Club G40 Forum
Technical => Engine and Transmission => Topic started by: LiamM45 on April 12, 2009, 07:33:21 pm
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Today was a bad day.
I was happily tootling along the A1M on my way to Elsecar and a Mk5 R32 Golf came flying up behind me. So we had a bit of a play and I made him look a tad silly. Good times...
So I slow down and start hearing a slight rattly noise, like a loose bit of trim or a loose bracket...
I approach the bit where the A1M and M1 seperate and hear a 'pshhhhhht'... hmm. Car shuts down and I throw it onto the hard shouler, almost getting wiped out by my compatriots mk3 Polo at the same time!
Pop the bonnet... ah. I am now minus one supercharger belt. So, having a spare belt in the car I called the RAC to help fit it...
RAC starts taking my car apart and the belt is stuck fast. He takes the timing belt cover off and umm... one snapped timing belt. Oh cock.
What I am curious to know is, I've heard VW produced 'non-contact' engines, which didn't kill the valves and valvetrain when the timing belt snaps, is the PY engine one of those engines?
Lastly, worst comes to worst, what sort of wallet damage am I looking at to replace the valves, etc?
Thanks... Liam
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You're not going to know till the head comes off, but "etc" could be pistons and head damage. PY is a "contact" engine so good luck, but not every days a fishing day!
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We were thinking, firstly, to just chuck another timing belt on and see what happens. Not sure if this is the best idea though...?
I imagine a new head will not be easy to come across.
Already thinking of more modern, yet still supercharged, running gear... worst come to worst! :P
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Damn Liam, that is a shit day >:(
The good news is the cylinder head isn't specific to the G40. Any 1.3i hydraulic head will do the job. What is specific to the G40 head is the exhaust valves which are sodium filled. A set of G40 exhaust valves can be fitted to a "normal" head. However, I wouldn't think they'd be cheap as they're VW dealer only jobbies.
GWerks or a similar specialist may be able to help getting an equivilent or go the whole hog and get a big valve conversion done.
Until the head is removed, you won't know the full extent of the damage. However, I doubt it'll be cheap. :'(
Good luck mate,
Richard.
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Liam the chances of you not smashing the valves are very very slim, get the head off and inspect the damage.
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yeah I wouldn't just chuck a belt on and see if it works. You could end up causing even more damage if valves are already bent and to be honest you'll be bloody lucky to not have bent any! Out of interest, when was the belt last changed?
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Roughly 15-20k ago :-[
Guess when funds allow I'll take it over to my mates unit and strip it down, again.
Since I work off the theory of build it bigger/harder/faster when it breaks, have you got any more info on these big valve conversions?
I'm tempted to just start fresh with the engine and rebuild the whole lot.
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just sounds like a bit of bad luck then :(
Get the head off before you get carried away, if it just needs a couple of valves it shouldn't cost much.
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I'm putting it down to bad luck and some over enthusiastic driving.
If the damage is minimal then I suppose just replacing the valves would be sensible, but I think the time is right to loan money to buy a nice daily and restore the G40. It needs paint as well as this now, so it might be worth taking it off the road for a while and do it properly, rather than rush it.
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could be a seized water pump = -check that as well!
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http://www.polog40.co.uk/forum/index.php/topic,1770.0.html
G40 head for sale.
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Some slight progress here...
Car is going over to my mates unit at the weekend, he's gonna chuck a cambelt on and time it up, try and turn it over by hand and see what the crack is.
In the meantime I priced up some parts. :-\
8 new valves - 125 pounds. Not too bad I suppose.
Now this is where it gets worse. The guy doing it (a very highly spoken of VW specialist) seems pretty much convinced the pistons will be damaged, personally, I'm not convinced. Obviously if they are chipped then they will need replacing, can't argue that, but he says if they are scratched on the top they'll need replacing? Now oily bits are not my forte, especially the insides of an engine, I'm very tempted to get a second opinion if this is the case. Would it be worth getting pics of any so-called damage for the second opinion of people on here? I'm just doing all I can to not get ripped off :-[
I priced up 4 pistons, which comes to 400 quid (well 96 each). I just think it's pointless getting stock pistons though, I might as well step up to forged internals if I'm changing them, obviously with a view to more power in the future.
Can anyone offer any opinions/advice upon the situation?
I'm finding it very hard to justify another 1k+ in repairs on this car. I've had the car since July 2008 and it's ran for 4-6 weeks in total. :-[
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could jsut buy another g40 bottom end?
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I was thinking just buy a whole new engine and start again! Just means yet another Summer off the road. If I buy a new engine to build up I might as well get a subframe conversion and LSD while it's all out. After reading Yoof's advice I think it's time to concentrate on making the car handle better and put the power down better, and given a whole Summer and Winter I'll have saved up plenty of cash.
I'll know for sure what will be happening over the next week. Surely my luck is about to turn with this car! For all I know it could be a couple of bent valves. *touches a very large bit of wood*
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if you do just change the valves then make sure you lap them in.
if the pistons are dead then this is a good time to go to 1341cc.
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Quite frankly! I`d be amazed if a VW specialist said to put a timing belt on
and Time it up to see what happens. I wouldn`t have him anywhere near
my car and i shudda to think he`d do that to anyone`s.
Valves are Cast iron and usually fracture when bent and more to the point,
if you turn it over and a valve can`t seat properly because its Bent then it
may Snap the head off it and try to compress it between the head and the
Piston wich will either lock the engine solid or Hole the Piston under load.
I Strongly suggest that The Head is removed to asses the Damage first.
You may well find that some Inlets are bent too.
It has been known to straighten valves but only ever so slightly bent ones.
If you take an old Valve and grip the stem in a vice and strike the edge of
the Head with an Hammer then the Head will Break off.
It`s amazing how easy it is too. Even easier with a bent Valve.
So don`t do the belt bit, Get the Head off and check the Damage before
anything else.
Also check the Valve Guide`s where valves are bent for ovalness.
Take pics and post them for further assistance.
There are people on here who Really know their stuff and more to the
point, the G40 Engines.
Good luck.
It`s unusual for a timing belt to brake at 15-20k so see if owt`s been
chaffing at it.
It`s also possible that it was fit too tight wich lessens their life as well.
Genuine Vag Timing Belts are £9 including the Dreaded so fit Vag.
They also fit the Pulley`s properly in their profile, unlike a recent GSF purchase.
Fred.
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Fred is dead right.
Get the head off.
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Thanks for the advice, it really is appreciated. I shall have a word first thing Monday morning with the guys who have the car. Like I've said previously the insides of engines are not my strong point and I do need a bit of guidance :)
I'm at the point now where I feel I should take the car off the road and get the little niggles sorted out properly and rebuild this engine with a bit more grunt and with reliability in mind. No wonder people think I'm mental... I just can't let a G40 die! There's a list as long as my arm of stuff I want to do to the car, so now it's time to do it.
I dubbed the car "MoneyPit", how true! Haha.
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Well, had a call today, head came off - they never tried just putting a timing belt on, as they agreed it was too risky.
Not that it mattered.
8 bent valves
4 smashed pistons.
1 fucked cylinder head
Possibly more damage to the bottom end too.
Going to inspect it myself tomorrow and discuss plans. It will be rebuilt but not with the PY engine in.
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ouch - looks like a block/head is needed - not sure what i'd do - suppose it depends on cash...
1341 bottom end + bvh - if you can afford it
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sorry to hear that!
as pete said go for 1341cc mate!
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Not sure if I want to dump that much money into a G40 engine.
Initial plans are to go a different lump with more BHP standard. It won't be keeping it original but my car is a GT conversion, so no loss really!
I'll post some pics as things get done if it's of any interest to people here :)
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Yeah! Post pics Liam.
It`s always good because of reply`s/post`s and the fact that People
with G40 knowlege will reply wich in turn will help You gain Knowlege
of Your engine.
Gives us more reading fodder, and keeps the site Alive.
Fred.
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ouch, sorry to hear this! Sounds like it couldn't be much worse.
I guess one big question is the condition of the block itself. If it's rescueable with just a rehone then you might be able to find a spare set of pistons from someone one here who has converted to 1341cc. Then you;ll need to get hold of a head.
The other option is to just get hold of a g40 bare engine off someone.
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Well, after a long, and pretty hard, think, I've decided to cut my losses and break the car to try and re-coup some money towards a new Polo based project (mk4 'loon I'm afraid). After all, it's not a 'proper' G40, so I'm not breaking anything rare or valuable.
I can't justify putting any more money into the car and I might as well split it for parts so other Polo owners can use the good bits.
If anyone would like anything off the car just drop me a PM and we can sort something out. :)
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There's a complete G40 engine conversion on CP for £600... Sell the loom, ECU, 'box and charger and the head/block won't owe you much.
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The thing is Andy, my shell has been in two accidents now, and to build the car up how I want I would end up spending a LOT of money. It needs too much money spending on it, which I just can't justify any more.
I've had my fun, now hopefully people can salvage bits from my car to keep having fun with their G40s, etc. :)
I'd rather put the money into building something different, but keeping the sleeper theme. I'm breaking the G40 to fund a Mk4 Polo saloon base car and the fitting of a full roll cage, hopefully ending up with a Mk4 Polo saloon 20vT by this time next year. I know that's gonna be a bit frowned upon, but hey ho, I fancy something a bit different! :)
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Polo 6K saloon 20vT is the daily I wanted to build for myself, so will be very jealous!
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Nightmare. Can see why you've come to that decision but still a real shame.
Hope you get your new toy up and running soon as.
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I'm breaking the G40 to fund a Mk4 Polo saloon base car and the fitting of a full roll cage, hopefully ending up with a Mk4 Polo saloon 20vT by this time next year. I know that's gonna be a bit frowned upon, but hey ho, I fancy something a bit different
no I certainly wouldn't frown on that! It'd be a great project, if you do it make sure you put lots of pics on here. 8)
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yep am not polo/vw blinkerd!
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If you want a low mileage diesel shell mine runs out of MOT in Sept, I'll not be replacing it as I've found something else. PM me if you want more details, only want a few hundred quid.