S3 200tdi - thank you

Hello All.

I originally posted this in the introductions section, but I guess this one is more appropriate.

I'd like to say thank you to everyone who has posted info about converting a Series 3 to 200tdi - I've now finished my conversion and I couldn't have done it without you!

Following much planning and eBaying I've successfully managed to fit a Discovery 200tdi into my 1984 Series 3. The car has been in my family since 1988 and was my first car so has a lot of sentimental attachment. The 2.25 diesel was getting tired so I either needed to sell it and trade up to a 90, take the 2.25 out and overhaul it or fit a 200tdi. I am so glad I went the with the 200tdi option! Its made a huge difference and puts a smile on my face every time I drive it.

I am quite chuffed with how it turned out as I managed to do the conversion without really modifying anything from the original. The only non-reversible changes are two 3" square cutouts in the inner wing and radiator panel which aren't visible unless you look for them. The rest is as-built or bolted on.

I used the series radiator with a 10 core oil cooler mounted behind. The intercooler is mounted in front of the radiator and is from a Fiat Multipla with an electric fan in between (it has the inlet and outlet on one end and is 96% the same core volume). I clocked the turbo as per normal, but had to relieve the inner wing as mentioned to get the waste gate actuator to fit. I even managed to keep the battery under the bonnet. The oil cooler pipes are the only made-to-measure parts. The rest of the hoses and bits came from eBay. Most of the engine conversion parts and exhaust came from Steve Parkers - who were very helpful and gave great advice.

Luckily mine already had a cable throttle so a slightly modified Discovery cable is all I needed. The fuel filter uses the same bulkhead fixings and even the washer bottle fits on the holes left by the vacuum tank. I apologize in advance for the bad-boy air filter - I wanted to use the Discovery one but just couldn't find the space. The heater control valve was a nice find, I think its from a black cab.

The wiring is very simple, I didn't bother with the glowplug relay and the only extra wire I had to run is a switched live for the stop solenoid. The stop solenoid also gets a feed from the start signal when cranking - I used two diodes to stop any back feeding.

If I did it again I would use a slightly smaller oil cooler as the one fitted is very close to the water pump pulley.

Unfortunately I must have damaged the rear crank seal when fitting the modified flywheel housing, so it all needs to come out again. But at least I know all the fixings are new!

I've added some photos for anyone who's interested. I'm afraid they were taken at night so aren't the best quality.

If anyone is interested in more info just let me know.

Cheers, Ric

Well done it looks a very good installation.
Heater supply is not normally valved on discovery but plenty have done it without issue.

Thanks.

Most of the how-to guides I read just leave it out, as you suggest. If I 'm honest it hasn't moved from hot since I fitted it and anytime I want cold air in the cab I use the vents. It just seemed like a neat solution

Very nice job....be carful...I was advised not to fit a heater tap...in case it compromised the flow through the head....I didnt want to risk it,

Have you had a chance to work out your MPG yet,

Mine is fitted as a DI...I get 35mpg on my 10 mile run to work...I hope for better on a longer run as they dont warm up as fast as the old 2.25d...and it goes so much better when warm.

Nick.

+1 on the nice job

Hi Nick.

Thanks for the advise, I hadn't heard that before. In which case I will leave it open - I only fitted it for the sake of completeness.

I haven't done any comparisons with the 2.25 as I never measured it. My gut feeling is that it is better, but I have no data to back that up. Sorry.

I think bigger tyres might make a difference as even with the overdrive it seems a bit under-geared. It's on 205s at the minute and according to the ashcroft site going to 235/85s will reduce the engine speed by 250rpm at 60mph. I'm sure that would improve economy as well.

Ric

honolulujoe said:

+1 on the nice job

Click to expand...

Thank you It was great fun doing it, just need to get the outside sorted now.

i put a bad boy airfilter on mine, without the piping i used a short 90% elbow onto the turbo inlet and airfilter on that and works fine

That was my original plan, but the pipe from the rocker oil vent just seemed to prefer being on that side. I think that hose running across the engine looks a bit odd so I might try your idea.

Looks a smart job you've done there. Does the disco engine drop onto the same engine mounts? I thought one needed modding?

Thank you.

Yes, the 200tdi Discovery version drops straight in. You use the brackets of the 2.25 and I bought the rubber mounts from Glencoyne, not sure what they are originally designed for but they are very good. From what I have read the Defender 200tdi and the 300tdi require steelwork in order to fit.

Ric

ricyoung said:

Thank you.

Yes, the 200tdi Discovery version drops straight in. You use the brackets of the 2.25 and I bought the rubber mounts from Glencoyne, not sure what they are originally designed for but they are very good. From what I have read the Defender 200tdi and the 300tdi require steelwork in order to fit.

Ric

Click to expand...

due to the different timing case on the def' 200tdi the injector pump clashes with the offside chassis mount so requires replacing/relocating

the 300tdi has the oil filter head mounted in a different place to the 2.25 and 200tdi so again requires the offside chassis mount relocating/replacing

i'll be doing a 300tdi disco/Series conversion in the near future myself and fitting both of the 300tdi engine mounts into the Series chassis, i've just got to get my finger out and start chopping up the disco (i also have to convert the engine from auto to manual gearbox)

Nice job, good to see.

Thanks for the info

Have you fitted RR diffs to increase the gearing? My series 2a has a 200tdi with an overdrive and bigger wheels, but the gearing is still a bit low. I'm getting some RR 3.54 diffs for it. I get over 35 mpg, which is a considerable improvement on the 18 mpg with the 2.25 petrol..
Casp'

Hi Casper.

No, the transmission is all standard.

I am a bit hesitant for two reasons. 1) I'm not in my comfort zone with something like changing diffs and 2) For nostalgic reasons I'd like to stick to the original car as much as possible. I know changing the engine is quite the opposite, but I am confident that I could return it to as-built an no-one could tell it had been modified. I know this is an incredibly irrational reason not to change - but there it is

I'd like to hear how you get on though - did you consider upgrading the transfer box as well? Or does it have an effect on the overdrive?

Cheers, Ric

Hi Casper.

I just answered my own question, according to the Ashcroft site:

"Please note this kit cannot be used as well as an Overdrive but you can still use the rear PTO"

If in doubt - google...

Ric

i personally would change some of the transmission (diffs are cheapest) to raise the overall gear ratios (on a S3 no-one can tell unless they look for the filler plug in the diff), the reason why i would change the diffs is to gain the required fuel economy (not all 200tdi's give the same mpg so don't be fooled) and reduce the wear rate on the engine by reducing the engine speed (rpm) for a given road speed

some folks are against the diff swap due to it raising the low box ratios by the same percentage but i haven't to date (5 years of use) found it to be a problem when laning or in pay and play pits

where the problem may arise is in increased stress on the gearbox but you would be putting the same stress on it if you fitted the high ratio transfer box

the problem (to me) with fitting the high ratio transfer box is you cannot fit an overdrive, so then you can't split ratios should you want or need to, i like my overdrives

the final change in ratios is down to the size tyres you fit, i run 7.50x16 tyres on both of my Series (both fitted with 200tdi engines) which gives an overall increase in gearing of near as dammit 30% over a standard 88" fitted with 6.00x16 tyres

WITHOUT upping the ratios first gear is completely redundant and you could possibly pull away in third when empty on the flat (not a good idea), i have been known to forget to switch my overdrive out and pull away from a standing start (not ideal really), PLUS you'll hit the rev limiter in top gear really easily which again is not ideal

in the past 5 years i've had 2x (very cheap secondhand) S3 gearboxes get very tired and growly and 1x S2a gearbox lose a layshaft bearing (has made reverse growly and chipped 1st)

both of mine are daily drivers, used and abused and have to earn thier keep, my 88" has just hauled another 88" back 80-90miles from North Wales and has dragged discos up to 50-60miles when needed, the only thing that has stranded me to date with both of them has been busted timing belts and one castle nut undoing itself in the back of the gearbox

there you have it, in my opinion you have a choice between excessive wear (and fuel consumption) of the engine or the possibility of wearing out your gearbox faster

p.s.
looks to be a nice tidy installation

p.p.s.
the ideal (in my opinion) diff ratio to go for would be 3.9:1 but they're rarer than rocking horse poo

ricyoung said:

Hi Casper.

No, the transmission is all standard.

I am a bit hesitant for two reasons. 1) I'm not in my comfort zone with something like changing diffs and 2) For nostalgic reasons I'd like to stick to the original car as much as possible. I know changing the engine is quite the opposite, but I am confident that I could return it to as-built an no-one could tell it had been modified. I know this is an incredibly irrational reason not to change - but there it is

I'd like to hear how you get on though - did you consider upgrading the transfer box as well? Or does it have an effect on the overdrive?

Cheers, Ric

Click to expand...

If you do want to raise the gearing, have a look at the Ashcroft high ratio transfer box. In some ways it is a better idea than changing the diffs. It doesn't raise the ratios in low range, so you still have a nice low box for off road, and it is much stronger than Fairey overdrive.
I have had them in series before, and I was really pleased.

Very workmanlike job of the installation by the look of it

NiteMare said:

i personally would change some of the transmission (diffs are cheapest) to raise the overall gear ratios (on a S3 no-one can tell unless they look for the filler plug in the diff),

Click to expand...

I have managed to source some recond Range Rover classic diffs, which have the increased gearing and have the required filler plugs, so almost impossible to tell. I'll keep the original diffs as it's an easy job to reinstate them, far easier than putting the original engine back.. I'm told the rear diff is an easy swap, the front, not so easy...
Casp'