Early 1.9 to 2.1 conversion - stop me if I'm being stupid!

[itchyfeet]

How much extra oil for the cooler and how do you drain it at oil change?

[CJH]

How much extra oil for the cooler and how do you drain it at oil change?

Two very good questions. About a litre as far as I can tell at the moment - maybe a touch more. It'll make it over a can to do a change, but the extra volume of oil helps with the cooling I believe. For draining, those two unions under the coolant header tank are there partly to allow me to disconnect them for an oil change, and partly because the hose won't twist at all so they're needed to make the angled unions at each end angle in the right direction. But the cooler matrix itself takes forever to drain - I discovered that when I flushed it with fresh oil today, as I'd bought it second hand. So even with the van parked nose up, the oil hot, and the hoses disconnected it's going to take ages to drain. I might invest in another short length of pipe that I can connect to the disconnected hoses so I can blow through it.

Strictly speaking I think it would drain without disconnecting the hoses, because the sandwich plate is open all the time I believe, and all that happens when the oil hits 80º is the bypass closes, forcing the oil round the cooler. I've got a fair bit of Lidl 15W40 oil that I'm not going to use now, so I may use it just as a flush when I do an oil change. I've done this before, and its a good way to wash all the old black oil out so the new stuff stays clean longer.

[itchyfeet]

There will be thoose who tell you oil should be more the 80 degrees, more like 100, something to do with burning off nasties.

[CJH]

There will be thoose who tell you oil should be more the 80 degrees, more like 100, something to do with burning off nasties.

Yeah I've read that - 100º needed to boil off moisture for instance. It's tempting to give a glib answer and say that Mocal must have chosen 80º for a reason, but I guess it's possible their kit is designed for racing engines, rather than daily drivers. So I don't know, maybe condensation will take longer to be driven off at 80º. But on balance I'm quite happy to relieve the pressure on my cooling system, which is the aspect of the WBX that seems to cause the most problems - I know that my stress levels go up when I'm sat in traffic on a hot day, watching my temperature gauge rise, wondering if the fan's going cut in.

[weimarbus]

what size bore hose did you use for the front to rear hoses? I have mine in the rear left hand air vent at the moment with 1/2 inch bore but would prefer the front mount.

[CJH]

what size bore hose did you use for the front to rear hoses? I have mine in the rear left hand air vent at the moment with 1/2 inch bore but would prefer the front mount.

I don't remember I'm afraid - too late to measure the internal diameter now. They're stainless steel braided, I think PTFE, with crimped on fittings, and they weren't cheap. I'll measure the outside diameter tomorrow. I would have gone for the same mounting site as you, except that the brackets for mounting it at the front came with the cooler, and I worried about whether a rear mounted cooler could do much when the van was stuck in traffic - at least with the front mounted position it will benefit from the radiator fan. Silverbullet's thermostatically controlled fan on a rear mounted cooler seems ideal though.

[weimarbus]

Thanks for that, I think that the fan is indeed needed when in the rear vent as cooling is a bit hit and miss at the moment.

[CJH]

Thanks for that, I think that the fan is indeed needed when in the rear vent as cooling is a bit hit and miss at the moment.

I measured the outside diameter (17mm), then attempted to identify the hose from the website of the company I bought it from (Hydroscand). I think it's this one. That would make it 1/2" internal diameter.

[CJH]

I took the van to Busfest over the weekend, and it was nice to have a long run to get a feel for the new engine. 600 miles on the engine now and I'm really pleased. There's still plenty of pedal left when I get to a top speed that I'm happy with (an indicated 70mph, but closer to 65 in reality), and it pulls up hills better than the DG did. But it isn't a 'night and day' change I think - the character of the engine hasn't really changed, although the van feels somehow 'lighter'. Looking forward to giving it a good test up some proper hills.

As usual with Busfest, there was a long queue to get in, despite arriving fairly early Friday morning, and there were long queues to get back to the M5 yesterday, and at no point did my cooling system worry me. Makes a nice change. The fan came on and went off when I wasn't moving, but the needle stayed well to the left of where it would have been before I changed everything, and the oil temperature only nudged towards 90º a couple of times - most of the time the airflow over the cooler at the front was enough to keep the temperature at 80º.

The biggest surprise was when I filled up with petrol when I got home to check fuel consumption, expecting quite a hit given that it's a bigger engine with a carb that I'm assuming is running a bit rich. But actually there's no discernible change - I averaged my usual 23-and-a-half mpg over the 250 mile tankful.

[CJH]

... I averaged my usual 23-and-a-half mpg ...

... which we should all now know is 0.1202 mm^2.

[bigherb]

Not unusual for larger engine to have the same fuel consumption or better for the same work as it has to work less hard. It is when you use the extra performance it drinks more.

[CJH]

I'd heard that, but never really stopped to think what 'working less hard' means. Given that nothing has changed with respect to the road speed for a given engine speed, I guess it just means that I'm opening the throttle slightly less to achieve the same engine speed, courtesy of the bigger bangs. At full throttle there's obviously now scope to pump 10% more air (and therefore 10% more fuel to keep the mixture correct) compared to the 1.9 engine.

[bigherb]

I guess it just means that I'm opening the throttle slightly less to achieve the same engine speed, courtesy of the bigger bangs.

Yes that is basically it. Also larger engines are often higher geared which leads to the cylinders having to be filled less times in a mile.

[itchyfeet]

But it isn't a 'night and day' change I think - the character of the engine hasn't really changed
.

I think thats becuse the 2e3 won't give the extra air/ fuel you need.
My DJ pop top weight is 1700kg and is noticeably faster than the tin top DG at 1300kg

[weimarbus]

I'm glad that your engine is performing well, a very belated thank you for your measurements but we have been away doing what the camper does best, (relieving stress)