There are a few common problems
with the Renault 5 GT Turbo Blown Head Gaskets, Knackered
Turbos and Knackered Clutches all of which are pretty
expensive to replace and/or fix. Under each sub heading
I will mention how to maintain a 5 and keep these problems
to a minimum.
Head gaskets blow for a reason
for which there are two reasons either the Boost has
been turned up too much or the car has overheated. If
you are going to turn the Boost up either using a bleed
valve or adjustable Boost control on a standard head
gasket you can really only turn it up a little bit.
The Boost can be turned up by winding in the nut on
the wastegate actuator arm remembering the more you
wind it in the more Boost you will get out of the Turbocharger,
but this puts more strain on the headgasket, thus causing
it to blow. If you want to turn the Boost right up then
you are going to need an uprated head gasket to cope
with the added strain put on it. Also turning up the
Boost will make the Turbo work harder thus shortening
it's life span unless it's a hybrid Turbo manufactured
for running higher Boost.
Turbo
Boost
If you do turn the Boost
up above 15psi then really the fuelling needs to
be adjusted to pump in the correct ratio of fuel
into the engine by maybe using bigger carb jets
or a Group A carb. If you do not increase the fueling
to match the higher Boost then you will get "PINKING"
or "DETONATION" as it is called. This
WILL damage pistons which are expensive to replace
as the engine has to come out and the engine be
rebuilt. |
|
Bar |
PSI |
 |
A |
0.55 |
8.25 |
B |
0.65 |
9.75 |
C |
0.7 |
10.5 |
D |
0.8 |
12.0 |
E |
0.9 |
13.5 |
|
Another cause of a head gasket
to blow is the car overheating and considering that 5's
run hot as it is there really is no margin for error.
So if you're driving a 5 always keep a watchful eye on
the cars temperature gauge. Driving along a five should
read just below to halfway on the temperature gauge under
normal driving conditions and maybe rise a little on the
motorway and when putting your foot down where the Turbo
is being used alot. While sitting in traffic the Cooling
Fan should cut in just before the 2 3rd's line on the
gauge. If you notice that the fan doesn't cut in when
the temperature gauge gets to the 2 3rd's line switch
the car off and let the car cool down. "NEVER LET
THE CAR OVERHEAT" "NEVER LET THE CAR'S TEMPERATURE
GAUGE GET INTO THE DANGER ZONE AND WAIT FOR THE RED LIGHT
TO COME ON AS BY THEN THE DAMAGE IS PROBABLY ALREADY DONE"
You may have a dodgy thermostat or Fan switch which isn't
working properly which may be the reason the fan isn't
cutting in.
FOR THESE REASONS THE CAR'S COOLING SYSTEM ALWAY'S NEEDS
TO BE IN GOOD WORKING ORDER.
Maintaining
the Cooling System
Keeping the cooling system on
a 5 Turbo in good working order is a must. An £8
fan switch not working could cause your headgasket to
blow and/or warp your cylinder head and end up costing
you £400.
Temperature Gauge Guide
Maximum
driving along at a steady speed |
Maximum
Radiator fan cut in point |
 |
This
may rise slightly when driving the car hard, ie
using the Turbo alot. Idealy the cooler they run
the better so if yours run slightly lower than this
then its a bonus. |
 |
I
would not let a GT Turbo run much over this point
as it is likely to cause damage by warping the cylinder
head. |
On a regular basis
The cooling system on
the 5 gets air in it from time to time and this can cause
the car to overheat so to overcome this and get the air
out you do the following.
Click for a bigger
image
YOU REALLY
NEED 2 PEOPLE TO DO THIS
1. Unscrew the Coolant Tank cap and unclip the strap
holding it to the side of the inner wing and lift
it up as high as you can get it with all the pipes
attached.
2. On the top hose there is a plastic screw in the
top of it. Get someone to stand by this and undo this.
3. Now with you standing holding the Coolant tank
over the top of the wing and another person holding
the srcrew from the top hose put your mouth over the
top of the coolant tank making it air tight blow holding
in the pressure and not letting go. Keep the pressure
on until you see out of the screw hole pure coolant
flowing out with no air in it. While the coolant is
flowing out air free get the person to screw in the
plastic screw back in all the time you are holding
in the pressure. Once the screw is back in you can
remove your mouth from the coolant tank.
4. Now you need to follow the same procedure for the
screw on the top of the the pipe coming from the top
of the water pump and remove any air from this side
of the cooling system.
Once you have done the same for the water pump pipe
screw you can put the coolant tank back in place and
screw on the cap. Hopefully your Cooling system should
be free from any air locks.
Also on a regular basis
leave the car running and wait for the Cooling Fan
to cut in while watching the temperature gauge and
make sure that it cuts in where it normally does.
If it starts to go above the 2 3rd's line then switch
the car off and investigate what the cause is before
driving the car. Likely causes are air in the cooling
system, blocked radiator or cracked radiator, faulty
water pump, faulty thermostat, a hole in one of the
water pipes, faulty fan switch or incorect coolant
mixture.
Do not let the car overheat
Never let the car overheat
or let it get into the danger zone where the little
red light on the temperature gauge comes on. If your
in traffic and the car goes above the normal temperature
where the fan cuts in pull over and switch the engine
off. Call someone out and have the car towed home
or to a garage and investigate the problem before
driving it again.
Turbo
Failure
Because the
turbocharger on a Renault 5 Turbo is a small T2 Garrett
it spins up quickly,
partly the reason 5 Turbo's are so quick, but
this also means that they really are on the go all
the time that is why the life expectantcy of the Turbo
is roughly about a year. But there are a few things
that you can do to prolong your Turbo's life.
1. Change the oil regularly (Maximum every 6000 miles/Recommended
every 3000 miles). Because your engine oil is what
lubricates the bearings inside your Turbocharger and
if the quality of your oil is poor this is going to
have an effect on these bearings, thus causing them
to seize up (New Turbo Time NOT CHEAP £250 Recon
+ Fitting). So the rule is change your oil as often
as possible and use a high quality Engine Oil Semi-Synthetic
minimum.
2. Also you can prolong the life of your Turbocharger
by getting in the habit of every time you finish your
journey and want to switch off your engine, let the
engine idle for about 2 minutes then switch off the
engine. This allows the Turbo to stop spinning before
the oil supply to the Turbocharger is cut off by you
switching off the engine.
Another Factor that will
make your Turbo's life shorter is by turning up the
Boost (Meaning the Turbo spins at a higher RPM that
normal thus wearing it out quicker).
A Dump valve may improve
the life expectantcy of your Turbo though this may
only be true of hybrid Turbo's running higher Boost
im not sure. Any way the dump valve releases the pressure
left in the the inlet pipe when you release the throttle,
otherwise this pressure causes the Turbo to stall
and when you apply the throttle again it has to spin
up from start again causing Turbo lag. Where as if
you release the pressure via a Dump Valve the Turbo
keeps spinning and picks up speed again when you apply
the throttle after gear change. It doesn't neccessarily
make the car quicker or make the cars BHP figure any
greater but maybe give the Turbo a bit of extra life.
Fitting a dump valve
guide
Worn
Clutches
Worn clutches are a big
problem for the 5, because they're a common problem
and they are not cheap to replace. The reason being
because these cars accelerate so quickly it puts alot
of stress on the clutch. So having an uprated clutch
will be a better bet than the standard renault clutch
especially if you are running higher Boost. To have
the job done properly you are looking at around £400.
That is with the engine being removed. You can do
the job the same way as with other cars by just removing
the gearbox but because of the limited space chances
are that it will not be alligned properly so probably
won't last very long. So to make your clutch last
here are a few tips.
1. Do not ride the clutch as this will cause it to
wear.
2. Try not to rest your foot on the clutch pedal as
this could stretch the clutch cable or wear the thrust
bearing.
3. Sudden accelaration from a standing start all the
time will wear your clutch so if your game is traffic
light grand prix's then your probably best off having
an uprated clutch.
Rule of thumb with the
GT Turbo
This is where having a deep
pocket comes into it. If something goes wrong with
a 5 Turbo try to fix it as soon as possible because
before you know it you'll have another problem then
you'll find it hard to get back on top of them. Bottom
line is treat them like a baby as they can be very
temperamental cars when not treated right !