200TDI and 300TDi refinement/noise?

[twodoorgaz]

I promise I'm not going to try and start a 200 vs 300 TDi engine thread. That was done to death 10 years ago (just had a good chuckle reading through some older posts on the subject). But I would welcome some additional information on the 300TDI 'being quieter/more refined' line that is often repeated.

 

For background, I've had a lot of Land Rovers - most recently a Puma 90 and prior to that a pair of 300TDi discoveries in parallel to a lot of Series IIAs/IIIs - so I fully understand that 'refinement' in LR circles is a relative term. On Friday I'm going to look at a RRC that I plan to buy - its an import and is almost rust free (genuinely) and is a factory 200TDi - I'd be buying the vehicle for its condition, the engine is a secondary concern as I could change it to anything during the restoration process if I chose. I don't think I will as the 200TDi has always been on my ownership bucket list and the RRC is a base spec, so no luxuries/electronics to 'spoil' with the absence of V8 noise - think of it as a more comfortable Defender.

 

It is being bought to take back to a bare shell for a long-term restoration, so I have ample opportunity to subtly add soundproofing and dynamat etc.

 

So, my query is: to what extent did the the 'refinement' comments of the day relate to the nature of the engine itself and how much was relating to the additional soundproofing added to the facelifted vehicles? Its probably best to think of Discoveries and Range Rovers here rather than Defenders.

 

In my mind the 200 was considered noisier due to:

(from older LR4x4 posts) 300TDi dual stage injection being quieter in retrospect than 200TDi single stage

(from my head) The 300TDi had an acoustic hood which may have had a minor effect (which I also believe is a direct fit onto a RRC 200TDi, if anyone could confirm this I'd be grateful)

(a guess, but...) Was the 300-era/1994-1999 discovery produced with better soundproofing on the under bonnet/bulkhead/transmission tunnel?

 

Is there more to it than that?

 

If I could bridge the gap a smidge between 200TDi's agricultural nature and the 300TDi's 'smoothness and refinement' I'd be chuffed.

 

PS: not looking to swap to a V8 at this stage.

 

Thank you.

Edited January 12, 2023 by twodoorgaz

[Gazzar]

Better engine mounts and a buck tonne of noise management. That, and the already superior body to chassis mountings of the RRC, should make it a civilised place, compared to the defender. I've had a TDI 200 disco; a very nice place to be. Look up old reviews.

[pat_pending]

My mate's 300tdi auto 130 is definitely smoother than my 200tdi auto 110.

But how much of that is down to the different engine mounts and sound proofing I don't know.

For what it's worth, we MOT a 110 with the sweetest 200tdi ever.

The owner says when he bought it he was told the engine had been rebuilt and knows no more than that.

This thing just purrs.

So as to actual engine "smoothness", it's certainly possible to get a civilised 200.

[western]

Quote

from older LR4x4 posts) 300TDi dual stage injection being quieter in retrospect than 200TDi single stage

 

200tdi injectors are 2 stage as well, initial pressure of 200 atmospheres 2nd stage of 280 atmospheres according to my workshop manual. 

Quote

from my head) The 300TDi had an acoustic hood which may have had a minor effect (which I also believe is a direct fit onto a RRC 200TDi, if anyone could confirm this I'd be grateful)

Yes the RRC 200 did have a rocker cover sound proffing but it isn't as thick as the later 300tdi item, I have a trimmed 300tdi item on my rocker cover. 

[miketomcat]

I have two discovery 200tdi engine's one in our 110 and one in my ibex. Both are solid mount body to chassis, my ibex has fractionally more sound deadening. The ibex has discovery engine mounts and 300/td5 gearbox mounts, the 110 has original 200 defender mounts. The ibex is definitely quieter and smoother than the 110 but not much. I'd say there's not a lot in it between my ibex and tsd's with a tgv in.

Mike

[rusty_wingnut]

I think the one issue with this is that you don't have an under tray - and as much as you sound proof bulkhead bonnet etc you cannot prevent the noise under the car.

[elbekko]

I had a factory 300TDi RRC ('95 Softdash) with an R380.

Refined it never was. Sounded like a bus, drove a bit like one too. Motorway on-ramps were interesting, and the one near home at the time had a sharp 90 degree bend at the bottom, and then a hill up to the motorway. This is where I learned to corner an RRC quickly Otherwise there was no hope of getting to 90 kph by the time I got on the motorway, especially without hurting a usually cold engine.

The main NVH was from the gearstick. Under load it was alright, but sitting at the traffic lights you could shake a cocktail with it. No different from a Defender, I guess.
There was thick sound deadening matting that did help. I removed that after it got soaked at some point, and things definitely got louder then. The worst was when I swapped out the BW for an LT230, the gear howl from that was atrocious without sound deadening.
I don't think the little cover on top of the engine did much, I drove with and without it and never noticed a difference. Same with the mat inside the bonnet, that may stop some engine noise for people outside the car, but inside the car it doesn't do much.

One of the main things you can do to make a TDi sound "smoother" is to make sure the valves are always correctly adjusted, excessive valve lash can cause a really annoying ticking that is easily heard in the cab.

On one hand it'd be a bit sad to modify a (rather rare by now) 200TDi RRC, but on the other hand if you're doing a full rebuild anyway, you might as well fit a nice V8 or a nice 6-pot diesel like an M57. Those would be much better suited to the type of vehicle it's supposed to be. If you just want a Defender with better seats, it'll suit you perfectly.

[Nonimouse]

The 200Tdi RRC is a lovely vehicle and rare. I've had one and I now drive a 200 Disco

You can make a 300tdi cover fit a 200 but it involves a sharp knife and to be fair I don't find much difference

The 200 is crisper and easier to improve the tune on on - ignore all the boost pin silliness. It's also better on fuel. A200 Tdi RRC was used for the drive from John O Groats to Lands End, on one tank of fuel.

The engine mounts are the very advanced Disco type.

Escape has hit the nail on the head. Service the engine, properly. Get that valve train right. I also run a 200ml of two stroke oil per tank, this quietens the engine down.

I'm told the speedy shift that Shabs Percy makes, will quieten the gearstick chatter, but you will still get the clutch chatter - that's normal.

Running 300tdi nozzles on 200 tdi injectors seems to quieten the engine slightly

finally, every 200 is different. Some pull like a train in standard form, some are louder than others, some are really responsive to tuning

[monkie]

I don't think either tdi is known for smoothness and refinement, its just not their thing. Economy and robustness is what they are designed for. I'd say ensuring they are well serviced, correct timing and a set of good injectors along with quality engine mounts are things to focus on. 

[Snagger]

My 300 was a fair bit quieter under the bonnet than my 200, so some of it down to the injection system.  But most of the benefit on the RR is the other stuff you highlighted - mounts, matting and mass dampers.  The gear stick should have a damping sleeve for that purpose.  My 95 300Tdi/R380 RRC experience seems quite contrary to elbekko’s.  It’s not like a V8, but is no slouch in standard guise and is not loud inside.  The only annoying noises I suffered were the crunch on quick changes from 1st to 2nd when warm, a tapping from the engine that I’m confident was the vacuum pump rather than tappets, and a bit of brake pad rattle when crawling around tight spaces.

 

Out of curiosity, are you rebuilding the body yourself or having it done?  I am visiting Twenty-Ten and  Revival Vehicle Restorations (referred by Bishop Classics) in a week’s time to decide on which I will be using for my body restoration.  I need to think about many of the questions that I need to ask.

[Daan]

A lot is in the in the mounts and injection. For a 200, I would replace the engine mounts for Glencoyne ones. They are meant for series conversions, but should fit any standard 200 TDI application. the 300 has different mounts, but they are much better, and I think part of the reason the 300 is quieter.

Then injection, I think investing in a timing tool that clocks the pump allows you to set it up the way you want. I reckon the timing and fuel delivery is what makes the difference between different engines, as mentioned they vary quite a bit.

And try to vary the timing a bit even if outside factory specs, just to see what it does.

I think a TDI is by far the best suited engine land rover made for working vehicles. simple to fix, plenty of low down torque good parts availability (300 mainly) and cheap to run by comparison.

[western]

You can see the RRC 200tdi cover on my engine in this thread from 2011 

More photo's of the cover in ERR3276 200Tdi rocker anti noise cover

[fmmv]

I have just had a fuel pump rebuilt, and that had quite an effect on noise, as well as on power. Timing is also a factor, advancing to get best power will increase noise. You  pays your money ...

Edited January 13, 2023 by fmmv

[Daan]

The 300 version is far bigger and more effective:

https://www.ebay.co.uk/itm/304769911371?hash=item46f5b3ca4b:g:REkAAOSwGMNjwdD6

I am pretty sure my dad fitted the same to his 200 disco.

It might clash with the turbo on a defender 200 though as this is mounted higher.

[western]

I cut a used one so it left me with the rocker cover section, the intake manifold would interfere with Defender 200tdi turbo. 

[Snagger]

I did the same, cutting the manifold cover section away as the Defender version of the 200 has the exhaust manifold above the inlet manifold, so the cover would ignite.  Every little helps…

I have the early Glencoyne supplied, Bearmach made mounts on the engine and standard SIII diesel (square) mounts for the transmission on the 109.  I got a pair of the newer, specially made Glencoyne mounts more recently so they will go on the engine and the older type will move to the transmission.  That should help a lot - 200Tdis make a racket in Series vehicles. 

[markyboy]

On 1/14/2023 at 4:43 AM, Snagger said:

I have the early Glencoyne supplied, Bearmach made mounts on the engine and standard SIII diesel (square) mounts for the transmission on the 109.  I got a pair of the newer, specially made Glencoyne mounts more recently so they will go on the engine and the older type will move to the transmission.  That should help a lot - 200Tdis make a racket in Series vehicles. 

I have the 'new' Glencoyne mounts in my Discovery 200Tdi swapped Series 3. The comparison between that and the Discovery 200Tdi swapped 90 of my brother in law was night and day, mine was much smoother/less vibration. Different vehicles, of course, so not clear cut. However, based on my car,  we fitted a pair of the Glencoyne mounts to his 90, it made a huge difference to the amount of vibration and noise.

Mark.

[Snagger]

Tdis seem to be very rough in Series compared to Defenders, even the same engine on the same rubbers.  I think it must be a harmonics issue with the chassis dimensions or perhaps the suspension, leaf springs not absorbing as much vibration as coils.  Speculation on my part, but there is a pronounced trend.  So, if you got your Series smoother than a Defender, that is superb.

I was very impressed with replacing just the engine mounts.  Should be a big improvement with all four done, all the better for using the newer type on the engine.

[markyboy]

42 minutes ago, Snagger said:

 So, if you got your Series smoother than a Defender, that is superb.

I think it was only smoother due to the age of his original engine mounts of 1986 vintage! 🤪