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Brake line test points

Hi can anyone provide me with the information. On size & thread of brake test points on front boat.
Regards Brian

My bus number (if any): RML 2616

Re: Brake line test points

Brian Thomson
Hi can anyone provide me with the information. On size & thread of brake test points on front boat.
Regards Brian


Have you access to the Walkers manual? Or a copy of the LT maintenance charts manual includes drawings? This is also a useful site
http://www.rm1872.org.uk/Brakes.html

My bus number (if any): RTL 960, RM 1585, RMC 1458 and several RTs

Re: Brake line test points

They vary, some of the earlier RMs had different threads to later ones, I've come across a couple like that. I can't tell you what the smaller threads are except that the adaptors on my test gauges don't fit them!

My bus number (if any): RML2532

Re: Brake line test points

The best solution is to remove the test point connector and take it to an hydraulic hose and fittings company. The smaller one which is an odd thread they should be able to supply in adapter form, this will have a built in nipple/flare. The larger one they can supply but without the built in nipple/flare, if you are lucky and get a supply of O rings then,depending on the condition of the fitting on the bus, it won't leak. The larger one is IIRC 7/16" UNF. A female 1/4" brake pipe union will fit, but you will need to use a male flare in the union and probably keep renewing the adapter pipe you fabricate.

NB. IT WOULD BE EXTREMELY FOOLHARDY AND DANGEROUS TO USE EITHER OF THESE METHODS TO CONNECT PERMANENTLY FITTED GAUGES IN THE CAB. It is advisable to bleed the brakes after connecting to the test points.

Re: Brake line test points

Thanks every one. I think its the larger one Roy & got sorted now.
Only wanted it to connect to a test gauge.
Thanks again. Brian.

My bus number (if any): RML 2616

Re: Brake line test points

roy
NB. IT WOULD BE EXTREMELY FOOLHARDY AND DANGEROUS TO USE EITHER OF THESE METHODS TO CONNECT PERMANENTLY FITTED GAUGES IN THE CAB.


Hello roy

Can you say why this is the case and are you only referring to the front test points or any of the brakie system test points?

My bus number (if any): M1001 RML2276 T806

Re: Brake line test points

The test points at all locations use what are effectively bleed nipples which have to be slackened in order for a pressure gauge to register a reading. To rely on an unlocked thread under considerable hydraulic pressure to prevent total loss of braking is stupid.

I do know that there is a low pressure warning system fitted, however I have been a passenger (for a very short while), during one of these popular running days when the driver thought it was a good idea to have pulled the blind behind his head down to prevent passengers seeing the dropped flag and illuminated warning light. He forgot the small square opening in the top corner.

Any idiot can read what is posted in this forum based on a Google search for an answer to his query. I know that there was some discussion about cab gauges some years ago. The two threads may possibly come up together leading to an idea of how to connect them in a dangerous manner.

Re: Brake line test points

Thanks roy. I thought that might be the issue. I wonder if these can be replaced with a permanent connection as there only use is for gauge connection. I had thought of cab gauges in the past but now I am looking at transducers. These would need to be permanent.
The accumulator points should be fine for a permanent connection although some mechanical protection may be beneficial.

Just had a search for gauge on here. Most posts are about fuel gauges with only your two post mentioning cab gauges.

My bus number (if any): M1001 RML2276 T806

Re: Brake line test points

I don't see any reason why this can't be done from the accumulator test point blocks, since air and vacuum systems both have cab gauges. It just needs a properly engineered installation which takes account of clipping, chafing, vibration and relative movement between cab and A frame.