OK - the list is getting much much smaller now. It is beginning to sound like the GP's.

As said before, and wisely so, diesels really only need compression and diesel and they will go BUT this engine is indirect injection and this changes things slightly; when I had my 2.5NA with less than 40,000 on the clock it would not start without glows 90% of the time, and the only times it did was in the summer after a whole day of sitting in the sun.

These engines have a separate combustion swirl chamber up in the cast iron head, which has some disadvantages, the chamber surface area increases the air cooling on a cold engine, which makes it harder to start because you need to get lots of heat so you really need the GP to be spot on or you are goosed.

With the interior light on, or the head lights or something, turn the glow plugs on, the light should dip noticibly as the GP's draw about 40 amps - if you don't get this make sure the electrics are getting the power there, if you are SURE that a good 12V feed via GOOD connections is making it to the glow plugs then assume several are goosed or they are all working very poorly. Also make sure the connections to the top of each plug is good, might be worth taking the terminals off them all and giving them all a clean up.

Let us know how you get on.
 
can i just start by saying how helpful you have been so cheers for that!!
just went and checked the current coming off the red GP wire(wire straight from battery before it joins the first GP and the rest of the harness for the individual GP terminals.) the voltage was reading 12 so therefore it must be perfect as this is the same as the bat.....? i took the yellow harness wire(the wire that conects the individual GP's together)off and ran a current through it to check for breakages in the wire. this also had a current running through although it was weak (i think this was down to the weak battery in the voltage meter)
by the sounds of it, it is all in good working order in terms of electrical components. i will use a wire brush to clean up the terminals and then see if its any better. is it likely that by having a small amount of crud on the terminals it would effect it this much?

thanks
ed
 
you've still not done the one thing that could give you a massive clue as to what the issue is have you

i give up
 
you've still not done the one thing that could give you a massive clue as to what the issue is have you

i give up

no i haven't your right. but instead of using this testing method on old GP's i thought i would wait for the new ones to arrive. by doing this i can 99.9% confirm that it if they were not red hot within 30 sec or whatever then the problem is further down the harness!!!!! . so, therefore, whilst waiting for the new GP's to arrive, i tested the GP wiring harness first to see if there was a strong current through it.
 
why not just pull them and check them in situ - might have saved a few quid and some fannying aboot

ah well
 
no i haven't your right. but instead of using this testing method on old GP's i thought i would wait for the new ones to arrive. by doing this i can 99.9% confirm that it if they were not red hot within 30 sec or whatever then the problem is further down the harness!!!!! . so, therefore, whilst waiting for the new GP's to arrive, i tested the GP wiring harness first to see if there was a strong current through it.


NEW doesnt always mean good ;)
 
i was thinking that. I swapped my plugs for new ones, and it bought me absolutely no benefit whatsoever!
 
yer this is also true.
the reason why i got new ones was because in taking one of the GP's out i managed to sheer the terminal attaching thread so i kinda needed to get at least one new one. and i thought as i was replacing one i may as well buy a new set!
 
can i just start by saying how helpful you have been so cheers for that!!
just went and checked the current coming off the red GP wire(wire straight from battery before it joins the first GP and the rest of the harness for the individual GP terminals.) the voltage was reading 12 so therefore it must be perfect as this is the same as the bat.....? i took the yellow harness wire(the wire that conects the individual GP's together)off and ran a current through it to check for breakages in the wire. this also had a current running through although it was weak (i think this was down to the weak battery in the voltage meter)
by the sounds of it, it is all in good working order in terms of electrical components. i will use a wire brush to clean up the terminals and then see if its any better. is it likely that by having a small amount of crud on the terminals it would effect it this much?

thanks
ed
Common mistake is thinking that volts are the same as amps.
You need mucho amps to heat glow plugs, the voltage is not so critical within a few volts.
12v shown on your meter does not necessarily indicate a good supply to the GPs. Your meter draws next to no current when measuring voltage so any high resistance in the supply line will not show. As already said you need to take out the GPs and see if they glow with them grounded and connected to their normal wiring. Try to get all four glowing at the same time as there may be enough current to heat one plug but not all four if there is a high resistance connection somewhere.

Another quick and dirty way to make sure the GPs are getting a good supply is to temprarily run a heavy cable direct from your battery +ve to the GP harness. Take off the normal feed and insulate it so you dont get any strange backfeed problems. Be careful because if you ground the temporary cable it will likely melt or catch fire. Make sure you use a cable able to carry at least 50amps. If this solves the problem then you have wiring issues in the GP feed.
 
I would re-stress the not-touching-the-accelerator-till-it's-fired point.

If you touch the accelerator before the engine has fired, the cold start mechanism will reset and not work properly which will make it really hard to start.
 
Just went and checked the current coming off the red GP wire(wire straight from battery before it joins the first GP and the rest of the harness for the individual GP terminals.) the voltage was reading 12 so therefore it must be perfect as this is the same as the bat.....? i took the yellow harness wire(the wire that connects the individual GP's together)off and ran a current through it to check for breakages in the wire. this also had a current running through although it was weak (i think this was down to the weak battery in the voltage meter)
by the sounds of it, it is all in good working order in terms of electrical components. i will use a wire brush to clean up the terminals and then see if its any better. is it likely that by having a small amount of crud on the terminals it would effect it this much?

Hang on a minute, I think there may be something not right here, you must first know that volts and current are entirely different things, you can have 12V at 1mA of current which isn't going to do much, but your meter will read 12V loud and clear.

What you were measuring was the VOLTAGE, you say that along the harness it was weak, you mean the voltage was dropping off? Or were you doing a continuity test on the meter? If this is the case then the chances are there is a filthy corroded connection or join somewhere.

Clean it all up, and without even looking at a meter do the glow plug and light trick I told you about in my last post, that is a good indicator of current draw.
 
right, i just attached one end of a jump lead to the + of battery and the other to the harness with the glow plugs in, all except the last one as it is broken. i then attached the ear lead to the end of the harness and attached it onto chassis. there were sparks every where, and i value my life so is this worng and if so how should i do it?
cheers,
ed
 
right, i just attached one end of a jump lead to the + of battery and the other to the harness with the glow plugs in, all except the last one as it is broken. i then attached the ear lead to the end of the harness and attached it onto chassis. there were sparks every where, and i value my life so is this worng and if so how should i do it?
cheers,
ed

You attached it to the power source +ve first! :doh:

I honestly don't pretend to know a lot about electrics, but it strikes me that clipping on to the positive terminal of the battery should be the very last step! :D
 
right, i just attached one end of a jump lead to the + of battery and the other to the harness with the glow plugs in, all except the last one as it is broken. i then attached the earth lead to the end of the harness and attached it onto chassis. there were sparks every where, and i value my life so is this worng and if so how should i do it?
cheers,
ed

the plugs are earthed through the engine, you in effect touched the jump leads together (through the harness)
 
right, i just attached one end of a jump lead to the + of battery and the other to the harness with the glow plugs in, all except the last one as it is broken. i then attached the ear lead to the end of the harness and attached it onto chassis. there were sparks every where, and i value my life so is this worng and if so how should i do it?
cheers,
ed

If I understand the workings of glow plugs at all, it's simillar to testing spark plugs.:D

Probably safer to do them one at a time. Connect one end of the negative lead to the screw thread of the plug (what normally touches the engine block) and the other end to either the engine block or chassis. Then carefully with the positive lead, attached to the battery positive, connect it to the top of the plug (where the wire normaly goes). And the plug should now be working, just be careful not to let the positive lead touch any thing other than the connection end of the plug or you'll fry the battery and/or all your electrics.

:eek:I'd recomend wearing leather gloves 'cause the plugs will get very hot very quickly:eek:
 
right, i just attached one end of a jump lead to the + of battery and the other to the harness with the glow plugs in, all except the last one as it is broken. i then attached the ear lead to the end of the harness and attached it onto chassis. there were sparks every where, and i value my life so is this worng and if so how should i do it?
cheers,
ed

as Gratch said - yu just shorted yo battery out. :(
 
all good now finally! cleaned all contacts, re-wired loom, new GP's and bled fuel lines! all good starts first time with one crank! thanks for all the helps guys.!
 

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