

But it was a relatively warm day today. There is going to 6"-8" of snow tonight. so tomorrow is going to be cold again. So i will check again tomorrow.

I keep in mind all your tricks and what others have mentioned. Its in my little diary.

thanks for all the support

[bletso]

Originally Posted by Cheechako

Have you guys considered one of these? They heat an engine compartment pretty well and only pull electricity like a 150 watt bulb..

What are they? I can't remember ever seeing something similar.

[Sailmonkey]

Originally Posted by bletso

What are they? I can't remember ever seeing something similar.

It's nothing other than a 100-150 watt heating element in a fancy plastic cover. A light bulb will do the same thing with the added benefit of light.


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[BruM]

What does silicone spray have to do with starting the engine?????