96 Mk3 1.4 AEX Heavy breathing - Mods & Fixes

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Joined: Sat Nov 10, 2018 2:02 pm
Drives: 1996 Golf Mk3 1.4 AEX 5

96 Mk3 1.4 AEX Heavy breathing - Mods & Fixes

Postby Marco3_1.4 » Sat Nov 10, 2018 2:22 pm

96 Mk3 1.4 AEX Heavy breathing - Mods & Fixes

Odometer displays 60,000 Km
This hardly seems likely, but the drivers seat is in perfect condition, and the steering is shockingly precise.

These two features tally with the mileage, but not the engine.
The engine crankcase is blowing smoke into the air filter box.

Maybe it was just badly run in, and the bores are glazed ... or perhaps the piston rings are gummed up?
Either way, the air filter was in bad shape, it being contaminated with oil.

The VW breather is very badly designed - situated right next to the filter element.
Here is the motor type:


The Air Filter Box Mod

I found an elbow pipe, made a spacer, and two part epoxied the mod to the airbox, then added a silicone hose to lead the fumes to the air intake.
By adding a spacer, the breather valve was kept in place - it presumably is meant to catch the oil particles.

The elbow is slightly over 90 degrees, so this also might help catch the oil, allowing it to fall back into the sump.

However, any oil droplets that make it through the hose, will fall short of the air inlet, and should gather safely in the airbox base.


Air Filter Box Mod in Action

Here is a video of the working mod:
As you can see, it is smoking quite badly, and the condition of the airfilter tells the tale.
But at least the breather routing is an improvement over the original.

Now it is time to start thinking about ameliorating the breathing problem...

Trying a Snake Oil Fix

I had a bottle of Redex Petrol Injector Cleaner from the 90's.
From the smell, it seems to be diesel based, and presumably is chock full of detergents.
They state that 20ml per 10Lt of petrol and a full tank used will clean the injectors.

I figured that it could do no harm to stick some in each bore.
If the rings are gummed, then this might help loosen them.

I mixed around 20ml with a bit of paraffin and petrol, to thin it down, and shared it between the pots.
It's now soaking.

Tomorrow, I'll refit the plugs, and spin the engine over a bit, to allow the compression to force the oil between the rings
... then let it sit for a few days.

Obviously, I'm not hopeful, but it might make a reasonable video.

What do you think?
Place your bets

Internal Engine Steam Clean?

By this I mean, dripping water into the air intake when the engine is running and hot.

Has anybody tried this?
Is there any reason not to attempt this method on the AEX setup?

Obviously I'm aware that the engine would likely benefit from a strip
... but I don't particularly want to do that as there are plenty of other jobs to be done, and anyway, it is certainly interesting to see if the problem can be solved using other means

Posts: 3
Joined: Sat Nov 10, 2018 2:02 pm
Drives: 1996 Golf Mk3 1.4 AEX 5

Re: 96 Mk3 1.4 AEX Heavy breathing - Mods & Fixes

Postby Marco3_1.4 » Wed Nov 14, 2018 6:39 pm

After 4 days soaking in Redex Petrol Injector Cleaner, the desired objective was that the rings would loosen up (if they were stuck in the first place).

There was around 2.5 litres of 95 Octane petrol in the tank.
I added around 4.5 litres, with a 20ml dose of Redex, and 350ml of acetone (for a 5% mix overall).

The latter was in preparation for the steam cleaning, but adding Acetone is always a huge morale (performance) boost.


This detergent packed (diesel) addative, is anyway going to be a useful cleaner.
20ml was slightly over the recommended dose, but I don't believe that is anyway problematic.

I also added 20ml to the oil.
This was slightly wayward, but I judged that it would not be overly detrimental to the oil, and that it would add a pack of detergents, in preparation for the steam cleaning.
(also note that this oil is not for long term use ... it is the oil that came with the car).

As it happens, I probably shouldn't have bothered, because the Redex soak had soaked ( ) through, and into the sump.

Hey! ... those damned lifter oilways had better clear


This is God's gift to perfomance nuts, and a saviour when an engine is running badly.
It has a lower energy coefficient to petrol, yet it boosts every engine metric.

From a financial perspective, the major gains are from simply adding a very small amount ... 2.5% is sufficient, and therefore highly cost effective.
The only bummer is 'carrying it' and 'adding it'.

My guess (it's only a guess), is that the main component of Shell V-Power is acetone.
... but you pay a shed load of money for the convenience of not having to add it yourself.

From lab testing, we know the results from acetone doping.
The reasons for improved fuel burn efficiency are down to engineering logic.

    The fuel surface tension is broken - thus allowing perfect atomisation, to gain complete combustion of the hydrocarbons.
    My conclusion is:
    Because we see a major jump in total burn, with only a tiny percentage added ... this is the primary cause.

    Acetone has a slightly longer burn time - carrying with that burn, any remnant pockets of hydrocarbons.
    My conclusion is:
    This reflects the improvement in fuel burn efficiency, according to the doping percentage increase.

    Acetone carries oxygen - delivering oxygen at the point of combustion.
    My conclusion is:
    This reflects the improvement in fuel burn efficiency, according to the doping percentage increase.

From this, we have our explanation
... as to why, when we add a lower energy fuel, we get a higher energy output (and dramatically reduced emissions)

Current Phase Results

So far, there has been no improvement to the piston ring 'blow by'.
IE. the breather is still smoking like a chimney.

I took it for a run
A relatively short blast of a few kilometers.

The air filter was not fitted (the breather was open), and with the acetone mix, I was mindful of the increased combustion temperature, added to the lean condition without an air filter.

I kept it in second gear, and took it to the red line @ 5k.
Obviously it went like shooter off a stick ... an entirely different beast.

On return
Most of the exhaust fume stink had gone ... hahaha the rear silencer pipe was dry.
Great fun, and great for morale, even if this was expected.

Hard to say if the lifter tapping has been cured, because it was so hot.
I'll find out on the next start, and report back.

Clearly, there is much more to do.
We shouldn't be too downhearted about the Redex fail (on the piston rings)... it's an injector cleaner ... it was just a forlorn hope (at best).

Steam cleaning is next
... and fresh oil.

The rings/glaze problem might gradually clear up by themselves (hahaha some hope)
... but let's continue with the renovation process first.
(and a 1 to 10 acetone mix will probably get any bad engine through an emissions test).

Other Stuff

One of the plugs was knackered.
Here you can see before and after cleaning.

How this pot fired is beyond me.


Here it is after cleaning

You can see that the ceramic insulator is completely split in two.


Three Pole Plugs
These are hardy beasts, so I'm only ordering one.
They are fairly expensive over the counter, so I'm buying it from the UK at £3.85.
I'll bull up the order with a couple of oil filters and an air filter ... we need them.

The Air Filter Mod Video - How to make it

Link below.
It is definitely a good mod, regardless of a heavy breathing engine, so maybe it's worth a thumbs up (if you wish).

Here is the thumbnail (which you won't see with direct access).
It highlights the filter pollution - note the filter contamination on the nearside of the photo!


Video Link


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