Getting to know my V6 but what is normal!

[stuart_indalo]

So every other post is about overheating. I bought a V6 to get away from the trip to the headshop..

When driving to work about 20 miles on dual carriageway I then drive into town with heavy slow traffic and I hear the front fans kicking in. If I stop at this point the bottom hose is still cool while the heater circuit is very hot with fans running. If I keep the engine running on tickover fans go off and bottom hose heats up v. hot as thermostat opens fully.

The coolant level is just below the full mark at cold today (I topped it up to full the other day)and some liquid is being vented out the tank. This morning I heard the fans coming on in town but as I drove around they went off and when I stopped the bottom hose was warmish. No great loss of fluid noticed but the top of the horn was wet with coolant. I bled the system last weekend 3 times and flushed through with fresh coolant and with the bottom hose heating up on tickover I think I have no airlock.....

So is it that as the van comes off the fast road there is a lot of heat which can be only be dissipated by the fans because the bottom of the engine is being cooled down on the road preventing the thermostat opening? There is no protective cover under the engine which might stop heat spreading around the engine and opening the thermostat earlier?

Garage did a pressure check and compression check for me and all was good. After my last bongo burst into a cloud of steam I want to make sure this one is right but can't believe that losing coolant out the tank, even small amounts is normal as is driving around with the fans going in temperatures of 3 degrees outside! Fans coming on before the thermostat opens seems counterintuitive too but maybe that is V6 bongo!

I have read everything I can on the cooling system, I think I understand the different circuits so everything seems right except the early fan cut in and the coolant leaving the tank...Maybe I had too much in it. I will keep an eye on it to see if it falls any further than just below full when cold.

So waiting for the replacement distributor and contemplating the grunching suspension on speed bumps. No its not the anti roll bar clamps sounds like it is higher up the struts. But right now I would settle for someone telling me my engine was behaving normally. I intend driving in Spain this year so really don't want any heat issues.....

[g8dhe]

I think you might find that the V6 is significantly different from the diesel, remember you haven't got the dual speed fans to start with in a V6 and with the covers off you will have disrupted the normal airflow altogether!

[stuart_indalo]

I have had a look for covers, I think it is just the main big one which is missing. I suppose a breakers may be the place for one.

[Simon Jones]

You mentioned 'the top of the horn' was wet: do the mean the horn under the headlamp? If so, it sounds like a leak from the radiator, or possibly a pin hole leak in a hose in that area. Silly question, but have you got the A/C on as that will switch the rad fans on.

[mikeWalsall]

I think you might find that the V6 is significantly different from the diesel, remember you haven't got the dual speed fans to start with in a V6 and with the covers off you will have disrupted the normal airflow altogether!

I am hard of hearing and have an hearing aid (old age) .. so i ma not a very good judge of what's what in the sound department .. so i was wondering what you mean by dual speed fans on the V6 ..

Do you mean on the two Rad diesels fans have independent lecky circuits ..??

I have the full under body trays on mine .. and have never heard (or thought) the fans come on while travelling ..

But I have noticed the fan(s) come on when turning on the A/C ..

When messing about on the drive .. I have noticed the scavenger fan 'kick in' .. but as far as I know not the two rad. fans ..

Is that 'normal' ..??

[g8dhe]

On the diesel the two fan motors have four (4) commutators / brushes they are powered up to give two different speeds as needed by the ECU;


On the V6 & 2l only standard two brush motors are used;


The separate fan is the scavenger fan on the left on the diesel circuit and on the right on the V6/2l

[stuart_indalo]

OK I may have mistaken the black object below the tank. Anyway the expansions tank vents via the hose and the black object below was wet, so no mystery over the source of liquid.

The A/C was off so that is not the cause. I have yet to check out the A/C but at these temperatures it will not be for a while yet.

[haydn callow]

The expansion should not vent if the level is at the full line cold......I would get the level correct and if it vents first try a new pressure cap.....if it still vents with a new cap you have a problem....

[haydn callow]

You should run your AC every month for a few mins to keep the seals lube,d

[stuart_indalo]

New cap on expansion tank and radiator! I am still pondering whether the lack of an undertray is exposing the underside of the engine to excessive cooling in this cold weather thus preventing the thermostat from opening sooner.

If I had an airlock the bottom hose wouldn't get hot when running stationary so no airlock presumably or could there be a bubble lurking in the engine? The water pressure test should have shown any fault in the head and compression was good.

Would a choked radiator produce these symptoms? Not sure where I go from here. I suppose I could replace radiator, thermostat and waterpump and see what happens but this is all beginning to sound like a drain on cash.....

[Jim the Box]

Stuart
It may be best if you can find another V6 owner in your area so that you can check your vehicle against the other. I have the large engine shield under my V6 and under normal running conditions in this weather the bottom hose on my bongo never gets hot, (although it is warm to the touch) the fans come on if the engine is standing idling after a while. You may have nothing to worry about on the temperature front, however I would be concerned if you are certain you are not overfilling the expansion tank and it is still discharging some of the coolant.

[stuart_indalo]

Thanks. I have decided to get the coolant checked for exhaust gases and have one more go at bleeding just to make sure.

Is the big cover the same as on the diesel? I can't find it on any of the lush projects diagrams.

[haydn callow]

I have a V6.......in 3 years the temp has only gone over 80C a handful of times.....towing in the summer.....it normally runs at about 75C so bottom hose never hot and stat stays closed. (I have 3 extra temp gauges fitted). Removing the tray would IMHO have little or no effect .....you could be worrying about nothing.....but the venting in the header tank defo needs investigating.....that is a worry.....venting is normally caused by combustion gasses

[teenmal]

I have a V6.......in 3 years the temp has only gone over 80C a handful of times.....towing in the summer.....it normally runs at about 75C so bottom hose never hot and stat stays closed. (I have 3 extra temp gauges fitted). Removing the tray would IMHO have little or no effect .....you could be worrying about nothing.....but the venting in the header tank defo needs investigating.....that is a worry.....venting is normally caused by combustion gasses

Hi,are you talking about engine casing temperature or coolant temperature.

Cheers.

[haydn callow]

I have one sensor inside the top hose where it exits the cylinder head and one bolted to each cylinder head.......once it all warms up they all read within 2C of each other.