Pre War Distributor Units

Keith Clements · Post by **Keith Clements** » Sun Aug 05, 2007 8:54 am

Smells like petrol to me.
Old petrol will start but then the engine will die. But if new petrol, then check carb float petrol level after it has died. If low, suspect petrol delivery, pump, pipe, filters, hole that lets air into pipe.......
If OK, suspect blocked jet in carb that makes mixture lean or sticking valve/ punctured float that floods engine.

george garside · Post by **george garside** » Sun Aug 05, 2007 8:57 am

well done! its alaways easier to sort an engine out properley once its doing any sort of 'running'.
a couple of thoughts - if it really sounds like the thump thump of a stationery engine it may only be running on one cylinder - check this when its running by shorting out each pluglead with a screwdriver from plaug terminal to cylinder (if using brass terminals) or by pulling off the plug caps one at a time whilst engine running - if removing/shorting one makes no difference to the sound that is the cylinder that is not firing. If engine stops that is the cylinder that was firing!

the other thought is that the more you haave it running the better it may get as it can take time to build up a nice film of oil on the cylinder walls which in turn helps to prevent blow by & loss of compression - I think that may be the reason some long dead engines will only come back to life with several towings round the block!

I agree with Tony's plug & points settings & assume you have been using an imperial feeler guage rather than metric.
keep chugging!
george

AlanBartlett · Post by **AlanBartlett** » Sun Aug 05, 2007 5:06 pm

For those of you that said petrol, ding ding top marks. flushed the system through and put in fresh petrol and hooray sustained running has been achived, also being idle it still seems to be running a little fast and a little loud too. Also got a few leaks from rad pipes and the oil pump and exhaust connection, also the cylinderhead connection to the casting is leaking a bit too.

Tony Fearn · Post by **Tony Fearn** » Sun Aug 05, 2007 5:53 pm

It looks like 'Big Al's invocation of the Handel masterpiece, and KC's note about fresh petrol has worked.

Well done Alan. Now George's observation about sorting an engine once it's running will prove correct.

Some of the leaks might disappear if you GENTLY tighten various bolts when the engine is warm. There's a specified way to tighten cylinder head bolts. Don't know any torque settings, but don't use too long a spanner. It's surprising how easy it is to strip threads especially if you're using 'old' nuts. The pre war cylinder head bolts spread at the bottom after the first usage, (just have a look at them, the sides should be parallell) and sometimes don't tighten up as they should the second time they're used. JCC Spares have new ones for sale if you have any problems. Remember there are two lengths. You'll need 4 long and 8 short to do both sides completely.

Tappet gap of 2 thou is to be set cold. Measure and set one tappet when the opposite similar tappet is at the top of its lift.

I'll bet you and your mum are over the moon.

What's the up-date on insurance?

Tony.

AlanBartlett · Post by **AlanBartlett** » Sun Aug 05, 2007 6:17 pm

Insurance havent really checked it out properly yet just glancing, also i can confirm it is running on both cylinders as they both produce exhaust smoke and heat up. So now Ive got to adjust the tappets to 2 thou? setting will this help make it quiter? I have tightened the cyclinder head quite a bit but it still, and it turns out it isnt the head i dont think it was a loose pipe connection from the rad. she now starts up almost every time now but a little delay is to be expected I think.

AlanBartlett · Post by **AlanBartlett** » Sun Aug 05, 2007 9:42 pm

a video clip of the engine working.

its a bit long winded but you get the drift

http://uk.youtube.com/watch?v=Wv9rp1S58tM

Tony Fearn · Post by **Tony Fearn** » Sun Aug 05, 2007 9:56 pm

Well it sounds like a 7hp Jowett engine. Seems as though the choke was on all the time. Did you fettle the mixture screw? better it running a bit rich at first without the choke, except for starting and a short time afterwards.

Double check when the points open, then if you get it running for a few minutes, whilst running, slacken off the dizzy clamp bolt and turn the dizzy one way or the other (only very slightly) to see if it makes any difference to the running. Don't forget to tippex the original position so that you can return it to the status quo if all goes pear-shaped.

Yes, 2 thou for 1934 tappets (all four).

Tony.

AlanBartlett · Post by **AlanBartlett** » Sun Aug 05, 2007 9:59 pm

Ive got a bit of a conffession to make its actually a 36 8hp engine does this make any difference?

Tony Fearn · Post by **Tony Fearn** » Fri Aug 10, 2007 8:10 pm

The engine will be basically the same I would think, but tappet, points and plug settings might be different. Give Peter Rodgers a ring, he has an 8hp and knows a lot about engines.

Tony.

george garside · Post by **george garside** » Fri Aug 10, 2007 8:50 pm

Hi Allan '36 model year engines were still 7hp. 8hp engines started for '37 model year but could of course have been made in the latter haalf of '36.
tappet settings changed at engine number 64311. up to 64310 the running setting is 2 thou after this it is 6 thou - this is increased to 12 thou when timeing valves. Some earlir engines may have the later camshaft retro fitted . those originally fitted with the later camshaft have the running clearance 6 thou stamped on the engine plate on the timing case.

george

george garside · Post by **george garside** » Fri Aug 10, 2007 9:40 pm

sorry the numbers in above posting should be 640310 & 640311
george

AlanBartlett · Post by **AlanBartlett** » Fri Aug 10, 2007 9:42 pm

I might have got the wrong year me thinks, the engine number is 746090

george garside · Post by **george garside** » Fri Aug 10, 2007 9:56 pm

this is definately an 8 and the correct tappet settings are 6thou runningclearance or 12 thou when setting up valve timing. Might even have a bit more torque than a seven although I have never seen figures quoted for pre war torque. bhp officially remained at 17 but I have always had a feeling that a good engine must poke out a bit more than that - but then the CA?CB Bradfords were only supposed to have 19bhp. I have always wondered just what the 1940 Eight managed as the only one I have ever been in when in my teens was far livelier than any other pre war twin I have come accross, running very easily and remarkably queitly at around 50mph.
george

AlanBartlett · Post by **AlanBartlett** » Fri Aug 10, 2007 10:02 pm

At present ive got the tappets at 2 thou? does this mean I have to change them back to 6 thou? blast oh well. you are definetly right about the torque though it certainly shifts I find, although I havent taken it out of first and reverse gear the torque I find is quite responsive.