Advice on 300tdi auto issue please

Hi everyone

my disco is 300 tdi auto 96 on a P plate.

I have had auto serviced with oil and filter by local specialist in November 2011 when i bought the car, i have de egr and de cat serviced the car as in oil filters inc fuel sedimentor and also had inter-cooler off and cleaned out, new standard hoses and changed coolant, all is fine drives well and on recent trip to wales towing a 1.8ton twin axle caravan the car performed brilliantly for a 16 yr old motor.

Only prob was almost at the end of the 3.5hr tow after going up a short but steep incline the auto overheat light came on so i pulled up asap and waited for it to go out, it did after a couple of mins so set off again no probs until next incline and it came on again, so pulled up a couple more times and got to camp site no real probs. checked oil all ok not burnt or smelling and was fine all holiday.

coming back all fine until an hour or so in to the tow and reached first very long gradual climb on A44 out of aberystwyth towards newtown and before getting to top light on again so let cool asap, happened couple more times about 10 mins after on another long climb but then for the next couple of hours back to the midlands no probs, even on the motorway where the M54 pretty much climbs slowly for at least 20 mile ,no probs at all. i figure on the motorway i was able to get higher constant speed so had more airflow over the cooler? maybe?

So i was reading on an aussie forum that they fit RR p38 auto coolers instead of the 300tdi factory one and have solved the heating prob when towing, has anyone done this and if so is it an easy fit?

I am thinking it could be fit in front of rad(no a/c on mine) and just spliced into existing cooler pipes as you would an aftermarket cooler like hayden or mocal fit their kits? any reason why not?
do i need to get all complicated with land rover type fittings and if so why when all the aftermarket ones as mentioned just 'splice into original pipes?

Sorry for long post but trying to give as much info as i can

Many thanks for any help
Gaz

Not had any problems with mine but just for your info the original auto oil cooler is in front of the rad and any air con bits so should be easy to change.

gaz8885 said:

Hi everyone

my disco is 300 tdi auto 96 on a P plate.

I have had auto serviced with oil and filter by local specialist in November 2011 when i bought the car, i have de egr and de cat serviced the car as in oil filters inc fuel sedimentor and also had inter-cooler off and cleaned out, new standard hoses and changed coolant, all is fine drives well and on recent trip to wales towing a 1.8ton twin axle caravan the car performed brilliantly for a 16 yr old motor.

Sorry for long post but trying to give as much info as i can

Many thanks for any help
Gaz

Click to expand...

Hi Gaz, so you have an occasional over-heat problem with your autobox?

Here's the first things I would be doing before spending real money:

1. Check the autobox oil level. Yes I know you had it replaced recently buy the "specialist" but you wouldn't believe the number of times I've come across autos with oil level problems after specialists have worked on them.

This is the one and only procedure to adopt when checking the oil level in a D1 autobox:

"Commence procedure with a cold engine. Start engine, cycle the gear lever through all positions, dwelling two seconds at each one. Once you get to "1" go back up through all positions, to P. LEAVE THE ENGINE RUNNING; now got to the engine bay and withdraw the autobox oil dipstick they are usually reddy-brown in colour and just below the fuel filter.

Clean the dipstick with paper towel and fully insert into it's tube and withdraw again, the oil level should be between the two marks.

If it's not, it needs attention - go and check and report back.

Cheers
Dave

Hi biglad

I will check when cold, in the morning and report my findings

Cheers

hi

biglad, i checked the oil this mornung and i found that it was not smelling and is still quite bright red, not dark or brown, but to my dissapointment in the so called specialist who did the service it was just on the low marker!

It has no leak that i have come across since the box was serviced so i am blaming him for the low level. Lesson well learnt .. dont trust em check the jobs done!

Anyway i have topped it up with dexron 3 but i am still going to fit a bigger cooler just for peace of mind really as i want to try and avoid major probs if poss

Any ideas on a cooler? i am thinking mocal 13/ 15 row job


gaz

gaz8885 said:

hi

biglad, i checked the oil this mornung and i found that it was not smelling and is still quite bright red, not dark or brown, but to my dissapointment in the so called specialist who did the service it was just on the low marker!

It has no leak that i have come across since the box was serviced so i am blaming him for the low level. Lesson well learnt .. dont trust em check the jobs done!

Anyway i have topped it up with dexron 3 but i am still going to fit a bigger cooler just for peace of mind really as i want to try and avoid major probs if poss

Any ideas on a cooler? i am thinking mocal 13/ 15 row job


gaz

Click to expand...

Hi Gaz, as you will have found,with the procedure done and the engine still running it only takes 0.25ltr to go from low to high marks, so not to worry there.

Re and additional cooler I've never had the need to fit one so I couldn't advise on that - however I would say that there is a driving technique for reducing the workload on the torque converter, which is where most of the heat comes from.

When I'm towing I tend to use lower gears than if I was running without a load. So if I'm towing with an autobox car and the load is for example 2 tons all up, I will use 3rd gear a lot more, rather than leaving the gearbox in D. Why do I do this?

Imagine that you are driving a manual box car and towing - would you leave in 5th gear and slug it out at low revs? No of course you wouldn't, you would want to find a happy medium where the engine is operating is it's best rev range for a TDi it's between 2500 and 3000rpm soit can tackle hills easily. This probably means running in 4th gear for a lot of the time.

Exactly the same applies to the autobox. Instead of selecting D and leaving it there all the time, select 3 when you first start off. The 'box will automatically start in 1st and go through 2nd to 3rd and you can run around like that all day.

Won't it use more fuel? No, because the load, the gear ratios and engine torque are all working in harmony you may find you use less. You will also find that the TC doesn't need to work so hard so heat-generation is reduced.

Try it out and see how you get on.

Biglad,

Thanks for that, I have been reading a few posts about the use of the 3 option rather than D and forget the gears, its makes sense really.

I am going to fit a cooler, not sure which one yet, will post details when i get one, be a couple of weeks prob, then will try the gearbox in 3 next time i tow at the end of july, just so happens were going back to same place with same load pretty much so i should have a direct comparison re the behavior of the box.

will keep this post updated as things progress

Thanks again for your reply's

Gaz

untill locked t/cs produce heat ,heat is a result of transfering energy by the impetus of oil

sorry for the hijack. but it is relevant. i have searched but inconclusive.
so does the t/c lock up at a lower speed if only 3rd is selected?
will try to find out myself at the weekend.

xat44 said:

sorry for the hijack. but it is relevant. i have searched but inconclusive.
so does the t/c lock up at a lower speed if only 3rd is selected?
will try to find out myself at the weekend.

Click to expand...

Not on a DI Tdi 300, but on DII TD 5 it does work on 3 as well as D

When I first had my Disco the autobox warning light used to come on occasionally when towing up hill.
It turned out that the wires for the sensor were frayed from rubbing on the power steering pipes. After fixing that I never had another problem with it (with the light that is, I had all sorts of other problems with it).