Clutch problems?

[ChrisBeardy]

Hello,
This is my first post on this forum but certainly not my first problem, so I'd like to thank everybody who has helped me in the past without knowing it. I can't find a thread pertaining to my current problem. So...

The car had been running well until I a few weeks ago. I was driving along in 2nd gear and when I tried to move up to 3rd I couldn't get into gear. I slowed and went back into second, and there didn't seem to be as much power as before. I then pulled up to a red light. When I tried to pull away again I could easily select 1st but no power was transmitted. The engine was revving but when I released the clutch the engine stalled. This happened 2 or 3 times before I had to give in and push the car to the side of the road. I've now towed it back to the house and the problem persists. Any ideas what the problem is?

Many thanks in advance

[MarkyB]

If it was just no power being transmitted I'd suggest a busted half shaft, but from the rest of your description it sounds more like something has gone wrong inside the gearbox.

Can you select gears without the engine turning?
Does the gear lever action feel normal?

[bmcecosse]

If it's just 'no power' then perhaps the engine has failed in some way? Does it sound ok - smooth/no spluttering ?? Or as others have said - a half shaft may have broken - does the speedo needle shoot up if you put it in gear and let the clutch out? Or - it could be clutch plate failed. So -let's hear more details.....

[ChrisBeardy]

Ok.. I had a look when I got back from work today. I tried selecting the gears without the engine turning and I had problems selecting 3rd and reverse otherwise it seemed ok. I then thought I'd try it again with the engine turning and it was fine. No stalling. I still had difficulty getting into 3rd gear but it did and drove around fine. I then checked the free movement in the clutch pedaland it was about 3 1/2 inches. I feel a bit stupid really. I probably should have checked this a few weeks ago. I adjusted it to 1 1/2 and it was finding 3rd and reverse much more easily. And still driving around fine. Could this have been causing the original problem?
The engine is running quite smoothly. I guess it could be called a little lumpy. There is an occassional what I would describe as a 'phwump' noise with a simultaneous puff of smoke from the exhaust.
A couple of weeks before the stalling I had taken the head off, and replaced the exhaust valves, two of which had disintergrated completely, and the valves, springs etc. I adjusted the valve gaps and timing and then took it to a mechanic to check. He thought it was running fine.
This is the first car I've worked on. I took some evening classes in car maintenance but my knowledge is patchy at best. So I apologise if my questions are a bit basic. Thank you both for your help.

[MarkyB]

It sounds like you are doing great work .
I trust that you ground the new valves in and cut the seats if needed?
As the engine has been through some heat cycles you should recheck the torque setting of the head bolts then recheck the valve clearances.

[bmcecosse]

That phwump sounds a bit worrying..... As above - retorque the head now and set the gaps - 12 thou inlets and 15 thou exhausts.......

[ChrisBeardy]

Thanks Mark. I certainly did grind the valves in! I remember it well.
Yes I did retorque the head and check valve clearances a couple of weeks after fitting it. All the nuts were still torqued correctly. Hmmm... the phwump is a bit worrying, but it seems to be driving fine. I'll have another look today. It is burning a bit of oil.

What is meant by a 'heat cycle'? I noticed a lot of people recommended checking head torque after 4 heat cycles.

[bmcecosse]

1 heat cycle - in other words - run the engine till hot, let it cool and then retorque.......

[MarkyB]

Try a compression test, maybe the mechanic can lend you a gauge?
Did the new valves slide in without resistance? I'm wondering if the phwump is caused by a valve sticking.