Early Series I 240Z Clutch Master Cylinder touching Windshield Washer Bottle...

[redzedsled]

Hello All!

I have rebuilt what I think is a Series I 240Z Clutch Master Cylinder made by Nabco (5/8" bore) for my 12/70 built car. After rebuilding and installing I noticed that it touches the Windshield Washer Bottle. Having said that, I consulted the Factory Service Manual and it shows a cross section illustration for two separate and distinct profiles (see attached images). On page CL-6, Figure CL-15, the reservoir is shown being located in the center area of the Master Cylinder. Yet if you refer to page CL-7, Figure CL-16, you will note that the reservoir is at the frontmost portion of the Master Cylinder.

I have tried to research other threads, but there seems to be an absence of good images to refer to. I have understood that a 260Z Clutch Master Cylinder may be slightly longer than than of the 240Z units, is it possible it might be for a 260Z? I was always led to believe that the 260Z units moved the reservoir towards the center. Could someone please chime in on the known differences between model years.

It should also be noted that there was a recall dated 7-11-1972 which "introduced a redesigned valve case. New part number 30610-E4200 more positively prevented air from entering the cylinder from the bottom of the reservoir" as quoted in Wick Humbles 'How to Restore Your Datsun Z-Car'. In fact, as is shown in his book on page 138 on the upper left hand image, it clearly shows a replacement Master Cylinder with the reservoir located in the center of the unit.

There is at least 8 different part numbers within the microfiche including 30610-E4100, E4101, E4200, E4201, N4200, E4301, N4000 and N4001. Could anyone please share some images they may have of their CMC installed and its proximity to the Windshield Washer Bottle. The current Master Cylinder I have installed measures about 4-1/8" from the firewall to the end of the aluminum valve body. Any help is greatly appreciated and valuable for other members of this club.

Please note on the very last image that there is strong evidence that clearance was not an issue with the washer bottle.

Edited September 8, 2014 by redzedsled

[jfa.series1]

Here's my replacement clutch master, also a 5/8" bore - visible on the side. Unfortunately there is no mfr. brand on the casting. It was purchased from RockAuto about 3 years ago.

[redzedsled]

Here's my replacement clutch master, also a 5/8" bore - visible on the side. Unfortunately there is no mfr. brand on the casting. It was purchased from RockAuto about 3 years ago.

This looks nice and clean. Just having the reservoir towards the firewall in this design greatly improves the clearance. I wonder if any other members have had similiar issues with the early Clutch Master Cylinder.

Perhaps it might be better judgement to get a newer CMC, whatwith the Nissan recall, and gain the clearance desired. Thanks for your response!

[CanTechZ]

My CMC was replaced in 1983 with a center reservoir style, the dealer invoice shows P/N 30610-Y4401. I'm not sure why there is a "Y" in the part number? It's a Nabco and the overall length of the alum. body measures 4.5". Here's a pic showing the clearance with the WS washer reservoir. The clearance between the end of the CMC alum. body and the WS washer reservoir is almost 3/8".

HTH Mike

[CanTechZ]

I did a little more digging in my old parts invoices and it looks like the CMC P/N 30610-Y4401 might be from one of my 510's. However I do have an invoice from 1979 where I had the local Datsun dealer replace my CMC with P/N 30610-N4001, IIRC that was the only time it was changed. Sorry for the confusion.

[redzedsled]

I did a little more digging in my old parts invoices and it looks like the CMC P/N 30610-Y4401 might be from one of my 510's. However I do have an invoice from 1979 where I had the local Datsun dealer replace my CMC with P/N 30610-N4001, IIRC that was the only time it was changed. Sorry for the confusion.

Thanks for your input Mike. There are a vast number of other Nissan part numbers that are a 5/8" bore with many being compatible with other Datsun models: 30610-N4000, 30610-N4001, 30610-N6001, 30610-U750A, 30610-U7517, 30610-U7510, 30610-H5802, just to name a few. I like the idea of finding a Nabco brand like the one you have, with the mid-reservoir.

[Zup]

New OE Fits Nissan Datsun 240Z 260z 280z 510 Clutch Master | eBay

I have purchased from Carmella555555 in the past and have nothing but very satisfactory experiences to report.

This is a 5/8" bore Nabco clutch master cylinder and will not interfere with your washer bottle.