Spit 1500 gearbox fail..

[wimpus]

Hi all.

Saturday when setting off at traffic light suddenly lost all gears .

Stopped and could drive off again but noises..

 

Sunday did a little trip, all was fine sort off.

 

Monday went to work, in traffic again lost all gears and horrible noises.

At the evening went to home and was sort of OK.

In the evening went back to work as I could use the garage space there + a day off.

On the way to there gearbox and prop started to bang.

Stopped, drove back off.. heavy knocking sounds in all gears exeot 4th.

 

Took the box out yesterday evening and fitted my spare rebuild box today.

 

This evening i really wanted to know what failed.

Gearbox sometimes locked up etc and very stiff..

I was shocked ! 

 

-laygear is scrap

-laygear shaft is scrap

-mainshaft tip is worn.

 

Gearbox oil was changed a few weeks ago and no swarf on it then.

[thescrapman]

That really has self destructed. 

Hard to work out whether the 2 issues are interconnected, or just 2 bits of wear that happened to reach an issue simultaneously.

Are you intending to rebuild that box or look for a better one?

Just to add, the prices of mainshafts has rocketed (well in the U.K.) recently, I wonder if there is supply issue.

[johny]

wow and of course its a big tip mainshaft! I knew our gearboxes can deteriorate very quickly but even so.... What condition are the ball race bearings in?

[johny]

Another thing, are both the oil way through the layshaft and the hole in the laygear clear? I wonder if oil flow to the laygear bearings was restricted somehow.... As I say once the few thou of case hardening on the layshaft is worn through things rapidly go downhill☹️

[wimpus]

10 hours ago, johny said:

wow and of course its a big tip mainshaft! I knew our gearboxes can deteriorate very quickly but even so.... What condition are the ball race bearings in?

Front has a bit of play.

Rear not bad.

 

2or 3 years ago I had the front bearing fail on this box. (Then fitted japaneese KSM bearings)

Gearbox was a recon from a belgian supplier 4 to 5 years ago.

[johny]

The quality of replacement layshafts has been questioned due to the lack of case hardening depth and hardness so Im going to use a good secondhand original (hopefully) one for my Vitesse gearbox rebuild when required. I certainly drive it gently in the lower gears and fortunately the 2L six engine allows me to get into and stay in 4th most of the time without being too detrimental to the fun😍 

[Pete Lewis]

with all the boxes i have handled over the years i have never seen a spindle so bad  so my view is its a soft shaft and the chicken and egg 

failure mode the rest of the box has suffered from the cluster /shaft deterioration the shaft has worn so much the needles had escaped within

the layshaft cluster bore as the shaft is wrecked along its length not just the wear zone 

has the debris attacked the tooth profile ???      there is always play on the input bearing it lost some support from the failed eip needles 

but has to rely on the flywheel spigot fot its support you must clean and check the OD bearings and filters 

seems you have got a real mincing machine   what a bummer .

Pete

[wimpus]

1 hour ago, Pete Lewis said:

with all the boxes i have handled over the years i have never seen a spindle so bad  so my view is its a soft shaft and the chicken and egg 

failure mode the rest of the box has suffered from the cluster /shaft deterioration the shaft has worn so much the needles had escaped within

the layshaft cluster bore as the shaft is wrecked along its length not just the wear zone 

has the debris attacked the tooth profile ???      there is always play on the input bearing it lost some support from the failed eip needles 

but has to rely on the flywheel spigot fot its support you must clean and check the OD bearings and filters 

seems you have got a real mincing machine   what a bummer .

Pete

Inspected gears and all seem good.

Spigot bush was changed now to as the old one was still original.

I had 2 gearboxes fail at the front bearing falling apart etc. + wrecking the clutch..

 

Overdrive sump, filter, high pressure filter & solenoide + passage ways where cleaned yesterday.

 

Only thing I can think what happened is that the laygear shaft wasnt good quality.. 

So started to wear and needles escaped.

 

A month ago or sometime I had changed the gearbox oil + OD serviced, nothing really bad to find then .

 

[Pete Lewis]

apart from poor quailty the only other things to fail a front bearing race is lack of oil levels or storing the box stood up on its bell housing , 

this lets any wear residue gravitate into the input shaft bearing 

so always store a box the right way up not up ended ... its an olde  problem with any gearbox 

Pete

[wimpus]

6 hours ago, Pete Lewis said:

apart from poor quailty the only other things to fail a front bearing race is lack of oil levels or storing the box stood up on its bell housing , 

this lets any wear residue gravitate into the input shaft bearing 

so always store a box the right way up not up ended ... its an olde  problem with any gearbox 

Pete

Do store the spare box like it would sit in the car.

 

Checked the laygear shaft.

Seems the oil hole is clear.

Checked all gears.. but first motion/4th gear bearing surface is bad to..

 

[johny]

the poor quality aftermarket layshaft problem is backed up by the fact that some gearbox specialists have made their own so the depth and hardness in the manufacturing process can be guaranteed.... 

[johny]

Wonder if you need this Wimpus:

https://www.ebay.co.uk/itm/TRIUMPH-SPITFIRE-MK4-1500-LAYGEAR-CLUSTER-15-Teeth-1970-80-154829-NEW-OLD-STOCK/233707374819?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20160323102634%26meid%3D56d0c0856eef40bcb1ea3d8debf349d0%26pid%3D100623%26rk%3D1%26rkt%3D5%26sd%3D202724533817%26itm%3D233707374819%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganic%26brand%3DTriumph&_trksid=p2047675.c100623.m-1

[wimpus]

On 26/11/2020 at 15:28, johny said:

Wonder if you need this Wimpus:

https://www.ebay.co.uk/itm/TRIUMPH-SPITFIRE-MK4-1500-LAYGEAR-CLUSTER-15-Teeth-1970-80-154829-NEW-OLD-STOCK/233707374819?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20160323102634%26meid%3D56d0c0856eef40bcb1ea3d8debf349d0%26pid%3D100623%26rk%3D1%26rkt%3D5%26sd%3D202724533817%26itm%3D233707374819%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganic%26brand%3DTriumph&_trksid=p2047675.c100623.m-1

I have bought that Laygear .

I already had seen it before you posted it

[johny]

well done, it was a good price! And if you find a source of quality layshafts to match let us know👍

[wimpus]

What someone told me, but unsure if its possible.

 

To turn the mainshaft and input on a lath, so a oversized/metric bearing fits.

Is this possible? 

Is the shaft hard enough ? 

[Pete Lewis]

they are only case hardened   i doubt any machining would work   

 

and this doesnt stack up  as machining  so the spigot gets smaller the stem gear bore gets bigger 

fitting a full caged needle set blocks the oil hole    Ive seen some wonderous ideas none lasted 

Pete

[johny]

You could reduce the tip of the mainshaft to fit a metric bearing inner race sleeve although you would have to decide the best way of fitting it. Then bore the input shaft to take a metric needle roller bearing including outer race however, as Pete says, you would have to find a way to maintain the oil feed through the hole from the exterior of the gear.... 

[Clive]

18 minutes ago, johny said:

You could reduce the tip of the mainshaft to fit a metric bearing inner race sleeve although you would have to decide the best way of fitting it. Then bore the input shaft to take a metric needle roller bearing including outer race however, as Pete says, you would have to find a way to maintain the oil feed through the hole from the exterior of the gear.... 

There is info on this on teh sideways forum. IIRC a hole drilled (easier said than done) in the root of the tooth will pump oil into the bearing. Doesn't need much.

A friend machined the tip of his mainshaft round, and made a PB bush to replace the bearing. Shouldn't work of course, but 110K later it is still fine. He did cut a long scroll in the bronze to feed oil in. It is a GT6 box fitted behind a mk3 spit engine. Moderately driven. (input shaft was a spit and GT6 shaft cut/welded to suit)

[Nick Jones]

Layshaft made of cheese and the rest of the damage due to the swarf in the oil.

Mainshaft tip can be machined down so that a proprietary bearing sleeve can be pressed on. It’s hard but machinable with the right inserts. Likewise with the input shaft bore, though you have to be careful as it’s already a big hole. Maybe use a a drawn cup (Torrington) roller bearing - if you do that you must drill through the root of the gear to the back of the bore so it gets lubricated. Will die very quick if not.

Probably a lot of fine swarf in the overdrive too.

Nick

[johny]

Maybe it could be done with one of these but being 15 x 27mm it will need quite a bit of metal removing: 3mm taking off the tip diameter and 2mm from the mainshaft bore diameter...

[wimpus]

12 hours ago, Nick Jones said:

Layshaft made of cheese and the rest of the damage due to the swarf in the oil.

Mainshaft tip can be machined down so that a proprietary bearing sleeve can be pressed on. It’s hard but machinable with the right inserts. Likewise with the input shaft bore, though you have to be careful as it’s already a big hole. Maybe use a a drawn cup (Torrington) roller bearing - if you do that you must drill through the root of the gear to the back of the bore so it gets lubricated. Will die very quick if not.

Probably a lot of fine swarf in the overdrive too.

Nick

Hi Nick !

I had opened up the OD to clean it, removed the sump, high pressure filter, solenoid and blew it all clean.

Where the oil runs in the od it was bad.

So got it all out and cleaned it with brake fluid.

 

After my few fails of gbox front bearings.. it was the same to.

 

I knew it started to collect swarf as when OD went 'out' it would not go out nicely anymore..

 

Mainshaft ive found.. but £200..

 

Really been thinking of buying a full OD gearbox as spare.. last year when I was in the UK they costed £350.

[Pete Lewis]

i found a box ( bought for core )  where the mainshaft spigot had been drilled out and ground the take a ground slug to replace the spigot  , but with nothing to hold it in place it had minced  the bore /bearing in the input/stem wheel    sort if inventive but ...didnt work , the rest of the box had single /3rail mixed up hubs and sleeves  

someone spent a lot to get know where 

pete

[johny]

Ive got one in progress at the moment where the tip has been turned down and a bearing inner sleeve loctited on. It looks pretty good but Ive just still to sort out the input shaft to match it now....

[Nick Jones]

12 hours ago, wimpus said:

Really been thinking of buying a full OD gearbox as spare.. last year when I was in the UK they costed £350.

Yes..... but using the same cheese layshaft probably...... and who knows what other “repairs”.  The occasional driver won’t find out for years, but someone who really uses their car as you do will get trouble just after the warranty expires. Could be ok, but you don’t know without looking inside.

Nick

[daverclasper]

My Vitesse had a J Type fitted when I bought it. Apparently fitted by Canley back in about 03. I had a first gear noise, so stripped it down (before I learned this is not unusual in a bitza box to take the J Type).  According to old MOT's the car had done about 25,000 miles since this box was fitted.

The only damage was the lay shaft and lay cluster that had started to go, though the lay gear was able to be reclamed.

I had the rebuild and a few upgrades done by Mike Papworth who also used a second hand original layshaft.

He apparently did the original box for Canley (don't know if he was using the crap shafts then, or car had had a lot of stick?).

The lay problem was not makng any noise that I could hear.

Dave