Questions about choosing the right clutch kit from Marlin Crawler

1. What's the practical difference between a 900 & 1200 foot pound pressure
plate? (yes, I know, 300 foot pounds).
2. Do you bother replacing non torque to yield pressure plate bolts?
3. Do you change the teeth spacing in your flywheel?

I called Marlin Crawler (+1-559-252-7295) today who does not offer an OEM
spec 900 foot pound pressure plate in any of their 5-piece clutch kits.

The only kit they have to fit my vehicle is the MCCL-128 for $300
* Aisin 1200 pound pressure plate
* Seico clutch with steel springs
* Nachi pilot bearing
* Nachi throwout bearing
* Plastic spline alignment tool
<https://www.marlincrawler.com/clutch/heavy-duty/clutch-tacoma/1995-04-4cyl-1200-lb-clutch-kit>

They recommend pressure plate bolts even though they mentioned they're not
"torque to yield", whatever that means to me in practice:
* MCHT-411
<https://www.marlincrawler.com/hardware-tools/hardware/heavy-duty-pressure-plate-bolt-kit>

They also sell a flywheel where you can specify the teeth spacing, again,
whatever that means to me in practice:
* MCCL-221A
<https://www.marlincrawler.com/clutch/flywheel/flywheel-i4-27-liter>

1. What's the practical difference between a 900/1200 pound pressure plate?
2. Do you bother replacing non torque-to-yield pressure plate bolts?
3. Do you change the teeth spacing in your flywheel? Why?

In article >, lid says...
>
> 1. What's the practical difference between a 900 & 1200 foot pound pressure
> plate? (yes, I know, 300 foot pounds).
> 2. Do you bother replacing non torque to yield pressure plate bolts?
> 3. Do you change the teeth spacing in your flywheel?
>
> I called Marlin Crawler (+1-559-252-7295) today who does not offer an OEM
> spec 900 foot pound pressure plate in any of their 5-piece clutch kits.
>
> The only kit they have to fit my vehicle is the MCCL-128 for $300
> * Aisin 1200 pound pressure plate
> * Seico clutch with steel springs
> * Nachi pilot bearing
> * Nachi throwout bearing
> * Plastic spline alignment tool
> <https://www.marlincrawler.com/clutch/heavy-duty/clutch-tacoma/1995-04-4cyl-1200-lb-clutch-kit>
>
> They recommend pressure plate bolts even though they mentioned they're not
> "torque to yield", whatever that means to me in practice:
> * MCHT-411
> <https://www.marlincrawler.com/hardware-tools/hardware/heavy-duty-pressure-plate-bolt-kit>
>
> They also sell a flywheel where you can specify the teeth spacing, again,
> whatever that means to me in practice:
> * MCCL-221A
> <https://www.marlincrawler.com/clutch/flywheel/flywheel-i4-27-liter>
>
> 1. What's the practical difference between a 900/1200 pound pressure plate?
> 2. Do you bother replacing non torque-to-yield pressure plate bolts?
> 3. Do you change the teeth spacing in your flywheel? Why?

My thoughts are the more foot pounds would do two things, make the clutch
harder to push, but at the same time make the clutch slip less likely.
Many clutch bolts are designed to stretch when tightened and should not
be reused. Teeth on the flywheel do not change, they are only for starter
motor to flywheel function.

--
RonNNN

On 14/11/2017 11:36 AM, harry newton wrote:
> 1. What's the practical difference between a 900 & 1200 foot pound pressure
> plate? (yes, I know, 300 foot pounds).
> 2. Do you bother replacing non torque to yield pressure plate bolts?
> 3. Do you change the teeth spacing in your flywheel?
>
> I called Marlin Crawler (+1-559-252-7295) today who does not offer an OEM
> spec 900 foot pound pressure plate in any of their 5-piece clutch kits.
> The only kit they have to fit my vehicle is the MCCL-128 for $300
> * Aisin 1200 pound pressure plate
> * Seico clutch with steel springs
> * Nachi pilot bearing
> * Nachi throwout bearing
> * Plastic spline alignment tool
> <https://www.marlincrawler.com/clutch/heavy-duty/clutch-tacoma/1995-04-4cyl-1200-lb-clutch-kit>
>
>
> They recommend pressure plate bolts even though they mentioned they're not
> "torque to yield", whatever that means to me in practice:
> * MCHT-411
> <https://www.marlincrawler.com/hardware-tools/hardware/heavy-duty-pressure-plate-bolt-kit>
>
They may be of a higher grade than the originals. After all, the
pressure on them would be higher with the stronger pressure plate.
>
> They also sell a flywheel where you can specify the teeth spacing, again,
> whatever that means to me in practice:
> * MCCL-221A
> <https://www.marlincrawler.com/clutch/flywheel/flywheel-i4-27-liter>

Different applications, different starters. It would be something you
would want to check to make sure you get the correct tooth spacing for
your application.
>
> 1. What's the practical difference between a 900/1200 pound pressure plate?

300 pound extra clamping pressure on the clutch plate. Ergo, reduced
likelihood of slippage under extreme conditions.

> 2. Do you bother replacing non torque-to-yield pressure plate bolts?

Normally no but when installing heavier duty components I would highly
recommend it.

> 3. Do you change the teeth spacing in your flywheel? Why?

No because it will no longer match your starter pinion. Measure and
purchase the correct spacing for your own application.


--

Xeno

He who is Xeno said on Tue, 14 Nov 2017 15:35:55 +1100:

> 300 pound extra clamping pressure on the clutch plate. Ergo, reduced
> likelihood of slippage under extreme conditions.

There must be a tradeoff, simply because there always is a tradeoff.

I get the 1/3 greater clamping, so, in *extreme* loads, like towing a
trailer up the Sierra Nevada mountain range, the 1200 pound should slip
less.

What happens under normal loads?
Nothing different?

He who is RonNNN said on Mon, 13 Nov 2017 22:07:30 -0600:

> My thoughts are the more foot pounds would do two things, make the clutch
> harder to push, but at the same time make the clutch slip less likely.

I can't possibly disagree as it's a huge 1/3 more torque, but Marlin
Crawler said it's about the same pedal force. Makes no sense, right?

Then I asked what's the difference and they say the obvious, which really
doesn't tell me much practically, which is that the clutch plate is against
the flywheel with 1/3 more force.

What I don't get is what that means, practically, to me?

I guess if I habitually tow a trailer up the Sierra Nevada mountain range
that I'd want "more force" against the flywheel ... but what does it mean
for "normal driving".

What's the tradeoff?

> Many clutch bolts are designed to stretch when tightened and should not
> be reused. Teeth on the flywheel do not change, they are only for starter
> motor to flywheel function.

I think I'll get the bolt kit and I won't change the flywheel teeth.
I can't imagine why they even offer that.

On 14/11/2017 4:30 PM, harry newton wrote:
> He who is Xeno said on Tue, 14 Nov 2017 15:35:55 +1100:
>
>> 300 pound extra clamping pressure on the clutch plate. Ergo, reduced
>> likelihood of slippage under extreme conditions.
>
> There must be a tradeoff, simply because there always is a tradeoff.

Higher *initial* pedal pressure required is about all I can think of.
It's a diaphragm type pressure plate so the highest pedal force required
is at the beginning of pedal travel but this reduces once the diaphragm
gets towards overcentering. This makes it much easier to *hold* the
clutch pedal in the disengaged position. Bit of info here;

http://what-when-how.com/automobile/...ch-automobile/

In that way it is vastly different from the coil spring type pressure
plate where pedal pressure starts out high - and gets higher the further
the pedal is depressed.
>
> I get the 1/3 greater clamping, so, in *extreme* loads, like towing a
> trailer up the Sierra Nevada mountain range, the 1200 pound should slip
> less.
>
> What happens under normal loads?
> Nothing different?

Exactly. It should give a firmer takeup however.

--

Xeno

On 14/11/2017 4:30 PM, harry newton wrote:
> He who is RonNNN said on Mon, 13 Nov 2017 22:07:30 -0600:
>
>> My thoughts are the more foot pounds would do two things, make the
>> clutch harder to push, but at the same time make the clutch slip less
>> likely.
>
> I can't possibly disagree as it's a huge 1/3 more torque, but Marlin
> Crawler said it's about the same pedal force. Makes no sense, right?

It's the way diaphragm plate clutches work.
>
> Then I asked what's the difference and they say the obvious, which really
> doesn't tell me much practically, which is that the clutch plate is against
> the flywheel with 1/3 more force.
>
> What I don't get is what that means, practically, to me?
>
> I guess if I habitually tow a trailer up the Sierra Nevada mountain range
> that I'd want "more force" against the flywheel ... but what does it mean
> for "normal driving".
>
> What's the tradeoff?
>
>> Many clutch bolts are designed to stretch when tightened and should
>> not be reused. Teeth on the flywheel do not change, they are only for
>> starter motor to flywheel function.
>
> I think I'll get the bolt kit and I won't change the flywheel teeth.
> I can't imagine why they even offer that.



--

Xeno

On Tue, 14 Nov 2017 00:36:19 +0000 (UTC), harry newton
> wrote:

>1. What's the practical difference between a 900 & 1200 foot pound pressure
>plate? (yes, I know, 300 foot pounds).
>2. Do you bother replacing non torque to yield pressure plate bolts?
>3. Do you change the teeth spacing in your flywheel?
>
>I called Marlin Crawler (+1-559-252-7295) today who does not offer an OEM
>spec 900 foot pound pressure plate in any of their 5-piece clutch kits.
>
>The only kit they have to fit my vehicle is the MCCL-128 for $300
>* Aisin 1200 pound pressure plate
>* Seico clutch with steel springs
>* Nachi pilot bearing
>* Nachi throwout bearing
>* Plastic spline alignment tool
><https://www.marlincrawler.com/clutch/heavy-duty/clutch-tacoma/1995-04-4cyl-1200-lb-clutch-kit>
>
>They recommend pressure plate bolts even though they mentioned they're not
>"torque to yield", whatever that means to me in practice:
>* MCHT-411
><https://www.marlincrawler.com/hardware-tools/hardware/heavy-duty-pressure-plate-bolt-kit>
>
>They also sell a flywheel where you can specify the teeth spacing, again,
>whatever that means to me in practice:
>* MCCL-221A
><https://www.marlincrawler.com/clutch/flywheel/flywheel-i4-27-liter>
>
>1. What's the practical difference between a 900/1200 pound pressure plate?
>2. Do you bother replacing non torque-to-yield pressure plate bolts?
>3. Do you change the teeth spacing in your flywheel? Why?


1200 lb clutch will build your left thigh muscle in traffic and will
grip a little tighter. Basically a truck or race modification> (Once
I'm movong I generally don't use the clutch)

Torque to yeild bolts are "stretched" when tightened and must be
replaced. I don't think I've ever replaced clutch bolts - would on a
drag car, but they use automatics almost exclusively today

> 1. What's the practical difference between a 900/1200 pound pressure plate?

A stiffer feeling clutch. Probably no difference in life.

> 2. Do you bother replacing non torque-to-yield pressure plate bolts?

I would do it. I'd replace the throwout bearing and anything else in
the bell end that looks the slightest bit worn. Better to change it now
while you have it apart than have to change it later when it's not. My
inclination is also to clean everything out with naptha and to repack the
new bearing with mobil 1 grease.

> 3. Do you change the teeth spacing in your flywheel? Why?

You would do that if you wanted to use a different starter. Maybe the starter
for your model is discontinued. Maybe you have a box of cheap starters with
slightly different teeth. I have had to do it before when I could not get a
starter with the correct bendix.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

He who is Clare Snyder said on Tue, 14 Nov 2017 09:23:25 -0500:


> Torque to yeild bolts are "stretched" when tightened and must be
> replaced. I don't think I've ever replaced clutch bolts - would on a
> drag car, but they use automatics almost exclusively today

I'm gonna get the bolts but I don't think I need them, as you explained.
I'll get them because (a) they're only 7 bucks, and (b) Toyota says to use
new bolts every time.

But I agree that I can re-use the old bolts too, so I'll forget about this
for now as *choosing my first clutch kit* is the more important goal.

> 1200 lb clutch will build your left thigh muscle in traffic and will
> grip a little tighter. Basically a truck or race modification> (Once
> I'm movong I generally don't use the clutch)

I've been researching this on the side and I'm still confused, but one
thing I learned is that the torque from an engine is only about 300 foot
pounds or less (278 foot pounds according to this quick search):
<https://www.google.com/search?&q=toyota+4runner+torque+specs>

So what I don't get at all, is if an engine only generates 300 foot pounds
of torque, why would we even need a 900 foot pound pressure plate, given
that the ratio of the flywheel diameter to clutch plate diameter is fixed
at what? Almost 1 to 1? Or is it 2:1 or 3:1?

How does this math work that a 1200 foot pound clutch does ANYTHING useful?