Overdrive Gearbox Fitted

[Darren Groves]

In the last week I finally fitted the Overdrive gearbox I had in to my Herald 13/60.

 

It was a 3 rail with D-type OD of unknown condition, a bit of a risk just to fit I guess given the only thing I did do to it was change the rear oil seal.

 

The good news is that the overdrive works perfectly, so that will be a huge bonus when off on longer trips, looking forward to less stress on the engine and my wallet with improved economy. The gearbox itself is marginally noisier than the one I took out, but not noticeably so. Gear changes are as smooth up & down if you don't rush them. Now for the not so good news.....

 

1. If you want to make quicker gear changes you can get a little crunch - presumably worn synchro rings?
2. I have some vibration sounding like either exhaust or gearbox itself touching the chassis somewhere. Can't see anything obvious, but on assembly did think the gearbox itself was quite close to front of the mounting plate - are there any known clearance issues on this conversion?
3. I am finding the more angled Spitfire OD gear lever a little weird. The gear lever is much more angled than a Herald one, so when in gears 2 & 4 it seems very low down. Just me needing to get used to it I'm sure, but has anyone else found this a bit odd and changed this somehow? Was the Vitesse OD switch only steering column mounted or did it also use the switch on the gear knob, but with a straighter gear lever?
4. I'll probably rebuild the gearbox in the new year, any comments on the kits available from the usual traders? Do's & don't's maybe?

Cheers

[sulzerman]

Hi Darren

I did this conversion on my 13/60 estate (now sold)

I used the column mounted o/d switch and standard herald straight gearstick. I found this better as I could change in and out of o/d without taking my hand off the steering wheel. Just my personal preference.

Happy motoring

cheers

Paul 

[JohnD]

The switch-on-gear-knob versions suffers from the limited engineering available in the day.   The hole up the stick was so narrow that Triumph had to use wires insulated only with a layer of varnish, which wears off so that the wires short out.   Originally the overdrive was on the same fuse as the guages, so when they failed at the same time, you knew what had happened.

 

The on-column switch uses properly insulated wires, so has no problems from that source, but you have to source one - which I presume you have.

 

The alternative was an on-steering wheel switch.   It needs to be a 'latched' switch (press - on, press again - off) and can be conecetd via a length of 'curly-whirly' cabel in Tourig cars fashion.   I added  a warning light to show when the O/d was on, so that I didn't try to change up into third and get fourth.

See pic. (It's a lap timer on the other spoke)

 

JOhn

 

 

 

PS Once again, I try to post a picture, but the ridiculous and unnecessary limits placed on picture size by the Club frustrate me.    On advice (thank you, John) I have uploaded this pic to the Gallery, but on posting the pic from there, I get "You are not allowed to use that image extension on this community."   It's only 46kb  and exactly 640x480 pixels wide for goodness sake!  

Why should I try to help the Club and my fellow members from over twenty years of experience by posting pics when the Club makes it as difficult as possible to do so?   I'd rather do so on the TRR or CT sites, and I will in future. J.
 

[gt6chris]

John,

 

What are you doing? I have posted pictures without an issue on this forum. I have followed the instructions posted by Kevin, added the image to my gallery and posted without an issue. Anyone listening to you would think it's really difficult which it isn't.

 

Chris

[Darren Groves]

Thanks Paul & John - Will make the change to column switch, seems the best option.

 

John - the error message suggests you are using a format other than jpeg, make sure the file you upload to the gallery has a *.jpg extension. Personally I host all my photos elsewhere and just link to them, but admittedly is a little extra work than just uploading.

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

Any thoughts on the vibration and gearbox rebuild kits from the traders?

[KevinR]

I've had a look around some of the help files, and it would appear that the gallery will allow the majority of popular image types to be posted, plus some I have never heard off.

 

The list of file types that can be posted to the gallery is : gif, png, jpg, jpeg, tiff, flv, f4v, mp4, mov, m4a, m4v, 3gp, avi, wmv, mpg, mpeg, mkv

 

I suspect that this is another default setting that the forum software provides.

 

I am very suprised that TIFF files can be posted, as TIFF files can be crafted to contain a virus payload, and simply opening such a file can infect your computer and infect all the TIFF files on it.

 

The file type that is missing from this list is a BMP file, which is a very inefficient file storage format, with files sizes out of all proportion to the contents, so in my opinion has been quite correctly ommited from the list of allowable file types.  BMP files have no compression what so ever, so take up huge amounts of server disc storage, and more importantly take a long time to down load, so anyone posting BMP files will slow down the viewing experience of anyone tyring to view one - and we have had complaints about slow server response and downloads in the past, and we do not want to go back there again.

 

BMP files are very easy to convert to JPGs using Windows Paint - and there are apps for the iPad and Android tablets to do the same.

[Pete Lewis]

Darren some idea on vibration 

    the tail mount can find the centre plate has bottomed out in the lower bolt cup.

 

     also if a D type has beeen rebuilt there are timing/locatoin marks on the planets which must be aligned with marks on the anulus case this ensures all three have the same best running load conditions , in that if out of syn you only load one of the three planets and this sets up a vibration 

its all in the manual. but the marks are small and hard to find .

 

are you sure the new prop is not bottomed out its telescope ??

 

Pete

[Darren Groves]

Darren some idea on vibration 

    the tail mount can find the centre plate has bottomed out in the lower bolt cup.

 

     also if a D type has beeen rebuilt there are timing/locatoin marks on the planets which must be aligned with marks on the anulus case this ensures all three have the same best running load conditions , in that if out of syn you only load one of the three planets and this sets up a vibration 

its all in the manual. but the marks are small and hard to find .

 

are you sure the new prop is not bottomed out its telescope ??

 

Pete

 

Hi Pete,

 

The prop has a sliding joint and it sits right in the middle of it's travel, so nothing is too stressed in that area. The prop has been altered to fit, so undoubtedly needs a balance, but it's actual a rattle rather than a vibration I'm trying to track down, I didn't phrase the initial question very well.

 

It was a bit reminiscent of when the exhaust touches the chassis, but I'm sure it isn't. The overdrive casing does look quite close to the gearbox mounting plate on passenger side, so wondered if that could be toughing when engine running etc. and if anyone else had to raise the gearbox mount up off the plate a little, or if there's any other area that is prone to fouling the chassis.

 

Cheers

Darren 

[Clive]

Darren, the quality of the rebuild kits is often poor. New synchro rings tend to be made of cheese, so I would be finding a non-od box and stripping it for parts!

New layshaft pins are often rubbish too, record is 3 miles (that was from a main supplier) as it was not hardened at all. They offered a replacement, offer declined.

 

Best approach is to use good original parts, swap synchro rings around and replace what is needed. 

 

(all this is from a man I know who builds excellent gearboxes and now even makes his own gaskets....)

[Darren Groves]

Hi Clive,

 

It did wonder if that was the case with the rebuild kits.Interestingly the 2 biggest suppliers don't offer fully reconditioned units any more only the rebuild kits, not sure if this is related to the quality of the parts available, possibly not wanting to deal with warranty claims on units they've built. People like Mike Papworth have a good reputation in the trade, what does he do for parts I wonder,does he have a different source or stocks of NOS.

 

The gearbox I took out was a 4-Synch Non-OD that was rebuilt back in 2001 and was working fine before removal, could I mix & match parts from both boxes to make a 4-synch OD one or is that wishful thinking?

 

Cheers

[Pete Lewis]

all the internals are the same except the mainshaft ,

 

so mix and match is easy

 

having rebuilt and been involved with manufacturing them Ive seen more gearboxes than i care to remember  ( thats 3 spd to 18spd)  I ran out of any acceptable core and with constant spigot failures ended up with good old Mike to make up a mainshaft and stem gear for the Vit6 with the 18mm spigot and this worked fine till I sold her in June .

 

if the up load works here's a good ( may be upside down ) explanation of whats needed to make sycchro work

 

 

Pete 

 

 

 

[Darren Groves]

Had a very good conversation with Mike Papworth today, he rebuilt the gearbox that I fitted back in 2001 and it was still going strong when I removed it. He said that all synchro rings on the market today are poor and he only uses good used items. The traders I have contacted all say their's are fine and they don't have any issues......interesting.

 

As my existing gearbox was still working fine he suggested swapping out the mainshaft in and bolting the overdrive on the back, gave me ballpark prices for supply only and for him to do the swap. Have to say either option is very tempting as this will give me a known good 4 Synch box (which I'm used to) with added bonus of the overdrive.

 

Alternatively he will supply 2 good synchro rings which I could fit in the box I've just installed.

 

Decision,decisions.....