TheSamba.com :: View topic - Rattle noise in neutral and clutch engaged (not pressed in)

Wed Oct 18, 2017 5:25 pm

Well, back from my end of summer blow out trip and the ole girl is going in the garage to start some winter maintenance. Big item to tackle this year is a rattle noise I get when the van is in neutral and the clutch is out. It is more of a "rythmic" rattle that seems to follow the idle speed of the engine. I don't notice the rattle while in gear and no problems with shifting or response. Any ideas?

Edit: forgot to mention 84 manual, and title because of some confusion

Wed Oct 18, 2017 5:33 pm

My first thought based on experiencing this on other vehicles is that the throw out bearing is on its way out.

Wed Oct 18, 2017 5:53 pm

Ahwahnee wrote: My first thought based on experiencing this on other vehicles is that the throw out bearing is on its way out.

Unless by "clutch out" you mean transmission engaged and turning in neutral. I just had this problem in mine, just got it back from a rebuild, the main shaft bearing was moving around. I could hear it (and feel it by touching the transmission). Push the clutch pedal and it would go away. It was driving normally except I started hearing it occasionally at speed as well.

I think Ahwahnee is right if you hear it only when you push the clutch pedal.

Wed Oct 18, 2017 6:33 pm

NG. Same deal as you are describing. Depress clutch and it goes away. Let off and it comes back.

Wed Oct 18, 2017 6:52 pm

I'll verify this when I next fire up the old girl but this sounds a lot like what I have been experiencing recently. Clutch pedal out, rattling: pedal depressed, no rattle. Not news I wanted…

Wed Oct 18, 2017 7:07 pm

A throwout bearing can make noise with the clutch out, and it goes away when clutch depressed. Wish for this.

AZ_CreamPuff wrote: rattle noise I get when the van is in neutral and the clutch is out. It is more of a "rythmic" rattle that seems to follow the idle speed of the engine.

The worse diagnosis is.....Engine speed ==> mainshaft speed ==> transmission "mainshaft bearing ==> total transmission rebuild"

And, drumroll please.....cuz Sodo's gonna suggest that you check your transmission drainplug magnet. If your mainshaft bearing is making noise there will be lots of metal in your gear oil. You could perhaps just remove the filler plug and probe the _______ with your finger, see if it comes out covered with glitter.

Wed Oct 18, 2017 7:29 pm

If the noise goes away with the clutch pedal to the floor (disengaged) it is the pilot bearing (input bearing). If it persists with the clutch to the floor then it’s the throw out bearing. If I’m reading your description right, it’s the pilot bearing that’s bad.

Wed Oct 18, 2017 8:42 pm

So sounds like it could be a number of things. With a clutch kit I can replace the pilot and throw out bearing. Is it worth it to do the main shaft bearing while in there?

I replaced the tranny fluid last spring and there wasn't an abnormal amount of metal on the plug, and it was doing the same thing at the time. Hopefully no transmission rebuild....

Wed Oct 18, 2017 10:59 pm

AZ_CreamPuff wrote: Is it worth it to do the main shaft bearing while in there?

Sorry, but mainshaft bearing requires total transmission disassembly.

AZ_CreamPuff wrote: I replaced the tranny fluid last spring and there wasn't an abnormal amount of metal on the plug, and it was doing the same thing at the time. Hopefully no transmission rebuild....

Many people consider lots of metal on the plug as "normal" because nobody changes transmission oil and its seen often on transaxles that are dying. Everyones has lots of metal because they don't change their oil. So they think it's normal. Which under such conditions, it is normal, and you are killing your trans "normally". Everybody's trans has 150, 250k miles, often with severe non-maintenance, so yeah it's "normal". Owners are destroying their trans much faster than they need to. It's unnecessary, because changing gear oil is not expensive. The shorter life can be disappointing.

When your trans starts to "make metal" (of which the magnet gathers up some of it) that's your cue to change oil SOONER next time. Your trans is OLD - obviously. New cars can run 30,000 miles on one batch of gear oil. Yours can't and it told you that last year by showing you the metal on the drain magnet. It can't run 30,000 miles in its own barf.

Metal in your lubricant significantly reduces the lubricating ability of your oil, the result being accelerated wear. And more metal, and more damage, snowballing to total failure.

Not your fault, as it's a very popular misconception. Experienced mechanics will tell regular people that they don't have to change gear oil. They're right, they don't have to. But the trans won't last anywhere near as long (except some do with luck).

Thu Oct 19, 2017 1:10 am

Sodo,
your theorie will not become more true if you write it more often.

A gearbox with old gears and shafts do not "make more metal" with new bearings than a new gearbox.

A trans "makes metal" is a normal thing and depends on the age of the bearings and the load you put on it. Not from old gearings or shafts and not from "old" oil.

If we take a "normal" used gearbox, it has "normal" conterminated oil after 100k and still runs another 100k without problems.
If you maintain this box until overused bearings lead to a damage on shafts or gears, you can use this box another 200k without oil changes.
The most importand is to know when your bearings are overused to a point they start to change the position of shafts/gears to a point where they start to take damage/piting. In most cases you can hear this before the damage.

Once more,
the boxes are not beeing destroyed because of "not oil changing".

And yes, you can replace your oil as often you wisch.
It will not hurt your box, but it will also not save it from total damage if you dont change the bearings if needed.

Thu Oct 19, 2017 6:05 am

>>Waldi, I have noticed your thoughts on this before and I know you are a smart guy, so thought I would enter this conversation because it seems I am missing something. I want to understand your view on this so I can think about it.

A gearbox with old gears and shafts do not "make more metal" with new bearings than a new gearbox.
>> I think it would simply because the worn gears would have more wear taking place even with new bearings as the worn gears are not precise.

A trans "makes metal" is a normal thing and depends on the age of the bearings and the load you put on it. Not from old gearings or shafts and not from "old" oil.
>> I feel old oil definitely "makes metal" at a higher rate by carrying abrasive metal into bearing surfaces and gear faces - accelerating wear. A trans "makes metal" is normal, but you can "make MORE metal" with old oil. Yes?

If we take a "normal" used gearbox, it has "normal" conterminated oil after 100k and still runs another 100k without problems.
If you maintain this box until overused bearings lead to a damage on shafts or gears, you can use this box another 200k without oil changes.
The most importand is to know when your bearings are overused to a point they start to change the position of shafts/gears to a point where they start to take damage/piting. In most cases you can hear this before the damage.

Once more,
the boxes are not beeing destroyed because of "not oil changing".
>> I actually feel that "not oil changing" is the #1 cause of gear box wear. Fresh oil produces minimum wear, contaminated oil (that means metal in oil) produces maximum wear.

And yes, you can replace your oil as often you wisch.
It will not hurt your box, but it will also not save it from total damage if you dont change the bearings if needed.[/quote]
>> Agree but if you change the oil more frequently, you will change the bearings LESS frequently, right? I am having a hard time that it seems you do not accept that fresh oil in a gear case is a good thing, and that it reduces wear and extends component life. Are you saying you do not accept that, or perhaps I am missing something and you are only saying it is not a cost savings? Or that you'd prefer to wear out bearings and change them instead of change the oil.

>> I sincerely am trying to understand because I respect your opinion and feel that I am missing something here.

Doug

Thu Oct 19, 2017 7:30 am

It depends where the metal is coming from. While the synchronizer ring is brass, it only aligns the slider hub and gear face. So, every shift is metal on metal. Manufacturers put magnets even in automatics to collect metal particles. Its all part of normal wear and tear. A failing bearing is another problem all together.

For the noise, clutch out had me thinking. But another possibility is over time the rotational springs in the clutch disc can wear. They will actually rattle enough so that you can hear them idling with your foot off the clutch. This was more pronounced on diesel clutches, but the springs do wear on all discs. When you have the clutch in your hands, check the springs, they should be snug.

Thu Oct 19, 2017 9:08 am

Waldi wrote: Sodo,
your theorie will not become more true if you write it more often.

Not a theorie (IMHO :roll: )
Its not is "written often" for added trueness. Contamination of your lubricant degrades the life of all bearings, shafts, gears in the trans, this is a physical reality for every mechanical device in the world. More contamination = shorter lifetime. But your point is, what if the 3-4 hub breaks? Or the van BURNS tomorrow? Or van is stolen. In that case fresh oil was a waste of time you are right.

It is not written often simply to bother the member who already read it 2 years ago. If the forum must decline repeating info because one member knows it from 2 years ago, it's a useless forum. TheSamba is good because ppl can drive their van for 2 years then log on when they have a question, and SAMBA members will HELP.

There are lots of trans problems, a steady stream,,,, another every week. And there will be more, because ALL trans in a vehicle discontinued 30 years ago are getting old, and require a higher level of maintenance. And many have bigger engines. Luckily, changing oil is a doable task (for many) and not expensive for the rest to take it to the oil-change shop. It's something members can DO, that will result in longer trans life. It's a big problem for our vans because the trans is very expensive now (to repair) and very OFTEN neglected as a maintenance item, requiring continual education. With apologies to the ppl who know, this is for those who don't know. And there are many. And for those who resist. :wink:

Waldi I like to read your posts. But this idea of yours, that members can replace their treansaxle bearings every 100k (= 62k miles) does not work in the USA. It's hard enough to get them under the van to change their gear oil every 62,000 miles. Or 30k mi. Or 15k mi for a trans that has a few hi-mileage parts shedding metal into the oil... :wink:

So this noise the OP hears could be from the clutch, with luck. Because those items can be changed in the driveway. But since ALL trans are getting old, it's just as likely to be inside the trans. :shock: Hope not.

Thu Oct 19, 2017 2:10 pm

Sodo wrote: Waldi wrote: Sodo,
your theorie will not become more true if you write it more often.

Not a theorie (IMHO :roll: )

It is not written often simply to bother the member who already read it 2 years ago. If the forum must decline repeating info because one member knows it from 2 years ago, it's a useless forum. TheSamba is good because ppl can drive their van for 2 years then log on when they have a question, and SAMBA members will HELP.

So this noise the OP hears could be from the clutch, with luck. Because those items can be changed in the driveway. But since ALL trans are getting old, it's just as likely to be inside the trans. :shock: Hope not.
Damn, you're patient!! Working on canonization? 8)

Thu Oct 19, 2017 3:09 pm

Thanks for all the input guys, I really appreciate it. I'm going to do a clutch rebuild kit likely from VC. Hopefully that solves the problem. I'm sure you will be hearing from we when that process goes down. Luckily for me I live super close to Arizona Transaxle exchange if it doesn't work. Unlucky for the wallet I suppose.

Things I should do while in there?
1. Rear main seal
2. Repack CV's
????

Or should I just take it down there now. Hmmmmm.

Thu Oct 19, 2017 4:44 pm

AZ_CreamPuff wrote: Or should I just take it down there now. Hmmmmm.

Here's a proposal.

Look at your drain magnet. I think you wrote ithat it was clean one year ago. If after one year, there are bare areas on the magnet end, you can conclude that your trans is healthy. Then focus on the clutch or other sources of the sound.

If the magnet is covered with metal in one year, (no bare surface showing) then start saving a couple thou$and etc for AZ Transaxle. The clutch can be inspected or replaced while the trans is out.

Or just take it there and have them do it all. But TheSamba wants to discuss/learn something, so we want you to take your plug out and post pics.

Thu Oct 19, 2017 5:36 pm

Sodo. Will do, I'll try and get to it this weekend and will post some pics of the results.

Fri Oct 20, 2017 1:47 am

>>Waldi, I have noticed your thoughts on this before and I know you are a smart guy, so thought I would enter this conversation because it seems I am missing something. I want to understand your view on this so I can think about it.

Yes you do

A gearbox with old gears and shafts do not "make more metal" with new bearings than a new gearbox.
>> I think it would simply because the worn gears would have more wear taking place even with new bearings as the worn gears are not precise.

If the gears/r+p would not be prcise theay should be changed or they would be destroyed in short time. They are only not precise if the change position due to worn out bearings.
The only case where the metal comes from gears is if the synchronizers are worn out and the driver ignors ist and hammers the gears in. But this is not metal from a normal running box.

A trans "makes metal" is a normal thing and depends on the age of the bearings and the load you put on it. Not from old gearings or shafts and not from "old" oil.
>> I feel old oil definitely "makes metal" at a higher rate by carrying abrasive metal into bearing surfaces and gear faces - accelerating wear. A trans "makes metal" is normal, but you can "make MORE metal" with old oil. Yes?

Hard to argue against "feelings and believings" with fakts and practical experiance.

If we take a "normal" used gearbox, it has "normal" conterminated oil after 100k and still runs another 100k without problems.
If you maintain this box until overused bearings lead to a damage on shafts or gears, you can use this box another 200k without oil changes.
The most importand is to know when your bearings are overused to a point they start to change the position of shafts/gears to a point where they start to take damage/piting. In most cases you can hear this before the damage.

Once more,
the boxes are not beeing destroyed because of "not oil changing".
>> I actually feel that "not oil changing" is the #1 cause of gear box wear. Fresh oil produces minimum wear, contaminated oil (that means metal in oil) produces maximum wear.

So how you explain with your "feelings" that a box can run 200k without oil changes and still good parts inside ? Change bearings and run it again 200k. And again. And again ?
While you can worn out the bearings even in a stock engine within 100k if running steep up and downhill in 1st ?
Number one of wear for the bearings is load.
No worn out bearings, no broken other parts (which has nothing to do with oil) no damaged gearbox parts (r+p, shafts, gears).
No matter if old oil or new oil.

And yes, you can replace your oil as often you wisch.
It will not hurt your box, but it will also not save it from total damage if you dont change the bearings if needed.[/quote]
>> Agree but if you change the oil more frequently, you will change the bearings LESS frequently, right? I am having a hard time that it seems you do not accept that fresh oil in a gear case is a good thing, and that it reduces wear and extends component life. Are you saying you do not accept that, or perhaps I am missing something and you are only saying it is not a cost savings? Or that you'd prefer to wear out bearings and change them instead of change the oil.

>> I sincerely am trying to understand because I respect your opinion and feel that I am missing something here.

What is the goal ?
To drive the box to total damage as long as possible ?
Or to avoid a total damage ?

If the first, ok, the bearings may last 20k longer under same load with cleaned oil, and you get broke on the street 20k later, due to another broken part that has nothing to do with the oil, or just because your bearings were worn out 20k later and you have ignored it.

As for metal dust grinding.
Take the stuff from the magnet drain plug and try to grind hardened metal with it.
You will be not succesfull, and thats why all parts exepts the bearings which run under load, are not worn out in a box running 200k in its oil.
Isnstall a worn out main bearing with oil cooling and filtering and your box is trash after short time.

Cleaning/changing oil is a waste of money and time.
As many other things too, we do on out vans.
If you want to check the drain plug, let the oil out, leave it over night alone, use it again. If it is the first original filling, ofc it makes sense to change it for new, but not full synthetic. But if the box has far over 100k its wasted money.
What to do to avoid a total damage of the gearbox, was told by me before

[/b]

Fri Oct 20, 2017 2:24 am

Waldi wrote: Sodo,
your theorie will not become more true if you write it more often.

Not a theorie (IMHO :roll: )
Its not is "written often" for added trueness. Contamination of your lubricant degrades the life of all bearings, shafts, gears in the trans, this is a physical reality for every mechanical device in the world. More contamination = shorter lifetime. But your point is, what if the 3-4 hub breaks? Or the van BURNS tomorrow? Or van is stolen. In that case fresh oil was a waste of time you are right.

That is not what i see on a 200k box that was running all the time on original oil. Only worn out bearings that run under load. If they are not worn to much, all other bearings and parts inside the box are without wear.

It is not written often simply to bother the member who already read it 2 years ago. If the forum must decline repeating info because one member knows it from 2 years ago, it's a useless forum. TheSamba is good because ppl can drive their van for 2 years then log on when they have a question, and SAMBA members will HELP.

you dont help ppl saying them "chage the oil and you wont get broke on the street couse of a broken box"

There are lots of trans problems, a steady stream,,,, another every week. And there will be more, because ALL trans in a vehicle discontinued 30 years ago are getting old, and require a higher level of maintenance. And many have bigger engines. Luckily, changing oil is a doable task (for many) and not expensive for the rest to take it to the oil-change shop. It's something members can DO, that will result in longer trans life. It's a big problem for our vans because the trans is very expensive now (to repair) and very OFTEN neglected as a maintenance item, requiring continual education. With apologies to the ppl who know, this is for those who don't know. And there are many. And for those who resist. :wink:

Waldi I like to read your posts. But this idea of yours, that members can replace their treansaxle bearings every 100k (= 62k miles) does not work in the USA. It's hard enough to get them under the van to change their gear oil every 62,000 miles. Or 30k mi. Or 15k mi for a trans that has a few hi-mileage parts shedding metal into the oil... :wink:

The 100k is not a fix number. The interval depends alot of driving style, load on your box.
Get 100-200 boxes disansambled and checked, than you will understand what i am writing.
Or get in contact with ingeneers that run tests on new gearboxes, which simulates around 200k/10 years street use. They will tell you, that if there would be worn out gears/r+p, due to the metal in the oil, this gearbox would not go into a car.
May be your prices for overhauling a box are double as ours, but you gain for your work also double money than we. Ppl here work not seldom for 10€ per hour. Our minimum €/hour per law is something 8,70.
But no matter, it is still better to pay for a gearbox work every 100k, than to pay for oil cleaning/changing and to get broke on the street/new gearbox.

So this noise the OP hears could be from the clutch, with luck. Because those items can be changed in the driveway. But since ALL trans are getting old, it's just as likely to be inside the trans. :shock: Hope not.[/quote]

Fri Oct 20, 2017 3:11 am

Waldi wrote: Or get in contact with ingeneers that run tests on new gearboxes, which simulates around 200k/10 years street use. They will tell you, that if there would be worn out gears/r+p, due to the metal in the oil, this gearbox would not go into a car.

A gearbox having no problems until 150k km ??? (or some chosen lifetime) is perfect engineering. The gearbox has survived, the customer is satisfied, and the manufacturer is pleased because the old Vanagon has retired, and is no longer blocking new car sales. Much of engineering is to satisfy sales goals. For example your vehicle battery has an engineered lifetime, and your iPhone software, and your internet speed. All engineered, with a limit based on sales goals.

This discussion (of extending transaxle lifetime) is for the antique vehicle owner.

ooopps... prob let the OP continue his thread, he has a specific problem to discuss :oops: