Hi I recently had the engine out of my 500 L (650cc) and now it will not start. I have stripped and cleaned the carb, made sure fuel being delivered. Checked spark with test light from negative on coil to earth and it goes out at the 10 deg mark on the pully . Checked spark at the plugs thats ok . I took the engine out to renew pushrod tubes as I was getting fumes in the cabin. While it was out I changed the oil and cleaned the filter. It will not fire at all even with easy start. I have checked to make sure by looking at the rockers that it is on the compression stroke on the outer cylinder and that I have suction on carb. Any ideas anyone ? Bryan
General Problem starting after engine out
- Thread starter phoenix1
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General Problem starting after engine out
the hobbler
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I have, to a greater or lesser degree, suffered this problem every time i have had the engine out of my 500---a tuned 650 '126'engine. I have discovered that the pump is very reluctant to suck fuel through from the tank. My son 'dumped' an old electric air-pump on me as it had stopped pumping much above 30psi. Perfect for me as I only require 25psi (for the rear tyres). I have found that by using the pump to pressurise the fuel tank (pipe into tank and 'seal' with some rag) I can force fuel through to the pump. The engine then normally starts no problem.
It is a long time since I had to 'statically' time my engine (it has electronic ignition), so correct me if I have got it wrong--but isn't the point of ignition when the test light comes ON?
It is a long time since I had to 'statically' time my engine (it has electronic ignition), so correct me if I have got it wrong--but isn't the point of ignition when the test light comes ON?
Hi Bryan, you've done everything by the book there; the 126 pump easily draws fuel from the tank if you give it sufficient engine turns as you have found out. With the engine at 10 BTDC you're correct in turning the distributor anti-clockwise until the points just open and the test-light goes out.
You've correctly checked that cylinder No1 is at the firing point.
Are you certain that everything lines up? At the 10 degree point the rotor arm should be pointing exactly at a distributor-cap electrode and that should carry the HT lead for whichever piston is on the firing stroke. Sometimes you may have to ignore the embossed 1 and 2 markings on the cap. I would try swapping the leads over if you're a bit uncertain on this. But if you're sure it's right, try turning the distributor a few degrees one way and the other and see if it fires up.
It will be something simple...it always is.
...bugger...you've lost me now.
But it does sound like a spark at the wrong time.:bang:
Yes I did have the dizzy out but it is firing at 10 deg before correctly . I.E. put the bulb out when connected to negative on coil to earth . it is on standard coil supplied with electronic ignition.I will have another bash today Wednesday I have all the time in the world at the moment .
the hobbler
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I was under the impression that you can only set 'static' timing with a test lamp when 'points' are fitted. With electronic ignition you have to use a timing-light (stoboscope) when the engine is running.
I realise that this is bit of "shutting the stable door after the horse has left", but I always set the engine at TDC, make a note where the rotor-arm is pointing AND use a centre-punch to (lightly!) mark both the distributor and the crankcase to give me an alignment reference point for when I out it all back together. This usually works
I realise that this is bit of "shutting the stable door after the horse has left", but I always set the engine at TDC, make a note where the rotor-arm is pointing AND use a centre-punch to (lightly!) mark both the distributor and the crankcase to give me an alignment reference point for when I out it all back together. This usually works
No, you can connect a test lead to negative side of coil to earth. It will light because until the ignition fires at 10 deg before it will be positive . When ignition fires it turns to negative to energise the coil (for split second).You can also move the dizzy to give you the best position for the ignition leads so they are not touching the exhaust .
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That's the Catch-22 with Lockdown and good weather....all the other
the hobbler
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Thank you Bryan---I have learnt something new (re how to use a test-light for timing with electronic ignition)
When the mark on the pulley is aligned with the fixed mark on the timing cover, that's 0 degrees not 10 degrees.
For setting the timing at 10 degrees before top dead centre, the pulley mark needs to be 13mm (iirc) to the left (i.e. anti-clockwise) of the fixed mark on the timing cover.
Al.
For setting the timing at 10 degrees before top dead centre, the pulley mark needs to be 13mm (iirc) to the left (i.e. anti-clockwise) of the fixed mark on the timing cover.
Al.
I am still working outside but tomorrow free so I will have another go . Just to mention I ordered some plugs today from Euro Parts Bosch equivalent (WR68C part number 408771350).If you order on line you get a big discount mine cost £5.55 with delivery for 4. Had not got the heart to just order 2 .
