Pointers On Driving A 30's Jowett

[AlanBartlett]

Right Ive got the jist of double de clutching, and still have a few engine bits to sort like a miss fire and other bits, but I was wondering if anyone has any pointers on driving one? like when to change gear and stuff like that

[george garside]

[quote="AlanBartlett"]Right Ive got the jist of double de clutching, and still have a few engine bits to sort like a miss fire and other bits, but I was wondering if anyone has any pointers on driving one? like when to change gear and stuff like that[/quote]

for what its worth the autocar commented in test of 1934 model that ' 3rd gear can be used freely up to about 43mph, on 2nd the maximum is just under 30mph. Howevr don't forget that was with a brand new one!

the torque comes in much lower than on a modern petrol car the maximum being at around 1400rpm, and the maximum power is at 3250 rpm., again much lower than modern petrol cars.

In the real worls this gives max torque & max power at the following road speeds, so the opperating speed in each gear should be somewhere between the two figures, depending on need for acceleration ( should read gradual increase in rate of forward velocity!) and also for hill climbing when max power needed.


gear max torque max power

4 21mph 49mph
3 16mph 39mph
2 11mph 26mph

the max speeds achieved in road test tally up very nearly with speed at wwhich max power is developed the 1934 figures being ,25 for 2nd 36/42 for 3rd & 50/55 for top.

Untill you get the feel of the car & work out what works best try changing up at 10, 20 & 30mph and down on a hill at 35, 20 & 12/15 (the latter if on 1 in 4 hill.

if 'pottering' on empty road you should be able to change up & down at the speeds that = max torque.

cruising at 40 - 45 indefinately should do no harm if all is in good order & well lubrocated as it equates to less than 3000rpm (the gearing is 15mph per 1000 revs in top.
george

Braking distances and speeds for going round corners are a matter of common sense

[AlanBartlett]

Hi george, thanks for that useful snipit of info the only downside is my speedo isnt working at the moment but as soon i do get it working your figures will be very useful

[k. rogers]

Alan, firstly, congratulations on what seems to be a 'good' fail at the MoT! You have done brilliantly to get this far and good luck with the re-test tomorrow! Do you have the instruction book for your car? If you have, look for the 'Driving Hints' section near the beginning - it takes you through step by step as if you had never driven anything before; I found this very useful when I was your age and trying to master the driving technique for my first 7. The part which always makes me smile is (I quote) "We must now watch our steering, as we are travelling nearly 20mph and our engine feels to want to go even faster." Gosh, the thrill of it............
If you don't have a book, I will copy anything you may find useful such as the above and send by email if you like.

[AlanBartlett]

Hello All,

I have some good news, it passed, and is now a road legal jowett, taxed and everything,
First time driving it well , you certainly get a lot of odd looks, all windows and sun roof open as the exhaust pipe needs some more work, but i drove it around the town and had two problems, one the coil was causing lots of missfire luckily had a spare one to use, and the propshaft had worked loose and one of the bolts had come loose, luckinily spotted it in time and was able to replace the bolt.

[george garside]

Alan

well done - I presume the bugger must have pressed the brake pedal harder!

george

[AlanBartlett]

I had to tweak each wheel by the wing nuts, but apart from that all was well, except the prop shaft incident

[Alastair Gregg]

Congrats on all that work finally paying off. Another one on the road and the marque further away still from being sidelined and forgotten. Keep an eye out for loose bits whilst fettling and settling, well spotted re the prop shaft bolt.

So what now, concours car for when we all come down Sowf to visit all you Southern Softies in 2009???

[Tony Fearn]

Nice one Alan.

Congratulations at the start of your love/hate relationship with a road legal pre-war Jowett - it's mostly on the 'love' side though.

Aren't you glad you didn't "strip the kingpins"?

The original bolts on the prop shaft couplings used to be drilled so that a 1/8th" split pin was able to go through and lock the castellated nuts after they were tightened-up.

Perhaps 'Nylock' nuts would do the same these days.

Have you come up with a name for the car?

With regard to driving the car:-

1. Always leave a lot of room between yourself and the vehicle in front.

2. Anticipation is an art form that has to be learned, so practice. It's surprising how many modern motorists think that old cars have disc brakes all round with EBD and ABS etc.

3. Concentrate all the time.

4. When changing up the box, from 1st, through the gears to top (4th) take some time between gear selections. The flywheel, which is very heavy has to slow down a bit before a higher gear is engaged.

So - first gear and accelerate until it sounds that it's not going to go any faster in that gear. Clutch in, out of first into neutral, keep clutch in - count "and two and" slowly, then select second. Do the same for all the gears as you go up the box.

Coming down the box from any gear to a lower one is a bit different, but I note you say you've mastered the double de-clutch. The trick is to rev the engine in-between clutch depressions so that the flywheel spins faster faster to accomodate the increased revs that will occur when taking up the lower gear.

So the advice is:- take time between gear changes, give the engine a chance to sort itself out.

5. Take note of what Alastair said about checking everything for tightness quite often during the next few weeks, until everything settles down, then do a periodic check.

Tony.

[Keith Andrews]

I have some good news, it passed, and is now a road legal jowett, taxed and everything,
First time driving it well , you certainly get a lot of odd looks,

Now getting your 1st taste of classic motoring
The rewards of a great effort
Well done.

[AlanBartlett]

On fettling and just tidying up loose ends, went out for a short drive to the next village, to show a friend who'd helped me out a bit with bits and bobs, and suddenly the steering hit a pot hole and just went crazy juddery irratic wobbling from side to side. Tommorrow I shall check what it is but any ideas on what it could be? I think maybe the track rod, and pull rods for the steering may need another greasing or something.

[Tony Fearn]

Hello again Alan.

This has never happened to me so I don't know how to cure it, but I suppose there could be many reasons, here's a list of things to check, but it won't be comprehensive, or in any particular order, so I hope other members will add to it as they wish.

Just for the record, how fast were you going? Were you at "maximum torque and maximum power" as George's post outlined? (ie 49 mph +)!!

Did you remember to replace all the split pins we've talked about over the past months?

Are the following nuts etc tight? :-

1. Drop arms from hub to track rod.

2. Shock absorbers.

3. Steering box steady rod to off side chassis member.

4. Steering rod fixing bolt through the silent block bush on the cross tube behind the radiator.

5. Large nut with coiled spring washer under it which holds both parts of the steering box together (split pin). Note:- there has to be some play here, it shouldn't be done-up tightly!

6. End caps of both the drop arm from the steering box to the tie bar, and the tie bar itself (split pins).

7. Wheel nuts.

8. U-bolts holding the front axle to the springs

Are the following sorted? :-

9. Are the kingpins in place? If the fixing cotter pin has worked loose a kingpin can drop down so the the top bush isn't in the equation.

10. Did you replace the shackle bolts and/or the silent block bushes at the ends of both springs and shackles, and are they tight. The front ones are difficult to reach as they are hidden by the front apron beneath the radiator surround.

11. Is the steering box's - steering column steady tube - ok. We've discussed this before. If you loosen the clamping bolt then the steady tube can be turned one way or another, you might need a stilson wrench or something to help turn it.
It has an eccentric brass bush inside so that when you turn it, it enables the cog at the end of the steering column to engage more closely with the (immovable) toothed- gear inside the steering box (depending on which way you do so as the opposite way will move the cog away from the toothed gear and slacken the 'feel' of the steering.
If the cog and gear are too tightly enmeshed, or too slack then the front wheels sometimes take on a will of their own.

12. As a matter of course, check the nuts all over the back axle, springs and shock absorbers as well.

I hope you'll find something a little out of place so that when you've sorted it, it will give you a little more confidence to go 'out and about' again.

Tony.

[AlanBartlett]

Hi Tony,

The first time it happened i was bearly doing about 10, just went round a corner, and it has a bit of a bumpy slope around it, and it just kind of irraticly shoock, thinking back on it now it seemed the the wheels were out of control from the actualy steering as there was nothing i could do correct it all i could do was slow down to a speed let them kind of gather themselves and carry on again. the list you made i shall go over that list today and see whats up.

[AlanBartlett]

Next Queiry/ Problem, is there is no oil pressure showing up on the guage, started it this morning, about to head up to the car shop to get some exhaust sealant, and read no pressure on the guage? Any ideas?, I'm gunna refill it with some fresh oil in a minute.

[george garside]

could be all or any of things Tony has listed!. The only Jowett that I owned that had that problem was a 1938 10 & I have always thought the tens moe prone than the twins.

If none of things on Tonies list it could be that the set of the springs has changed over the years resulting in change in castor angle. (the slope from vertical of the kingpins that , like the castors on a tea trolley , helps directional stability & provides some self centering action.

The cure is to fit wooden wedges between the axle & springs - this was factory approved!! to quote from handbook

"Fitting of steering wedges'
' steering wobble may be experienced when all steering mechanism appears to be in good condition. In such cases a cure may be affected by fitting taper wood packings under the front springs. The taper should be from 1/8th" down to zero and the packing should be fitted 1/8th en to the front.'

(always fit to both sides!)

george