MLU FORUM  

Go Back   MLU FORUM > MILITARY VEHICLES > The Armour Forum

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 18-09-18, 04:15
Malcolm Towrie Malcolm Towrie is offline
Registered User
 
Join Date: Aug 2015
Location: Whitby, Ontario, Canada
Posts: 306
Default M8 Greyhound Brake Fluid?

Hi, I'm working on dragging brakes on a Greyhound. We use DOT 3 in the brake system, based on a Google search saying "HB" fluid should be used. (The 1943 manual we have says "information not available at this time".)

I just dismantled a wheel cylinder and found the u-cup seals in good condition but maybe a bit soft and swollen. They make the pistons quite hard to push by hand through the bore, so I was wondering if we should have been using a mineral oil.

Malcolm
Reply With Quote
  #2  
Old 19-09-18, 01:23
Malcolm Towrie Malcolm Towrie is offline
Registered User
 
Join Date: Aug 2015
Location: Whitby, Ontario, Canada
Posts: 306
Default

I got the answer from Brian Asbury. It uses dot 3 brake fluid.
Malcolm
Reply With Quote
  #3  
Old 20-09-18, 00:42
Frank v R's Avatar
Frank v R Frank v R is offline
Registered User
 
Join Date: Dec 2011
Location: pefferlaw , ont
Posts: 469
Default

always pump the brakes after shut down , that way you will not be looking for where the brake fluid has gone,
Reply With Quote
  #4  
Old 20-09-18, 04:10
Malcolm Towrie Malcolm Towrie is offline
Registered User
 
Join Date: Aug 2015
Location: Whitby, Ontario, Canada
Posts: 306
Default

Hi Frank,
It looks like you need a couple of seals to leak in the Hydrovac unit between the hydraulic circuit and the vacuum reservoir for this to happen. I haven't noticed our M8 losing brake fluid, so maybe the seals are good? But it may also be because sadly it rarely gets driven. I'll keep an eye out for losing fluid.
Malcolm
Reply With Quote
  #5  
Old 26-09-18, 18:57
Rob Cassin Rob Cassin is offline
Registered User
 
Join Date: Dec 2017
Location: West Point, NY
Posts: 22
Default M8 brakes

DOT 3 is correct for your M8 and for just about any 1940's hydraulic brake system. You should never use mineral oil in a brake system and you should do your best to keep any traces of oil from entering your brake system. Oil is actually a cause of deteriorated brake system seals.

-=BK
Reply With Quote
  #6  
Old 27-09-18, 02:32
Malcolm Towrie Malcolm Towrie is offline
Registered User
 
Join Date: Aug 2015
Location: Whitby, Ontario, Canada
Posts: 306
Default

Thanks, Rob. I would not have considered using mineral oil in a brake system, until I worked on some CVRTs. They use mineral oil, which rattled me a bit! So now I make sure what is correct before working on any brake system.

Malcolm
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
RCD's M8 Greyhound John McGillivray The Armour Forum 14 03-02-12 15:08
M8 Greyhound in Australia. Ryan The Armour Forum 15 14-09-09 13:32
Hydraulic fluid question Bruce Parker (RIP) The Restoration Forum 11 21-06-07 07:45
Iltis cross reference for CGSB-3-GP-510 brake fluid Stuart Fedak Post-war Military Vehicles 2 13-06-06 03:18
Brake fluid John McNarry The Restoration Forum 4 26-03-05 18:39


All times are GMT +2. The time now is 15:56.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright © Maple Leaf Up, 2003-2016