when to change gearbox

Post by **dalebrignall** » Fri Nov 16, 2007 6:46 pm

my gearbox is working fine.the gear stick gets rattly when the oil warms up in the gearbox.i took my brother from aus for a spin today and he thaught the gearbox sounded a bit rumbally.he thaught the leyshaft barings might be on there way out.the engine is not rumbling because it has only done 3000 miles and i am getting 60 psi on a run 40 on tick over.it is not jumping out of gear yet,should i be concerned or wait till it starts jumping out of 2nd.thanks dale.

Post by **MoggyTech** » Fri Nov 16, 2007 7:08 pm

The gearboxes are notorious for being farely noisy. 4th should be fairly quiet as it's direct drive. People used to new cars, don't realise how the older stuff sounds.

Easy to diasgnose where the noise is from.

Noisy in neutral, noise stops when clutch depressed, Main gearbox bearings and or layshaft bearings/worn layshaft case hardening.

Noisy in 1st only (Whine) normal
Noisy in 2nd 3rd thrust washers worn on mainshaft

If it is a rumble as opposed to a whine, suspect main bearings in the box, however, the box can last for ages in this condition.

Stick rattle is likely to be the little 'o' ring under the stick ball, or weak anti rattle spring. 10 minute fix

Keep oil topped up, and use engine oil only in the box NEVER Hypoid, it eats phosphor bronze bearings.

Post by **bmcecosse** » Fri Nov 16, 2007 7:30 pm

Start looking for a good spare - but as you suggest - wait till it starts jumping out of second before fitting the spare. It may go on for years!

Post by **downsey** » Tue Nov 20, 2007 11:51 pm

I drove my car for over a year with a bad second gear haha. I had to stay on the throttle and keep it jammed in gear with my hand

Post by **nslocomotive2** » Sat Jan 03, 2009 7:24 pm

Hi people,

Noisy in 2nd 3rd thrust washers worn on mainshaft

I have a question what's involved in replacing the thrust washers on the main shaft, I have just picked up a second minor that is running and the 2nd and 3rd gear literally scream at you. Its not something I cant live with but If its a straight forward fix then I dont mind tackling it at some point, however I could swap it with my other ones, engine and box but that feels wrong

Post by **les** » Sat Jan 03, 2009 7:32 pm

The thrust washers are ok to replace, you will need to dismantle the gearbox to do them though.

Post by **bmcecosse** » Sat Jan 03, 2009 9:14 pm

If it's screaming - it's going to need a lot more than a couple of thrust washers! Look for another gearbox. Of course - well worth checking if there is any oil in the box !!

Post by **nslocomotive2** » Sat Jan 03, 2009 11:58 pm

well I'm rolling underneath it tomorrow to have a look at it, and i will be doing an oil change to see if it helps, we will see if its oiled up then, I will probably try and get a replacement ready to drop in. I may even rob the engine and gearbox out of my other saloon as a temporary fix if it all goes bang.

the advice is usefull, many thanks.

Post by **nslocomotive2** » Sun Jan 04, 2009 3:21 pm

bmcecosse wrote:If it's screaming - it's going to need a lot more than a couple of thrust washers! Look for another gearbox. Of course - well worth checking if there is any oil in the box !!

NO OIL IN THE BOX

I got the car recently from a family member and i find it hard to believe he never checked it but it is possible.

Thanks for the advice, i've only done five miles in it since i've had but it may have done more, without oil ????

I will check it again after a week or so and see if its still the same, it took about 1.5 ltr to fill it up. I'm assuming it was empty.

Post by **bmcecosse** » Sun Jan 04, 2009 6:37 pm

Hmmm - they are quite robust - let's hope there was at least some oil in there and the gears splashed it around ! Must be quite a leak somewhere to lose almost all the oil!

Post by **jothina** » Sun Jan 04, 2009 6:46 pm

sorry to hijack the thread, my box has just started to jump out of 4th gear, it happened twice today on a 60 mile round trip,is there an easy fix for this or will i soon need a new box. ? apart from this the box is quiet and seems quite sound

john

Post by **bmcecosse** » Sun Jan 04, 2009 6:53 pm

Start looking for another box! The only 'fix' will be a full rebuild - although that is a relatively unusual (but not unheard of) fault - they usually jump out of second gear as the first symptom of failure.

Post by **jothina** » Sun Jan 04, 2009 6:55 pm

ok thanks

Post by **bmcecosse** » Sun Jan 04, 2009 6:57 pm

Some on ebay at the moment (and in your general direction too IIRC)- although some are smooth case 948 type. Might do a turn while your own box is rebuilt ?
Here's a link to two that may be of interest - http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :IT&ih=019

Post by **nslocomotive2** » Sun Jan 04, 2009 9:57 pm

Yea I dont, know there is a large ish leak comming from the engine too so I wont know for sure untill i check it again, I will run it to work for a few days then check the level again, I wonder if it had a service at some point and someone could have forgoten to fill it back up after drainning the oil off. Looking around where its sat there is no sign of leakage from the gearbox, but I suppose it leaks during use so if thats the case I need to drive it

and then take a look, but its much quieter now

Post by **les** » Sun Jan 04, 2009 10:22 pm

I wonder if it had a service at some point and someone could have forgoten to fill it back up after drainning the oil off

There are such people about, but serious oil loss can come from the rear tail seal, if the bush is badly worn the seal suffers excessive wear.