YHO chronicles

[Rambo]

1. didn't get the emissions sheet; the tester said since it was before 1995, they don't give them out as a rule - I didn't argue since he just passed it

Really. I've had 2 in the last month alone.

The one I got on Friday was really good - CO = 0.177%, HC = 148 ppm

[maz_r]

Yeah - I though it was weird too. I got one last year and perhaps he just couldn't be bothered. I would be interested in the numbers as I still haven't got to the bottom of the rough running.

Ho hum. At least it got the 'pass' and that's the main thing

[maz_r]

So it is (mostly) my own fault for not having the opportunity to turn over the car in a pretty long time. Alternator seized solid which resulted in an interesting set of smoke signals from the (ex-)belt. Couldn't get anywhere near it to try and free it off, so cut off the belt and drove the mile to my friendly mechanics. 2 days later, YHO now has a shiny new alternator, alternator belt and PAS belt to boot. Great service (they told me it was (and I quote) 'a bit of a bugger' to fit) but refused to charge me more than 2 hours labour. Still cost £370 mind....

[HJ2]

I'd say that's rather cheap!

[maz_r]

Oh dear - here we go again....

MOT failed with a whole heap of things which I was assured contained nothing major; mostly brakes related which I put down to the car not being used for a long time as well as an emissions fail. I wasn't too surprised about the emissions as I had been fiddling about to try and sort out the long-running 'over fuelling' (if that indeed is what it is).

So, emissions were sorted by a reset of the timing and CO pot twiddling - sailed through on the retest.

The brakes however.....

The mechanic took it for a long run to 'get them red-hot' and it just about squeezed through the MOT but he wasn't happy about it; he couldn't lock the wheels on the road and now we have gained an interesting metallic 'creak' when applying the brakes. He is concerned that in attempts to get the brakes to pass muster, he's buggered the master cylinder (one of the springs might have snapped?).

I am beginning to think that the car just has it in for me and my will is slowly crumbling; to cap it all I've been ill with different things for what seems like forever which means I can't work on the car myself and the costs of all the repairs are getting too much to sub out. This might be the last straw.

Oh; and just to add fuel to the fire, the new alternator isn't charging the battery, so that needs to be sorted out yet again.

If I were given to such things, I could swear

[maz_r]

Addendum:

Just been and stamped on the brakes (while stationary on the drive) and the creaking noise seems to be coming more from the front calipers than anywhere else. Does anyone with experience of HiSpecs fronts know if they can/are prone to seize; I guess the fun and games might be because only one side of the caliper is moving? Or is that codswallop? The balance was OK on the MOT so they'd both have to be seized the same which feels unlikely. Is there a refurbishment kit for HiSpecs?

[muley]

Martin

So sorry to hear of your challenges with Blacky.

TBH I never thought the HiSpecs were much better than standard, possibly because I went for the 15" kit (smaller discs). I was disappointed, too, with the PNM rear kit ~ didn't really improve much.

If the master cylinder is faulty ~ it may have been a cause of the poor braking all along..

Hopefully she can be brought back to life for not much more effort or expense; and your health improves.

Jim

[lotusflasherman]

Addendum:

Just been and stamped on the brakes (while stationary on the drive) and the creaking noise seems to be coming more from the front calipers than anywhere else. Does anyone with experience of HiSpecs fronts know if they can/are prone to seize; I guess the fun and games might be because only one side of the caliper is moving? Or is that codswallop? The balance was OK on the MOT so they'd both have to be seized the same which feels unlikely. Is there a refurbishment kit for HiSpecs?

Codswallop... and your earlier post made me laugh - "nothing major; mostly brakes related " .

HiSpec conversion is usually Billet 4 caliper - 4 pistons, 2 each side on a fixed caliper. If the caliper is moving something is very wrong! Pads slide along pins so you might be hearing that - or check the friction material isn't coming of the backplate. Not on Greenstuff are you? Early ones were useless until they were warmed up and can be prone to coming off the backplate according to a Dutch friend...

Mine work perfectly but I use mine on a regular basis all year round... regular exercise for cars is just as important as for people...

By the way, your mechanic is an idiot - the pressure limiting valve is there to stop the rear wheels locking and it's difficult to lock front wheels on a fwd as you will trying to stall the engine... perhaps he should use a Tapley Brake Meter.
The return springs in the master cylinder are doing nothing when you stomp on the brakes - it's the seals that are working hard. When you come off the springs do a bit of work to return the seals to their 'no pressure position'. How far they are compressed just depends on the pedal position, not how hard it's being pressed. Only times the springs are fully compressed will be if you loose one circuit or are bleeding the brakes... and they are designed for that. (Not to say they can't fatigue through age though...)

[maz_r]

Thanks both.

Obviously, I meant pads/pistons not calipers before. Spoke to PNM and they say they've not had a case reported of the pistons seizing (but they did also say 'never say never').

Car is back at the garage having the alternator looked at and also they are going to strip the whole braking system down and get to the bottom of it.

I may have been slightly over-critical earlier in my grumpiness; the mechanic absolutely knows what he is doing - he rebuilds Jaguar E-Types (amongst many others) from the ground up; last time I was in there he had a Bristol half-rebuilt and it looked fab, so lets say that together we will sort it out (although it may start getting pricey).

Interesting to hear you say that you were never that impressed with the HiSpecs Jim. When I put them on the red car, it was like night and day (to me, imho, please lets not start another 'standard set up is fine' conversation!). And they were pretty good last year when the pads got swapped over to EBC standard road pads as recommended by PNM. Something has changed since then...

And with regard to your comment about cars needing exercise like people Phil, I'm not sure 3 minutes of exercise every 6 months is what you had in mind....

[maz_r]

Good news and weird news...

Good news first: alternator fixed and charging like a good'un - phew. Apparently the cable wasn't seated properly and the garage were tremendously apologetic.

Weird news: the brake excitement continues. So upon investigation the garage are saying that as the brake pedal is operated, both sets of pistons start to operate and push the pads onto the disk - nothing odd there. Then, as more pressure is applied, the inside pistons push the pad onto the disk and that in turn pushes the outboard pistons back into the caliper. Therefore we are getting, as I suspected, effective braking on one side of the disc; the garage are completely mystified. And before you say it, yes, they bled them repeatedly (sucking, blowing, upside-down (insert other slightly dubious innuendo here)) and it has made no difference. Even more bizarrely, it is happening on both front calipers. It makes no logical sense since the pressure inside the caliper ought to be consistent so nothing should have more force behind it than anything else. The creaking noise previously reported is the sound of the caliper pushing itself out of true as one side pushes against the disc and the other side doesn't. They also suspect that since the pressure in the system never really 'peaks', the rear limitiers are coming into play and thus the MOT rear braking effort fail (makes sense to my simple brain).

So, weird or what. I feel a phone call to PNM coming on......

(and the worst news is the garage won't give me the car back and it is glorious weather )

[Brit-Car-Nut]

What is the chance the weird side brake hose is "ballooning" or otherwise failing under the heavier pressure?

[muley]

What is the chance the weird side brake hose is "ballooning" or otherwise failing under the heavier pressure?

Good question. IIRC I put braided hoses on the car..


Jim

[maz_r]

Hi John,

Yep; braided hoses fitted (and they checked for any issues with the hoses). And also, maybe I didn't explain correctly; when I say each side, I mean each side of ONE caliper. And both front calipers are doing exactly the same; it is apparently doing it's best to bend the disc (I know discs don't bend).

[Brit-Car-Nut]

I had several braided brake hoses with a Teflon core go bad but that caused no fluid passage and finally leaks.

Sounds like a tear down and rebuild. Possibly the "O" ring seal between the halves has gone bad and under pressure is flattening and covering the thru hole.

Due to the fact that heavy braking is trying to bend the disc, I would assume for a moment that the BMCyl is working OK.

[lotusflasherman]

Sounds like the port in the upper spacer is blocked for some reason. Look at the picture I sent earlier...The spacers are the blue bits shown between the pads and only the upper one, on the left, has a port through it and is sealed to caliper parts with a couple of 'O' rings. Spacers are interchangeable for various disc thicknesses and it's all simple stuff...(I presume nobody has pulled the calipers apart and put the spacers in reversed have they ???? )

Suggest garage opens the outer bleed nipple and sees if any pressure can still be created to operate the inner piston.. If so the port is blocked or in the wrong place.... solution is split the caliper and check ports and 'O' rings...

[maz_r]

At last, we have brakes! Jolly useful, those, i have found....

Garage split the existing calipers and couldn't find anything amiss - O seals were fine and the channels were clear but still when reassembled, they were behaving the same. In desperation (and a triumph of wallet over any mechanical nouse) I bought a whole new kit from PNM. It is fitted and working just like it ought to. The garage are absolutely mystified as to why but very relieved that the new kit did the trick

The old calipers are going back to PNM for them to investigate so hopefully they can be refurbished/engineered and then I can sell them on as a working kit; hopefully that will lessen the financial blow. I couldn't in all consciousness sell them as they are....

[lotusflasherman]

At last, we have brakes! Jolly useful, those, i have found....

Garage split the existing calipers and couldn't find anything amiss - O seals were fine and the channels were clear but still when reassembled, they were behaving the same. In desperation (and a triumph of wallet over any mechanical nouse) I bought a whole new kit from PNM. It is fitted and working just like it ought to. The garage are absolutely mystified as to why but very relieved that the new kit did the trick

The old calipers are going back to PNM for them to investigate so hopefully they can be refurbished/engineered and then I can sell them on as a working kit; hopefully that will lessen the financial blow. I couldn't in all consciousness sell them as they are....

I'd have bought them as they are, if the price was right and they are Billet 4... would have liked to see what this mystifying problem is and have an SE on SORN, still on OE brakes, and spare seals and spacers for Billet 4's...

What are PNM charging for a refurb' ?

[maz_r]

New battery and she fired up first turn. Everything I tried worked, so off the drive for a pootle up the road. Still all working amazingly. Give the brakes a gentle then not so gentle test - still all working, which was a blessed relief after last years debacle! Up the main road for a bit of a whizz. Sweet.
Waved at an Elise, got burned off by a Porsche GT4 (I think), passed an E Type going the other way.
Forgotten how much fun this is!
Next up, MOT time....

[maz_r]

Now with a shiny new MOT

[muley]

Excellent. I have a wheel here should you need it. Not satin black tho"


rgds


Jim