Blue Beauty from Malaysia

[simonc]

Thanks vanzep for that shot. Now I know what you mean! Thanks also to bb1 for asking the questions i would have asked as well.
Ta guys.

[nick_s]

Tidy motor @simonc

[simonc]

Just a quick update gentlemen as for the last week I’ve been fretting like a little girl about one, the fuel consumption and two, the high idle speed after all the work that’s been one on the Prelude.
The consumption has frankly been scary, filling the tank and watching those bars disappear, especially when I’m pootling around town or just popping to my office. OK, I haven’t been able to take her out for a good long yet and I know the motorway would return a better overall figure but blimey, even by Malaysian costs for fuel, it’s been costing a bloody fortune.
The second thing as I mentioned was an idle speed that was just too high. Now you guys know my (ahem) rather limited technical abilities and overall knowledge but I do know that 1000rpm ain’t right.
Anyway, I was chatting to my brother who has had a fair share of classics over the years, even rebuilding a Sunbeam Tiger more or less from the ground-up, and he suggested before getting myself wound up even more, or worse, spending more money on more bits, I should get the thing onto a Dyno and see if there’s faults there that are fixable or not.
So yesterday I went over to perhaps one of the best local shops that provide Dyno services to get it looked at. It was done all very professionally and I must admit, having never seen a car on a Dyno, was pretty interesting.
It was bloody amazing to see it flat out as the whole car seemed to ‘rise’ and almost be floating on the roller thing.
@Donald, you’ve got your finger on the pulse of things physics, why does it appear to float my good man?
(Actually, I forgot to mention that the first thing they did was a compression test in case the rings were not sealing properly. That checked out fine so that’s when the tester got strapped in and cranked it up to 11!)
He found the problem was the amount of fuel being put into the engine so that was adjusted as well as doing some faffing about with the distributor. Not quite sure what they did but there was some light and methodical spannerage going on there.
After about an hour I got a clean bill of health with a reduced idle speed which made everything so much smoother and apparently, he’d slowed down the fuel flow to make sure the consumption would be as expected from now on.
Aha you think, job done and simonc can return home. But no, hold your horses gents, the curse of the Blue Beauty strikes again. As I’m about to drive off out of the workshop, all smiles and chuffed to bits I felt a most alarming problem rear its ugly head. I engage drive (foot on brake) and the bloody thing drives itself forward as though I wasn’t even on the brake. With much more pressure on the brake it stopped but I immediately jumped out and asked them to try it in case I was doing something stupid. They agreed and backed her into the bay, opened the bonnet and diagnosed the brake booster was kaput. S**t!
So a call to a chop-shop got a brake booster sourced whilst I sat around twiddling my thumbs and smoking myself to an early grave in a state of high tension.
More spannerage once the thing arrived only for me to drive off a second time with my second weird sensation of the day. I pulled away but felt like I’d left the handbrake on or something. So once again, I turned around and headed back in to the amazement of the mechanics.
Sorry this is long-winded but what had happened was that the driver’s side piston had seized and obviously that’s what I was feeling. More spannering, cleaned the entire calliper and piston but then found the bloody master cylinder was not the right one for the booster they’d fitted. Double S**t!
It’s now coming up to 8pm, I’ve no transport and am presented with a fait accompli of the car remaining there as I’ve no bloody brakes. Arggghhhh, when will I ever go into a garage, get one thing done without having another problem arise?
Well, it’s Tuesday morning here and I’m in a state of high anxiety hoping they can get a master cylinder to fit. My last client leaves at 7pm so then I’ve got to get la Ng to run me over to the workshop before lights out at 8pm.
Apologies for this diatribe but just thought I’d share the tribulations (and the short lived Dyno joy) with you guys.
I promise a quick edit tomorrow with some hopefully good news.
Here's some photos to relieve the tedium of my story.

More strapping than at a Max Mosely private party.


Ready to rock and roll


All plugged in


Fingers crossed this won't be bad news. Just prior to blast off.

[Ted]

Well heres my diagnosis. High idle was from the engine sucking in air from the brake booster and then your brake sticking on was from the rod being either too long or not seated correctly inside the booster when fitted.

[simonc]

Morning Ted, you're right on the money with the rod being too long but I'm afraid I can't confirm your thought on the air thing. Thanks for your feedback. Just hope it's all going to be ready this evening.

[Donald]

It was bloody amazing to see it flat out as the whole car seemed to ‘rise’ and almost be floating on the roller thing.
@Donald, you’ve got your finger on the pulse of things physics, why does it appear to float my good man?

If I've understood you right and what you're seeing is the car appearing to rise as the wheels remain where they are, I imagine is something to do with shaft/suspension angles changing under load or something.

If you imagine where the drive is put into the shaft and where it 'terminates' if you like, i.e. the wheels, then I think the centres of these points would want to be as in line as possible to maintain efficiency (if you imagine a line drawn from the centre of each point to the ground, these centres would want to align. Since there is no downforce on the car keeping it in check, these forces I imagine will have an effect on the surrounding suspension components when try to achieve this. Nature likes the most efficient route (off-topic but this thinking is expanded in that program about bubbles currently on BBC iPlayer, well worth a watch).

Total guess though I'm afraid, poorly explained and I can't really help with the real problem here

[simonc]

Hi Donald, yes that's it. It rose and kind of straightened up. Thanks for the reply. It looked really strange ( but great if you know what I mean) bordering on surreal. I've never seen it before so my next question is does the car do that when we're belting down the road or does the air "push" it down?
Edit: Apologies - re-read your post in detail and see your point about the air pushing us down. Got it.

[Donald]

It is just a guess though, there are some proper physics boffs on here I think that could give a better explanation.

In a 'real' situation you can see it when you nail it vs ease the power on. If you foot down in a low downforce situation, like pulling off, you feel the front lift, whereas in a higher down force situation like motorway cruising if you do the same it is less exaggerated. I think when the 'load' if you like, exceeds the downforce (if you can imagine them in comparable/relative units) you get the lifting situation. Whereas if you lightly accelarate and the rate at which the load increases matches the rate at which downforce increases, you don't get it.

Anyway as said before, all a guess and I'm sure it's painful for someone that knows the proper terminology to read

[vanzep]

sound like they adjusted the distributor timing using a timing gun (that would have been the stobe light you saw being used)
the lude has two sizes of brake master cylinder. There is the 15/16" piston and the 1" . I have 15/16" mc as i have a non abs BB4. Not entirely sure what mc you will have but could be 15/16 as you have no abs. Easy way to check is to look at the side of the mc where the size is stamped onto the body.
Honda part number for 15/16" mc is 46100-SM4-033.
Here is a link to some further info:
http://www.ludegeneration.co.uk/honda-p ... t7097.html
And this link gives you all the info about brake booster and master cylinder including pushrod adjustment
http://www.tegger.com/hondafaq/mastercy ... tment.html

[wurlycorner]

Sorry to hear you've had some more bad luck.
Single roller dyno though = scary!