The bell housing has 'inspection holes' in it to see that the clutch fork has engaged in the release bearing (attached to the diaphragm spring) and although this is useful in ascertaining that the forks have properly engaged it led to the fork shaft rusting and the whole mechanism had partially seized causing clutch slip. The pin, before modification, is just a plain affair, 7mm in diameter, and held by the spring in the picture. The original had seized and caused quite a problem to remove. The car owner is handy with a brazing torch and he welded the huge head on the new pin. Next time it can be tapped out with a wee drift.
Pull Clutch Mod
Moderator: RichardW
Pull Clutch Mod
After a fun afternoon removing a gearbox from a Xantia with a pull clutch the following modification was made to the pin that holds the release arm to the fork:
The bell housing has 'inspection holes' in it to see that the clutch fork has engaged in the release bearing (attached to the diaphragm spring) and although this is useful in ascertaining that the forks have properly engaged it led to the fork shaft rusting and the whole mechanism had partially seized causing clutch slip. The pin, before modification, is just a plain affair, 7mm in diameter, and held by the spring in the picture. The original had seized and caused quite a problem to remove. The car owner is handy with a brazing torch and he welded the huge head on the new pin. Next time it can be tapped out with a wee drift.
The bell housing has 'inspection holes' in it to see that the clutch fork has engaged in the release bearing (attached to the diaphragm spring) and although this is useful in ascertaining that the forks have properly engaged it led to the fork shaft rusting and the whole mechanism had partially seized causing clutch slip. The pin, before modification, is just a plain affair, 7mm in diameter, and held by the spring in the picture. The original had seized and caused quite a problem to remove. The car owner is handy with a brazing torch and he welded the huge head on the new pin. Next time it can be tapped out with a wee drift.
Some may be for ventilation but the one at the bottom doubles up as an inspection hole. If they are purely for ventilation then why put one at the bottom? A little knowledge of thermal flow would tell you that is not the place to vent. I doubt if the head will come off. It is down to proper brazing as in bicycle building. Anything else you would like to poo poo?
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Kowalski
- Posts: 2557
- Joined: 15 Oct 2003, 17:41
- Location: North East, United Kingdom
- My Cars: Ex 05 C5 2.0 HDI Exclusive 145k
Ex 97 Xantia 1.9TD SX 144k
Ex 94 Xantia Dimension 1.9TD 199k
No,
I think I poo-pooed everything that needed poo-pooing.
I've never had much luck with brazing, it is rather like soldering where if you don't get things hot enough the braze doesn't always wet the metal and doesn't stick properly, although with a small pin it is probably easy enough to get it hot enough. Welding with a mig is relatively easy compared to brazing or soldering.
I would agree that logic says hot air rising and all, that there should be another ventilation hole at the top of the clutch housing the clutch spins though, so I think the centrifugal effect on the air would disrupt the nice vertical convectional air flow, so its probably designed to take advantage of the air that the clutch moves.
The holes in the bottom of the bell housing are very convenient to let water in to the clutch but they're also convenient for letting it out again, the holes being at the bottom mean that anything that gets into the clutch housing can get out again rather than getting stuck and I suppose the holes at the top stop anything from being able to fall in. I've had stones trapped between my brake pads and my brake discs before, they're nuisance enough I wouldn't want the same to happen to my clutch.
I think I poo-pooed everything that needed poo-pooing.
I've never had much luck with brazing, it is rather like soldering where if you don't get things hot enough the braze doesn't always wet the metal and doesn't stick properly, although with a small pin it is probably easy enough to get it hot enough. Welding with a mig is relatively easy compared to brazing or soldering.
I would agree that logic says hot air rising and all, that there should be another ventilation hole at the top of the clutch housing the clutch spins though, so I think the centrifugal effect on the air would disrupt the nice vertical convectional air flow, so its probably designed to take advantage of the air that the clutch moves.
The holes in the bottom of the bell housing are very convenient to let water in to the clutch but they're also convenient for letting it out again, the holes being at the bottom mean that anything that gets into the clutch housing can get out again rather than getting stuck and I suppose the holes at the top stop anything from being able to fall in. I've had stones trapped between my brake pads and my brake discs before, they're nuisance enough I wouldn't want the same to happen to my clutch.
The opening at the bottom is I'm sure there to assist location of the release forks. There is a vent at the top and three at the side. The one at the bottom is much bigger and I was able to spin the bearing for proper orientation through the hole as the gearbox went in.The gearbox in my Peugeot has no hole in the bottom and I can't see that it would be less likely to overheat than a Xantia. The job was a lot easier than the supplier of the clutch and one or two others had said it would be. The problem was the seized components making removal of the gearbox difficult. Unless the release arm is off the forks can not clear the bearing. The pin was not absolutely seized but tight enough not to come out with vise grips or whatever else we through at it. It will, I'm sure, be no problem if it has to come out again. Whatever theories about draining of water, the shaft was rusted solid. It looked like whoever had the car (the present owner got it cheap because of the clutch) was taking it off road by the amount of grass/straw/mud lying in nooks and crannies around the subframe.
As for brazing v welding it really depends on what is to hand. If I had done it myself I would have turned it out of one piece of carbon steel and tempered it.
As for brazing v welding it really depends on what is to hand. If I had done it myself I would have turned it out of one piece of carbon steel and tempered it.
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by dan.2cv</i>
yes, thermal flow and all that; hot air rises out through the top holes, where's all the cold air? At the bottom? suck it in through there then.....
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
There is one small gap at the top not 'holes'.
The cold air would get in at the side or more rightly front. Air would get through the radiator. The bottom hole is serving a purpose. You need it to ensure the forks engage and the bearing is in the right position. Try it and see. Vent? Bo**locks. And if anyone would care to actually look at the way it is set up you will find that the bottom hole gets covered by a (naff) plastic guard (or oil collection tray as it ends up as being) so air flow would be restricted (but, alas, water can seep in). It is a clutch not brakes. If you use the clutch enough to get it that hot I would recommend an automatic.
Have any of these 'airflow experts' ever changed a clutch on one of these vehicles? If you have then how did you know the bearing was in the right position once you had the gearbox in place?
Anyway, that is the modification we made. Next clutch change I will be laughing.
yes, thermal flow and all that; hot air rises out through the top holes, where's all the cold air? At the bottom? suck it in through there then.....
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
There is one small gap at the top not 'holes'.
The cold air would get in at the side or more rightly front. Air would get through the radiator. The bottom hole is serving a purpose. You need it to ensure the forks engage and the bearing is in the right position. Try it and see. Vent? Bo**locks. And if anyone would care to actually look at the way it is set up you will find that the bottom hole gets covered by a (naff) plastic guard (or oil collection tray as it ends up as being) so air flow would be restricted (but, alas, water can seep in). It is a clutch not brakes. If you use the clutch enough to get it that hot I would recommend an automatic.
Have any of these 'airflow experts' ever changed a clutch on one of these vehicles? If you have then how did you know the bearing was in the right position once you had the gearbox in place?
Anyway, that is the modification we made. Next clutch change I will be laughing.
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Kowalski
- Posts: 2557
- Joined: 15 Oct 2003, 17:41
- Location: North East, United Kingdom
- My Cars: Ex 05 C5 2.0 HDI Exclusive 145k
Ex 97 Xantia 1.9TD SX 144k
Ex 94 Xantia Dimension 1.9TD 199k
When I did my clutch I did it all from the top. I rotated the bearing to the right orientation, got the fork in the right place and put the box on. As luck would have it, it only took one attempt although I could see it taking rather more. The secret seemed to be in being very careful not to disturb the fork or the release bearing once they were in alignement. I think your method of using the hole at the bottom could be helpful, even if it just means that you can see things are going together correctly.
I'd agree that generally you shouldn't be getting your clutch hot (e.g. riding the clutch and doing racing starts) but sometimes you can't it, hot weather, stop start traffic going uphill would be about the worst case scenario, and Citroen has to engineer their car so that somebody who drives in a less than perfect manner doesn't brake it straight away....
The second time you do anything its easier especially since you've got the experience from doing it once before and know what you're doing i.e. Mr Haynes and associated guess work won't be required the second time around.
I'd agree that generally you shouldn't be getting your clutch hot (e.g. riding the clutch and doing racing starts) but sometimes you can't it, hot weather, stop start traffic going uphill would be about the worst case scenario, and Citroen has to engineer their car so that somebody who drives in a less than perfect manner doesn't brake it straight away....
The second time you do anything its easier especially since you've got the experience from doing it once before and know what you're doing i.e. Mr Haynes and associated guess work won't be required the second time around.
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Kowalski
- Posts: 2557
- Joined: 15 Oct 2003, 17:41
- Location: North East, United Kingdom
- My Cars: Ex 05 C5 2.0 HDI Exclusive 145k
Ex 97 Xantia 1.9TD SX 144k
Ex 94 Xantia Dimension 1.9TD 199k
I replaced my Valeo with another Valeo, since it was the cheapest I could find at the time.
How did the price of the Borg Warner compare with the Valeo?
I found that LUK, Valeo, Sachs, Quinton Hazell and NK all have part numbers for the Xantia clutch, and Borg Warner too, but the Valeo was the only one I could actually find anybody selling.
How did the price of the Borg Warner compare with the Valeo?
I found that LUK, Valeo, Sachs, Quinton Hazell and NK all have part numbers for the Xantia clutch, and Borg Warner too, but the Valeo was the only one I could actually find anybody selling.