Jon Clark Posted September 15, 2020 Report Share Posted September 15, 2020 Hi Folks, I recently fitted a new TRW master cylinder to my 5. Having filled the reservoir and starting to bleed the brakes, the first few depressions of the pedal failed to pump any fluid. On taking the cylinder off again, the piston was stuck in the bore, obviously not having returned from the first push on the pedal. With gentle persuasion (tapping on the end of the cylinder) I eventually managed to get the piston to return. However, on pushing it back in the bore manually it stuck again. Repeated this a few times before giving up and returning the unit to Moss. They kindly couriered a replacement out to me promptly. I tried this one on the bench and the piston appeared to be moving smoothly in the bore. However, on fitting to the car exactly the same problem occurred as with the first unit. After removal, again I managed eventually to get the piston to return but on pushing it in again manually it stuck again and no amount of persuasion has released it again. Is anyone aware of a similar problem with any recent TRW units or have any advice to offer? Quote Link to post Share on other sites
RogerH Posted September 16, 2020 Report Share Posted September 16, 2020 Hi Jon, welcome to the forum. This is a new defect to me. Have you spoken to Moss regarding the second MC. It could be a batch problem - replacements off the shelf may all have the same problem. I have sent you a PM - look for Red letter in top right hand corner and click on it. Roger Quote Link to post Share on other sites
rcreweread Posted September 16, 2020 Report Share Posted September 16, 2020 Jon - Have you still got the original master cylinder? If so, send it to these guys who will recondition it - http://www.pastparts.co.uk/index.php?route=information/contact No connection other than a satisfied customer Cheers Rich Quote Link to post Share on other sites
Jon Clark Posted September 16, 2020 Author Report Share Posted September 16, 2020 Thanks Roger / Rich, Roger - I had been trying to speak to Adam Chignall at Moss for a few days and we finally caught up today. He agreed that it sounds highly unusual and therefore potentially a batch problem. Obviously they will check the returned units in due course but this may take a while. We agreed it doesn’t seem worth having another from their existing stock until it is known if it is a batch fault. Re. the PM, I can’t see the red letter you mention, can you clarify? Rich - thanks for the link, I had not heard of Past Parts. I will be dismantling my old master cylinder and if the bore is ok I will probably rebuild it myself but goood to know of PP anyway. Cheers, Jon Quote Link to post Share on other sites
RogerH Posted September 16, 2020 Report Share Posted September 16, 2020 Hi Jon, the PM is at the top right hand corner of this page. The old format displayed a red envelope. perhaps this new display does not. Click on the envelope and see my message. Roger Quote Link to post Share on other sites
rcreweread Posted September 16, 2020 Report Share Posted September 16, 2020 39 minutes ago, Jon Clark said: Thanks Roger / Rich, Roger - I had been trying to speak to Adam Chignall at Moss for a few days and we finally caught up today. He agreed that it sounds highly unusual and therefore potentially a batch problem. Obviously they will check the returned units in due course but this may take a while. We agreed it doesn’t seem worth having another from their existing stock until it is known if it is a batch fault. Re. the PM, I can’t see the red letter you mention, can you clarify? Rich - thanks for the link, I had not heard of Past Parts. I will be dismantling my old master cylinder and if the bore is ok I will probably rebuild it myself but goood to know of PP anyway. Cheers, Jon Jon - as I understand it, Past Parts ream out the bore and fit a stainless steel liner, bead blast the outside and rebuild with known quality seals and new parts as necessary, so a refurbed unit should be as good if not better than an original new unit. Cost is obviously more than your TRW repro but how much hassle have you already had and the historic evidence of the longevity of these repros is not that encouraging, but ultimately the choice is yours. If the bore is corroded, don't throw it away. just put it on here and someone will snap it up! Cheers Rich Quote Link to post Share on other sites
AndyK Posted December 8, 2022 Report Share Posted December 8, 2022 Coming to this thread a bit late. In the process of finishing full refurb of my TR6. Fitted new brake master cylinder and tried to bleed. First press OK then goes soft. Piston stuck in barrel. Managed to free with air line but stuck again. Replaced unit and same thing happened with new one. Both were TRW units. Did a lot of searches but found nothing to explain problem. Then when I was looking to get my 3rd unit found this on TRGB web site. BRAKE MASTER CYLINDER FOR TR5/6. **IMPORTANT** PLEASE READ THE FOLLOWING FITTING DISCLAIMER... THERE IS ONLY ONE MANUFACTURER OF BRAKE MASTER CYLINDER FOR THESE MODELS - TRW. THESE ARE CHEAP UNITS WHICH, 3 YEARS AGO WE WERE SELLING FOR NEARLY £200 +VAT. WHEN FITTING, THERE IS A VERY HIGH POSSIBILITY THAT, IF THE PEDAL IS DEPRESSED COMPLETELY TO THE BULKHEAD, THAT THE SHUTTLE INSIDE THE MASTER CYLINDER CAN STICK AND MAKE THE UNIT UNUSABLE. IF THIS HAPPENS THEN IT IS NOT COVERED BY ANY WARRANTY. WHEN BLEEDING THE SYSTEM THE BRAKE SYSTEM NEEDS TO BE PARTIALLY BLED ALTERNATIVELY BETWEEN THE FRONT AND REAR HALVES OF THE SYSTEM USING 1/2 PEDAL PRESSES UNTIL THE SYSTEM IS "FULL" OF FLUID. AFTER THIS PROCESS, THE BRAKES CAN BE BLED NORMALLY, STARTING AT THE N/S REAR, BUT ONLY BY PRESSING THE PEDAL 2/3rds OF THE FULL STROKE. THESE INSTRUCTIONS SHOULD COME WITH THE UNIT WHEN IT ARRIVES AND NEED TO BE FOLLOWED, TO THE LETTER. So basically TRW unit is pretty useless but is the only one available. Has anyone else had the same issue? Quote Link to post Share on other sites
Richardtr3a Posted December 8, 2022 Report Share Posted December 8, 2022 Past Parts are the best choice and have done all my hydraulics. The problems have now gone away. Give them a try. We are talking about brakes which can cause serious damage if the cylinder fails in use. Good luck Richard & B Quote Link to post Share on other sites
harlequin Posted December 9, 2022 Report Share Posted December 9, 2022 I have had a 2 year old TRW master cylinder fail! Which was something that I don't want to re experience so now will only use Past Parts refurbished components. As has been mentioned its a little bit more expensive to go this way and it's not an off the shelf replacement so you have to wait, but it's quality parts that are reliable. I have no connection with Past Parts apart from being a customer. George Quote Link to post Share on other sites
harrytr5 Posted December 9, 2022 Report Share Posted December 9, 2022 Really thought all this nonsense was sorted years ago but still happening today. I and others have had their original master cylinders rebuilt by Past Parts etc and work as they should. Regards Harry Quote Link to post Share on other sites
John Bracher Posted December 9, 2022 Report Share Posted December 9, 2022 2 hours ago, harlequin said: I have had a 2 year old TRW master cylinder fail! Which was something that I don't want to re experience so now will only use Past Parts refurbished components. As has been mentioned its a little bit more expensive to go this way and it's not an off the shelf replacement so you have to wait, but it's quality parts that are reliable. I have no connection with Past Parts apart from being a customer. George Aside from the waiting time, can anyone quantify what is a "little more expensive" please? If appropriate, and the wait is not months, this task could go on the 'Winter layup' list....... Quote Link to post Share on other sites
stuart Posted December 9, 2022 Report Share Posted December 9, 2022 8 minutes ago, John Bracher said: Aside from the waiting time, can anyone quantify what is a "little more expensive" please? If appropriate, and the wait is not months, this task could go on the 'Winter layup' list....... FWIW Past parts will only refurb original cylinders and wont touch the TRW ones. Stuart. Quote Link to post Share on other sites
Waldi Posted December 9, 2022 Report Share Posted December 9, 2022 Hi John, I ordered mine from PP a couple of years ago, they came back within 3 weeks….to Holland! And this was including “yellow zinc” plating. Think they have some stock as well for exchange. Think I paid 80-100 pounds each. Waldi Quote Link to post Share on other sites
John Bracher Posted December 9, 2022 Report Share Posted December 9, 2022 Thanks Gents. That seems 'acceptable'. I think I have a Girling one in a shed, so maybe send that one away?? Quote Link to post Share on other sites
stuart Posted December 9, 2022 Report Share Posted December 9, 2022 2 hours ago, John Bracher said: Thanks Gents. That seems 'acceptable'. I think I have a Girling one in a shed, so maybe send that one away?? If you have a Girling original then yes thats whats needed. Stuart. Quote Link to post Share on other sites
PodOne Posted December 9, 2022 Report Share Posted December 9, 2022 Hi John I bought one from Conrad a few years ago now which had being reconditioned by Past Parts. Try contacting him he might just have one on the shelf. Out of interest I have the one that came with the car how do you tell if its an original rather than a TRW repro? Andy Quote Link to post Share on other sites
harrytr5 Posted December 10, 2022 Report Share Posted December 10, 2022 Think the TRW one has Lucas embossed on it but can not be sure. I had my original done (Past Parts) in a silver finish around £200 (That included one from his stock as mine was damaged in the post) Much dearer of course but works! Quote Link to post Share on other sites
RogerH Posted December 10, 2022 Report Share Posted December 10, 2022 (edited) The 'original' Lucas MC had LUCAS embossed on it. There is an original on EBAY at the mo' for £69. Would make a good base for refurb M/C Roger Edited December 10, 2022 by RogerH Quote Link to post Share on other sites
stuart Posted December 10, 2022 Report Share Posted December 10, 2022 That’s not an original Roger, this is an original Quote Link to post Share on other sites
RogerH Posted December 10, 2022 Report Share Posted December 10, 2022 Ha ha - how many originals are there. Roger Quote Link to post Share on other sites
ntc Posted December 10, 2022 Report Share Posted December 10, 2022 Odd this I have fitted three of these in the last four years and not had any problems. Quote Link to post Share on other sites
harlequin Posted December 12, 2022 Report Share Posted December 12, 2022 On 12/10/2022 at 8:19 PM, ntc said: Odd this I have fitted three of these in the last four years and not had any problems. The one I had was fine for about 2 years, I then had some brake work done which must have altered the travel of the master cylinder piston. Within 100 miles of having this work done the master cylinder failed. When I stripped it down I found the seal was stuffed and there was a distinct step in the bore. My assumption was that the cylinder material was to soft and was wearing, then when the stroke changed the seal was crossing the wear step which wreaked it. End result no brakes. George Quote Link to post Share on other sites
astontr6 Posted December 27, 2022 Report Share Posted December 27, 2022 On 9/16/2020 at 10:17 AM, rcreweread said: Jon - Have you still got the original master cylinder? If so, send it to these guys who will recondition it - http://www.pastparts.co.uk/index.php?route=information/contact No connection other than a satisfied customer Cheers Rich +1. I would not buy a new TRW master cylinder. Problems with their M/Cs extend into other marques. There seems to be a lack of QA in that company. Quote Link to post Share on other sites
stuart Posted December 28, 2022 Report Share Posted December 28, 2022 11 hours ago, astontr6 said: +1. I would not buy a new TRW master cylinder. Problems with their M/Cs extend into other marques. There seems to be a lack of QA in that company. Last time this problem came up a few years ago it was traced to a rogue batch of Chinese fakes, I suspect thats probably the case this time too. There is a lot of genuine TRW ones in service doing fine. Stuart. Quote Link to post Share on other sites
RogerH Posted December 28, 2022 Report Share Posted December 28, 2022 Can the fakes be identified??? Roger Quote Link to post Share on other sites
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