AlbumAlbum  CalendarCalendar  FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 MapMap  ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 
MK1OC Club Membership
MK1OC Club
MK1OC Chat Room
Contact MK1OC by Email
Purchase Stickers

:: best viewed @ 1024 x 768 :.

Neil Andersons Mk1 Astra Guide

Post new topic   Reply to topic    MK1 Astra Owners Club Forum Index -> Hints & Tips
View previous topic :: View next topic  
Author Message
Club Manager
<font color=yellow>Club Manager</font>

Joined: 17 Mar 2005
Posts: 2095
Location: Chelmsford

PostPosted: Sat May 28, 2005 10:47 am    Post subject: Neil Andersons Mk1 Astra Guide Reply with quote

All of this is based on my personal experience; therefore I cannot be responsible for any damage, etc caused by using this information. Always consult a service manual before attempting any work.

These are things that I have personally come across and are my own opinions. If you find any of this incorrect or know of a better method please pass it on. Any comments will be gladly received at

Bodywork and Chassis:

As most people are aware Vauxhall tended to use old baked bean tins to make their cars out of. This of course proves to be a major problem when trying to keep your MK1 going.

Most Mk1’s will have rotten rear arches. This is due to a combination of dirt and water collecting under the arch lip and water getting trapped in between the bodykit. Replacement arches are still available and usually the rust does not go above the plastic bodykit, so welds and joins can be hidden. Remove the plastic arch and cut back as much of the rust as possible. If the rot is bad and stretches to the inner sill and lower body you may have trouble filling this and unless skilled leave to a good bodyshop who will be able to replace properly. If the rot is not that substantial remove the rear trim cards which will give access to the rear of the arch. Check if there is rot from the inner arch to outer arch section. If there is cut it back and shape replacement plates to weld in. Once the replacement arch is welded in cover it in underseal and make sure all joins are true and closed. A good tip here is when the plastic arch is removed use a professional seam sealer/ bodyshop adhesive to reattach the arch I’ve seen other bodykits attached with self -tappers and generally they rust it looks shabby. Once it is all fitted run a small line of silicone bathroom sealant around the plastic arch to seal it. Once you have the new arch attached use Waxoyl (I used a large aerosol but you can also buy proper kits) to cover the inside of the rear arch and body panels (from access gained by removing rear trim cards). Spray everywhere you can, to help keep rot away. Another tip I used was when the arches had been fitted was to fill the inner cavities behind the arch with expanding builders foam. This helps keep out moisture and considerably cuts down on road noise.

Front wings:

Front wings tend to go but these are still available as pattern parts for around £15. Because the wings are bolt on fitting is a doddle. When the old arch is removed scrub the inner arches with a wire brush and paint everything you can with underseal. Pay particular attention to the top of the inner arch behind the strut mounting. This tends to rot badly and is an MOT failure. Whilst the wing is off it is vital that you ensure the drainage hole for wiper motor area is cleared. This hole is found at the edge of where the wiper mechanism area is which follows along the inner arch seam. I found mine to be about 10cm down from the top of the inner arch. When you clear it you may find lots of water coming out. By clearing this you can prevent the area around the door stop straps from rotting, mainly a nearside problem. Once this is done reattach the wing and seam seal all underneath the joining lips. I recommend using a professional seam sealer/ bodyshop adhesive to reattach the bodykit and not self-tappers. Again when the arch is fitted run a small line of silicone sealant around the arch.

Rear shock mountings:

Another major rot area is the rear upper shock mountings. To check all you have to do is remove the rubber cups in the boot and check around the circumference of the mounting for rust. If there is no rot you’re on a winner if there is substansial rot don’t panic, it can be fixed.The best way to sort is to take it to a good bodyshop and get a professional opinion this area is a highly stressed part of the body shell and must be in good condition. It can be re-fabricated. However, this could turn out to be expensive as the remade mounting has to be a good fit for the shock and will take a lot of work. To prevent this from happening spray tons of waxoyl underneath the mounting by removing the rear wheels and reaching up under the arch.


Floorpans tend to go in the rear footwell area and front footwell area. Floor pans are still available but are tricky to weld in. A major point to check here is where the front footwell joins the main chassis and lower suspension arm .Rot corrodes at the mounting points for the arm and as this area is double skinned to some extent welding needs to be of a very good standard as this is a highly stressed area. I have found every mk1 I have had has rotted at these mounting points. It is a good idea to check this and underseal to help prevent.


Most MK1’s tend to rust at the upper and lower tailgate lip. Filling is the only option here as replacements are not listed. To help prevent bad corrosion remove the rear tailgate trim and spray as much waxoyl as possible and use a small plastic tube to reach hard to get to areas.

Rear Valence:

Most people find that the rear valence and rear lower corners rot. Rear valences and corners are still available and welding here is easy. Neatness is not so important here as all the replaceable areas are hidden by the bodykit. It is a good idea to replace the rear corners and valence at the same time as the rear arches. The rear arches join with the lower corners, therefore, making it easier to do at the same time. Cover all the new parts with underseal and the reattach the rear lower surround with stainless fixings, preferably rivets.

Fuel Hoses:

A major part to check on your GTE is the condition of the fuel send and return hoses. After 18 years these hose tend to be pretty perished. Many will have underseal on them and thus hide the condition of the hoses. It makes good sense to replace all the hoses, hose clips and fuel filter. You will find that all the hose clips will have rusted solid and the only way to remove these is to cut them off. When replacing the hose clips try and use fuel hose clips, there is a difference between jubilee clips and fuel hose clips. Fuel hose clips make a 360 degree seal around the pipe, whereas, jubilee clips apply pressure unevenly. The rubber hoses that come from the outward end of the fuel filter and the return to tank fixing, attach to metal pipes that run the length of the floorpan. At around the front wishbone the metal pipes attach to rubber hoses again. Replace these hoses as well. Try not to mix up the pipes as one is the ‘send’ and one is the ‘return’ pipe. As the system is pressurised there will be some fuel leakage when you disconnect the hoses, therefore, use standard flammable materials precautions.


Next up is brakes. Generally MK1 brakes are poor. This is a combination of under specification for the performance of a GTE and the fact that most GTE brake callipers have seized sliders and pistons. To improve braking there are two options, Rebuild the existing callipers or replace with lager sized discs, pads and ATE callipers from a GTE 16v or MK3 Cav Sri. To rebuild the original callipers each side needs a kit. This kit contains two new sliders, seals and slider grease. They cost around £9 and a easy to fit. However a separate kit is needed for the piston seals. Personally I wouldn’t bother with this and would fit 16v brakes.

16v Brakes:
16v brakes use the later ATE calliper and have an improved slider system. By using larger discs and pads breaking is improved by more surface contact and greater heat dissipation.

Fitting and reconditioning 16v callipers:

To do this you will need, 2 ATE callipers, 2 new discs, new pads, new pad securing clips, piston reconditioning kit, brake fluid, loctite threadlock, brake cleaning fluid, copper grease and lithium grease.
Take the callipers and remove the sliders by prizing the plastic caps that cover the top the slider. Using a hex socket remove the slider. Leave the sliders in brake cleaning fluid. Next remove the bleed nipple. It is recommended to remove the piston that compressed air is applied to force it out by pressure. However, the piston may be seized. To remove the piston use a piece of brass rod or something else softer than steel. Tap the piston out by putting the rod in the back of the calliper where the hose attaches. Once the piston is out remove the inner ring seal from the piston housing and remove the outer bellow seal from the piston. Clean all traces of rust and mess from the piston housing and piston with brake cleaner. Check the piston for signs of heavy corrosion and scoring. If it looks scored and pitted you’ll have to replace the piston, which will mean a visit to a main dealer. Next use a little brake fluid to line the piston housing to aid reinsertion. Put the new sealing ring inside the piston housing.
Next, take the outer piston seal and fold the top outwards and stretch it around the bottom of the piston. Seat the lower part of the seal in the calliper and push the piston back into place. By assembling the seal in this way when the piston is pressed firmly in the seal will seat securely at the top and bottom. When inserting the piston make sure that the raised lips on the rear of the piston are lined up in a vertical position with the sides of the calliper. To aid insertion of the piston make sure that it is inserted evenly and twist the piston slightly to help slide it in. Next take the sliders and clean off all the grime with cleaning fluid. Next put grease in the slider housing, making sure that the whole housing is greased. Cover the slider with a thin layer of grease and reinsert and screw back in. Once the calliper is reassembled press the piston right back and insert the new pads. Insert the top and one side of the securing spring on the rear of the pad into the piston. The remaining part of the clip can be prised in with a suitable tool such as a screwdriver. Next replace the secuiring springs to hold the outboard pad in.

Fitting the new calliper:

First of all jack the car up and secure with axle stands. Press the pads in to push the piston back in so that the calliper can be removed from the disc. Next remove the calliper hose and collect the spilt fluid with a suitable container. Behind the calliper there are two metal ‘cups. These cover the calliper mounting bolts. Using a flat blade screwdriver prize the cups off. Next using a suitable hex socket (Allen keys will not have suitable leverage as the bolts are secured with threadlock) remove the studs and take the calliper off.
Next clean the protective layer off of the new discs with thinners. Unscrew the securing screw, you may need an impact driver if the screw is tight and remove the old disc. Put a thin layer of copper grease on the rear of the new disc (only on the areas where the disc sits on the hub!!) and attach. Given that the new disc is a larger diameter, the original dust shield needs to be modified. The easiest way to do this is to bend the lips back on the shield. It is also possible to fit a shield from a 16v. Next apply some threadlock to the calliper mounting bolds and reattach the new calliper. Reattach the brake hose, using new copper sealing washers. Fill the rear of the slider hex bolts with grease and replace the dust caps. Bleed the brakes as recommended. I recommend that you bleed the rear brakes as well as this will mean that all the fluid in the system is replaced. Personally I recommend a good quality dot 4 fluid. This is because dot 5 needs replacing more regularly because it takes in moisture more easily than dot 4, and dot 4 fluids will probably not get to boiling temp on a GTE anyway. When all this is done take it easy for 150 or so miles to bed the pads in. If you are unsure what to do with your old discs and callipers, it’s easy… Put them in the bin!

ATE callipers have a larger piston diameter so the master cylinder needs to displace more fluid to operate the brakes. This results in longer pedal travel. To overcome this to some extent, the remote servo cable can be tightened. MK1’s have the servo in the left hand drive position. To accommodate a right hand pedal a cable links the pedal to the servo. Over the years this cable may stretch resulting in more pedal travel. To tighten this cable you will need two 19mm spanners. Remove the rubber casing and slacken the lock nut and adjust accordingly. This needs to be done very carefully to avoid the brakes being over-adjusted and permanently ‘on’. If you are in any doubt get a professional to adjust it.
Back to top
View user's profile Send private message View user's gallery Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    MK1 Astra Owners Club Forum Index -> Hints & Tips All times are GMT
Page 1 of 1

Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum