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djm914-6
It's been a long time comming I suppose. The lever that the pedal pushes on has been tilting to the inboard until the throttle rod rests againts the floor board. Sometimes I'd attempt to bend it back, but most of the time I'd just del with the squeeking.

Well, there's no more squeek because the throttle lever of the pedal assemble broke off. I got the car home by bending he manual throttle lever just enough to catch the throttle cable end. I drove it by pulling back on the lever.

Now, I need some ideas. I know that the six lever isn't so common. What's the changes of having this one welded up and reattached to the pin that goes into the pedal assembly?

ClayPerrine
Contact Rich Johnson. He had 5 factory throttle bellcranks for 914/6s. I know. I sold them to him.


r_towle
post a pic...never seen one...if it can be welded, bring it on by...

Rich
mightyohm
Are the pedal assemblies for the sixes really different? I doubt it.

Weld it up or find a donor 914 pedal cluster.
Aaron Cox
the pivot plate that the gas pedal connects to is different
djm914-6
Hey Rich, What's the chances that a weld would hold?

I'd love to just buy a "new" one, but today was also my last day as my job too. Oh, I just love days like these.
Eric_Shea
The crank isn't different except for the handthrottle plate that's spot welded to it.

The rod that is broken (the lower left in the picture) is brazed (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way) in the bellcrank assembly. They usually make a clean break. And people usually screw them up by trying to weld them with a MIG or other device.

The very best CSOB solution is to have everything cleaned up nicely and take it to a local shop that does brazing (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way). I doubt they would charge you more than $10 bucks to braze it back up.

It's hard to braze (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way) it properly unless it's really clean. The brazing doesn't like to take because it was plated after the factory brazed it. Clean it up with some fine files and make sure the plating is removed. It should braze (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way) up fine after that.

Any good welding shop should be able to take it from there.

Here's one I built last weekend. I used a -4 crank and a piece from the engine lid.
r_towle
QUOTE (djm914-6 @ Nov 8 2005, 09:05 PM)
Hey Rich, What's the chances that a weld would hold?

I'd love to just buy a "new" one, but today was also my last day as my job too. Oh, I just love days like these.

cant say till i see a pic.

Probably pretty easy, but it depends upon what broke.

Rich
lapuwali
QUOTE (Eric_Shea @ Nov 8 2005, 06:08 PM)
The crank isn't different except for the handthrottle plate that's spot welded to it.

The rod that is broken (the lower left in the picture) is braised in the bellcrank assembly. They usually make a clean break. And people usually screw them up by trying to weld them with a MIG or other device.

The very best CSOB solution is to have everything cleaned up nicely and take it to a local shop that does braising. I doubt they would charge you more than $10 bucks to braise it back up.

It's hard to braise it properly unless it's really clean. The braising doesn't like to take because it was plated after the factory braised it. Clean it up with some fine files and make sure the plating is removed. It should braise up fine after that.

Any good welding shop should be able to take it from there.

Here's one I built last weekend. I used a -4 crank and a piece from the engine lid.

That would be "brazing", which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way.

"Braising" is a way to cook meat.

OK, I'll stop now...
r_towle
brazing is also much weaker than welding.

Rich
fiid
Much is a deceptive word. It's possible to get 70,000psi strength braze joints and 130,000psi is possible with stainless. I don't know what the numbers look like for welds though.

Brazing is also much lower temp than full on welding, so it's easier not to induce warping or material defects.

Brazing is crap at butt joints however. It's much better when there is an overlap.

You can also braze stuff reasonably easily with a little MAPP/Oxygen setup from Home Despot.

Personally - though - I much prefer the MIG.



Eric_Shea
Fixed... dry.gif

Being in the pedal biz, I've seen 1/2 dozen weekend weld jobs on those bell cranks (is that what they're called James?) I'd hate to see that happen to a -6 piece. But, here's where I exit stage left... it ain't my car.

P.S. Not trying to dis your welding work... I've just seen a lot of bad ones. Hell I even tried it myself. I take all mine to Troy and have him "braze" (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way) them.
lapuwali
QUOTE (fiid @ Nov 8 2005, 06:58 PM)

Brazing is crap at butt joints however. It's much better when there is an overlap.

I disagree with that. When I said scads of racing chassis, I meant spaceframes. All built using lots of small round tubes fishmouthed and butt welded together, sometimes joining a good number of them into one joint. The lower temps obviously helped in reducing warpage problems when joining a lot of tubes together. And when I said scads, I meant SCADS. Most of the F1 frames built from 1950 to 1965 were brazed spaceframes. They went to monocoque construction after that, but minor formulae, like Formula Ford, continued to use brazed spaceframes until relatively recently. A good number of aircraft frames were also made this way. The fillet of bronze at the joint naturally had a nice radius, which meant it wasn't a stress riser, which a normal weld bead will be.

Brazing can also join two dissimilar metals together, which you cannot do with fusion welding.

I have a very nice book on motorcycle chassis design, written by an engineer that designed a number of racing bikes that did quite respectably in the 70s and 80s, which advocates brazing as generally superior to any other method for making spaceframes. TIG is probably better, really, but brazing shouldn't be discounted.

lapuwali
QUOTE (Eric_Shea @ Nov 8 2005, 07:00 PM)
Fixed... dry.gif

Being in the pedal biz, I've seen 1/2 dozen weekend weld jobs on those bell cranks (is that what they're called James?) I'd hate to see that happen to a -6 piece. But, here's where I exit stage left... it ain't my car.

P.S. Not trying to dis your welding work... I've just seen a lot of bad ones. Hell I even tried it myself. I take all mine to Troy and have him "braze" (which is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way) them.

Thank you. biggrin.gif

Eric_Shea
QUOTE
but brazing shouldn't be discounted


Or misspelled! w00t.gif
r_towle
QUOTE (fiid @ Nov 8 2005, 09:58 PM)
Much is a deceptive word. It's possible to get 70,000psi strength braze joints and 130,000psi is possible with stainless. I don't know what the numbers look like for welds though.

Brazing is also much lower temp than full on welding, so it's easier not to induce warping or material defects.

Brazing is crap at butt joints however. It's much better when there is an overlap.

You can also braze stuff reasonably easily with a little MAPP/Oxygen setup from Home Despot.

Personally - though - I much prefer the MIG.

bronze is weaker than steel.
Bronze is brazing, or soldering..it is using a liquified metal alloy to glue to pieces together.

now, if the piece in question has beenbroken off ina butt joint way..or torn off, there is no reason that welding with steel mig wire, or tig...would do any harm to this piece.

I have always been a CSOB,,,if the part is an original brazed 914/6 part...get it brazed...

If the part broke(not at a brazed joint, because it would never break....brazing is so tough) then fix it with welding.

I discount brazing because of the following facts.

You cannot get paint to stick to brazing...it will always lift off, so will bondo..ask any body guy about brazing and paint....

If brazing was better than welding structurally, bridges, cars, buildings, and a wide variety of other steel connections would be done with brazing because its easier, cheaper and would produce less heat and less warping etc...

but its not the right method to fix a broken piece of steel that is under stress...

Rich

Eric_Shea
Your 914 is brazed (and they painted right over it)... biggrin.gif

There's usually two ways they break:

1. They rip (the stamped metal portion of the bell crank) down there by the rod or,

2. The brazing breaks loose. Hopefully the brazing has simply broken loose and it can be rebrazed.

The brazing does break there... it usually takes about 30 years but it can break.
r_towle
QUOTE (Eric_Shea @ Nov 8 2005, 11:09 PM)
Your 914 is brazed (and they painted right over it)... biggrin.gif


the defense rests! biggrin.gif
fiid
QUOTE (lapuwali @ Nov 8 2005, 07:14 PM)
QUOTE (fiid @ Nov 8 2005, 06:58 PM)

Brazing is crap at butt joints however. It's much better when there is an overlap.

I disagree with that. When I said scads of racing chassis, I meant spaceframes. All built using lots of small round tubes fishmouthed and butt welded together, sometimes joining a good number of them into one joint. The lower temps obviously helped in reducing warpage problems when joining a lot of tubes together. And when I said scads, I meant SCADS. Most of the F1 frames built from 1950 to 1965 were brazed spaceframes. They went to monocoque construction after that, but minor formulae, like Formula Ford, continued to use brazed spaceframes until relatively recently. A good number of aircraft frames were also made this way. The fillet of bronze at the joint naturally had a nice radius, which meant it wasn't a stress riser, which a normal weld bead will be.

Brazing can also join two dissimilar metals together, which you cannot do with fusion welding.

I have a very nice book on motorcycle chassis design, written by an engineer that designed a number of racing bikes that did quite respectably in the 70s and 80s, which advocates brazing as generally superior to any other method for making spaceframes. TIG is probably better, really, but brazing shouldn't be discounted.

Hmm. I'll yield to scads smile.gif. I saw a brazed chassis once made of box steel where each joint was made by wrapping the top and bottom of the piece it was intersecting. That was a high-school project though so probably not up to F1 standards wink.gif.

djm914-6
Still no pics of the carnage as I haven't taked the time to remove the parts (except for the brokem part of the throttle).

I think after reading this thread and looking at Erics work, that I should just got for a complete cluster. The part that broke on my car isn't just that it came off the pin, but the upright piece itself snapped. I'll remove the assembly and have Rich take a look at it. If it can be repaired with welding for the time being then great, It'll give me time to save my pennies for a rebuilt cluster. If not, then the car will sit.

Thanks to Rich for offering to help and to Eric for his service to the 914 community.
Eric_Shea
Hey, did you guys know that brazing is connecting two bits of metal using more heat than soldering, but less heat than welding; a filler material is added, usually bronze. The British usually call it "bronze welding", and scads of racing chassis were (and are) assembled that way?? laugh.gif

QUOTE
the defense rests!
Hilarious. laugh.gif

OK, here's the fun fact. Both quarters are braized to the rear panel (at least on the 5 chassis I've restored). wink.gif

David, Let me know if you want an assembly. Here's what we could do; If you want to send the bell crank with the core, I'll have Troy braze it for you. Or - just send the bell crank now and I can send you a replacement assembly with your fixed bell crank on it. You would then send the core once you get it out. If you want it (the repaired bell crank) replated it will take an additional week (that's what I would do). All that being said; that is "if" the rod has simply broken loose from the bell crank and there's no further damage. If there's further damage... we'll try. We have both the "Stock" and the "Plated" assemblies in-stock now.

And finally... go out and start soaking the 13mm MC nuts (under your suspension pan) and the floorboard 13mm's that reside in the front section of your pan. Use a good penetrant (PB Blaster or other).
r_towle
QUOTE (Eric_Shea @ Nov 9 2005, 04:45 PM)


OK, here's the fun fact. Both quarters are braized to the rear panel (at least on the 5 chassis I've restored). wink.gif


once again, you are proving the point.

I know where the bronze is, I have restored a few.

Have you looked at the bubbling paint in the area...ever wonder why there and not somewhere else....like an inch to the left or right....

I actually asked several hotrod painters in my area, they all said the same thing...these guys collectively do quite a few cars each year...they all HATE bronze...as far as paint goes...they do use if for other things, but body work is not one of them...they found that it behaves differently than steel when it comes to paint...it does not stick the same, as well or not at all (depending upon the paint product)

Now, I am not a pro-painter by any stretch, but I want to keep away when told to do so.

I was offering Dave a FREE way to fix it...might not be the way it would get rebuilt by a pedal rebuilder, but it is FREE (which is part of the title to the thread) ...proper metal finishing and you could not tell the difference, unless there is supposed to be bronze showing...

Rich
Eric_Shea
Sorry... sad.gif

Wasn't trying to be Mr. Smartypants. I thought you were joking around.

Never noticed any bubbly paint.

Didn't mean to anger you with the brazing vs. welding stuff. Do what you like. You're a good man for offering the free fix.

E.
lapuwali
Hey, I'm the Mr. Smartypants in this thread...

hide.gif
fiid
I confess to also attempting to bust a smartypants move.

hide.gif

No offense meant. All experiences are valid - I find threads like this really educational.
r_towle
i likea good argument...or discussion...none taken....

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