I'm in the process of restoring a 1968 Series 1. P6B and have been a lurker on this forum for some time, so I thought it was about time to join. I purchased my Rover in 1978 and I carried out a partial restoration in 1984 with new wings all round (they were off the shelf in those days, well under £60) and engine rebuild with new cam, rockers, followers, timing chain and gears plus glaze busting with new rings and the usual big end and main shells. A change of job which included a company car plus driving 24000 miles a year reduced my use of the Rover. Fast forward to 2023 and it has sat in the garage for 17 years and most of you will realise it has not done it any favours. I'll post some pictures of how the second restoration is going very soon but my first question involves the brake master cylinder for single line systems.
If you check the parts manuals, GMC 303 is for the 2000's and GMC 307 is for the 3500's, what's the difference? I ask because I've found a difference in the union type from the gravity fed brake fluid reservoir. To cut a long story short, when I first purchased the car way back in 1978 the union bore for the reservoir had a reverse double flare fitting machined into it (as you would get from a flexible hose connection end.) I purchased a Unipart GMC 307 which at the time assumed was identical and fitted the pipe as usual. On dismantling last month due to my ongoing renewal of the braking system it has a single flare. I purchased a new master cylinder from an eBay dealer who I've used many times who specialises in P6 parts and his Lucas stamped master cylinder has a double flare? A new hose and 1/4" down-pipe to this from Winns has a single flare so ideally this is not the same. I have a brake flaring tool kit so I made a second flare to suit the profile in the master cylinder. So my question is, what is correct and how is has this mismatch occurred, bore sizes on the master cylinders are all 0.875 so no apparent difference there.
I appreciate that a single flare under average compression tightness will work under a gravity fed system but as a time served engineer it is not really correct.
Anyway a question for the single line brake "experts". There seems to be a one size fits all for both the 2000 and the 3500 these days.
Regards Tony
If you check the parts manuals, GMC 303 is for the 2000's and GMC 307 is for the 3500's, what's the difference? I ask because I've found a difference in the union type from the gravity fed brake fluid reservoir. To cut a long story short, when I first purchased the car way back in 1978 the union bore for the reservoir had a reverse double flare fitting machined into it (as you would get from a flexible hose connection end.) I purchased a Unipart GMC 307 which at the time assumed was identical and fitted the pipe as usual. On dismantling last month due to my ongoing renewal of the braking system it has a single flare. I purchased a new master cylinder from an eBay dealer who I've used many times who specialises in P6 parts and his Lucas stamped master cylinder has a double flare? A new hose and 1/4" down-pipe to this from Winns has a single flare so ideally this is not the same. I have a brake flaring tool kit so I made a second flare to suit the profile in the master cylinder. So my question is, what is correct and how is has this mismatch occurred, bore sizes on the master cylinders are all 0.875 so no apparent difference there.
I appreciate that a single flare under average compression tightness will work under a gravity fed system but as a time served engineer it is not really correct.
Anyway a question for the single line brake "experts". There seems to be a one size fits all for both the 2000 and the 3500 these days.
Regards Tony
