Sherpa Brake servo for Tr7

moestr7v8 · Postby **moestr7v8** » 08 Jun 2013 22:37

Hi all I am in need of some advice,a while back I bought what was advertised as an uprated servo for the v8,this is new and the info on the servo was that it was for a Sherpa van,I have since been told that it is not an uprated one anybody able to help out on this please?
There is a plate on the servo with this number on it,L14GT LBDKZ026B6.
I am sorry but I am unable to supply a photo,I have tried before but no chance,if anybody can help to clear up my confusion I will be very grateful.
Cheers
Moe

busheytrader · Postby **busheytrader** » 09 Jun 2013 08:16

Hi Moe,

Was the servo bought separately or is it a servo / master cylinder combo you're describing?

Adam

jeffremj · Postby **jeffremj** » 09 Jun 2013 10:11

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by moestr7v8

Hi all I am in need of some advice,a while back I bought what was advertised as an uprated servo for the v8,this is new and the info on the servo was that it was for a Sherpa van,I have since been told that it is not an uprated one anybody able to help out on this please?
There is a plate on the servo with this number on it,L14GT LBDKZ026B6.<hr height="1" noshade id="quote"></blockquote id="quote">I also bought one, purporting to be a Sherpa servo, off ebay. It should be uprated as, I believe, assistance is related to servo diameter - the TR7 is 20cm, my Sherpa is 23cm and my Rover V8 (on the TR7V8) is 25cm. Here is a picture of my unfitted Sherpa servo - if I ever fit it, I would swap the reservoir with a TR7 version and remove that metal block 'thing'. The lettering on the plate is LBDK7D032A and LBDKJD014B:

moestr7v8 · Postby **moestr7v8** » 09 Jun 2013 15:51

Hi Adam I bought the unit without the master cylinder it was advertised on ebay as an uprated servo for a TR7/8 and listed as a Sherpa van servo.
Jeff I will measure the diameter of the unit and compare it with the one on the 7v8.
Cheers
Moe

moestr7v8 · Postby **moestr7v8** » 09 Jun 2013 18:53

just checked the size of the servo unit, the one on the car is 20 cms and the new one is 23,by the way did you put the one on your car Jeff, if so where did you get from as at 25 cms surely that must be an uprated one do you think?
Cheers
Moe

TR Tony · Postby **TR Tony** » 09 Jun 2013 19:42

For a given amount of manifold vacuum, a larger servo will give more assistance to the brake effort, which we feel as less effort required by the driver on the pedal to produce the same pressure at the pads.

Generally you can use the diameter of the servo as a good guide to the diameter of the diaphragm in the servo, which is the part that actually does the work. So your 23cm servo should give a higher level of assistance than the 20cm, but less than the 25cm.

Tony

1981 TR7 FHC Cavalry Blue
1980 TR7V8 DHC Jaguar Regency Red - sadly sold!
1977 TR8 FHC EFI Factory development car Inca Yellow

jeffremj · Postby **jeffremj** » 09 Jun 2013 20:25

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by moestr7v8

just checked the size of the servo unit, the one on the car is 20 cms and the new one is 23, by the way did you put the one on your car Jeff, if so where did you get from as at 25 cms surely that must be an uprated one do you think?<hr height="1" noshade id="quote"></blockquote id="quote">The 23cm version is probably the same size as the original TR8 servo and if you can use the TR7 master cylinder, you will get an uprate. I got a Rover V8 servo and had it modified to fit a TR7. IIRC, the TR7 servo has a 2x boost and the V8 a 3x boost. The TR8 (Sherpa) version a 2.5x boost? It is possible that my boost maybe too much as the MOT guy thought something was wrong as it was too soft, although when there is no boost the brake pedal is rock hard [:)]

dursleyman · Postby **dursleyman** » 09 Jun 2013 20:36

I have an uprated one which is not a Sherpa unit (it does not have those two extra mounting studs) its painted black and I measured it roughly at 225mm diameter. It was sold to me as an uprated TR7/8 one and also has the bigger diameter master cylinder at 22.2mm (7/8") which I think confusingly IS a Sherpa size? Sorry I cannot do any more details as I am away from home for a few days but See my picture at...

http://www.forum.triumphtr7.com/topic.a ... C_ID=17631

Russ

1980 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

busheytrader · Postby **busheytrader** » 09 Jun 2013 20:52

I opted to fit a combined uprated m/cylinder and servo to mine to ensure they matched each other (Rimmer had a 25% discount promotion at the time) but mainly because the brake pedal had far too much travel with the Capri front brakes.

I can't find a stamped plate on my servo but the SD1 reservoir came with it as standard.

Adam

saabfast · Postby **saabfast** » 10 Jun 2013 19:05

I bought my upgraded servo & master cylinder from S&S after problems rebuilding my M/C (frozen little piston) and a leaky rebuilt M/C ('they all do that sir'). It came as a complete servo & M/C unit but without the reservoir, I think a Sherpa unit although they seemed reluctant to disclose it. The existing TR7 reservoir pushed in without any problems.

Alan
Saab 9000 Stg 1
Saab 9000 2.3 FPT Auto
Saab 9000 2.3 LPT Auto
'81 TR7 DHC

moestr7v8 · Postby **moestr7v8** » 10 Jun 2013 20:56

Thanks everybody for the input and advice,I am still slightly confused on the issue do I fit the Sherpa servo or look into getting the Rimmers TR8 one?
No harm in trying the one I have first and see if it makes a difference
if not put it back on ebay [}:)]
Cheers
Moe

TR Tony · Postby **TR Tony** » 11 Jun 2013 07:11

Moe, if you use your existing master cylinder with the larger servo you should see (feel!) more assistance from the servo = less pedal effort for you!

Don't see why this should not work for you as long as the new servo physically fits.

Tony

1981 TR7 FHC Cavalry Blue
1980 TR7V8 DHC Jaguar Regency Red - sadly sold!
1977 TR8 FHC EFI Factory development car Inca Yellow

dursleyman · Postby **dursleyman** » 11 Jun 2013 14:44

A word of warning here folks, make sure the master cylinder and servo will fit together properly. Apparently some combinations are not OK due to the rod protruding from the servo being the wrong length for the cylinder.

Russ

1980 TR7 Sprint DHC
Dursley
UK

http://tr7russ.blogspot.co.uk/

kstrutt1 · Postby **kstrutt1** » 11 Jun 2013 19:43

I fitted one of these to mine using the TR7 master cylinder, the push rods which goes into the master cylinder are different lengths, but they are easy to change over, there is a star clip at the base inside the servo, carefully pull it off (I used a hooked tool to lift the spikes up), the rod then pulls out and the new clip can be pushed in with a piece of tube, I did post a few pictures on here when I fitted it.

It does reduce the pedal effort but my old servo to m/cyl seal was leaking so I was not starting from a good point.

kstrutt1 · Postby **kstrutt1** » 11 Jun 2013 19:50

If you search for servo and my ID(kstrutt1) you will find the thread.

Kevin

Anonymous