Killed my '69T's motor.

[daniel911T]

I was accelerating hard in my '69 and the pedal went down to the floor, felt like it had a little bit of resistance, then kept going. When I went to shift, the pedal didn't come back up.

The accelerator stuck, the motor overrevved and now is making horrible and very expensive loud percussive noises. I think it's a rod knock, but it may also be a bent valve. It really doesn't matter - the point is that she's going to need a heart transplant someday.




A picture is worth a thousand words... if you look at the gold part on the far right, that's the accelerator linkage. The rod sticking out of it goes into the back of the pedal.

If you push it too hard, the metal at the pivot can bend. When it bends, it goes to the right gets caught under that curved piece of the body behind the pedal cluster. If it goes that far, then it continues to bend and gets REALLY stuck... like get crowbar stuck.

This happened to me once before, but I was on the highway, and the engine wasn't running well at the time, so it didn't run away too bad. I replaced that gold part - it's a high failure item anyway - and figured I'd be good for the life of the car. I probably would have been, but I was working on it with a friend a couple of weeks ago, adjusting the brake light switch, and while trying to reconnect the accelerator he used far too much force and bent the linkage. I was able to bend it back, and I have been planning to replace it ever since, but I guess I waited a little bit too long.

To add a bit of insult to injury - this shouldn't be possible in the first place - there's supposed to be a stop behind the pedal, but the board that goes there rotted away - it was wood. I replaced it with a much nicer plastic part, but it didn't come with a pedal stop and I hadn't gotten around to installing one yet.

... and as a final insult... I have an MSD 6AL - which has a rev limiter. The stupid little white chip fell out. I found it under the MSD.

Here's what it sounds like now:
https://drive.google.com/file/d/0B3FTemCCwQV3cE45TmxEd1NqaHM/view?usp=sharing

Any ideas?

[porsche930dude]

yep sounds like a bent valve. the ticking is the large amount of valve lash from it not closing all the way. Rod knock sounds more like a knock

[dad911]

Stop running it and do a leakdown test... that 1 minute video was 55 seconds too long......

[Jose_JGC]

That sucks. I had that accelerator linkage part on my 1970 911T bent and get stuck a couple of times, but I was lucky I switched the ignition off fast enough and avoided over-revving too long. I welded a reinforcement on it and it has been working fine for about 8 years now.
It is an item that should be replaced or reinforced in every early 911 as it might cause accidents or engine damage.
Jose

[suckho]

Was that part replaced by the factory at some point? When?

I had similar situation last summer when my throttle return spring (there should have been two but my car had just one!) broke during kick down. Not fun at all, but I managed to stop her without damage. Now I have both springs and regularly keep checking that they are still in place

[daniel911T]

It also isn't too bad a problem if you have a throttle stop installed. Sadly, my floorboard rotted away and the nifty new one from Pelican, made of ABS, didn't include the stop.

I had all the parts and actually was going to install the stop the day before, but the place I was working didn't have an adequate drill bit set.

[unclebilly]

We had a co-driver in our first chump car race who kept bending that 'gold' part and eventually broke it. He is a legitimate retard... I hope he treats his cup car better.

Just thinking about this gets my blood pressure up!

I had to weld it and put in a gusset to keep it from bending.

[SiberianDVM]

Originally Posted by unclebilly

We had a co-driver in our first chump car race who kept bending that 'gold' part and eventually broke it. He is a legitimate retard... I hope he treats his cup car better.

Just thinking about this gets my blood pressure up!

I had to weld it and put in a gusset to keep it from bending.

You run a 911 in ChumpCar? Has to be EC? Awesome! My entire CCWS team is comprised of PCA instructors, with the exception of me. They can drive; we just need a better car.

[Dan J]

The bellcrank bends when the throttle stop is not adjusted correctly or is missing
The throttle stop is supposed to stop the pedal not the linkage

[dicklague]

get rind of that MSD too and get a real CDI There are some good ones around and they don't use that stupid plug or jumper in the MSD!

[daniel911T]

Throttle stop will be installed before the engine is repaired. That's not going to happen again!

What would you suggest as an alternative to MSD? I've worked with the Crane system too and I liked it, but this MSD has been soldiering along for 10 years without missing a beat... except for that stupid rev limiting chip falling out.

I need to find someone that welds to reinforce the new bellcrank I'm going to have to buy. That stupid piece of SH@# has failed me for the last time.

[Driver_X]

The new MSD got rid of the chip. Replaced with adjustable dials on the unit.

[tirwin]

The MSD StreetFire uses dials too. I'm using it in my '83 with great success.

[bgyglfr]

Dan, Bummer to hear about the motor. Which way are you heading? If you come through near me stop and we can throw her on the lift and do a diagnosis.