ScottR400D

25 minutes ago, AlastairA said:

Apologies for my lack of clarity - it was the following that I was referring to and I was just suggesting to the OP that it might be worth checking it is fitted:

 

• ChrisC
• Member
• • 2.3k

 

Posted November 30, 2021

I have it in writing from CC, it was added for clearance between the chassis and the gearbox.  If you think that statement through, that means clearance is marginal without it, something that's been known for some time.  Given the price and how easy it is to fit, for me it's a no brainier, on any pre 2021 5 speed Mazda boxed car, especially if your working on the car in that area.

That said, the reason it dramatically reduced my cars noise wasn't because of clearance, it was because it altered the prop working angle slightly, which combined with a faulty front UJ meant a reduction in noise and vibration.  Ultimately my car was only fixed of vibration and unexplainable noises with a prop replacement.  
 

As Chris implies above - clearance between the chassis and gearbox is marginal without the spacer.

And as he says the clearance or lack of wasn’t the issue. 

55 minutes ago, AlastairA said:

I was thinking of ChrisC's comments here:

 

As Chris implies, alignment wasn’t the issue. His prop was failing. 
If you research the alignment issue you’ll see it needs to be far more out of line than  a 7 would ever be. 

32 minutes ago, AlastairA said:

There is a spacer used between the gearbox and the gearbox mount on currrent kits. My understanding is that the spacer was introduced to get better angular alignment from the gearbox output shaft to the differential. Might it be worth checking whether this is fitted?

There was/is a spacer that does something but not what you allude to. Not much can be done about engine/box alignment, the front of the engine needs to be down to clear the hood. 
In any case any angular misalignment is negligible. It’s a red herring.
 

Do we have any words of wisdom from HWM? 

16 minutes ago, Matt420R said:

Indeed. When you look at what the they are probably sourcing them for, I think there is considerable profiteering going on in this space. 

https://www.aliexpress.com/w/wholesale-5.75"-LED-Headlight-.html?spm=a2g0o.productlist.search.0

 

Par for the course for some. 

1 hour ago, GulfSeven said:

£23 each is insane! JAL and Sevens and Classics charge £380 for their top of the range ones*. £120-£180 for their cheaper ones. What's the catch?

* We'll ignore Caterham's prices (nearly twice the JAL price for the exact same unit).

Perhaps it’s not the £23 that’s ‘insane’?

9 minutes ago, prisoner7 said:

Scott - I did search for information about this before I posted this question. Unfortunately for me, I'm in the US and won't have access to CC's PBC. Thank you - all of you, for your inputs.

I wasn’t replying to you actually. I think all you need to know is that they’re not always well set up from the factory, CC will just make excuses but they can be fixed. I’m afraid in the USA you’ll have even less support than we get. The PBC wouldn’t help as shown above. 

If it gets set up properly by someone who knows what they’re doing and cares it will be fine. Just hoping it will get better doesn’t work. 

I'm not sure I’ve ever read so many posts going over things we’ve discussed so many times over so many years. 

You clearly haven’t spotted the elephant in the room yet…….

Not until the car’s set up properly often. Been like that for years.  My ‘15 car was like that till I had RBTBs fitted and mapping done. 

I think you’ll find the answer is yes.  Shouldn’t be like that but they very often are. 

2 hours ago, JAL73 said:

It’s going in to HWM tmrw and they are aware of the issue, will report back if they have any success in reseating it to avoid contact with the tunnel walls and checking the engine and diff incline angles. 

Surely Caterham have not engineered the width of the inside of the transmission tunnel to be less than or equal to the width of the widest section of the gearbox. I appreciate the tolerances maybe very fine but I’d hope it’s possible to seat the gearbox so that the only NVH transfer point to the chassis is via the gearbox mount. 

I’d love to hear what HWM have to say. 
 

Caterham didn’t change the chassis when the Mazda box began to be used. Just like when they changed the radiators, diffs and anything else. Engineered? 🤔
 

By the way, back in 2020 I asked one of CC’s ‘experts’ to confirm that the Duratec sloped forward to clear the hood. His answer? “I have no idea”  

As I asked, do you have a Titan LSD? Sintered plates? You’ll never enjoy low levels of NVH with that if so.

A final comment. The accumulated knowledge and experience in these pages will outweigh that of HWM by orders of magnitude. I would be wary of how much time I wasted.    

1 minute ago, Drakman said:

This is a good view of what happens with out of alignment tail shafts and velocity.

 

Yes that's in the ‘21 thread. 

24 minutes ago, JAL73 said:

Im about to go on a road trip hence my renewed focus on NVH...

I was talking to Ollie at R&R Transmission about NVH and he said that the relationship between incline of the engine and the incline of the diff can stress the UJs on the propshaft and cause NVH to be transmitted from the engine to the diff. That sounds plausible but no idea how to test whether my car suffers from that particular ailment. Vibrating elements touching the transmission tunnel also seem highly plausible but not sure if this can be avoided with Duratec/ Mazda applicaiton given the tunnel width.   

That’s yet more old news. The Duratec does cant down at the front to clear the hood. About 1.8 degrees. 
But the diffs also point downwards by a similar amount. As long as the output of the box and input of the diff are parallel there no problem. 

When we investigated this closely a few years ago the ‘out of parallel’ amount was negligible. 

What Ollie has told you isn’t true. But it’s a good excuse for the noisy as sin LSD. 
Search for a thread from ‘21, called PROP SHAFT ALIGNMENT AND VELOCITY

I’m assuming you guys have LSDs? If not then it’s probably as good as it gets. If you do then look no further.  

On 26/04/2024 at 08:59, Jonathan Kay said:

Yes, this was stated in the recent online meeting with, IIRC a date.

Jonathan

There was a post in here recently where a customer’s car was on stop because they had no engines. 
Caterham say a lot of stuff, it’s not always true. 
Time will tell. 

Any progress with these things?

The more I think about it the more I wonder if anything at all is being done re the Titan. CC seem to be having issues getting Duratecs and it seems possible that they won’t be available for too many years to come. Doesn’t seem worth developing a decent LSD now. 

That will leave just the little Japanese engined cars which hardly need an LSD in any case. 

17 minutes ago, paul richards said:

Unfortunately you can’t get caphead nuts. 

No s**t?

If you look at it a cap head allows the bolt to be run in, the nut doesn’t need to turn, you just hold it. Try that with a hex bolt and nut. 

Anyway, off you go……
 

As I recall, I had cap heads on that fitting, made it a lot easier to fit. 

7 hours ago, SteliosV said:

I have this too - putting it into first prior to engaging reverse helps, but if going back and forth between first and reverse (e.g. when manoeuvring) the clunking manifests itself again after around the third engagement of reverse.

What clunking? We’re talking about gear chatter and that shouldn’t change other than maybe a tiniest bit as it warms. 
If there's a clunk beginning it’ll be the diff warming up.  

27 minutes ago, Geoff Brown said:

Not 'normal' at all. My 11 year old six speed does nothing of the sort. Could be a slightly dragging clutch ? More noticeable when cold & selecting reverse.

Entirely normal with a non synchro box. Explain the mechanism the stops it.if it’s not if it wer a dragging clutch starting with clutch depressed would help but it does of course. 

It’s normal, not a gearbox issue and not a clutch problem. 
As said no synchro on reverse so the teeth will grind. Starting in the garage cold, depress the clutch then start it’ll engage cleanly because both shafts are stopped. Start in neutral, go into a forward gear, move,  then come out of gear and straight into reverse, griiiiind. 
Again as said in such a case go in and out of first while stopped then out of first into reverse. Contrary to what PP thought waiting a few seconds with clutch depressed then going into reverse does work. 

34 minutes ago, Ainsley said:

It was the Orange stuff and on the back it said "do not dilute", so its going in straight from the can.

I’d get some more, you’ll need it when the rad starts to leak………. 🥴

27 minutes ago, raw said:

@ScottR400D The leak on the radiator that has just been replaced did not appear to be stress related, I suspect it was a coolant corrosion issue as has been discussed many times before and swapping to blue coolant last year made the leak worse. Thanks for calling my solution a lash up but it works for my car and has done for around 10 years. I only offered it as an alternative.

Cheers

Andrew

 

I remain of my opinion. And there’s little evidence of any radiator being corroded by coolant. Radtec say don’t use the orange but I and many others have for many years with no issues at all. 

I’m still of the opinion that the main issue with CC rads is manufacturing quality.

As for the hose and bolt ‘solution’ they neither support the radiator nor protect it from vibration. I just don’t get why you would do that.   

41 minutes ago, AlastairA said:

My understanding is that the metalastic bobbins are there to absorb small amplitude vibrations, not large mechanical deformations. I don't have any direct evidence that jacking on one side causes radiator leaks, but when I did do it, the driver side wheel was several inches clear of the ground before the near-side even started to lift. Can't be good!

You're right. 

11 hours ago, David JLM said:

Not just me then... I used to wince when jacking my Academy car up via the tow loop.  It was the accepted method but it didn't feel right, watching the chassis twist. 

I'll be using the front cruciform with my new car!

It’s the only way. 

I think a race team is the only option. I’m not sure any sensible owner would buy a Titan assembly any more, let alone a used one that, despite what Ollie said, could go bang tomorrow. 
 

And I am the owner of a fully rebuilt complete differential assembly that I can’t sell, even to race teams! ☹️

 

4 hours ago, Jonathan Kay said:

Thanks

I'm trying to work out why Doc007''s doesn't...

Jonathan

I think it was too small, JK……….😜