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Question about oversized throttle shafts

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livinginthepast

livinginthepast

Jedi Trainee
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As I mentioned in another thread, I have the H1s back. New throttle shafts were installed.

Here's my question - do I need to ream up the throttle shaft connecting clips (I don't know what they are correctly called - see img) to accept the new throttle shafts or will they have enough give to push over the new shafts?

throttleshaftclip.JPG


Thank you for your help.

Bill
 
You probably need to try. If they'll fit, fine, and I expect they will.
Reaming spring steel isn't fun!
 
Hey there - Well, when I tried to push them on to the shafts earlier today, there was considerable resistance. It was clear they weren't going together easily. I didn't want to push too hard and risk gouging up the shafts without checking in with the list to see how others have dealt with this.

Thanks!
 
I supose I would use a bit of sandpaper on my dumore or what ever it is called. Even hand work with a small dowl with a bit of sand paper wraped around it would work, you don't need to take much off.
 
Bill, who worked on your H1'a?
What did they do and what did it cost?
(you can PM me if you want)
 
Hi Rick -
Brooklands in Tacoma did the work - cost 133$ total to install oversized shafts.
 
Hi Jack -

I took the calipers to it and we're talking about .5mm difference. I've been sanding away at it, but not getting far... Sheesh!!! :smile:
 
Got it. Found an old ball tipped bit in the tool box and opened the holes up with just a little work with the drill... All is back on track!
 
There ya go. Us shade tree guys always find a way.
 
Finally got everything adjusted (not without mishaps) - I had to fiddle with the needles - basically, I couldn't get the carbs to run rich enough. Had to reset the needles (pushing them into the piston body) about an eighth of an inch. Reinstalled..and on start, the damned car revved to 5000!!! shut off, adjusted idle/balance, adjusted mixture and it runs like a champ!

Glad that's over with!
 
yes it does!
 
And the light just went on. Miss Agatha has never idled down to 800 easly. Duh, move the needles out just a bit, like a 32ed and try again.

Boy some times it really helps to have this forum.
 
Is it possible for an idle screw to tighten itself?

Here's why I ask:

Three times now, I've left the house for a short drive around the area. On all three occassions, by the time I returned, the car was idling high.

The first time this happened I thought - crap, a vacuum leak. But I couldn't find anything. So I turned the idle screw out and the idle returned to normal. Hmm.

Yesterday it did the same thing. Came back, turned out the idle screw and all is well.

Same thing this afternoon.

Now, there isn't much room for that idle screw to back out before it becomes completely out of contact with the carb 'flange' it rests on, so I don't think it's a matter of adjusting the idle down increasingly lower each time. Rather, I'm starting to think that the screw is somehow turning itself inward - upping the idle.

Is this possible? Should I replace the spring on the idle screw? What could be causing this?

Thanks!

BillW
 
There is supose to be a spring around the idle screw. Cut one from a ball point pen. The spring of course puts tension on the screw and keeps it from vibrateing out or in.
 
maybe a drop of light duty loctite?
 
Raid mom's dresser: find a bottle of fingernail polish and put a SMALL dab on the threads of the screw right at the point where the screw goezinta the carb body. It's lacquer and will break away easily if you need to reset the idle later.

:laugh:


<span style="font-style: italic">
EDIT: Do NOT forget to put th' bottle back where ya found it!!</span> :jester:
 
Great tips everyone. I'll try locking down those threads and report back later!
 
livinginthepast said:
Is it possible for an idle screw to tighten itself?

Here's why I ask:

Three times now, I've left the house for a short drive around the area. On all three occassions, by the time I returned, the car was idling high.

The first time this happened I thought - crap, a vacuum leak. But I couldn't find anything. So I turned the idle screw out and the idle returned to normal. Hmm.

Yesterday it did the same thing. Came back, turned out the idle screw and all is well.

Same thing this afternoon.

Now, there isn't much room for that idle screw to back out before it becomes completely out of contact with the carb 'flange' it rests on, so I don't think it's a matter of adjusting the idle down increasingly lower each time. Rather, I'm starting to think that the screw is somehow turning itself inward - upping the idle.

Is this possible? Should I replace the spring on the idle screw? What could be causing this?

Thanks!

BillW
Click to expand...
I'm confused. Is there "not much room left for the idle screw to come in contact with the carb flange" because you've been continually turning it out? Does the screw return to it's previous position? Or does the car just keep idling higher and higher each time you drive it even though the screw adjustment is where you left it last? Do you think that the throttle shafts are heating up with engine heat and expanding? Causing the shaft(s)/butterfly(s)to stick open somewhat. Maybe when you press on the adjustment screw, you're rotating the linkage a little and resetting the idle. How is your throttle return spring?
 
markberry said:
I'm confused. Is there "not much room left for the idle screw to come in contact with the carb flange" because you've been continually turning it out? Does the screw return to it's previous position? Or does the car just keep idling higher and higher each time you drive it even though the screw adjustment is where you left it last? Do you think that the throttle shafts are heating up with engine heat and expanding? Causing the shaft(s)/butterfly(s)to stick open somewhat. Maybe when you press on the adjustment screw, you're rotating the linkage a little and resetting the idle. How is your throttle return spring?
Click to expand...

Good questions. I still am not convinced because it seems so unlikely, but it appears that the fast idle screw is vibrating inward. The reason I say this is because I've been struggling to get a low idle (trying for around 600 rpm - I've adjusted the idle via balancing, and the carb needles in various configurations). Anyway, to get the idle down, I have to back off the fast idle screw on the front carb almost completely and even in this condition, the idle screws on both carbs are barely turned in at all - like maybe half a turn. And with this, I'm running at about 650rpm.

Now, when I take the car out, the idle creeps up. I return to the garage and guess what, I can now turn the fast idle screw back out to reduce the idle back to 650. Because the screw is barely even turned in to begin with, it is not likely that i could repeat this exercise without the screw falling out of the if I were continually turning it out. But at this point, I'm open to any suggestions.

I'm wondering now if I need to start all over - beginning with the carb needles :smile:
 
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