Juddering Clutch Brava/Bravo

Bravas/Bravos can be known to develop a juddering clutch and diagnosing the root problem is not always simple. I’ve heard cases where different mechanics diagnose different things for the same car; clutch, fluid, engine mount, tracking issues are all worth a mention. It could be any of these, but some are inter-related.

If I was to guess I would go with Clutch – over time the springs in the clutch get fatigued, loosen and cause a judder. it’s always worth checking the engine mounts also, as these can deteriorate (because of the judder in the clutch).

A good place to go for more info on fiat issues is:

http://www.fiatforum.com/bravo-brava/

 

 

Honda Jazz Juddering Problem and CVT Fluid Flush

My wife drives a Honda Jazz.

When you stop and start again (e.g. at a traffic light) it judders for a couple of seconds as you accelerate.

After speaking to a Honda Mechanic I know (along with some googling), it turns out this is a common problem! Some people have suggested trying to get this done by Honda as it was a known issue and Honda extended their warranty on it. The only problem with this is that Honda will charge you to diagnose, and if (BIG if) they find it’s due to the CVT factory fault, they will fix and refund for your diagnosis cost. I decided not to go down this route as I don’t trust dealerships as a rule.

From my research, the first course of action to fix this yourself is a ‘proper’ CVT Fluid Flush. (CVT stands for continuously variable transmission, something which Jazz’s have, so beware when changing/topping us your transmission fluid – it’s not your normal atf fluid!)

So back to the CVT Flush. The honda mechanic mate advised me once is not enough and you need to drain the fluid, fill and then drive and ‘burn’ the clutch; not to death but enough to get those crappy particles out. How you burn the clutch on this automatic jazz i am not so sure, but i think it’s a case of hitting brake and accelerator together at around 20-30mph.

After you’ve done the first change, do it again. then drain, and then fill the fluid.

I’ve not had my mechanic do this yet, so will keep posted and I’ll let you know how it went!

UPDATE: My mechanic changed the fluid twice and tried the above but it did not cure the problem. So, I took it to my local Honda dealership in Nottingham…

Honda were great. They initially gave me a price of £200 but I managed to haggle it to £150. They picked my car up from my work, and picked me up when it was ready and best of all?

It fixed the Juddering problem. So my advice if you have a juddering Honda Jazz? Bite the bullet and get Honda to fix it. (not often I say this, but sometimes it’s better to go with the dealer)

 

 

 

BMW E36 M3 Spark Plugs

The BMW E36 M3 produced between 1992 and 1999 had two different six cylinder engines fitted during its lifetime:

  • a 3.0L version S50 B30    (1992–1995)
  • a 3.2L version S50 B32    (1995–1999)

OEM (original equipment manufacturer) Spark plugs used by BMW in these engines were of two different types:

Original BMW part number for spark plugs: 12129069048

Upgrading to Iridium spark plugs

Some M3 owners, especially those who race or use their M3 on the track frequently have upgraded from the original spark plugs to Iridium plugs, with the NGK IX Iridium BKR6EIX being particularly popular among performance enthusiasts.

The main advantages in using Iridium plugs are that they last longer than normal copper or platinum coated plugs. They also have a finer tip which allows a hotter spark to be produced using the same current, which provides increased conductivity and improved anti-fouling of the plugs, leading to better fuel efficiency and better overall performance.

Changing spark plugs on a BMW E36 M3

The BMW M3 service manual recommends plug changes every 30,000 miles or 24 months as part of the Inspection II maintenance program.

How to replace the spark plugs on your BMW E36 M3:

  • First, remove the 2 round caps on the engine cover to access the 2 X 10mm nuts holding it in place
  • Remove the 2 X 10mm nuts and unscrew the oil filler cap in order to take the trim cover off
  • Put the oil filler cap back on – to avoid any contamination of the oil
  • Remove each ignition coil by prising up the flat metal clip and removing the two bolts which hold each electrical lead in place
  • Each coil is specific to each cylinder, so make sure you reinstall them as they were originally
  • Remove each plug with a spark plug wrench or socket wrench – check each plug for wear or abnormal residue
  • Before inserting the new plugs you can apply some anti-seizing compound on the thread

Difference between Clutch Bearing and Clutch Concentric Cylinder

It is becoming more common nowadays to come across what is known as a clutch concentric cylinder in both private cars and commercial vans and trucks. The clutch concentric cylinder is simply a slave cylinder fitted around the gearbox shaft, which does both the jobs of the traditional clutch release bearing and clutch slave cylinder.

A clutch basically disengages or isolates the drive power from the engine to the vehicle wheels momentarily while a different gear is selected. This avoids the damaging grinding together of gear cogs and provides for a smooth gear change. The clutch also allows your vehicle to stop without killing the engine.

The typical components of a traditional clutch are:

  • clutch pressure plate or clutch cover
  • clutch plate
  • clutch fork
  • clutch cable or hydraulic system and clutch bearing
  • clutch flywheel

A clutch concentric slave cylinder operates immediately in line with the clutch pressure plate and allows hydraulic pressure to be transmitted to the clutch through the clutch master cylinder and then the clutch concentric slave cylinder. The advantage of using a concentric slave cylinder is that less pressure is required from the clutch pedal, and it eliminates the possibility of the traditional problems associated with excessive bearing travel due to normal wear and tear with the old link or cable systems, and being a self adjusting system it can help prolong the life of the clutch.

This system basically eliminates the need for the traditional clutch bearing and clutch fork.

It is now considered good practice to replace the concentric slave cylinder at the same time as the clutch requires replacing to avoid possible damage to the new clutch and to avoid any unnecessary further expense and time later to replace only the cylinder.

Other advantages associated with the use of a concentric clutch slave cylinder include:

  • overall weight reduction (due to less components)
  • longer service life (because of less moving parts)
  • less prone to be affected by other external influences
  • reduced maintenance costs.

Diesel Fuel Filter Water Trap

The purpose of a fuel filter is to make sure that only clean fuel enters into the engine to be burned. Both petrol and diesel engines use fuel filters, however, in a diesel engine it is critical that the fuel is filtered for contaminants before entering the engine and for water to be filtered out to avoid any possible damage to the engine. This is not the same in the case of petrol engines.

This is why a fuel filter with a water trap is commonly used in private and commercial diesel engines. Typically the filtering of contaminants and water is done within the same fuel filter unit. The filter may have a bowl shaped reservoir at the bottom where the water will gather, as water is heavier than diesel.

The water then has to be removed, and this is normally achieved by using a valve at the bottom of the reservoir so the water can be drained away leaving just clean diesel fuel.

In many modern cars and commercial vehicles, sensors and electronic valves are used which drain the water automatically once it has reached a certain level in the reservoir of the filter.

Water contamination can be caused by a variety of things such as condensation which gathers inside the fuel tank due to humidity or temperature changes. As fuel is normally fed form the bottom of the fuel tank, and water is heavier than diesel, it means that the water will be sucked up first when you start your engine in the morning.

Typical sign of water contamination in fuel are when your engine runs rough, or idles with an uneven rhythm or loses power. This could be caused by either solid or water contamination but you should drain any accumulated water from the fuel filter water trap first or completely replace the fuel filter.