110 2.5td to 200tdi glow plug problem

hi,

im new here so dont shoot me please. im close to to finishing converting my 110 2.5td to a 200dti with out much of a problem ( i had lots of help) but iv got a small problem with the preheat. should i just use the pre heat on the key like the old 2.5td or use the preheat timer system of the 200tdi (cant work out the wiring) any help would be very help full.

if it was me i would leave it on the key my 200tdi has never needed the glow plugs and always started on the botton even in all the snow

you'll end up replacing the ignition switch if you run 200 plugs via the existing ex TD supply - better bet is to use the thick brown wire to feed the 200 relay/timer so that the ignition switch only has the low current relay coil current through it

so are you saying the 200 glow plugs draw more current than 2.5na or TD glow plugs?

I have my 300tdi Glows on the standard leads from the 2.5na have done for best part of 2years never had a problem, if i was you i would leav it.

jai_landrover said:

so are you saying the 200 glow plugs draw more current than 2.5na or TD glow plugs?

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no

Glenn321 said:

I have my 300tdi Glows on the standard leads from the 2.5na have done for best part of 2years never had a problem, if i was you i would leav it.

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the ignition contacts will fail sooner or later, they all do due to the high current - changing it is a pain

however, it's VERY easy to fit the 200 relay/timer so the ignition switch then only has to provide current for the coil

What about just not connecting them up at all - just a thought to aid discussion - would go with sean's plan myself

For simpleness no hassel out in the wilderness I would just link them up to your old ones. You turn them on and control them no relay to get wet and go wrong. Ok so I can see where sean is comming from sorta, but I don't see an issue really In reality they will probably hardly ever get used if the Tdi is good and worthy of the effort of transplanting it. Even if they are used propperly the wiring and switch if in working order should be just fine mabe a dusty ****ty half burnt out already contact will burn out have a higher resistance but only if its shagged already. Mine is on the old key switch and mine is the original 1986 key switch it has always worked well for me each and every time. They will always be used if you link the relay up each and every time you start. Swings and round abouts depends what you want.

no right or wrong here just personal choice. Me I'd rarther not rely on a relay more things to go wrong on a cold snowy morning however sean would argue that he wouldnt rely on a key switch. Swings and roundabouts!

The amount of current going through the glo-plugs, uee a relay - so you mite as well use a timer relay.

jai_landrover said:

no right or wrong here just personal choice. Me I'd rarther not rely on a relay more things to go wrong on a cold snowy morning however sean would argue that he wouldnt rely on a key switch. Swings and roundabouts!

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swings and roundabouts my arse

option 1 - set of contacts integral to the ignition switch taking high current direct to the plugs

option 2 - set of contacts integral to the ignition switch taking minimal current providing power to the relay coil

you gotta be a bit dim/ignorant to think option 1 is preferable ?

jamescronin said:

What about just not connecting them up at all - just a thought to aid discussion - would go with sean's plan myself

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my 200 doesnt need plugs either

So did LR not design or use a switch rated to take the current in the first place? You have already stated that the current draw is no more than the Td's and na's glow plugs.
Therefore TD's or na's shouldn't use their glow plugs because the switch is not up to the job. Erm well mines working fine thank you it has done all its life and its 24 years old.

Not up to the job?
Not doing exactly what it was designed to do?

I said I can see your point sean why you want to go fitting a relay but the switch if in working condition is more than capable of passing the required current needed to turn your plugs on. Mabe if there is other faults/dirt/grime/corrosion on the switch/contacts I can understand you having some problems and possibly a resistance giving poor plugs. But I still state if the switch is in good condition there is no NEED to go changing the wiring to bypass somthing that was designed to deliver the same required power to the glow plugs time after time (24 years) and hopefully some more years to come.

stuff the plugs, yer wunt need em - just put em on the key then you can use em if you find you do need em, if yer running a particualrly high concentration of veg oil or it's REALLY cold!

Oddie said:

stuff the plugs, yer wunt need em - just put em on the key then you can use em if you find you do need em, if yer running a particularly high concentration of veg oil or it's REALLY cold!

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Aye, seems the least-hassle answer, even up here in the frozen north - but I will retain the relay/wiring just in case........can always fit later if required

remembering the OP has the wiring and engine out in the fresh air due to the conversion

it'll take an hour and a tenners worth of parts to retro-fit the 200 relay/timer - it's then the relay that does the work - if it fails it's a 2 minute job and the price of a pint to replace

take the easy route and wire the 200 plugs direct from the existing ignition key feed - great job done in 5 minutes - so what happens when that 20+ year old switch at the back of your ignition switch fails (and it will fail far sooner than the relay) ?

so the options again

option 1 - carry on using an eldery switch to carry a high current and run the risk of it failing, resulting in the need for a good few hours work along with the expense of a new/replacement ignition switch

option 2 - while it's easy to do (seeing as the engine is out) take an extra hour to wire in the relay/timer - thus giving that overworked elderly switch a peaceful and easy retirement and allow a easy cheap to replace relay to do the hard work ?

i'm sure you'd not run a set of lights direct through a switch would you ?

It is however different if the conversion was done on a petrol vehicle and the guy used a petrol ignition switch that is most definatly NOT rated high enough to take such high current.

Have you seen the size of the connectors on the back of the Ignition switch on a diesel? They are huge.

Changing the ignition switch is not that hard 2 hours are you being serious???? Plus after 24 years or longer are you really going to worry about half an hours work? Its no real hardship and I would suggest if your switch is that knackared, changing it would be a wise move. Afterall its worked on countless LR's I'm not saying don't fit the relay I'm just saying there is an argument not to fit it if the wiring is already there and is working a ok and rated for the job.

I admit that Relays are very very useful and save money by using cheaper wiring and switchgear to perform the same operation. Problems come with people don't use rated wire nor switchgear and or wire it, in such a way as to be dangerous. Wires carring high current wedged under seat boxes and the like we all see on other vehicles. It is far more desirable and nice (lets all be honest) to use a low current circuit and a relay to switch a high current circuit because of cost of switchgear/wiring and ease of hiding smaller diameter wires. In fact it is good practice to use a fused Relay etc with the added advantage of picking up a low current wire to use as a live for the low current side of the circuit opposed to running a high current cable to wherever. Again all good practice and cost saving.

Although there is no problem if you used rated switchgear, wiring and fuse if you fancy spending lots of dosh on the above components and make wiring all that expensive cable a nightmare. As LR have already forseen the need to switch a high current circuit namley the glow plugs they have put a nice rated switch on the end of the ignition just for that exact purpose with a wiring harness ample to cope with the current load its expected to have applied to it.

Again either way its up to the OP.