Distributor drive shaft alignment

Reliant, Rialto, 850cc, Distributor, Distributer, Driveshaft, Positioning

I put these tags in above to help someone one day find this post in an internet search, and benefit from my learning process, and not have to learn the hard way..... as I did.

I have been using an old Haynes manual to help me rebuild the engine (its actually a Robin and Kitten 1973 - 1979 manual - I cant find a Rialto manual - but it does give a nod to the 845cc engine).  Its a pretty simple engine and there isn't much you can get wrong really, but nevertheless, I carefully followed the step by step reassembly instructions.  But I have to admit a bit of head scratching when it came to trying to understand the instruction for inserting the distributor / oil pump drive shaft.

Once the crank and the cam shaft are in place and positioned with the timing chain, its time to drop the distributor shaft in from the top of the engine to engage with the cam shaft..... this is what the manual tells you to do

I found this simple instruction rather ambiguous  (it becomes more so, as the shaft rotates as it drops into place - so are we talking about a position before or after it drops down?) - but I thought it through and made my interpretation of it.

A few weeks later, when the engine is all rebuilt, back in the frame, all wired up with a jury-rigged ignition circuit - I tried to start her. No joy :-(  After a couple of nights tossing and turning, it occurred to me that maybe my distributor was firing at the wrong moment - there was yards of spark at the plug, and plenty of fuel in the cylinder.  So I decided to see if I could 'reinterpret' and reposition the distributor drive shaft - this involved jacking the trike up, dropping the sump (complete with oil) removing the oil pump and driving the roll pin out of the shaft retaining collar (or as Haynes likes to call it, the "Thrust Muff" which sounds a bit saucy to me)

I reassembled it all again - tried to start her...... Still, No joy :-(

Finally, this weekend, I was determined to get this sorted.  I methodically went through everything, and still she wouldn't start.  Hugh came over and we scratched our heads together... then my neighbour came over and we all three scratched and shook our heads - we are becoming Umarells (and i rather like it)

My neighbour looked at the manual, and said "but what about if you were standing looking at the engine from the front? then '5 past 7' would be in a different position" He was right!  '5 past 7' could be anywhere depending on where you looked at it - I had assumed it was from the side of the engine.

We played with this idea.... but still weren't completely convinced about where the 'large D section' was going to end up.  The sun was shining, it was mid afternoon, and I needed a beer - so I gave up for the day and planned to go the following day to see a man who might know the answer.

Reliant Services are great.  Not particularly cheap, but full of knowledge and advice (and you cant put a price on that) - I took my manual with me, and asked Jim to tell me how to interpret the instructions.

"I dont do it like that" he said...... so I asked him to explain his method..... So, for those people who are new to assembling a reliant engine, here is the clear and simple method for getting the distributer shaft in the right position, first time ......

1. Rocker cover off
2. Rotate engine until BOTH tappet rods - of cylinder No.1 (thats at the fan end of the engine) can be 'twizzled' (this indicates TDC/compression stroke) - personally I simply put my finger over the sparkplug hole and feel when compression is happening.... but I like the 'twizzle' method better)
3. Make sure the timing mark (on the timing chain cover) lines up with the 2nd notch (for 850cc engines) on the pulley
4. Drop the distributer shaft into position so that when the distributer is in place, the rotor arm points to cylinder No.1

Simple as that - forget about big D's and little D's - I'm sure these are good references when you know what you are doing, but the bottom line check is to put the distributer loosely into place and see if the rotor arm points to No.1... if it doesn't, withdraw the shaft and move it round until it does.  And when it does, then you can fix it in place with the roll pin and 'muff'

So I came home, and within 2 hours (jack up, sump off, pump out, muff removed - reposition shaft - muff back, pump back, sump back.... distributer in, leads on)..... I tried to start her again.

Joy :-D

Nearly 7 years since she last ran..... she came to life :-)  Oh boy, that is a good feeling :-)