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Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 14:00
by davethebus
Advice needed, swapped distributors from points to electronic as it was suffering a bad misfire then wouldn't start again. Fitted the new dizzy and it coughed a bit then went back to non starting.
I've checked for spark and all is ok, stripped and rebuilt carbs then a gut feeling told me to take the rocker covers off.
Tappets aren't moving at all. No nasty noises or anything like that, it's like the hydraulic tappets aren't moving at all.
Looking like this was the problem to start with, maybe oil pump??

Any advice gladly received, very close to selling it. Only managed one trip without hassle last year :(

Re: Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 15:44
by kevtherev
has the rocker shaft come off it's mountings on both sides!!?
The lifters will still move the valves with no oil in them

Re: Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 16:28
by PetenAli
kevtherev wrote:has the rocker shaft come off it's mountings on both sides!!?
The lifters will still move the valves with no oil in them

Or, similar principle to what Kev suggests, have the adjusters come loose, de-adjusted and are now not pushing down on the valves when the push rods come up on the cam?

Re: Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 16:58
by davethebus
Had a quick look and they look in situ.

On closer inspection they do seem to be moving but not by much at all, hardly noticeable. Will have a better look tomorrow.

Re: Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 19:35
by BOXY
If you've swapped a 009 dizzie for the standard one you need to time the engine statically first. The position for the timing mark on the rim is different between the two dizzies from what I remember. Just because you're getting a spark doesn't mean it's firing at the right time or even on the right cylinder. Make sure you've got the timing right first before you start pissing about with anything else.

Re: Valves not opening, Aircooled cu

Posted: 30 Jan 2014, 20:02
by davethebus
BOXY wrote:If you've swapped a 009 dizzie for the standard one you need to time the engine statically first. The position for the timing mark on the rim is different between the two dizzies from what I remember. Just because you're getting a spark doesn't mean it's firing at the right time or even on the right cylinder. Make sure you've got the timing right first before you start pissing about with anything else.

I did that first but will double check its correct in the morning.

Re: Valves not opening, Aircooled cu

Posted: 31 Jan 2014, 19:05
by davethebus
Ok, today I checked everything I had done and still no luck apart from spluttering like it wanted to start.

Stripped and cleaned both carbs and tried again, managed to get it running by holding it at half throttle.

Manually opened the chokes on both carbs as I had a sneaky feeling they were an issue and it struck up straight away and purred a treat.

Next question is how do I set the chokes up correctly on solex twin carbs?