Starting and gearchange

[Dippydog]

Whether or not these two issues are related I don't know although I don't see how,but any ideas/pointers greatly appreciated.The car is a Y reg C70 2.4 lpt manual petrol.
Starting: When trying to start the car it will very rarely start straight away but most of the time it turns over for a long time during which the rev counter will flick/bounce up to indicating anything up to 2000 revs before instantly dropping back to zero then repeating.I tried taking out the crank sensor and cleaning the end which appeared to cure it but only for three or four starts then it went back to awkward starting.So a new[cheap aftermarket]sensor was bought/installed just to try and prove sensor fault one way or the other which again "cured" the issue for three or four starts then back to awkward starting.Bit the bullet and bought a new Denso sensor and installed that but the issue remains.I can't see all three sensors being faulty.When the car eventually does start the tickover is smooth and steady and it revs cleanly with no hesitation throughout the rev range.
The gear change is very obstructive with gears[particularly first and reverse]being awkward to engage.I must say at this point the gear box is a second hand unit from an earlier car[I understand it's from an 850 but could be wrong on that]It could be that the concentric slave cylinder has not been fully bled and I'm going to give that a try soon,other than that are the gear change cable adjustable and if so where or have we bought a dodgy used 'box? Any ideas on either or both these issues greatly appreciated as we're trying to make this car the car it should be after it's been very poorly treated by previous owners. Sorry for long post.

[Baffler]

Originally Posted by Dippydog

When trying to start the car it will very rarely start straight away but most of the time it turns over for a long time during which the rev counter will flick/bounce up to indicating anything up to 2000 revs before instantly dropping back to zero then repeating.I tried taking out the crank sensor and cleaning the end which appeared to cure it but only for three or four starts then it went back to awkward starting.So a new[cheap aftermarket]sensor was bought/installed just to try and prove sensor fault one way or the other which again "cured" the issue for three or four starts then back to awkward starting.Bit the bullet and bought a new Denso sensor and installed that but the issue remains.I can't see all three sensors being faulty.When the car eventually does start the tickover is smooth and steady and it revs cleanly with no hesitation throughout the rev range.

Have you tried cleaning the connections of the antenna ring around the ignition?

Originally Posted by Dippydog

The gear change is very obstructive with gears[particularly first and reverse]being awkward to engage.I must say at this point the gear box is a second hand unit from an earlier car[I understand it's from an 850 but could be wrong on that]It could be that the concentric slave cylinder has not been fully bled and I'm going to give that a try soon,other than that are the gear change cable adjustable and if so where or have we bought a dodgy used 'box? Any ideas on either or both these issues greatly appreciated as we're trying to make this car the car it should be after it's been very poorly treated by previous owners. Sorry for long post.

That is/was a common complaint with the M56. If you don't see an improvement after bleeding the slave try carry out an oil change using the correct Volvo synthetic oil. It holds 2.1 litres so buy 2 litres and top up with 100ml off the old oil.

To the best of my knowledge there is no adjustment on the cables.

[ITSv40]

Regarding the gearchange I echo bafflers comments.

When I bought my C70, M56 manual, 50,000miles and full Volvo history, all gearchanges were like a hot knife through butter - when the car was in regular use. If it was parked up in the garage for 2 - 3 weeks reverse was very difficult to engage. Once warmed up all gear changes were back to smooth operation.

I changed the oil and the gearchange was transformed. Now the car can stand for several weeks and although reverse can be a bit notchy sometimes, generally reverse is easy to select. Only reverse has been difficult and only when the car has been standing.

Attachment shows the original oil and the new Volvo oil.

[Dippydog]

Firstly thank you chaps for your replies,it is much appreciated.Now a little more information which may or may not be relevant as the starting/gear change issues started well before this information.On Saturday I took up a gallon of fuel as I knew it was getting low and didn't want her panicking and diving into nearest petrol station with a low battery.As the car had not turned a wheel since January I told her the next time she used it to take it on a good run to possibly free up anything which may be sticking and get it properly warmed through and also to put some decent charge in the battery.Anyway she took it for a run Yesterday[Sunday]of about 20 miles,unfortunately she didn't tell me how it started from cold but at the end of the run she stopped at a supermarket and when she came out it started instantly but the EML stayed onon getting home[about two and a half miles]she turned it off and tried starting it again which took three attempts and EML stayed lit.I'll try a code read to see if I can find anything out.I'll certainly try cleaning antenna ring contacts.Gearbox oil was new when gearbox was swapped but can try a change if bleeding clutch doesn't work.

[Dippydog]

Got round to having a look at these issues today.First off I put a basic code reader on it which came up with P0014 which is cam timing advanced.Googling this it suggests an oil and filter change and/or cleaning or replacement of the camshaft oil control valve.However the car exhibits none of the symptoms they suggest[erratic idle/smoke from exhaust/poor performance/stalling]as previously said the engine will turn over with the rev counter sometimes flicking up the rev range before dropping back to zero and occasionally the engine will "lurch" as though one or more cylinders are flooded before continuing to spin over.The oil on the dipstick looks clean.I don't want to fire the parts cannon at this a step daughter can't at present afford this approach and I can't afford to lend her the cash.Once the engine starts the tick over is nice and even and steady it will spin through the rev range without issue and driving it the performance is as it has always been with no hesitation/misfiring or anything.
As for the gearchange with the engine off I could with effort get it into second third fourth and reverse bleeding the clutch made all gears available although notchy with the engine off.However starting the engine makes first difficult to engage and the other forward gears notchy to get but reverse all but impossible to select!
So any ideas where we go next with the error code and gearselection?