2.5 TD 4WD first time overheating

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Re: 2.5 TD 4WD first time overheating

Post by umbongocat » Thu Jun 10, 2010 6:28 pm

mikexgough wrote:
umbongocat wrote:
missfixit70 wrote:Glad you got sorted, re the fuel consumtion, motorway driving could be anywhere between 25-35mpg realistically, @14 gallons if you ran it dry, equates to somewhere between 350-490 miles, but you could still have 2 gallons (@9 litres) in the tank when the gauge reads empty.
Best way to get an idea of mpg is to brim it, zero the tripmeter, run the tank down the when you refill take a note of the amount in against distance travelled, do this a few times to get a decent average, trying to guesstimate by the fuel gauge will produce nowt useful.

Really! We're still only getting 200 to a tank. We've never actually run it dry though, the the pointer is sitting on empty :(
I did 340 miles round trip to Wheelquick and Back yesterday...... and still had 1/3 tank left when I got home......been out today and still not at 1/4 tank.... 8)
eeek! Maybe we've still got something wrong then :( What kind of mph are you doing on motorway driving?
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Re: 2.5 TD 4WD first time overheating

Post by mikexgough » Thu Jun 10, 2010 6:36 pm

umbongocat wrote:

Really! We're still only getting 200 to a tank. We've never actually run it dry though, the the pointer is sitting on empty :(

I did 340 miles round trip to Wheelquick and Back yesterday...... and still had 1/3 tank left when I got home......been out today and still not at 1/4 tank.... 8)
eeek! Maybe we've still got something wrong then :( What kind of mph are you doing on motorway driving?[/quote]

I guess it depends on road conditions and speed..... yesterday I was towing my trailer too..... so 60 mph..... then you have to "stage" your moves when it comes to overtaking wagons.... you know the score.... overnight..not traffic is entirely different of course.... :wink:
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Re: 2.5 TD 4WD first time overheating

Post by umbongocat » Thu Jun 10, 2010 6:50 pm

mikexgough wrote:
umbongocat wrote:

Really! We're still only getting 200 to a tank. We've never actually run it dry though, the the pointer is sitting on empty :(

I did 340 miles round trip to Wheelquick and Back yesterday...... and still had 1/3 tank left when I got home......been out today and still not at 1/4 tank.... 8)
eeek! Maybe we've still got something wrong then :( What kind of mph are you doing on motorway driving?
I guess it depends on road conditions and speed..... yesterday I was towing my trailer too..... so 60 mph..... then you have to "stage" your moves when it comes to overtaking wagons.... you know the score.... overnight..not traffic is entirely different of course.... :wink:[/quote]

We were doing 70ish sometimes 80ish and getting 200 miles to the tank on the M4 and it was clear. Should we be getting more then? Or maybe when the pointer is on empty we still have a few miles left in it. We're scared to run it dry in case the light doesn't come on and we really do run out of petrol... which would be our luck!
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Re: 2.5 TD 4WD first time overheating

Post by haydn callow » Thu Jun 10, 2010 7:01 pm

What light ??
What you need to do is...
Fill the tank to the brim.
That will be 60 liters in the tank (I think)
Run it down to empty on the needle (200 miles)
Then go and fill up to the brim.
Deduct the amount you just refilled from 60.
This will tell you how many liters you have in the tank when ..
a....you have done 200 miles
b....when the needle reaches empty.

Then lets assume you put in 40 liters
You have 20 liters left or about 100 miles.

Simples ??
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Re: 2.5 TD 4WD first time overheating

Post by umbongocat » Thu Jun 10, 2010 7:05 pm

haydn callow wrote:What light ??
What you need to do is...
Fill the tank to the brim.
That will be 60 liters in the tank (I think)
Run it down to empty on the needle (200 miles)
Then go and fill up to the brim.
Deduct the amount you just refilled from 60.
This will tell you how many liters you have in the tank when ..
a....you have done 200 miles
b....when the needle reaches empty.

Then lets assume you put in 40 liters
You have 20 liters left or about 100 miles.

Simples ??
Thanks, we've been writing down mileage, litres and cost every time we fill so I'll go and do the calculations :)
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Re: 2.5 TD 4WD first time overheating

Post by missfixit70 » Thu Jun 10, 2010 7:58 pm

haydn callow wrote:What light ??
What you need to do is...
Fill the tank to the brim.
That will be 60 liters in the tank (I think)
Run it down to empty on the needle (200 miles)
Then go and fill up to the brim.
Deduct the amount you just refilled from 60.
This will tell you how many liters you have in the tank when ..
a....you have done 200 miles
b....when the needle reaches empty.

Then lets assume you put in 40 liters
You have 20 liters left or about 100 miles.

Simples ??
Bear in mind you don't want to run it empty & it'll start sloshing around with around 5 - 10 litres left.
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Re: 2.5 TD 4WD first time overheating

Post by paulandyt » Thu Jun 10, 2010 9:21 pm

200 miles seems a bit low? What engine do you have? Is it a standard bongo or camper conversion?
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Re: 2.5 TD 4WD first time overheating

Post by haydn callow » Thu Jun 10, 2010 9:31 pm

If you were only getting 200 miles on a tankful you are doing 15MPG....that is dreadful and probably wrong.......that would be the result of having the exaust recycling valve shut and if that were the case the performance would be seriously affected.
I would say your gauge is misreading and when you reach empty you probably have 20 plus liters left.
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Re: 2.5 TD 4WD first time overheating

Post by missfixit70 » Thu Jun 10, 2010 9:35 pm

As has been said so many times, check the amount that it takes to refill a previously brimmed tank against the mileage, going by "tankfuls" is meaningless, especially if the gauge ain't reading right.
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Re: 2.5 TD 4WD first time overheating

Post by umbongocat » Fri Jun 11, 2010 12:00 pm

paulandyt wrote:200 miles seems a bit low? What engine do you have? Is it a standard bongo or camper conversion?
It's a camper conversion, 2.5 4wd but I've got to check it again the way misfix and Hayden have suggested and then will post back the proper mileage it's getting to the tank :)
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Re: 2.5 TD 4WD first time overheating

Post by mikexgough » Fri Jun 11, 2010 1:02 pm

paulandyt wrote:Hi Mike, I did questions whether it could have been an air lock while they explained what they did to it, they couldn't say, but it sounded plausable to them.
Cheers all!
I guess we will never know for sure as to what "held" the coolant level in the system, so as not to drop, while it was hot but an air lock could probably be the answer from your description. Thanks for the feedback, it kind of answers what I thought
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Re: 2.5 TD 4WD first time overheating

Post by bigdaddycain » Sat Jun 12, 2010 10:51 pm

Mine's a 1995 4WD 2.5 turbo. The last time i did an "economy run" (if ya can call it an economy run in a bongo!) I saw an average of nearly 34 MPG. But that was with me TRYING to be as economical as possible with my fairylike dainty size 12's! Mixed running without particularly trying i'm looking at about 360 miles per tank.... Economy plummets above 65MPH, shame really as the bongo sits comfortably at 85MPH, not so comfy on the wallet though!
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Re: 2.5 TD 4WD first time overheating

Post by bigdaddycain » Sat Jun 12, 2010 10:57 pm

mikexgough wrote:
paulandyt wrote:Hi Mike, I did questions whether it could have been an air lock while they explained what they did to it, they couldn't say, but it sounded plausable to them.
Cheers all!
I guess we will never know for sure as to what "held" the coolant level in the system, so as not to drop, while it was hot but an air lock could probably be the answer from your description. Thanks for the feedback, it kind of answers what I thought
I'm thinking along the same lines Mike.... Water leaking out, air leaking in, minimal displacement at the expansion tank. Hence no LCA warning until the level had dropped below the probe (as it should).

Perhaps a disclaimer should be submitted with LCA's to highlight that in certain cases the LCA won't always pick up on such a scenario, and is rendered redundant in such a scenario? Contradictory of it's dubbed "engine saver" tag, this time it simply didn't save it.

Glad to hear you are back on the road, even if you are nearly £1500 lighter! That's almost a tank of fuel!!! :shock:
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Re: 2.5 TD 4WD first time overheating

Post by missfixit70 » Sat Jun 12, 2010 11:13 pm

The airlock scenario has been discussed on here for years, Haydn came up with the high level add on, that should & did detect the airlocks in my case recently, but he had virtually no take up on the high level add on.
"Engine Saver" is just a trade name based on what it can do, if you buy Shell fuel do you expect to get a tank full of shells? or if if you buy "Star Drops" detergent do you expect it to be full of stars? :wink:
It's called a low coolant alarm, it detects low coolant, it has it's limitations as does anything, but if the coolant drops it picks it up. I would always recommend fitting the LCA & Mason alarm as a minimum, as that covers most eventualities, BUT still not all, that would be virtually impossible/cost prohibitive.
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Re: 2.5 TD 4WD first time overheating

Post by Northern Bongolow » Sun Jun 13, 2010 12:39 am

if you read the first post it is said the coolant alarm did not go off,just high temps were noted!! no coolant lost,this does not point to a coolant issue to me.the head gasket could be failing at this point through a variety of reasons,and in different ways.it could be leaking engine gasses into the oil side and noteing temp increases that way,this could cause the coolant temp to rise and the expansion or rap cap to weep,but under pressure the coolant will still be fighting to keep the system cool,note the slight increase noted later.when in the morning the system has cooled and the coolant level dropped(normal)you would have to top up a little(alarm activated)
sounds a little more plausable than just inventing an airlock cause that maybe was never there in the first place.
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