Club G40 Forum

Technical => Engine and Transmission => Topic started by: james22sniper on May 06, 2012, 09:12:27 pm

Title: Broken gear box
Post by: james22sniper on May 06, 2012, 09:12:27 pm
Had a catastrophic internal bearing failure resulting in a metal fragment punching thru the case. Be interested to hear if anyone has had a similar experience and has had the hole welded up. Thanks!
Title: Re: Broken gear box
Post by: james22sniper on May 06, 2012, 09:31:17 pm
Photo hopefully
Title: Re: Broken gear box
Post by: james22sniper on May 06, 2012, 09:32:29 pm
And another
Title: Re: Broken gear box
Post by: hayesey on May 07, 2012, 01:03:52 pm
just swap the casing it's only the clutch housing side it's just ten or so bolts to remove it.  Presumably you're taking it apart to replace the bearing and clean everything anyway?
Title: Re: Broken gear box
Post by: Nick_S on May 07, 2012, 01:11:53 pm
I have spare gearbox casings if you need one  ;D As Hayesy says, if you do this you'll need to replace at least all the bearings on that side of the gearbox. Ideal time to get the whole box overhauled anyway if you can afford it!
Title: Re: Broken gear box
Post by: james22sniper on May 07, 2012, 02:08:16 pm
Hi.. How much for your outer casing and location? Thanks!
Title: Re: Broken gear box
Post by: Nick_S on May 07, 2012, 02:22:55 pm
Hi.. How much for your outer casing and location? Thanks!

PM'd
Title: Re: Broken gear box
Post by: Oli b on May 07, 2012, 05:46:13 pm
Similar hole happend to me but somthing went in rather than came out
(http://i833.photobucket.com/albums/zz257/oli-b/03f27d21.jpg)
Title: Re: Broken gear box
Post by: james22sniper on May 07, 2012, 05:58:21 pm
Did you get it fixed?
Title: Re: Broken gear box
Post by: Etches on May 07, 2012, 07:02:21 pm
I had a more serious hole when i bought a g40 box which the driveshaft had popped out and smashed the bell housing , as above just change the housing
Title: Re: Broken gear box
Post by: james22sniper on May 08, 2012, 05:52:07 pm
 :-[Took the box to a local gear box specialist who wrote it off so now looking for a whole box!
Title: Re: Broken gear box
Post by: Oli b on May 08, 2012, 07:37:02 pm
Yeah had the hole welded up as i have acsess to a alloy welder just gotta re fit it when i get the time Other than let all the gearbox oil on to the clutch it diddnt do any further damage luckly
Title: Re: Broken gear box
Post by: Etches on May 08, 2012, 08:36:57 pm
Saying that i had to change the diff as there were chunks out of it but that was it, pure luck though!
Title: Re: Broken gear box
Post by: hayesey on May 09, 2012, 09:32:56 am
:-[Took the box to a local gear box specialist who wrote it off so now looking for a whole box!

did they say why?  Do they realise that proper G40 boxes are like hens teeth to find?  

Really, unless it's absolutely shat itself and teeth on gears are all knackered then it's probably going to be more worthwhile rebuilding it and having a nice fresh G40 box than waiting weeks/months/more?! to find another ATV for £200 which is unlikely to have been rebuilt.  If they have thought "oh it's only a polo gearbox, there's loads of these about for £10 each", then they might just think a basic rebuild isn't worth it.
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 10:04:18 am
Turns out it was not a G40 box but just a standard 1.3 Polo... apparently. Many teeth stripped and bearings knackered! The guy said not worthwhile. But then how would you repair a gearbox if not by stripping it down and replacing broken gears and bearings??? But also... if as it turns out it is nothing special, he is probably right.
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 10:12:46 am
Photo showing 8P and 085 box markings. So am I correct in thinking this is a basic Polo box and NOT a G40?
Title: Re: Broken gear box
Post by: hayesey on May 09, 2012, 10:13:05 am
fair enough, I'd have to agree with them then.  If you need to start buying new gears then it's VERY expensive.  Looks like your final drive set is knackered too.  

Having seen that I'd say finding a 2nd hand complete box is the best answer too.

What code is on the casing?  
Title: Re: Broken gear box
Post by: hayesey on May 09, 2012, 10:16:18 am
ah just seen your new pics.  Yes 8P is just a normal 1.3 litre 5-speed polo gearbox.  Not worth much at all.  You can find these for sale for not a lot.  They are the usual box to put on a g40 if the original ATV coded box is shat itself and you can't find a proper replacement.  The ratios are similar but not quite the same, about as close as you'll get.  Top end is a bit compromised and I'm not sure it'll do 60 in 2nd with an 8P (which it will do with an ATV). 

Also, you can't fit an LSD to an 8P as they don't have bolt-on crownwheels on the diff.

But you've been using an 8P anyway so using another one shouldn't be a problem, it'll just be the same.
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 10:19:44 am
Thanks for all your advice and help!!! I'm learning all the time! Its actually my sons car so he will be relieved that we should at least be able to get it back on the road! But I think I might advise him... no more trips to SANTA POD!!!  :)
Title: Re: Broken gear box
Post by: djtez on May 09, 2012, 10:35:48 am
now now , cant be harsh on the boy..

thats what these cars are for .. fun ;D

Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 01:30:46 pm
hayesey... what can you tell me about an AHD box? I have been told this is a direct replacement for the original having given the reg no. to a reconditioning company. Thanks.
Title: Re: Broken gear box
Post by: hayesey on May 09, 2012, 01:36:04 pm
I think that's a GT gearbox, not the same at all. Much shorter ratios.  An 8P would be better.  I see someone has replied to your wanted thread with a proper G40 box for £200, I'd buy that if I were you.
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 01:42:24 pm
So the G40 box and the 8P have the same fitting dimensions and should go straight on?
Title: Re: Broken gear box
Post by: djtez on May 09, 2012, 02:01:46 pm
yes
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 02:06:08 pm
I feel a trip to the north coming on then!  :)
Title: Re: Broken gear box
Post by: hayesey on May 09, 2012, 02:38:30 pm
they are the same externally, just different gear ratios.
Title: Re: Broken gear box
Post by: Nick_S on May 09, 2012, 07:40:58 pm
Ouch, looks like the end bearing on that relay shaft has fell to bits (nothing left there now) causing damage to the final drive set and gear set next to it!

Deffo not worth repairing.
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 07:59:22 pm
 :(That about sums it up! Things were looking up earlier when I had a good response to my wanted add but the guy disappointingly put his price up when I expressed an interest. Maybe it would be worth it but to quote one price and then stick another fifty quid on top is not very friendly! Disappointing!
Title: Re: Broken gear box
Post by: Nick_S on May 09, 2012, 08:06:07 pm
Just buy a second hand 8P or CEG gearbox. It really isn't worth paying the premium for a G40 box unless your planning on fitting an LSD?
Title: Re: Broken gear box
Post by: james22sniper on May 09, 2012, 08:24:23 pm
 :)Thanks.. My search will go on!
Title: Re: Broken gear box
Post by: hayesey on May 10, 2012, 09:26:48 am
surely Rich isn't being serious when he says it's £250? 

I would pay the £200 for a proper ATV box. 
Title: Re: Broken gear box
Post by: james22sniper on May 10, 2012, 09:32:04 am
I did get a reply from Rich and he says he was joking and the £200 stands! So relief! Hoping to get up there this weekend. Thanks for your advice! Is there anything i should look for specifically when i collect it? Would it be reasonable to ask for it to be opened up?
Title: Re: Broken gear box
Post by: hayesey on May 10, 2012, 10:39:55 am
I'd not open it up, you'll need to reseal the halves together. 

I would put it into each gear and make sure it changes gear OK.  Then turn the input shaft and make sure it turns smoothly and there are no untoward noises.  Perhaps do this in every gear.

First thing I'd do when I've got it home is put some fresh gear oil in it.
Title: Re: Broken gear box
Post by: james22sniper on May 11, 2012, 05:28:13 pm
Don't suppose anyone has a number for richg40?
Title: Re: Broken gear box
Post by: james22sniper on May 13, 2012, 09:35:45 am
 :)A happy ending! Thanks Richg40.. Fitted your old box with a new clutch and its back on the road!!! :) So have a few spare gear box components now if anyone needs any?
Title: Re: Broken gear box
Post by: djtez on May 13, 2012, 10:02:13 am
Well done james , glad to see another happy ending.!

Title: Re: Broken gear box
Post by: Richg40 on May 13, 2012, 08:02:59 pm
Glad to see it's been put to good use.
Title: Re: Broken gear box
Post by: james22sniper on May 14, 2012, 09:06:48 am
Will says it has transformed the car! Much better gear ratios compared with the 8P box! Smoother all round! We changed the gear oil and even the old oil was considerably better than that which came out of the original box. Not suprising though as having totally stripped out the old box, I found that a couple of the small fine thin gear rings had actually melted and fused themselves together hence the smoke when it popped I guess! Most of the rest of the internals were ok tho and the case is fine and I will get the outer case repaired as a spare for someone in the future!
Title: Re: Broken gear box
Post by: hayesey on May 14, 2012, 09:18:07 am
glad to hear it!  Yes the proper ATV is better, it's worth the swap!

I wonder if the old box failure was down to lack of oil or gone off oil then?  If it got that hot it must have been dry surely?  Not that it really matters now.
Title: Re: Broken gear box
Post by: james22sniper on May 14, 2012, 09:25:38 am
Could be??? Will never know how much oil there was inside as the hole created by the bearings making a break for freedom would have let the oil drain out before we had a chance to disassemble it. But a lesson to others... good to check the state of theirs!
Title: Re: Broken gear box
Post by: hayesey on May 14, 2012, 09:42:45 am
yeah that's true!

Definitely worth everyone checking gear oil levels and age.  I reckon the biggest cause of failure of these boxes is down to low oil or degraded old oil.