R8 Alpine clutch shudder

Probably not relating to the clutch shudder but you do have the later bellhousing /engine side braces I assume. ?
The car currently has the old style 330 bellhousing. I have one of the later style housing which I hope to install soon. I'm not familiar with side braces.
Bob
 
I suggest that you find some side braces and put them on. Renault didn't spend the money putting them on all R8/10's unless they were necessary.
 
Bob!! Where do you get this notion that the "Extra Weight" is causing the problem ???
Have you weighed the different motors ??
I build Early Alpine A110's (light weight) wit 807 motors and Big 5 speed boxes and never had clutch shudder. I take the 688 motors out of the same cars and fit R5A/G motors with Big 5 speeds, and don't get clutch shudder.

You need to change your mind-set to overcome your problem. To me clutch shudder is contamination or bad surfaces in the clutch application area. Or badly matched clutch components.

A friend of mine was a drag race champion in multiple classes. One weekend he had bad clutch slip and couldn't work it out, and to clean the area he poured CocaCola into the bell housing, dried it out with a test run, and had no more slip for the weekend !!!

Ray
 
I suggest that you find some side braces and put them on. Renault didn't spend the money putting them on all R8/10's unless they were necessary.
I don't understand what you mean by side braces. Do you mean the rubber mounts that connect between the chassis cross member and the gearbox? I have those. In fact I recently installed stiffer ones from Mecaparts that were designed for competition rally cars. Sorry for the confusion on my part.
Bob
 
Bob!! Where do you get this notion that the "Extra Weight" is causing the problem ???
Have you weighed the different motors ??
I build Early Alpine A110's (light weight) wit 807 motors and Big 5 speed boxes and never had clutch shudder. I take the 688 motors out of the same cars and fit R5A/G motors with Big 5 speeds, and don't get clutch shudder.

You need to change your mind-set to overcome your problem. To me clutch shudder is contamination or bad surfaces in the clutch application area. Or badly matched clutch components.

A friend of mine was a drag race champion in multiple classes. One weekend he had bad clutch slip and couldn't work it out, and to clean the area he poured CocaCola into the bell housing, dried it out with a test run, and had no more slip for the weekend !!!

Ray
I may have over-estimated the weight of the R5 Alpine motor. I have been concentrating on the shaking (vibration) caused by the clutch shudder. I spent my career as a vibration engineer so of course I want to suppress vibration which is all about mass, stiffness and damping. It's the cause of the clutch shudder itself that I wasn't concentrating on. But Frans, Jaahn and others have set me straight on the likely cause--a lack of slack in the clutch cable. I have a new cable on order (the old one was bad), and I'm confident that will solve the problem.
Bob
 
I don't understand what you mean by side braces. Do you mean the rubber mounts that connect between the chassis cross member and the gearbox? I have those. In fact I recently installed stiffer ones from Mecaparts that were designed for competition rally cars. Sorry for the confusion on my part.
Bob
These as indicated by the arrow.
My experience with the R5 motor is that you may need to slightly modify depending on the set you have.
37B08388-5E88-429E-9F71-CAC853D4BA37.jpeg
 
With regard to the side braces, since the late 60's, I have been driving R10, 1100 and 1300cc (modified motors) and wider rims and tyres without the fitment of the side braces without any problems. My current R10 is without side braces; no problems! I also never fit the "deflector plates" on either side of the engine, no problem!

Henry
 
I guess my question is.... why did Renault go to the cost and trouble of fitting these things if they weren't required? If they were trying to be price competitive why spend the extra money? It is a bit like removing the brake balance valve from the rear. I have a mate (a mechanical engineer) that has spent most of his career driving prototype Jaguars and Landrovers around Europe and various race tracks and recommending changes to improve the vehicle prior to production. He is currently fitting a rear brake balance valve to his standard Nissan Skyline to improve braking performance some thing he claims should have been fitted in the first place. Vehicle manufacturers do not spend money on vehicles if it is not necessary.
 
That is very true, but keep in mind the R10/8/etc have been designed in the fifties. It is very likely the margin of error was quite high back then so one way to make sure the whole shebang didn't come apart was to overengineer it a bit more than would be needed today.

As for saving money, I have driven a Toyota Yaris for a year in Europe and to my surprise it handled quite well even though to my (even bigger) surprise it didn't have anti-roll bars. And no, the owner didn't remove them. I found a lot of info on Toyota forums and it seems only some had a front anti roll bar. Can't tell you what models and what the differences were/are but I would assume minimal so it can't be that. It was simply a money saving choice of the manufacturer. Most likely bottom line models didn't have them, more upmarket (Yaris!) did. The one I drove was a total poverty pack.
 
With regard to the side braces, since the late 60's, I have been driving R10, 1100 and 1300cc (modified motors) and wider rims and tyres without the fitment of the side braces without any problems. My current R10 is without side braces; no problems! I also never fit the "deflector plates" on either side of the engine, no problem! Henry


:rolleyes: Hmmm who should i back here. Henry with years of ignoring the excess parts that are not necessary or the engineers that designed the cars ??
Hmmm, gees a hard choice here🥴

Those deflector plates in the engine bay are part of a clever planned air flow through the radiator. In the top at the rear of the engine lid and foward through the radiator then back out the bottom of the engine bay into the low pressure area encouraged by the deflector plates. :mad:Who needs 'em.
Jaahn
 
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I may have over-estimated the weight of the R5 Alpine motor. I have been concentrating on the shaking (vibration) caused by the clutch shudder. I spent my career as a vibration engineer so of course I want to suppress vibration which is all about mass, stiffness and damping. It's the cause of the clutch shudder itself that I wasn't concentrating on. But Frans, Jaahn and others have set me straight on the likely cause--a lack of slack in the clutch cable. I have a new cable on order (the old one was bad), and I'm confident that will solve the problem.
Bob
hi bobG one thing I thought of,which I presume you have done, is clutch spigot bush in end of crankshaft replacement.i had come across a few bushes that had worn/cracked longitudally over the years. if bush has been replaced was it pretty lubed in engine oil as they are porous and need, to be lubed. if you put finger over one end of bush fill bush with engine oil then press finger over other end you will see oil ooze out of sides of bush.i would still put a small amount of grease on end of clutch shaft. other thing is input shaft protrusion to allow good support in spigot bush. just another thought.... jim
 
Jaahn,
I am with Henry on the defector plates. They were designed for European winters, splashing salted snow and water up into the engine bay.

As for engine stays/braces, they were designed for rough terrain roads to stop bell housing cracks. In Rhodesia we had R8 and R10 cars on very rough roads, and if the supports came loose, we would have to replace bell housings as they would be severely cracked. Remember these cars were developed in North Africa, on "Dakar Roads". Right up tp R18/20/25.
 
:rolleyes: Hmmm who should i back here. Henry with years of ignoring the excess parts that are not necessary or the engineers that designed the cars ??
Hmmm, gees a hard choice here🥴

Those deflector plates in the engine bay are part of a clever planned air flow through the radiator. In the top at the rear of the engine lid and foward through the radiator then back out the bottom of the engine bay into the low pressure area encouraged by the deflector plates. :mad:Who needs 'em.
Jaahn
totally agree Jaahn,without deflector plates air from under car is fighting against fan blades trying to pull air forward to be drawn out of rear aperture of side panels which has low pressure area at rear of it created by air coming past it from under car thus assisting fan blades when panels are fitted.this was a common cause of r8/10 overheating faults I found when I had my workshop was side deflector panels removed........ just a thought.... jim
 
Jaahn,
I am with Henry on the defector plates. They were designed for European winters, splashing salted snow and water up into the engine bay.

As for engine stays/braces, they were designed for rough terrain roads to stop bell housing cracks. In Rhodesia we had R8 and R10 cars on very rough roads, and if the supports came loose, we would have to replace bell housings as they would be severely cracked. Remember these cars were developed in North Africa, on "Dakar Roads". Right up tp R18/20/25.
My aftermarket shop manual doesn't mention engine/gearbox braces. Maybe the weren't used in the US market.
Bob
 
Always interesting on here.....

For what it is worth, here's a poor photo of a bog standard R8 clutch cable in place with normal droop. It's been like this forever and has no clutch shudder. My gearbox isn't as amazingly clean as BobG's but it has not been out of the car for at least 35-40 years and 200,000 km. :)

Another answer for BobG - the cable outer is not secured at the gearbox end, it just pulls out of the adjuster assembly. It's held in by the greater length of the outer relative to the distance from the fixed mounting point at the front and of course by the inner cable being secured to the clutch fork. So the engine/gearbox assembly can certainly move quite a bit on the rubber mounts without changing the clutch cable adjustment and, therefore, without causing shudder (not that there is not necessarily another contributing factor like the clutch itself). The easiest thing to play with is that cable droop with a spacer arrangement where it goes into the adjuster (which will then need adjusting of course). I have 2-3 mm free play.

I certainly make sure the two steel strengthening braces are in place and tight. Over-engineered for freeways perhaps but they were designed and built when many people drove on bad roads. There are several different geometries for the different engine versions. Heaven knows why as they are all Sierra engines, but the block mounting points changed over time.

I make sure all the cooling stuff is in place, and the car certainly is prone to over-cooling! Very efficient system and patented by Renault I think. I've never run it any other way but some obviously don't have problems without all the trays in place. Mine does get driven on 40-degree days sometimes.... It never overheats.
 

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My aftermarket shop manual doesn't mention engine/gearbox braces. Maybe the weren't used in the US market.
Bob
I doubt it. If anything, bits to make the cars more robust were more likely to be fitted for export markets, called "poor road" or "rough road" fittings. They are in all the factory parts manuals. The factory manuals are common on ebay and well worth getting, if only for the wonderful engineering drawings.
 
No the side bracing was used for all markets. The early R8 1130 had a Dauphine style gearbox but on the front was balance/vibration dampers (not sure which) of 2 cast iron blocks mounted on a rubber pad and hanging over each side of the gearbox. When the 330 gear box was fitted the side brackets and a metal cross piece were added. The vibration damper removed. 689-01 956cc engines 1 to 253,000 and 689-03 for the Floride S 1 to 1330 had no side brackets and the early gearbox vibration damper. After that the 330 gearbox was fitted as was the side brackets and cross piece. I would always fit them. Anyhow why not they don't intrude or cause any issue.
 
No the side bracing was used for all markets. The early R8 1130 had a Dauphine style gearbox but on the front was balance/vibration dampers (not sure which) of 2 cast iron blocks mounted on a rubber pad and hanging over each side of the gearbox. When the 330 gear box was fitted the side brackets and a metal cross piece were added. 689-01 956cc engines 1 to 253,000 and 689-03 for the Floride S 1 to 1330 had no side brackets and the early gearbox vibration damper. After that the 330 gearbox was fitted as was the side brackets and cross piece. I would always fit them. Anyhow why not they don't intrude or cause any issue.
Agreed - I neglected to say I thought the home market had the side bracing too. Ours is an R1130, but not a very early one, and I remember those cast iron damper blocks on the 318 gearbox (which failed mechanically). It also had those side bracing brackets from engine to bellhousing, but they were slightly different in geometry where they attached to the 956 block.

Yes, why would you NOT fit them? I've finally found a very late-type set that would secure my R10 1300 engine (an 810 series block) if I were to fit it, as they are different again!
 
totally agree Jaahn,without deflector plates air from under car is fighting against fan blades trying to pull air forward to be drawn out of rear aperture of side panels which has low pressure area at rear of it created by air coming past it from under car thus assisting fan blades when panels are fitted.this was a common cause of r8/10 overheating faults I found when I had my workshop was side deflector panels removed........ just a thought.... jim
I’ve run an R10 with hotted up 1.4 for many years, also with no clutch shudder or overheating issues. I ran the side braces, but not the deflector panels. Yes I agree why the panels are there, just that on my car with a good condition radiator and a VDO electric gauge I never ran more than 80C on the coldest or hottest of days in Sydney. The only thing I did do, was ensure the boot lid and radiator panel seal to the bootlid were present and in good condition (used aftermarket stuff).
 
I’ve run an R10 with hotted up 1.4 for many years, also with no clutch shudder or overheating issues. I ran the side braces, but not the deflector panels. Yes I agree why the panels are there, just that on my car with a good condition radiator and a VDO electric gauge I never ran more than 80C on the coldest or hottest of days in Sydney. The only thing I did do, was ensure the boot lid and radiator panel seal to the bootlid were present and in good condition (used aftermarket stuff).
It just might be that there's an extended low pressure area under that rear part of the car. If there were really big turbulence, I can't see the car cooling properly without the engine trays, but quite a few people say they do from personal experience. I suspect those top seals around the lid are key to this working. Interesting.
 
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