Vauxhall Omega 2.5 V6 Engine rebuild

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Tue 28 Jun 2005 23:11
Vauxhall Omega 2.5 V6 Engine rebuild - Omega mad
GREAT SITE!! Can anyone help me with this.....?

I am just starting on my first engine rebuild project after purchasing a second hand 2.5 V6 Vauxhall Omega engine.

There are a few marks on the cylinder bores, for which I have been quoted £20.00 plus VAT per cylinder for boreing and honing.

I was impressed with this price but nearly fainted when I was quoted £110.00 plus VAT for each piston!!

Can anyone give me advice/ help on a) keeping costs to a minimum and b) alternative options....

Cheers....

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Wed 29 Jun 2005 00:12
Vauxhall Omega 2.5 V6 Engine rebuild - Aprilia
As the Irishman said, "I wouldn't start from here".

Picking a GM V6 as a first rebuild was probably a bit rash. There are some specialist GM parts suppliers who will do you parts a bit cheaper than the dealer, but even so you are going to be spending a great deal of money if you do it 'properly'.

Is the car really worth it? Omegas usually aren't worth much - would it be cheaper to get a s/hand engine?
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Wed 29 Jun 2005 20:33
Vauxhall Omega 2.5 V6 Engine rebuild - Omega mad
Hi Aprilia, Thanks for the advice! I didn't think the pistons would be that price for a start! I was ready for the challenge and hard work but not to declare myself bankrupt....

I have some experience in the mechanical field but have never stripped & re-built an engine completely. I came accross the engine for £100 and owning a mint 1999 Omega I would have liked to have re-built the engine with the intention of finally being able to show off a mint gleaming and painted lump under the bonnet, also gaining the experience, enjoyment etc along the way. I didn't expect to find 1 or 2 of the bores scored though, a few valves bent in the head I wouldn't have minded.

This may be a daft question but if I had the block bored etc, could I not fit used pistons? Or is it a case of scrap the block.

Appreciate your response and any advice you may have......

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Wed 29 Jun 2005 20:48
Vauxhall Omega 2.5 V6 Engine rebuild - Aprilia
If you bore the block then you'll need oversize pistons - not easy to find secondhand.
Depends how much time you have on your hands, but as far as I am concerned life's too short for this kind of thing.

Much better to scrat around for a good engine in a written-off car.
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Wed 29 Jun 2005 20:48
Vauxhall Omega 2.5 V6 Engine rebuild - Aprilia
PS- watch out for the oil cooler problem too!
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Wed 29 Jun 2005 21:34
Vauxhall Omega 2.5 V6 Engine rebuild - Omega mad
Thanks alot for the advice, i'll let you know how I get on!!!!
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Wed 29 Jun 2005 23:27
Vauxhall Omega 2.5 V6 Engine rebuild - Dave N
Now you know why the 'quality' rebuilt engines advertised at super low prices are simply junk. About al lthey do is give them a coat of paint and hope for the best.
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Thu 30 Jun 2005 16:11
Vauxhall Omega 2.5 V6 Engine rebuild - stokie
This firm are cheaper than Vauxhall dealers:
www.autovaux.co.uk/
It's a good idea to find out the Vauxhall part number before you aproach Autovaux, as my dad had a bit of a nightmare receiving the wrong back road springs for his 2.5 omega, Autovaux finally sent the right ones when he quoted the part number from the old broken spring.

Sounds like the engine that's in your car now runs OK, why not take that out and spray it up, or dismantle it and blueprint it.
Couple of my pals did that on Fords, I never did but my claim to fame is fitting central heating to my first house...

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Thu 30 Jun 2005 21:20
Vauxhall Omega 2.5 V6 Engine rebuild - Omega mad
HAHA.

NICE ONE!!! That is one thing I would not touch, but well done!!

Thanks for the advice, I'll keep on searching for a project to do, Good idea about the engine, It is a mint omega, and i've always wanted to do an engine to show off!!

Back to the thinking stage now though...........
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Thu 30 Jun 2005 21:22
Vauxhall Omega 2.5 V6 Engine rebuild - Omega mad
I didn't realise to do it yourself would be so expensive, I was looking forward to the challenge!!!
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