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eagle3
Alfa 33
Joined: 11 Nov 2007
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Location: France
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 Posted: Thu Sep 19, 2013 9:39 am Post subject: |
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In that case I would have expected an anomolie in cylinder 1 as well...
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Alfa33 QO 1984
Alfa33 1.3i.e. 1994 |
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Brit01
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| Posted: Thu Sep 19, 2013 3:15 pm Post subject: |
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| eagle3 wrote: |
| In that case I would have expected an anomolie in cylinder 1 as well... |
not sure what you mean.
if there is a valve issue you would expect some issues with the opposite cylinder #1?
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S2 33 1988 1.7 QV
Dellorto DRLA40 (32mm venturi) |
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Brit01
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| Posted: Thu Sep 19, 2013 5:38 pm Post subject: |
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ah I started talking about oil and he mentioned he only uses Castrol now. For his street and race cars.
Which one??
TWS 10w60!!! (jaja I mentioned 300v and he frowned and said 'French oil no thanks!' lol)
I had just changed from Castrol 10w60 to 300v!
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kevjtd
Alfa Arna
Joined: 13 Sep 2013
Posts: 22
Location: Lincolnshire
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| Posted: Thu Sep 19, 2013 11:42 pm Post subject: |
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so, what was the problem then?
thought you had compression down on just one cylinder 
dodgey cambelt tensioners wouldn't cause that, not on just one pot anyway |
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Brit01
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| Posted: Thu Sep 19, 2013 11:59 pm Post subject: |
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| kevjtd wrote: |
so, what was the problem then?
thought you had compression down on just one cylinder
dodgey cambelt tensioners wouldn't cause that, not on just one pot anyway |
We don't know for sure.
All we know it lost compression for some time and then burst back to life and runs sweet now.
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eagle3
Alfa 33
Joined: 11 Nov 2007
Posts: 402
Location: France
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| Posted: Fri Sep 20, 2013 12:47 pm Post subject: |
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| Brit01 wrote: |
| eagle3 wrote: |
| In that case I would have expected an anomolie in cylinder 1 as well... |
not sure what you mean.
if there is a valve issue you would expect some issues with the opposite cylinder #1? |
If the camshaft is out of sync due to a faulty tensioner, both cylinders controlled by that camshaft would be affected logically.
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Brit01
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| Posted: Fri Sep 20, 2013 2:05 pm Post subject: |
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| eagle3 wrote: |
| Brit01 wrote: |
| eagle3 wrote: |
| In that case I would have expected an anomolie in cylinder 1 as well... |
not sure what you mean.
if there is a valve issue you would expect some issues with the opposite cylinder #1? |
If the camshaft is out of sync due to a faulty tensioner, both cylinders controlled by that camshaft would be affected logically. |
ok I see were you were coming from
all timing was perfect. one of the second things i checked. thought it may have jumped a tooth.
well valves appear to be working fine now.
and peace of mind I have new tensioners now.
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kevjtd
Alfa Arna
Joined: 13 Sep 2013
Posts: 22
Location: Lincolnshire
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| Posted: Mon Sep 23, 2013 8:16 pm Post subject: |
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| Brit01 wrote: |
| eagle3 wrote: |
| Brit01 wrote: |
| eagle3 wrote: |
| In that case I would have expected an anomolie in cylinder 1 as well... |
not sure what you mean.
if there is a valve issue you would expect some issues with the opposite cylinder #1? |
If the camshaft is out of sync due to a faulty tensioner, both cylinders controlled by that camshaft would be affected logically. |
ok I see were you were coming from
all timing was perfect. one of the second things i checked. thought it may have jumped a tooth.
well valves appear to be working fine now.
and peace of mind I have new tensioners now. |
still makes no sense at all to me.
if the problem was the tensioners then that would affect the cam timing on both those cylinders on that bank. as eagle3 has said.
if also all of a sudden you have compression without stripping/finding a fault it is more than likely to return. maybe without getting away with it next time if you have a sticking valve...
what were the ingredients for it to lapse onto 3 cylinders, with NO compression on one pot?
was it straight after a hard run?
overheating?
overrev?
i'd be looking at stripping the head at the very least, see if there's evidence of sticking valves/broken valve guides/hydraulic tappet issues. |
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Brit01
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| Posted: Mon Sep 23, 2013 9:04 pm Post subject: |
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[quote="kevjtd"]
| Brit01 wrote: |
| eagle3 wrote: |
| Brit01 wrote: |
| eagle3 wrote: |
| In that case I would have expected an anomolie in cylinder 1 as well... |
not sure what you mean.
if there is a valve issue you would expect some issues with the opposite cylinder #1? |
If the camshaft is out of sync due to a faulty tensioner, both cylinders controlled by that camshaft would be affected logically. |
ok I see were you were coming from
all timing was perfect. one of the second things i checked. thought it may have jumped a tooth.
well valves appear to be working fine now.
and peace of mind I have new tensioners now. |
Tensioners was a different issue and yes nothing to do with the compression loss.
I did do an oil change a week or so before it occurred.
I imagine if anything broke then it would have been permanent.
Very strange as it is running perfectly now. Only if it occurs again we'll remove the head.
Not much point in removing it now as it all works fine. No noises. No oil loss. No tappet noises.
Smooth quiet and just fine.
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eagle3
Alfa 33
Joined: 11 Nov 2007
Posts: 402
Location: France
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| Posted: Mon Sep 23, 2013 9:36 pm Post subject: |
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| Quote: |
| Tensioners was a different issue and yes nothing to do with the compression loss. |
I don't follow you. You change the timing belts and tensioners and now everything's fine.
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kevjtd
Alfa Arna
Joined: 13 Sep 2013
Posts: 22
Location: Lincolnshire
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| Posted: Mon Sep 23, 2013 9:53 pm Post subject: |
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Tensioners was a different issue and yes nothing to do with the compression loss.
I did do an oil change a week or so before it occurred.
I imagine if anything broke then it would have been permanent.
Very strange as it is running perfectly now. Only if it occurs again we'll remove the head.
Not much point in removing it now as it all works fine. No noises. No oil loss. No tappet noises.
Smooth quiet and just fine.[/quote]
i'd be worried about waiting for it to happen again, especially if it was a sticking valve.
they don't like sticking open and being rammed by a piston.
just because it's not doing it now doesn't mean it's cured!
if the valve stem has a burr or damage, same for the valve guide, then once the same heat situation is replicated then they could well stick again.
like a 2 stroke engine heat siezing
how do you know for sure that the valve seat didn't dislodge?
sorry but it just doesn't add up for me.
are you saying that you had no (as in ZERO) compression on the one cylinder and then it just cured itself?
rather than wait for a bomb to go off i'd want to de-fuse it |
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Brit01
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| Posted: Mon Sep 23, 2013 10:13 pm Post subject: |
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| eagle3 wrote: |
| Quote: |
| Tensioners was a different issue and yes nothing to do with the compression loss. |
I don't follow you. You change the timing belts and tensioners and now everything's fine. |
no mate.
issue #1 : squeaky timing belt tensioners. was due to go in for a change
issue #2: lost compression on cylinder #2
we're on issue #2 
it just happened to resolve itself while the car was in the workshop. he started up the car to move it around in the garage to take its head off and it starting running smoothly again.
so it stayed in the garage for him to work on the tensioners.
hope that clears up the confusion
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Brit01
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| Posted: Tue Sep 24, 2013 3:50 pm Post subject: |
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Incidentally just a short time before this compression loss occurred I did have a long trip where I was stuck in traffic for about 1.5 hours, with the car idling, stopping and starting for this entire time.
An awful lot of idling which these cars do not like too much.
Temp was controlled well with the fans but still maybe a build up of gunge or carbon on the valves/guides that cleared itself now?
Just a thought.
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