rebuilt 1275 engine wont start

Post by **picky** » Tue Aug 14, 2007 4:24 pm

Hi there

Trying to start a 1275 midget engine out of the car, tied down on a pallet. Wont start! I suspect the camshaft timing might be out, as this was what tripped me up last time. Engine does turn over, I have a wire running from battery + to coil +, and wire from coil - to distributor. fuel in carb float chamber, using colourtune a spark is visible while engine turns over. How can I confirm camshaft is lined up properly? the timing gears dont have any marks on them as they are adjustable and the crank pulley has no timing mark either, which makes setting ignition timing difficult. (supercharger is not fitted at the moment)

Any ideas much appreciated!

Picky

Post by **Rob_Jennings** » Tue Aug 14, 2007 4:50 pm

err?

disconnect battery, rotate until top dead center (piston 1 at height of stroke) and adjust distributor for open points on spark one there? would that give a roughly correct static timing?

Post by **chickenjohn** » Tue Aug 14, 2007 4:52 pm

maybe you have the spark plugs in the right order but 1342 at the wrong time. Try moving them all around one and try to start again. Then move them along one again.

To check Cam shaft timing, I guess you could turn the engine over by hand, have a screwdriver poking out of spark plug 1 hole to determine TDC and go from there making sure the valves are opening /shut at the right time etc (rocker cover off). Then check the ignition timing compared to TDC. I have a midget manual at home (car not very small), i will have a look and possibly scan the timing instructions- if no-one comes to your help before.
cheers
John

Post by **Alec** » Tue Aug 14, 2007 5:36 pm

Hello Picky,

a simple camshaft timing check:- Remove the rocker cover, get the engine about TDC number one firing, number four cylinder valves should be rocking as you move the engine backwards and forwards about TDC. (i.e one closing the other opening.)
Rotate the engine until one of the valves of the number four cylinders is just closed, mark the damper using the TDC timing pointer. Rotate the engine in the opposite direction until the other valve is just closed and again mark the damper. If the timing is correct the two marks will be equal in distance from the TDC mark on the damper.
(Think of TDC as 12 o'clock, and closing points of the valves being ten to and ten past twelve, i.e symmetrical about TDC.)

Alec

Post by **bigginger** » Tue Aug 14, 2007 5:45 pm

Being stupid here - the damper?

Post by **Alec** » Tue Aug 14, 2007 6:18 pm

Hello Andrew,

sorry, just a habit, of course the Minor does not have a damper but a crankshaft pulley.

Alec

Post by **bigginger** » Tue Aug 14, 2007 6:21 pm

Right - I've got 1275s too, but still think of it as the crankshaft pulley

Post by **Alec** » Tue Aug 14, 2007 6:33 pm

Hello Andrew,

on most cars the pulley also has a rubber mounted 'damper' to reduce engine vibration.

Alec

Post by **bmcecosse** » Tue Aug 14, 2007 9:27 pm

ALL 1275 engines have the crank damper.
Unless you have made a complete mess of the cam timing - the engine should start. Alec's method for checking is excellent. Also just check the spark is happening on the cylinder that happens to be on compression - check with finger over spark plug hole - and then advance the ignition timing until you can feel it 'kicking' against the starter - then back it off slightly. It WILL start - you may just have flooded the plugs, although more likely is not enough fuel - try pouring an egg-cup full down the carb inlet - and crank it! Just take a little care in case a sheet of flame blows back out the carb inlet!!

Post by **picky** » Tue Aug 14, 2007 9:52 pm

thanks everyone for the replies,
the cam timing check that alec mentioned is what i was looking for, have heard it before somewhere. Will check all of the above and see what happens.

Then if its running ok I will bolt on the supercharger! which I imagine will introduce a new set of problems.. Wish me luck...

Picky

Post by **bmcecosse** » Tue Aug 14, 2007 9:55 pm

I really do think the scharger is going to be more trouble than it's worth - but good luck with it anyway!

Post by **picky** » Tue Aug 14, 2007 10:06 pm

I hope it works! spent alot of time and money on it.

Post by **Alec** » Tue Aug 14, 2007 10:10 pm

Hello Picky,

it should be interesting, it was a period modification albeit not a cheap one. The view then was that it was like putting in an engine 40 or 50 percent larger.

Alec

Post by **bmcecosse** » Tue Aug 14, 2007 10:17 pm

Aye - but that was quite low pressure charging - on low compression engine to start with! It is obviously still the way to go - look at the MINI Cooper S and Merc Kompressor.

Post by **picky** » Thu Aug 16, 2007 4:46 pm

Got it started after alot of head scratching - the kunurled nut to adjust ignition advance was turned as far as it would go, so the timing was miles out even though it looked like it was setup ok. Corroded jump leads didnt help either. Just spent the afternoon fitting the engine in the car, nearly ready for driving. Thanks for everyones input!

I will need it again when the supercharger is fitted...

Picky

Post by **1098** » Thu Aug 16, 2007 6:23 pm

Edited by RogerRust

nothing to do with this thread and of a personal nature.

1098 PM me if you have a problem with this action.

Post by **picky** » Thu Aug 16, 2007 7:32 pm

PM sent 1098.... sorry about the delay!!

Post by **bmcecosse** » Sat Aug 18, 2007 6:37 pm

Always best to set the knurled nut mid-stream when setting up ignition. Then you have some easy lee-way either side for adjustments. Well done getting it going!