My mean green hornet

Test drive and she is purring along now 8)
They do make a lot of difference, very happy indeed.
Which now leads me to believe my throttle linkage and kickdown are definitely the culprits of my intermittent over-rev trouble.
Next on the list!

Oh and I also removed and greased my speedo cable today as it had the unreadable wavering behaviour.
A little better but not cured unfortunately.
Last year i replaced speedo with a NOS one along with brand new angle drives at both ends.
Guess I'm looking at a new cable now?
Is there anything else that can cause this? On the gearbox end perhaps?

Jim
 
corazon said:
Oh and I also removed and greased my speedo cable today as it had the unreadable wavering behaviour.


Is there anything else that can cause this? On the gearbox end perhaps?

Jim
Click to expand...

Rear flange bolt loose.
 
Thanks Harvey,
Would I be experiencing any other symptoms if that is the case?
Do you mean where it connects to the drive shaft?
Jim
 
corazon said:
Thanks Harvey,
Would I be experiencing any other symptoms if that is the case?
Do you mean where it connects to the drive shaft?
Jim
Click to expand...

No other symptoms I can think of other than the erratic/wavering speedo. It's the bolt that holds the flange that the front of the prop bolts to.

It's quite possible that's causing it, and it is an answer to your question, ("Is there anything else that can cause this? On the gearbox end perhaps?") but tbh I'd still expect it to be poor cable routeing or the inner cable snagging up somewhere.
 
Well I wont jump to any hasty conclusions then :)
I routed it the way it always was-but then it's always been a bit crap thinking about it :LOL:
Clearly the fewer bends the better, it's routed the same way as shown in the Hayyyyynes..
Mine comes up through behind the speaker, along behind the lower part of the glovebox and vertically up the extreme right, coming back on itself to the speedo angle drive...I can only see there being a problem at the last bend to behind the speedo, but how else can it be routed?

I'll try fiddling again tomorrow, the cable seems fine to me off the car.
Jim
 
corazon said:
..I can only see there being a problem at the last bend to behind the speedo, but how else can it be routed?
Click to expand...

The biggest problem on the routeing with a 35 box is after it goes into the tunnel, as it can end up the wrong side of the selector rods, and that gives the cable a nasty double kink as you attach it to the angle drive on the box.
 
Dave, I've lubricated both drives and the cable so I can rule that out.
Harvey i'll double check the gearbox end routing tomorrow, it is fiddly and i may have rushed that earlier.
Jim
 
I think I've cured my annoying over rev problem.
I did two things today:
Filled the gearbox correctly.
I had topped it up after losing some whilst the car was laid up, but clearly not enough- it took nearly a litre more to where it should be today :shock:
Hope i've not caused damage running it so low.
Filled up with super unleaded
Just took her out for a spin and to my surprise and joy everything was behaving just as it should.
Gear changes smooth, plenty of power and no hesitation.
I even tried to induce the bad behaviour and couldn't :D

It's more than certainly the gearbox top up that's solved it.
In hindsight, it was rather like it was slipping and then suddenly engaging..?

Either way, I'm very happy as is the car :D
Jim
 
corazon said:
It's more than certainly the gearbox top up that's solved it.
In hindsight, it was rather like it was slipping and then suddenly engaging..?
Click to expand...

It's delayed engagement rather than slip, then as you increase the revs it engages with a bump.
 
This was happening around 2000 rpm.
Is this approaching peak torque in first gear?
ie making the delayed engagement more violent in certain scenarios..
 
I've assumed you were talking about a problem engaging drive at a standstill, but if it's happening on the move it can cause a lot more problems because the box is in effect running out of fluid as there isn't any in the sump to pick up, it's all distributed throughout the box and converter. The worst thing that can happen is an uncontrolled downshift 3-2 at any speed, you've just suffered a loss of drive until the sump refills and you can pick up fluid again. It just goes to show how important getting the fluid level correct is.
 
I have been playing around with different timing, as I now have a variable advance timing light.
I have set it at 6 degrees btdc where it seems to run best with the least vibration at idle and best gear changes/power,
but i'm now not comfortable with the idle speeds.
This is quite a bit more advanced than i had it set by ear previously
I'm fairly sure the timing is at it's optimum setting now, but i want to get the idle speed lower.
In gear everything is fine, idling at 600.
However in Park it goes up to over 1000 sometimes hunting a little, which sounds way too fast and a little crazy especially if the electric fan has kicked in too.
I reckon there are some vacuum leaks which could be adding to the problem.
Certainly the manifold to servo hose looks a little tired, and there is definitely a hiss in the engine bay that i can't seem to fully locate...

I've tried backing off the idle screw but can't seem to make any difference.
Should the difference between idle in Park and Drive be so large?
I get the feeling it should be more like 800 in park..
Any ideas?

Jim
 
The big drop in engine speed between PARK/NEUTRAL and Drive is because the engine is out of tune, (normally running weak), which you have alluded to already. You want to aim for an in-gear idle speed of about 600rpm, and normal idle speed in P/N of 700/750. I always think a 100rpm drop is a nice figure.
 
A drop of 100 revs would be perfect, but how can I achieve that?
I've just had a play with the carbs.
One was definitely a lot richer than the other.
I've temporarily misplaced my colourtune, so have been using the dampers to test.
Idle speed only fell in Park when I weakened the richer of the two carbs.
I got it to around 800 but didn't feel stable enough.
So i enriched both until when i dropped the damper back into the dashpot the revs drop momentarily and recover.
They are as balanced as well as I can by ear now but probably too rich, now idling just under 1000 rpm in Park

Am i right in thinking that manifold vacuum drops when put in gear?
So when there is a vacuum leak, idle in Park could be worse affected due to the higher vacuum?

Getting there slowly :)
Jim
 
Concentrate on getting the idle running and speed correct, and once you've done that you'll find that the drop into gear will be what you're looking for. Use a proper tachometer not the one in the car. Check dwell (if appropriate) and timing before moving on to the carbs. Forget vacuum, find out if there's an air leak making it run weak, whether that's in the servo or hose, vac pipes, engine breathers etc. Weaking off the mixture normally raises the idle speed, so if doing that reduces yours I can only think it's too weak already. Think of dropping it into gear as loading up the engine (which it is) and so if everything's not set up as it should be, then that loading is going to have a greater effect, and hence a greater drop in rpm.
 
After a week or so of driving with a richer mixture, I started to get a stall upon very heavy braking to a standstill.
I'm sure I have an air leak somewhere but still haven't located it.
I'm going to replace servo hose because it's cheap and looks a little tired manifold end.
I can hear a hiss from the vicinity of the carbs but it's very hard to tell where exactly, so I'm going to rebuild them next.
Meanwhile, I found the colourtune yesterday and once again enriched both carbs to correct mixture at last.
They must have been incredibly lean prior :shock:
A short run showed the car feeling a lot more responsive, and altogether more solid to me.
Idles just under 800 dropping to 600 in gear now so vastly improved!
Jim
 
Well I have just replaced the servo hose and things have changed.
The car is idling a little smoother, and upon test drive didn't stall upon heavy braking to a standstill.
Trouble is now at idle if i stomp on the brake the rpm increases slightly and i can hear the air squash noise clearly..problem with the servo itself?
Unrelated perhaps, but annoying nonetheless is i've now lost power steering 90% of the time.
I'll check the fluid tomorrow, no lights or power in my workshop currently either :?
I was about to order a carb rebuild kit and new air filters, but should probably sort this out first now!

Nearly forgot- over the last week along with the hard braking stall, occasionally when idling at some lights for instance rpm would suddenly without warning drop to stall or very nearly and recover.
This really suggested fuel starvation I thought but couldn't work out why.
I've ordered a new fuel filter just to make sure it's not that, mine's a couple of years old now and closed chrome type which i cant clean out.
Any thoughts on these symptoms?
Thanks
Jim
 
The power steering is a different system to the brakes and not connected
I'd make sure your carbs are balanced and the mixture OK , that should sort out any change in revs when braking
 
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