Diesel Freezing ???

Hazy-thoughts

Guest
Hi all, I have a 1997 hymer motorhome on a merc 2.9 diesel.
Found to my horror last night that it just wouldnt start after starting first time every time ever since I had it. We have been suffering extreme cold temps, it was -6 outside when I woke this morning and I can only think that it will be my diesel freezing. Battery is strong, although weakening due to trying to start, engine seems to be turning fine but just absolutely nothing. I have fuel albeit not a massive amount in there.


What do you guys suggest to try to rectify the problem
 
freezing

hi
it could possibly be water trapped in the filter housing that has frozen as most diesel now days has antifreeze stuff in it to stop it freezing.
days gone by people used to put a bit of petrol in the tank, I'm sure someone will have better idea's
is it possible to put a heater under the engine to keep it warm overnight?
good luck

tranivanman
 
the temps we have in this country wont freeze diesel you may have some water in the system that has frozen but i doubt that that will be causing the problem . with your low fuel you may have air in the system so put some more fuel in and bleed the system see if that works .never realy had much to do with diesel engines never been my cup of tea realy. only had one diesel a pug 405 and i kept trying to run it on petrol .!!!!!!!!
 
Any sort of auto cold-start sequence that might not be working. Glow plugs, air preheater???
 
Glow plugs or relay probably. Do you get the glow plug light coming on?

AndyC
 
Did you wait long enough before attempting to turn the engine over?

Also try the glow plugs twice or three times before trying to crank the engine.
 
All good advice you received. I put a cup full of petrol in each full tank of diesel it helps stop the diesel from waxing / freezing.

Cheers

:)
 
AndyC said:
Glow plugs or relay probably. Do you get the glow plug light coming on?

AndyC
Click to expand...

After reading these posts I went out to my MH, and stared the engine, it started immediately. It is the first time in 2 weeks. I don't think I have a glow lamp or whatever. It is diesel, German model.
 
David & Ann said:
After reading these posts I went out to my MH, and stared the engine, it started immediately. It is the first time in 2 weeks. I don't think I have a glow lamp or whatever. It is diesel, German model.
Click to expand...

When you turn the ignition on a light should show on the left of the speedo it is yellow and has a picture of a coil. This is the glow plug light and you should wait until it goes out before you crank the engine over. If it isn't working your glow plugs aren't working.

As maingate says.
Did you wait long enough before attempting to turn the engine over?

Also try the glow plugs twice or three times before trying to crank the engine.

Another ruse is to preheat the intake air with a flame but make sure you don't draw any material into the air intake from an oily rag. My old Commer had a pot of diesel with a plug that ignited it and it drew this flame into the air intake as it was cranked over as a means of starting. I have used a Calor burner or Gas Fire lighter poker to do this as well.

Diesels will also start on LPG drawn in through the air intake.
 
you can also use ether based easy start but you should be warey ,if you manage to get unburnt easy start or lpg which is a new one to me and sounds a bit iffy in the exhaust and the engine fires up bang goes the exhaust system . also i read someware that if using easy start you must disconnect the heater plugs first
 
mandrake said:
you can also use ether based easy start but you should be warey ,if you manage to get unburnt easy start or lpg which is a new one to me and sounds a bit iffy in the exhaust and the engine fires up bang goes the exhaust system . also i read someware that if using easy start you must disconnect the heater plugs first
Click to expand...

I used LPG to start a non starter in the wilds of NW Scotland after an engine change. It fires up straight away with the compression. I ran it until it drew diesel through the system on an old Ford 6D bus. If it got into the exhaust it just burns, it would only explode if the exhaust was blocked off.
 
Hazy-thoughts said:
Hi all, I have a 1997 hymer motorhome on a merc 2.9 diesel.
Found to my horror last night that it just wouldnt start after starting first time every time ever since I had it. We have been suffering extreme cold temps, it was -6 outside when I woke this morning and I can only think that it will be my diesel freezing. Battery is strong, although weakening due to trying to start, engine seems to be turning fine but just absolutely nothing. I have fuel albeit not a massive amount in there.


What do you guys suggest to try to rectify the problem
Click to expand...

-6C will get the diesel a bit cloudy not frozen by a long shot, it just maybe cold enough to cause a bit of separation in the fuel filter mounted up on the engine, it might even get some wax to form on the paper elements as well. You can give the fuel filter a dose of fresh fuel from the tank by using the manual lift pump on the back of the injection pump. If the pump is rock hard and wont pump at all its a fair sign that the filter is blocked.

You can try a hair drier on the filter and injection pump fuel lines to warm things up enough to get you going, or a hose of hot water over the fuel pipes/pump.

Aerostart (ether) as mentioned is a good way to get things going - BUT - you have to know that fuel is going through the injection pump to keep the engine running.

Try clearing the water separator - located either before the lift pump or on the front of the fuel tank, some 2.9 engines (pre electronic) did not have one at all.

In years gone by in really cold weather the trick was to light a small fire under the engine, surprising how many trucks went up in smoke!!!
 
modern diesels have far more sophisticated starting devices fitted ; eg , in 1998 fiat changed to a triple play control system , you get a pre-heat [ continuous light ] , when that goes out it heats while you start [ no light ] , then a flashing light ,still heating while the engine gets above dead cold [ am told that is +4C , but can't confirm ] ; this also applies to my motorhome , which doesn't have glowplugs but a thermostarter

I suspect yours hasn't got this , mercedes are pretty conservative and tend to be slow in introducing new developments ; if the light flashes after starting it almost certainly has however

try the old trick of double heating .....pre-heat the glowplugs and then switch off ; pre-heat again and try to start ; how long does the pre-heat light stay on anyway ? it should be a lot longer in these temperatures

you DO have winter diesel in I presume .....in the uk the mix tends to change end of october if I remember correctly , and is then good for -15C
 
Last edited:
thinking further about your problem , may I suggest the following
the most common causes of your problem are

worn out glow plugs or
faulty glow plug timer

if the double heating trick doesn't work it can still be either ...just because the light works doesn't guarantee that the glow plugs are heating , the timer may have lit the light but not provided electricity to the plugs

so find the contact to which the plugs are connected ; using a jump lead or similar , connect that contact to the +tive on the battery for 10 seconds ...try to start the engine ; if it starts , you are 99% certain to have a faulty timer , if it doesn't , it likely to be the plugs
as an example , I had to move the motorhome yesterday , at -6C it started instantly without turning over at all ...and it still has summer diesel ; of course , it is a fiat :cool:
 
I was told by an HGV mechanic that it was not a good idea to leave the fuel level low as condensate formed inside the tank and this would then freeze. Don't know if this of any help but it seems to work for me, or have I just been fortunate?
 
Last edited:
As already suggested make sure the glow plug light has gone out before trying to start the van and heat the plugs twice,if the glow plugs are worn in some cases it might start up rough on maybe 3 or even 2 cylinders at first and then build up to all 4 cylinders or 5 if your van is a 5 cylinder,if thats the case get them changed,cheers Chris.
 
Well we have just had the very same problem with our hymer,but this time its a fiat engine.We are currently in Manchester and the temp has not gone above freezing for 4 days.We are the same as the original poster never a problem starting,so this is a first for us.Definately a problem with the cold,and have tried prior to coming on here multiple heating of the glow plugs but with no success.Have left the van with the truma on to determine if putting some heat in the van will work,although a bit of a long shot.
 
You must log in or register to reply here.

Users who viewed this discussion (Total:0)

Back
Top