Diesels Need Hammering?

[Hurricane]

Hey,

I often hear that a diesel car needs a good long run and blast, (in other words to hammer it). Thing is my Mum doesn't like BX's she would prefer a small city car and sadly she uses one of our BX's every day for little eronds to the supermarket, or to town, stop/start etc (usually the TZD).

Then when the weekend comes round and me and my Dad go for a drive the amount of smoke that comes out of the back when accelleratring is real bad, and we think it's all the crap that has built up over the week running eronds and not doing over 30 mph.

Anyone else had this with a BX? Will it cause trouble in the long term? And which would be the best car for short 30 mph runs at the moment, our 19 TXD or the TZD.

Thing is once the car has had a good run at the weekend, the smoke problem disspears and it drives beautifully, then it's back to short runs for the next week.

Martyn.

[MULLEY]

Small journeys arent ideal for any car to be honest, i would get her using the 19TXD instead of the turbo, purely because its a much less complicated beast & hence wear & tear on that one is more likely to be cheaper to fix.

A good run does clear out the crap like you say, but if short journeys are the order of the day then theres nothing you can do about it. Can you do some minor tinkering yourself? If you can then try below:

Change the oil more frequently than the 6000 mile schedule, replace the air filter & also the fuel filter. That will hopefully help a bit with smokey exhausts, it wont eliminate it, but should help a bit.

A good run once a week should sort it out though.

My more esteemed club members may have some better or alternative suggestions....

[Hurricane]

Cheers.

I'll look into that, I thought she should use the TXD as it's a lot slower than the TZD but I wasn't sure. Some cars are built for short runs though like little city cars and that is what she would like, although she's been lumbered with BX's all these years.

We want to keep them on the road as long as possible so we may look into another car for her.

Martyn.

[Barrie James]

I agree. We have both a TXD and a TZD. I use the TZD for longer runs and my wife uses the TXD for the short runs, with me occasionally taking it for a blast to clear the pipes.

I find it easier to drive the TXD around town as the gearing is lower, I find the TZD doesn't like town at all, I seem to spend all my time in 3rd gear, as she hates pulling anything under 32 / 33 mph in 4th.

If she wants a city car how about an AX diesel. We have a Memphis 1.5D, which is a good little runabout, and is pretty good on a run if you need to go further, including 60mpg+.

[MULLEY]

Are the gear ratios the same for all the TZD Turbo's? Mine was quite happy to be in 5th gear at the speeds you've mentioned Barrie.

Time to tell Mummy thats its the TXD or walkies

[ken newbold]

You coulld always do the really sensible thing and get her an auto. My Mum never wanted one but now she thinks it's the best thing she ever did, complete with Hurricane interior

[Philip Chidlow]

Dare I say ZX Turbo D - cheap and remarkably flexible: economical (you can run it with diesel/veg oil mix too) and GTi fast when you want it to be. And almost as cheap as a BX. Certailny more car for your money than an AX.

[jeremy]

I get a similar problem with my DTR Turbo which gets used in town for quite a lot of the time. I think most of the problem is the collection of condensation in the very large transverse silence - which might cause it to rot prematurely (Mine was last changed 7 years ago).

I don't think it'll cause any problems - and the condensation will clear when the exhaust gets good and hot - which is not easy as its about 7 feet from the engine and air cooled!


As a matter of interest our 1.9D ZX suffers in much the same way with visible smoke on hard acceleration especially after dark after prolonged town running. The ZX exhaust is just 2 small silencers.

[Kitch]

I had a 19RD. That definately needed hammering, otherwise you never got anywhere

But after a good long thrash (which was all it ever got) it never smoked. Brilliant engine.

[Way2go]

Change the oil more frequently than the 6000 mile schedule, replace the air filter & also the fuel filter. That will hopefully help a bit with smokey exhausts, it wont eliminate it, but should help a bit.
..

Why will changing the oil more frequently than 6000 miles help with a smokey exhaust Mulley? Dirty air filter could cause it to run rich yes, but fuel filter restrictions would cause the mixture to be weak if anything.
Surely the main problems with a smokey exhaust would be condensation build up of water and unburnt fuel in an exhaust system that is not regularly getting up to full working temperature. If the engine is not using oil then changing it more frequently cannot affect smoke and if its using oil, changing it can't affect smoke. In the latter case then rings or valve stem seals would need attention to improve matters.

[DavidRutherford]

This all boils down to soot and particulate matter.

A diesel engine... any diesel engine generates an amount of soot. If you drive the engine gently then this soot builds up in the exhaust boxes as the exhaust speed isn't high enough to blow it out. When you do then give it welly, the exhaust gas speed is high enough to blow out the accumulation of soot. This is precisely the reason why you drive a diesel car like you've hired it to the MOT centre.

The engine itself doesn't care whether you're pootling around town or belting down the motorway, as it's not the engine that fills up with soot (well, maybe just a little bit), it's the exhaust that matters. If you are concerned about soot build-up then I would recommend the lesser powered car for pootling around in town. Two reasons for that: 1) You have to work the engine a little harder to make the car move, thus increasing exhaust flow, and 2) The lesser powered car will have a smaller bore exhaust system, which means higher exhaust speeds for the same volume flow. Essentially the lesser powered car will keep it's pipe cleaner.

Contrary to belief, allowing the exhaust to soot up doesn't matter at all. As long as it's given a hoofing to clear out the exhaust before the silly MOT rev-test, don't worry about it.

[MULLEY]

Way2Go, i wasn't very clear, i wasn't meaning that changing the oil would reduce smoke, i meant as normal practice if doing lots of short stop start journeys, to reduce engine wear. Some people on here change the oil every 3k.

[Way2go]

Way2Go, i wasn't very clear.

No probs mate!

With oil changes though on branded stuff like Total, Castrol etc, I see no need to change at less than 6000 miles but if using El Cheapo it may be advisable. I don't know what brand the Doc uses but I believe he is in the 3000 mile club.

Newer cars now are not recommended for oil changes more frequently than 9 or 12000 miles but they of course are using fully synthetic oils.

[MULLEY]

I have started using semi synthetic oil on the 19txd, it does seem to make it a bit quieter & hopefully a little bit more economical & reduce engine wear as well.

Can you use fully synthetic oil to increase the oil service interval?

Sorry slightly off topic....

[Way2go]

Can you use fully synthetic oil to increase the oil service interval?....

I guess you could BUT there are side issues with regard to gasket integrity etc which could cause an otherwise good leakproof engine previously running on mineral oil to leak when using synthetic due to the superior cleaning ability of the oil.

If the engine was rebuilt using new gaskets then probably OK.