Astra mk3 Arctic 1.6 8v to 3.0 24v build

[Harvey]

Enjoyed driving the Astra V6 this year and last month it went for its annual health check and I’m pleased to say no split ball joint boots this year and it passed. MOTer did comment on the loud exhaust but was aware I’ve done all I can to quieten it down with the extra silencer. It’s now SORN and will be making a welcome return to the road next year.

[Harvey]

I noticed the exhaust tips had started to crack and peel 3yrs after having them ceramic coated.


Due to the above issue I decided to try another company Maldon Shotblasting & Powder Coating and had them recoated in Graphite Black.



Prior to fitting I painted the shiny stainless steel rear visible face in black VHT.


Then jacked up for easier access and yes I used axle stands, safety first!


All done, sealed and bolted in place.

[Harvey]

I decided it was about time the Astra V6 had an oil change as it was last done in August 2018, oh heck. It’s only covered around 1,300miles since then but I still felt I had neglected the poor thing. Out it was dug from the Winter slumber and last month it got some loving and check over for its 2023 usage.



Brought the engine up to temp and removed the sump bung and left it dripping to get every last drop of oil out.



The early Vauxhall V6 lumps are a bit of a pain as the oil filter is located on the front of the block and if you don’t shove a rag into the gap just below between block and sump the oil can go everywhere and you end up chasing random drips between the lowest point of the bellhousing and block. They later used paper cartridge filters but these cost more than the metal screw-on version so I stuck with the early filter setup obviously, lol.



Nothing but the finest old school genuine stock from my shed stash, this only leaves me one more OE oil filter on my shelf from way back and my bulk purchase pre PSA takeover

[Harvey]

On Saturday the wife and I popped along to the new VauxALL show held at The British Motor Museum displaying on the Vauxhall Drivers Club stand. A fab show with a relaxed atmosphere and some lovely cars.

[Harvey]

When I had the Astra V6 out and about last month I had a couple of occurrences of the dreaded click click before the starter engaged and the engine fired up. I’ve never had this previously but it’s a sure sign the starter wasn’t happy. My intention was to get the original Bosch refurbished but found a reman with 5 year warranty cheap as chips so bough it. Next mission was to replace the starter which isn’t easy on the V6 lump with tech docs saying remove this that and the other before even reaching the starter. I fortunately only had to remove the drive shaft and intermediate shaft.





I made a bung to hold the gearbox oil back using a socket/bag/tape and didn’t lose a drop.



After a wrestle, some mumbling followed by swearing the old (dodgy) starter was off.



Old meet swanky new starter.



On it goes and assembly is reversal of disassembly. Issue resolved and the starter is working flawlessly as expected.



I also noted a split in the intake hose from the airbox to the MAF (Mass Air Flow sensor).



While removing this damage I also found a split in the hose from the MAF to TB (Throttle Body) but I had a good used undamaged spare on my shelf so this was an easy fit.



Back to the pre MAF hose I investigated a few options but a generic silicone hose was simply too tight due to thick hose walls to fit with a clip to the airbox.



I wasn’t able to source a new OE replacement anywhere so I simply used 50mm wide insulation tape and wrapped the damaged hose. As you can see it looks great and is fully sealed, you wouldn't know if I hadn't told you. Yes, I’m aware Roose sell a silicone kit with both hoses here but I really wanted to retain the original so my solution made sense to me.

[Harvey]

After 10 years of faithful service one of the aftermarket bonnet struts on the Astra mk3 V6 decided to fail so I had to temporarily revert back to the OE stay until a plan was hatched.



The failed strut had no details meaning I had no idea what force it was but it did measure 435mm expanded length. After researching gas spring struts online and some strategic measuring and weighing I figured out the failed strut was asserting 300Nm (using the remaining good one) pushed into scales reached 30KG of force, the single strut was enough to hold open the bonnet fully so slightly overkill pressure. I did weigh the bonnet lifting force at 10KG and roughly x3 due to the strut fixing location meant 30KG (10Nm per 1KG so 300NM) rounded up. The closest generic struts come in forces of 100Nm/200Nm/300Nm up to 1000Nm each and I chose 450mm length so purchased a pair of 300Nm meaning I was replacing like for like ish from this eBay seller. Enough waffle and I won’t bore you with all the scientific calculations which are a thing and required when figuring out what spec struts you need, Google it and you’ll see what I’m on about.

My order arrived and you can clearly see the dead strut asserting no force at all, floppy and lifeless.



I mocked up a new strut and they had the exact same metal 10mm ball socket and pin fittings which fitted the cars existing 10mm ball pins, winning. They were a lovely all black finish and the 15mm extra length held the bonnet open a tiny bit more but within tolerances so all good.



I carefully installed both struts and can gleefully report they work great and have a nice damping action near the end of the opening stroke (like OE boot struts) unlike the previous which just slung the bonnet open. I can not remove the OE bonnet stay again as the struts are working great.

[Harvey]

Popped up to The Motorist a few Sundays ago with the Astra mk3 V6 having heard it was a decent place, we weren’t disappointed and what a great venue. If you have never been it’s well worth a visit. Pics can do the talking so here goes.


I was a couple of miles from home on the return leg from The Motorist and heard the dreaded fuel pump grumble, oh heck. Luckily I made it home and after the usual checks a dying fuel pump was diagnosed. Couple of clicks later and an ITP318 was ordered. This is a Hi branded direct OE replacement which is a sub-brand of Sytec.

The Astra mk3 has a very useful top access so removing the pump assembly is easy.



All clean inside the tank so no concerns with that and I also checked the external inline fuel filter plus the return line and they were good.

The fuel pump assembly was stripped to swap the dying with new pump.



Refitted the assembly and popped sealer either side of the gasket and on the bolt threads so no nasty smells could escape. Tested and all working with no nasty pump noises and fuel getting to where it’s required.

Also on the way back home the RH indicator started flashing fast having worked fine all the way to the meet. It was the front headlight indicator as the crimped and soldered +ve had broke on the adaptor loom with the bulb fine. Rectified with a new length of wire, twisted at the end and soldered.

[Harvey]

Since building the Astra mk3 V6 I’ve had x2 physical Astra keys but only x1 transponder chip able to start the engine of the donor Vectra ECU & immobiliser so a plan was formulated. After cross referencing my working coded chip being a Philips PCF79735S I bought a virgin new never programmed NXP PCF7935AA being an ID40 T12 as you can't reuse previous programmed chips. This NXP chip can be used for any ID40-45 from the research I’ve done and I found this useful transponder model chart for others who might be wanting to do similar.



Next job was to dig out my trusty Opcom and find the paperwork with the donor Vectra security code. Using the spare key with new unprogrammed chip turn ignition on and watched the EML flash as it wasn't paired with the immobiliser, this being default behaviour as it won't allow you to start the engine. Then in Opcom>1998 (W)>Vectra-B>Body>Immobiliser>Programming and enter the security code where you see this screen.



Click on 'Programming Transponder-Key' and from the dropdown select a known spare slot, in my case no.3.



Job done. You will however still note the EML light is flashing so back out of the Opcom screens to the top level, turn ignition off and then on. At this point your see the EML is steady and not blinking so the chip is now working and programmed.



I popped the new programmed chip into the spare key holder having had to hack the old chip out from the previous engine as it was glued in.



I confirmed the transponder chip was fully working by going back into the measuring blocks for the immobiliser where you can see ‘Transponder-Key 3 Status = Programmed’ plus ‘Immobiliser Signal = Transmitted’. So now I have x2 fully working keys able to start the engine, success.

[Harvey]

I gave the Astra a breath of fresh air and replaced the pollen filter using the very last of my genuine GM stock. They're an easy fitment as you simply pull out the water guard and pop the two clips, no tools required.



With the MOT looming I noticed the rear number plate light wasn’t working so popped the fitting out and gave the contacts a clean which kicked it back into life.



Last Friday it was MOT time and I’m pleased to say another pass…although it did get another advisory for the loud exhaust, yes it’s loud thanks to the V6 grumble



While it was on the ramps I grabbed underside pics as it’s rare you get the chance, all looking great under there.

[Harvey]

The wife and I have discussed selling the mk3 last year but we both aren’t quite ready just yet so it got dug from its Winter downtime with the dehumidifier checked and found to be rather full after 6 months!


I then noticed the sagging headliner which had got much worse so I’ll be removing that later this year and outsourcing a fix.




Another job I had planned for the car was to check the front LH caliper as it had become ‘sticky’ as I noted it was getting hot during our last few drives. Nothing obvious found and as I had a new seal kit it made sense to fit it, brakes were then bled and good to go for this year.


I’m rather tight for space and had to revert to drastic measures to get the mk3 and my new toy behind closed gates, sketchy as but it worked great.

[Harvey]

The Astra mk3 hasn’t been out to play this year but will be making a reappearance next year, got the roof lining still to sort and it’ll be good to go. It hadn’t been started for a while but does sit on a battery conditioner so I fired it up the other week and all was good with no dramas.


My funky monkey hybrid mk2/mk3 dash is still rocking it and working great.

Outside temp sensor is sorted as I had grief finding one in my spares stock that played nicely.

On a day with temps above 20C why wouldn’t you check the AC is still ice cold, nothing to see here with just the clunk of the compressor clutch as you press the on button.

[Harvey]

We’ve not used the Astra mk3 V6 this year but it was MOT time this month so I went the long way and thoroughly enjoyed the drive there.



It was then a nail-biting time, will it or won’t it pass.



I need not fear as it’s got another year’s clean health stamp with a whopping 70 miles between checks this time and the usual ‘noisy exhaust’ advisory, I know I can hear the darn thing when I’m driving!

[Harvey]

It was action stations last month with the Astra as I decided to take the roof lining out due to the fabric sagging after finding a local vehicle upholstery company to fix it properly as the car deserves it. It’s booked in next month to get sorted so I’ll update when completed, in the meantime I made the car drivable minus the roof lining.




After 18 months of storage the boot lock had got sticky so removed it and cleaned it up.


Took the cheap dehumidifier out the car, you can see it’s been working hard over Winter.

The reason for this manic activity is the car went back on the road last weekend with the first stop, spending more money on Shell V-Pooper.

Had a fab blast to blow the cobwebs off listening to the V6 grumbles with a planned trip to StayKool in Derby as the aircon was last serviced in July 2021, eek!

I took my tools as the ac service connections are behind the rad in front of the engine so less than one min later the front intake was off giving easier access.

There was nothing to fear as it still had 750g in the system, darn amazing and proves how well sealed it was.

The full package was chosen to future proof the ac with Cool-Shot and Extreme Leak Sealer which are in there for life before the system was filled with 900g of R134a. Car was then started and interior vent temp checked brrr it’s cool inside.

[Harvey]

The Astra V6 had an epic service as I realised my normal standards had slipped realising, I’d not changed the timing belt in 12 years/4.5K as it should be 4 years/40K. I got cracking and stripped it all down which is a mission, found TDC and popped the locking kit on. I needn’t worry as the old belt was perfectly fine but piece of mind and fiddle time is best.

I popped the new belt on and went through the tensioning procedure and all went well and it’s alive with no piston/valve contact. I won’t lie as I’ve done a few V6 timing belts so should know what I’ve doing. I obviously used a decent brand Gates belt as you can have all sorts of issues with lesser brands on these lumps.


Next job was to drop the engine oil which had covered a little over 500 miles but as expected still dark due to heat soak.


I dug out what is surely now a rare sight and should be in a museum…genuine Vauxhall/GM oil and oil filter with 5.0L of the finest retro oil and filter added to the V6.

With a very capable assistant, the wife, brake fluid was changed while in hover mode...out with the old and in with the new.

[Ricky352]

Good work, must be very satisfying to have all that done. I was reading an old Total Vaux magazine from 2011 (I think) yesterday and they were saying how Vauxhall missed a trick by not doing a V6 Astra to compete with the likes of the VR6 Golf etc.