Sticking throttle and choke knob question

[bradandjaya]

This is my first post here. Just joined up (yesterday?). I've owned a mostly original, leaf green, 1960 Bugeye for almost 10 years, and do most of the work myself. It was a "project car" when I bought it, and it could almost be a daily driver, if the driver is a little crazy. It a great little car, and I have probably spent as much time fiddling with it as driving it - that's part of the fun of course. There's always a list of projects (some big, most little) that need to be done, but more of that later.

Somehow I've misplaced my favorite reference book... So here are a few questions that I would appreciate some pointers on.

I've been fixated on the carbs recently, probably as a result of replacing the fuel line last fall; the original had 2 kinks which seemed to impair the flow of fuel. <font color="green"> Percy (named by my son after the small green engine of Thomas the Tanks Engine fame) </font> runs much better now that the fuel gets to the carbs at a reasonable rate.

I had adjusted the idle today and got it down around 800-900, much better then the 1200 rpms that were required before the new fuel line.

Now the throttle sometimes sticks around 2000 rpms. It's not the cable as I replace the old, frayed one last year. Had to drill out the remains of a PO's installing a cable on top of a cable end.

Today, after picking up my son from school, we ran some errands and I noticed that the idle was high again. After a stop at the bank, I popped the bonnet, started 'er up, and then pushed on the throttle body to get it to close. Idle was then back to 800-900. Maybe just needs a good cleaning or some lube. Any ideas?

One more - I never could figure out how to get the choke cable/knob to stay in a set position. I have to hold the (manual) choke at full or half, which can be hard on the fingers. It seems to me as though the springs are too strong, or should I be able to twist the knob and get it to stay put?

Sorry for the long post.
Thanks in advance for any help you can provide,
Brad

 

[spritenut]

On the throttle sticking problem, check the gas pedal itself.
Sand, mud, rust, and carpet fuzz can make the pedal stick a bit, or alot. Even a bent pivot pin on the hinge will make it bind.

As for the choke, 2 options....
A later style twist/lock choke cable, or a rare factory optional device that holds the choke out at whatever interval you want. A couple years ago Ragtops and Roadsters sent out a reproduction of this option free to people on their catalog list. I never opened mine, I figure it should fetch big bucks on Ebay some day /ubbthreads/images/graemlins/wink.gif
It is a clothespin /ubbthreads/images/graemlins/smile.gif clip it on the choke cable and it hold it.

Frank

 

[dklawson]

When you're checking for things that might bind the carb, do look at the pedal and things inside the car but don't forget the return springs on the carb linkage and the cams for the choke. Make sure there is a little oil on every pivoting and sliding part. BTW, I have my idle set to around 1000 but it's not uncommon for it to bounce up to 1200 or drift down to 900.

As for the choke cable, buy one for a Mk1 Mini (Mini Mania, or Seven Enterprises). There is a spring detent built into the boss that mounts in the dash. You pull out the cable to the desired point and twist it to maintain that position.

 

[bradandjaya]

Frank & Doug thanks for the advice on checking what amounts to every point in the throttle linkage. I guess a little WD-40 can't hurt.

So the manual choke control for BMC cars of this period just didn't have a standard position set feature? Is it possible that the choke return springs are too strong? There have been a number of very strange/incorrect things on this car; I wouldn't be surprised if new return springs fixed it.


Re-wired the front headlights/sidemarkers last night. No more hand signals! /ubbthreads/images/graemlins/savewave.gif

 

[dklawson]

Check out MMs price... a bit high for me!
https://www.minimania.com/web/Item/21A1202/AddedFrom/Search2%2DCHOKE/InvDetail.cfm
They also list several cables for less but they make no mention of "locking". Sadly, Seven Enterprises is no better. See:
https://www.7ent.com/detail.cfm?pageid=2113
Seven used to be a lot cheaper than MM.

I doubt your carb springs are too strong. The locking choke cables have a slot milled down the length of the shaft attached to the knob. Behind the dash, on the side of the mounting boss that attaches the cable to the dash, is a semi-circular spring clip that holds a single ball bearing against the groove in the knob's shaft. If your car originally had a locking choke it's likely that this spring has weakened or is broken. Locking choke cables may never have been available for Spridgets but if the length is right (and your pockets are deep) you could certainly use one from a Mini.

 

[bradandjaya]

Doug - my choke control shaft has the groove you mentioned. Wooo hooo! /ubbthreads/images/graemlins/grin.gif

Any idea where to find a replacement spring clip and ball bearing?

 

[bradandjaya]

Update on the sticky throttle issue: I checked if the pedal and other linkage was the cause of the throttle sticking. No amount of wiggling, pushing, or pulling made a difference.

Then I sprayed the entire throttle shaft, springs, etc with WD-40 and pumped the throttle. Bingo. Took the car for a 20 minute round trip test ride this morning: no more stuck throttle. /ubbthreads/images/graemlins/cheers.gif

<font color="red">I guess I should have reached for the WD-40 sooner.
</font>

 

[Trevor Jessie]

The only drawback to WD40 is the residual "shellac" after the product disperses. (Sheese! I can't spell today). Anyway, you might want to apply some light machine oil after everything has worked free. Just my 2 cents.

 

[dklawson]

My thought was similar about the WD-40. I've never noticed the leftover deposits but I have found it evaporates too quickly. The WD-40 should help wick some machine oil into the linkage/pivots and will work a lot longer.

The ball bearing you're missing may be something you can source from a local hardware store (not a Home Depot... check a True Value or Ace). Most small stores have flat, plastic tray assortments of misc. hardware for doors, lamps, etc. including components like small ball bearings. I think I saw similar, large cabinet assorments at Lowes in the fastener aisle/department.

The spring will be the tricky bit. I can't see the one on the Mini as the choke is hidden above the heater. From memory, the spring is a cylinder of spring-steel wrapped around the body of the choke cable. There's a split down the side of the spring which allows it to "open" when you turn the choke knob forcing the ball bearing up.

I'll give the spring some thought. There may be something you can improvise with.

 

[dklawson]

Hi again,

I looked last night and on my Mini the cable's mounting boss/guide is about 1/4" in diameter and the cylindrical spring is right behind the mounting nut on the back side of the dash. I thought that maybe a spring-type hose clamp could work for your cable... but the ball bearing would be very small and probably hard to get. I also don't know of any cylindrical spring-type hose clamps that small.

On another board where I hang out a Canadian user posted that the locking choke cables are much cheaper for him from "Mr.Mini" in Ontario ( www. mrmini.com ) The link below is to one of their PDF catalog sections:
https://www.mrmini.com/catalogue/swtc_ligt_cbl.PDF
Go to page 5 and look at item(s) 4.