Weak Braking After New Servo Installation

[neil1800]

I switched the brake lines around last night, bled the lines again, and the brakes seem pretty solid now, based on a quick driveway test. Great!
There is a non return fitted between the servo and the hose. The instruction manual says "an inline non-return valve is advisable on high performance vehicles." Not sure if I qualify on this count.

I've attached some photos of how I installed the unit (needs a little TLC still). I installed it tilted upwards, per the instructions. And the hose fits straight onto a pipe mated to the manifold - Derek, not sure if that's what you describe as the side ear?

I guess the other point I'd ask here is if anyone has experience of what the longevity of these units are? My previous unit, a Girling, possibly stock, gave out with little warning. Or at least I was unaware of any longer term tell-tale signs (white exhaust, for example.) I'm grateful to have lived to tell the tale but I'd rather not repeat that experience. I've read similar stories on some archived threads on here.
Anyone know if the Lockheed type fail in the same abrupt manner?

[123GT-AMAZON]

we normally fit them a little higher up than you have yours mounted but being a remote servo should work anywhere aslong as its setup correctly do you get any engine knock ? just wondering if the engine could say on a bad tickover state jerk and knock on to each other ? just a thought but all looks great apart from that.
great news that you have a more solid pedal now

kind regards
robert

[Derek UK]

=1 on Robert's comment about the positioning. Slightly soft engine mounts and bumpy roads might have you damaging the plastic filter housing. Keep out of central NY! As I said it's difficult to fit this servo neatly, a situation made worse by you having a LHD 1800. You've kept the original box mount. I know this is used for the choke cables and maybe the washer pump and bottle, can't see if they are still there on your picture. That does get in the way but I'd have been tempted to remove it and start over.
The side ear is the one on the engine block on the servo side. You have the pipe with the PCV valve correctly positioned and it then routes over to the early alloy manifold. This pipe is the one that can be used with a T piece to provide vacuum to the manifold on cars with the iron manifold that doesn't have the front fitting for the servo pipe.
Once you're happy that it all works well you might consider re engineering the mounting to give better access to the fuel pump, steering box etc. Might mean a couple of new brake pipes and re siting the washer bottle and pump. A later bottle with top pump works well, depends on how close you want to keep it to stock.
Servo failure should just give you heavy brakes. A bit of a shock when it happens suddenly but you should still have full braking. IF this servo is a genuine one, longevity should be good but if you've searched around for a cheap deal you may have one of the more unpredictable Chinese clones.

[redcar]

gents, sorry to come in on this thread, but i am about to attempt the same things myself... bombing along at 80 with a unassisted single circuit system scares me sometimes.

i plan on getting the servo unit from here.. is this the one you fitted, or should i be looking elsewhere? also, did you change your rear wheel cylinder to a 7/8 bore from 1 inch?

any guidance greatly appreciated..
thanks,
gareth

[swedishandgerman]

That isn't a genuine Lockheed but if you go on the basis of the fact it is half the price of Brookhouse

Please bear in mind that fitting a servo does not improve braking performance, so whatever the circumstance, you should most definitely check the whole brake system: callipers, rare brake adjustment and as I just found, hand brake cables

Servo just reduces how much force you have to put on the brake pedal. If you're unsure of brake performance, you should investigate

FYI I've just done this job, so have a look on the Wlliam the Estate thread

[Bladerider]

Originally Posted by redcar

gents, sorry to come in on this thread, but i am about to attempt the same things myself... bombing along at 80 with a unassisted single circuit system scares me sometimes.

i plan on getting the servo unit from here.. is this the one you fitted, or should i be looking elsewhere? also, did you change your rear wheel cylinder to a 7/8 bore from 1 inch?

any guidance greatly appreciated..
thanks,
gareth

I changed the rear cylinders on the advice of Tony Barrett to prevent lock up.