Cold Starts

[Burty]

Hiya

Just a wee query - my 1995 3.1 MU has ben starting without a hint of concern or apprehension for the past year but recently the battery lingering so I replaced it as it was taking a while to fire after turning over sluggishly. As I live in Christchurch and we have had some pretty cold mornings these past weeks Im not surprised that its been taking a bit of effort to get things cooking in the am. However, now Im finding that things are a bit sluggish to get started every morning and the ignition 'cuts out' after a second or two. Using the engine-heat button makes a slight difference but the ignition is still cutting out a few times after only turning over for a second or two (and Ive glowplugged 3 times). Once the engine is warm after a wee drive it starts first pop, but at the end of the working day its still taking a bit of encouragement to get going. I keep it in a closed garage at night so its not exactly polar conditions.

So my query is - is this just a result of cold mornings or should I be taking other factors into consideration.

[James W]

The engine heat button won't do anything at all at startup to heat the engine. It's an accelerated warm up system. It advances the timming. You might note is it is a lot more 'knocky' for the first minute or so. It also adds a restriction onto the exhaust to create a small load. This is all assuming it's working properly. The light inside the button comes on right? Also don't drive with the accelerated engine warm up enabled... appart from behaving slightly funny I don't think it does it any good. Most certaily don't go drag racing.... :-)

What often happens around this time of year is the Diesel is changed over from a summer blend to a winter one. It gets a bit guggy, waxy or simply thicker in the cold. You might find on the next fill of diesel it stops doing it. Mine was doing this last week, coughing and failing to start right up, and this week it is fine outside and layers of ice over everything.
This I have noticed happen each year. Try a new fill of diesel. :-)

[Burty]

I would not have even thought of that. Cheers.

Funny what you say re the engine warm up because it wont idle without stalling unless I flick it on for 20 or so seconds (green light comes on) then it settles down immediately and runs fine till I get 100m up the road then I turn it off - the ignition wont even turn over for more than a second unless I turn it on.

[James W]

Hmmm, thats a new one on me... What engine/year/model?

[Burty]

1995 MU manual 3.1 diesal 4JG2.

[Garth]

Re cold starts on a 3.1, these engines need a lot more glow plug to get started when cold than the older 2.8's due to head design.
Pays to glow once for duration of light, then turn ignition off and do the same again. Also the glow plugs do not actually turn off when the light does, if you look at the voltage gauge when you turn the ignition on it drops to around 10v, then the light goes out but voltage stays at 10v, about 5 to 10 sec later the glow plugs turn off and voltage will have come back to around 12v (if you haven't started the engine).
Assume this is to help your engine warm up quicker and run smoother on initial startup.
Might pay to check you get a good voltage drop indicating your glow plugs are definately working for the full time.

[Burty]

Cheers.

Im turning on the ignition untill the glowplug light goes out three times each am - and a couple of times in the afternoon.

It seems reluctant to turn over at all now and Im thinking perhaps starter motor. i.e. this morning glowplugged three times and almost the instant I turned the key to get things cranking there is a very brief noise (like the starter isnt 'catching') followed by a short wirr as everything cut out. Actually getting the engine to turn over now seems to be the issue - however this am it turned over long enough to start ok after only turning the key ever so slightly and holding it for a second or two.

Any ideas as Im a bit stumped?

[mudgrip4]

A thought - might be worthwhile taking vehicle in and getting battery checked - charge, and importantly, load tests. Your symptoms sound a bit like dying battery, and this can also cause starter motor to sound a bit odd when cranking over. Worth a look

Mike

[James W]

I had starting problems just like a bad battery, replaced it, and it got worse... it was the starter. Don't replace as a matter of course, get the battery tested

[geeves]

test the resistance of the glow plugs. Not sure what the reading should be but they will all be the same unless faulty

[Burty]

Could very well be the battery - according to the voltmeter on the dash its holding around 9-10 volts, so when its been driven for a bit its holding 12 volts. I hooked up my 'old' battery to the new one with some jumper leads and she started first pop no worries.

Looks like the battery might be a dud - good thing Ive still got the receipt!

Cheers for the help guys.

[James W]

If the volts are that low I'm not convinced that it is charging, you might have a duff or flakey alternator. Check the belt tension, i had a low battery volts situation recently due to a loose belt... but no belt squel. Also be wary of a battery load test. A good battery will fail if not charged properly. Charge before load testing.

With engine running it should be around 13-14 Volts

[Burty]

It reads about 10 volts in the am - driving its around 14 volts - then once stopped and engine off its 12 volts.

The place I brought it from is going to test it after work - hopefully this might narrow down the problem - fingers crossed.