300tdi Exhaust gas temperature & fuel pump tuning

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James_mac

James_mac

Active Member
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Leeds & Yeovil
What temperatures are you lot getting from your EGT gauges and how high can it safely go?

I rebuilt my 90 last summer and kept the fuel pump at its original settings so I think it's time for a tune up.
Iv got an alisport intercooler and a EGT gauge fitted on the EGR blanking plate, it's only a cheep one so I'm not sure how accurate it is, on a long incline with my foot to the floor I get around 500'c at a push, during normal driving it's normally around 2/300ish. How does that compare to everybody else?

I'm going to adjust then smoke screw, diaphragm and star wheel soon and monitor my EGT so I don't cause any damage, anybody know what temp not to go past and the average temp for a tuned pump.
 
Saint.V8 said:
I think the critical temp is quoted as 700-720 degC from memory....do your tweaks, and try not to exceed 660-680degC I'd say
Click to expand...

I agree with both figures quoted above:). - I've been told the same figures - perhaps a bit more accurately - in as much as the head will take 719 C - but at 720 it's all over :eek:..... I took this "detail" with about the same pinch of salt you should o_O...

because...

1) I don't want my engine to die (!), and

2) even though I have checked the gauge with an IR thermometer, there are a few variables which I can't quantify, like the delay in the response of the gauge and the accuracy of my placement of the IRT.

I rarely look at my EGT now in normal driving, but 200 - 300 C is about right IME. If I am towing, then I limit myself to 650C - because the time to climb from 650 to apocalypse is very short..... :eek:

If you tweak the pump, get a boost gauge too, and you can manage the fuel based on boost levels and EGT - I could not drive with my foot to the floor with my set up - I would smoke the place out - and empty the fuel tank in short order.

Also, at these higher temps, be aware that your alternator is in very close proximity to the exhaust, and unless the heat shield is in perfect order, you can add an alternator to your shopping basket too :rolleyes:

Can you guess how I know this :rolleyes::mad::rolleyes::mad::mad::mad::(

I intend moving mine out of the way at some point... but for now have spaced the heat shield further back from the alternator to allow more airflow.

A very obvious point is that on a hot day, the temps will rise more quickly - but your IC will also be more efficient - this might catch you out - you can actually buy alarms for the temperature too.... might be worth it, might not, YMMV :)

IMHO LR designed this setup quite well, and in standard tune, they are more or less indestructible - not so when they are tuned. Mine is tuned to 145 HP - it's possible to tune the 300Tdi to 200HP - BUT I suspect its life at this level will be short.....:(
 
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After my engine (300Tdi) carped several weeks ago I've spoken to a few companies for bits. Turbo reconditioning place asked, when I explained the piston No4 had melted a bit, have you removed the EGR valve? Turner Engineering, when I told them the same and also rings in piston No1 had snapped asked if I'd modified the engine at all, eg tweeked the pump? They thought it getting hot was likely the problem with the rings. Not sure though as it doesn't get driven hard. Can't see why No1 running hot would affect rings in No4. Just wondering out loud :rolleyes:
 
Al2O3 said:
After my engine (300Tdi) carped several weeks ago I've spoken to a few companies for bits. Turbo reconditioning place asked, when I explained the piston No4 had melted a bit, have you removed the EGR valve? Turner Engineering, when I told them the same and also rings in piston No1 had snapped asked if I'd modified the engine at all, eg tweeked the pump? They thought it getting hot was likely the problem with the rings. Not sure though as it doesn't get driven hard. Can't see why No1 running hot would affect rings in No4. Just wondering out loud :rolleyes:
Click to expand...


Its probably as an old design engine people tweak them so they drive more like a modern car then rag the arse off it, you dont think you are ragging it but compared to how it was as std you are.
I guess egr removal may cause increased cylinder temperatures?
Add in the fact they are all now well worn even the low mileage ones.
The back cylinder always runs the hottest in this case number 4.

I rag my 200 all the time simply because they dont have enough power and I swear the power band is narrower than some old 2 stroke moped:D
 
^^^ another good reason for having decent gauges in place, so you KNOW what is going on under there;), then the ATF, and then the coolant. I'd suggest that its prudent to drive a tuned engine with some consideration if you want it to last..... and I do :)
 
Disco1BFG said:
^^^ another good reason for having decent gauges in place, so you KNOW what is going on under there;), then the ATF, and then the coolant. I'd suggest that its prudent to drive a tuned engine with some consideration if you want it to last..... and I do :)
Click to expand...
Except when you pull up at the lights alongside some old boy in his clapped XR2 ;):p
 
Al2O3 said:
Except when you pull up at the lights alongside some old boy in his clapped XR2 ;):p
Click to expand...

I've done that :) - several times actually - surprised the living daylights out them too - so funny :D

( and then I cool it down sensibly - I.E. not just park up and switch it off, like the boy racers do :rolleyes: )
:)
 
Disco1BFG said:
^^^ another good reason for having decent gauges in place, so you KNOW what is going on under there;), then the ATF, and then the coolant. I'd suggest that its prudent to drive a tuned engine with some consideration if you want it to last..... and I do :)
Click to expand...

I've just noticed that there is a bit missing from this drivel :eek: = Eh?????? - it should have read:-

"^^^ another good reason for having decent gauges in place, so you KNOW what is going on under there;), I've noticed that the EGT's fall first, then the ATF, and then the coolant. I'd suggest that its prudent to drive a tuned engine with some consideration if you want it to last..... and I do :)"
 
Thanks for the input guys, I gave it a tweek yesterday, 2 turns on the smoke screw, moved the diaphragm around 90' and 1 1/4 turns of the star wheel.
I don't get any smoke at all which is good and I have a lot more power throughout the whole rev range, it's not sluggish like it was before. My EGT now reaches around 600'c on a long incline with my foot to the floor, maybe a little bit more but as soon as I take my foot off it drops very quickly back down to 400'c.
I'll be driving from Yorkshire to the south coast a few time In the next few weeks so I'll keep an eye on it and see how she handles on long runs and then adjust as necessary.
 
James_mac said:
with my foot to the floor
Click to expand...

Its only my opinion, but don't drive it like that - IME they won't take it when tuned - get a boost gauge too - and drive it on the limit of the boost - putting too much fuel in after max boost will just raise your EGT - and drastically reduce your MPG...:)
 
Disco1BFG said:
Its only my opinion, but don't drive it like that - IME they won't take it when tuned - get a boost gauge too - and drive it on the limit of the boost - putting too much fuel in after max boost will just raise your EGT - and drastically reduce your MPG...:)
Click to expand...

I don't drive like that all the time haha, I was just doing that like you said to get max boost and to try and max out the EGT. Iv got a boost gauge fitted so I was observing that too.
I measure my MPG every time I fill up so I'm going to keep an eye on that as well and if it's drastically reduced I'll wind it back a bit
[URL=http://s1049.photobucket.com/user/James_mac90/media/A4124CD9-DF38-4551-A2DE-53151FABCDB5_zpsejhzhges.jpg.html][/URL]

But she sits nicely at 70mph on the motorway now without stressing the engine too much which is good. It'll be interested to see what MPG im getting now but like I said above I'll be assessing that once iv put some miles through her.

The coolent and oil temps haven't changed at all, but the EGT is up on average around 100'c from what is was as standard throughout all driving conditions.
 
James_mac said:
What temperatures are you lot getting from your EGT gauges and how high can it safely go?

I rebuilt my 90 last summer and kept the fuel pump at its original settings so I think it's time for a tune up.
Iv got an alisport intercooler and a EGT gauge fitted on the EGR blanking plate, it's only a cheep one so I'm not sure how accurate it is, on a long incline with my foot to the floor I get around 500'c at a push, during normal driving it's normally around 2/300ish. How does that compare to everybody else?

I'm going to adjust then smoke screw, diaphragm and star wheel soon and monitor my EGT so I don't cause any damage, anybody know what temp not to go past and the average temp for a tuned pump.
Click to expand...

Advice: Leave it alone. It's an old tractor. You'll stuff something in the long term. Guaranteed.
 
James_mac said:
What temperatures are you lot getting from your EGT gauges and how high can it safely go?

I rebuilt my 90 last summer and kept the fuel pump at its original settings so I think it's time for a tune up.
Iv got an alisport intercooler and a EGT gauge fitted on the EGR blanking plate, it's only a cheep one so I'm not sure how accurate it is, on a long incline with my foot to the floor I get around 500'c at a push, during normal driving it's normally around 2/300ish. How does that compare to everybody else?

I'm going to adjust then smoke screw, diaphragm and star wheel soon and monitor my EGT so I don't cause any damage, anybody know what temp not to go past and the average temp for a tuned pump.
Click to expand...
With that Intercooler you're supposed to tune the pump.
 
James_mac said:
I don't drive like that all the time haha, I was just doing that like you said to get max boost and to try and max out the EGT. Iv got a boost gauge fitted so I was observing that too.
I measure my MPG every time I fill up so I'm going to keep an eye on that as well and if it's drastically reduced I'll wind it back a bit
[URL=http://s1049.photobucket.com/user/James_mac90/media/A4124CD9-DF38-4551-A2DE-53151FABCDB5_zpsejhzhges.jpg.html][/URL]

But she sits nicely at 70mph on the motorway now without stressing the engine too much which is good. It'll be interested to see what MPG im getting now but like I said above I'll be assessing that once iv put some miles through her.

The coolent and oil temps haven't changed at all, but the EGT is up on average around 100'c from what is was as standard throughout all driving conditions.
Click to expand...
Where them gauges from? Looks brillyant!
 
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