Cylinder 4 is down. Thoughts very welcome and greatly appreciated. Thanks!

Cylinder 4 is down. Thoughts very welcome and greatly appreciated. Thanks!

Geoff from Aus
Geoff from Aus

March 12th, 2008, 2:47 am #1

Hi there Folks, I'm interested in getting peoples thoughts on a problem. I've been finding that i've been getting a fair bit of crankcase blow-by at idle which results in a poor idle with the factory setup of the vent connected to the air filter housing. I changed this setup and put a simple filter over the end of the pipe and she was running really really well. Gasses were being vented to the atmosphere under the bonnet so there was a little bit of smoke happening when sitting still in traffic but otherwise, the setup worked well.

After resolving a different problem with the carb setup, i decided to retry the crankcase breather connected to the airfilter housing factory setup. I leaned the carb idle mixture a half turn to try and compensate for the added richness of the blow-by gasses. Car started off ok but after 10kms of stop start traffic, the idle was getting slower and slower till it wouldn't idle at all - stopping at lights required the application of the accelerator to keep the car running.

Heading for home, i went up a really steep hill (1st gear, high revs) - this is where my problems really started. Other than my idle problem, the car started running on 3 cylinders. It was 12am so stopping to see what was going on wasnt really an option so i just drove it home on 3 cylinders. When i got home, i noticed that there was smoke coming from the engine bay. Inspection revealed oil dripping from the filter housing onto the exhaust. Pulling the lid off the housing revealed and oil pool up level with the top of the carbie. Great i thought - this is going to be a relatively easy fix. Hmmmm....

Mopped up the oil. Cleaned out the jets (though not the float bowl). Disconnected the breather hose and rigged up a different setup that didnt vent into the carb. Still running on 3 cylinders. Ran the car on 3 cylinders for 10 mins with no improvement. Plugs are fouled, i thought, and indeed they were a little bit sooty but not bad enough, i would have thought, to not run. Anyway, i cleaned up the plugs (all 4) with some wet n dry followed by a blow with pressurised air. I also checked the gaps for the plugs but they are pretty new and they were all fine. No joy - still running on 3.

Next i pulled the high tension leads off 1 by 1 (with the engine running) revealing cylinder 4 wasn't firing (the one closest the gearbox). All the other cylinders appeared to be working fine and removal of their respective leads led to the engine stopping. "Hmmm" i thought. I checked the lead for damage and it appeared fine - it's not all that old. I also did the earthing on the block check with the lead which revealed a good spark which travelled a maximum of probably 16-18mm.

Next i thought "well, perhaps it's just spark plug 4 that's cactus", so i threw 4 new plugs at the car just to be sure. No good. Still running on 3 cylinders.

Does anyone out there have any more ideas?

Other things to note:
Feebee is a 1978 X1/9
A previous compression check revealed all cylinders to be within the 130-139 range PRIOR to the oil saga - I havent check the compression POST saga.
Cam belt was replaced < 500kms ago - was running really well!
Points and timing is done by my mechanic, Mr Mal Ditchman <1500kms ago. Dizzy is from a 128 - has never been a problem in the past.
Cooling system appears fine - very little fluid loss evident
Car was running fine.
Oil was recently changed - ~3.9litres put in. Reads "full" on the dipstick.
Crankcase breather still has flame trap inserted
Plenty of blow by gas( white) comes out when idling but this less evident when the car is revved.
No blue smoke is evident from the exhaust
Car was running really well prior to oil saga

Thoughts appreciated!

Many thanks,
Geoff
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Joined: May 11th, 2007, 4:20 am

March 12th, 2008, 5:33 am #2

Geoff,
Are you using NGK plugs? I had one out of a new set of 4 that was crook, might have swapped in a newer problem. I had to resort to swapping them out one at a time with an old one. Is the problem still with No:4? Did you check the lead with a multimeter?
Dino.
Quote

htf
Joined: May 5th, 2001, 4:29 pm

March 12th, 2008, 6:05 am #3

Hi there Folks, I'm interested in getting peoples thoughts on a problem. I've been finding that i've been getting a fair bit of crankcase blow-by at idle which results in a poor idle with the factory setup of the vent connected to the air filter housing. I changed this setup and put a simple filter over the end of the pipe and she was running really really well. Gasses were being vented to the atmosphere under the bonnet so there was a little bit of smoke happening when sitting still in traffic but otherwise, the setup worked well.

After resolving a different problem with the carb setup, i decided to retry the crankcase breather connected to the airfilter housing factory setup. I leaned the carb idle mixture a half turn to try and compensate for the added richness of the blow-by gasses. Car started off ok but after 10kms of stop start traffic, the idle was getting slower and slower till it wouldn't idle at all - stopping at lights required the application of the accelerator to keep the car running.

Heading for home, i went up a really steep hill (1st gear, high revs) - this is where my problems really started. Other than my idle problem, the car started running on 3 cylinders. It was 12am so stopping to see what was going on wasnt really an option so i just drove it home on 3 cylinders. When i got home, i noticed that there was smoke coming from the engine bay. Inspection revealed oil dripping from the filter housing onto the exhaust. Pulling the lid off the housing revealed and oil pool up level with the top of the carbie. Great i thought - this is going to be a relatively easy fix. Hmmmm....

Mopped up the oil. Cleaned out the jets (though not the float bowl). Disconnected the breather hose and rigged up a different setup that didnt vent into the carb. Still running on 3 cylinders. Ran the car on 3 cylinders for 10 mins with no improvement. Plugs are fouled, i thought, and indeed they were a little bit sooty but not bad enough, i would have thought, to not run. Anyway, i cleaned up the plugs (all 4) with some wet n dry followed by a blow with pressurised air. I also checked the gaps for the plugs but they are pretty new and they were all fine. No joy - still running on 3.

Next i pulled the high tension leads off 1 by 1 (with the engine running) revealing cylinder 4 wasn't firing (the one closest the gearbox). All the other cylinders appeared to be working fine and removal of their respective leads led to the engine stopping. "Hmmm" i thought. I checked the lead for damage and it appeared fine - it's not all that old. I also did the earthing on the block check with the lead which revealed a good spark which travelled a maximum of probably 16-18mm.

Next i thought "well, perhaps it's just spark plug 4 that's cactus", so i threw 4 new plugs at the car just to be sure. No good. Still running on 3 cylinders.

Does anyone out there have any more ideas?

Other things to note:
Feebee is a 1978 X1/9
A previous compression check revealed all cylinders to be within the 130-139 range PRIOR to the oil saga - I havent check the compression POST saga.
Cam belt was replaced < 500kms ago - was running really well!
Points and timing is done by my mechanic, Mr Mal Ditchman <1500kms ago. Dizzy is from a 128 - has never been a problem in the past.
Cooling system appears fine - very little fluid loss evident
Car was running fine.
Oil was recently changed - ~3.9litres put in. Reads "full" on the dipstick.
Crankcase breather still has flame trap inserted
Plenty of blow by gas( white) comes out when idling but this less evident when the car is revved.
No blue smoke is evident from the exhaust
Car was running really well prior to oil saga

Thoughts appreciated!

Many thanks,
Geoff
I'm afraid you broke a piston ring or something like that.
I know you did it a while back, but do it again.


HaXD
Herzel, in Israel

WhiteX
The late Green '85 X1/9
Quote

Geoff from Aus
Geoff from Aus

March 12th, 2008, 6:18 am #4

Geoff,
Are you using NGK plugs? I had one out of a new set of 4 that was crook, might have swapped in a newer problem. I had to resort to swapping them out one at a time with an old one. Is the problem still with No:4? Did you check the lead with a multimeter?
Dino.
G'day Dino, nope, i haven't rechecked that it's cyl 4. Will do though. RE the leads, nope, havent checked them with a multimeter (yet). I assumed that it was ok given that it producing a spark 15-18mm in length when pulled off the plug and earthed onto the engine head (though i admit to being far far far from an expert in this stuff). What further information would some multimeter diagnostics tell me?

Thanks for the reply.
Regards
Geoff
Quote

Geoff from Aus
Geoff from Aus

March 12th, 2008, 6:20 am #5

I'm afraid you broke a piston ring or something like that.
I know you did it a while back, but do it again.


HaXD
Herzel, in Israel

WhiteX
The late Green '85 X1/9
Herzel,
Will do. Will let you know how i get on with it.
Thanks
Geoff
Quote

DARREN NZ
DARREN NZ

March 12th, 2008, 8:12 am #6

Hi there Folks, I'm interested in getting peoples thoughts on a problem. I've been finding that i've been getting a fair bit of crankcase blow-by at idle which results in a poor idle with the factory setup of the vent connected to the air filter housing. I changed this setup and put a simple filter over the end of the pipe and she was running really really well. Gasses were being vented to the atmosphere under the bonnet so there was a little bit of smoke happening when sitting still in traffic but otherwise, the setup worked well.

After resolving a different problem with the carb setup, i decided to retry the crankcase breather connected to the airfilter housing factory setup. I leaned the carb idle mixture a half turn to try and compensate for the added richness of the blow-by gasses. Car started off ok but after 10kms of stop start traffic, the idle was getting slower and slower till it wouldn't idle at all - stopping at lights required the application of the accelerator to keep the car running.

Heading for home, i went up a really steep hill (1st gear, high revs) - this is where my problems really started. Other than my idle problem, the car started running on 3 cylinders. It was 12am so stopping to see what was going on wasnt really an option so i just drove it home on 3 cylinders. When i got home, i noticed that there was smoke coming from the engine bay. Inspection revealed oil dripping from the filter housing onto the exhaust. Pulling the lid off the housing revealed and oil pool up level with the top of the carbie. Great i thought - this is going to be a relatively easy fix. Hmmmm....

Mopped up the oil. Cleaned out the jets (though not the float bowl). Disconnected the breather hose and rigged up a different setup that didnt vent into the carb. Still running on 3 cylinders. Ran the car on 3 cylinders for 10 mins with no improvement. Plugs are fouled, i thought, and indeed they were a little bit sooty but not bad enough, i would have thought, to not run. Anyway, i cleaned up the plugs (all 4) with some wet n dry followed by a blow with pressurised air. I also checked the gaps for the plugs but they are pretty new and they were all fine. No joy - still running on 3.

Next i pulled the high tension leads off 1 by 1 (with the engine running) revealing cylinder 4 wasn't firing (the one closest the gearbox). All the other cylinders appeared to be working fine and removal of their respective leads led to the engine stopping. "Hmmm" i thought. I checked the lead for damage and it appeared fine - it's not all that old. I also did the earthing on the block check with the lead which revealed a good spark which travelled a maximum of probably 16-18mm.

Next i thought "well, perhaps it's just spark plug 4 that's cactus", so i threw 4 new plugs at the car just to be sure. No good. Still running on 3 cylinders.

Does anyone out there have any more ideas?

Other things to note:
Feebee is a 1978 X1/9
A previous compression check revealed all cylinders to be within the 130-139 range PRIOR to the oil saga - I havent check the compression POST saga.
Cam belt was replaced < 500kms ago - was running really well!
Points and timing is done by my mechanic, Mr Mal Ditchman <1500kms ago. Dizzy is from a 128 - has never been a problem in the past.
Cooling system appears fine - very little fluid loss evident
Car was running fine.
Oil was recently changed - ~3.9litres put in. Reads "full" on the dipstick.
Crankcase breather still has flame trap inserted
Plenty of blow by gas( white) comes out when idling but this less evident when the car is revved.
No blue smoke is evident from the exhaust
Car was running really well prior to oil saga

Thoughts appreciated!

Many thanks,
Geoff
Mine was also No4 cylinder and what I found was that the engine only fired on three cylinders initially but when I moved (a small fraction off the connector) the No4 lead off the top of the plug she fired great.

I replaced the lead and the plug and didn't have a problem for quite some time. The next time it happened I found a wet plug.........replaced the plug and she is fine again. It just so happens I was using NGK plugs also.

Don't you just love these cars!!!!!!!!!!!!!!!!

Good luck

Darren NZ
Quote

Geoff from Aus
Geoff from Aus

March 12th, 2008, 8:47 am #7

Hi there Folks, I'm interested in getting peoples thoughts on a problem. I've been finding that i've been getting a fair bit of crankcase blow-by at idle which results in a poor idle with the factory setup of the vent connected to the air filter housing. I changed this setup and put a simple filter over the end of the pipe and she was running really really well. Gasses were being vented to the atmosphere under the bonnet so there was a little bit of smoke happening when sitting still in traffic but otherwise, the setup worked well.

After resolving a different problem with the carb setup, i decided to retry the crankcase breather connected to the airfilter housing factory setup. I leaned the carb idle mixture a half turn to try and compensate for the added richness of the blow-by gasses. Car started off ok but after 10kms of stop start traffic, the idle was getting slower and slower till it wouldn't idle at all - stopping at lights required the application of the accelerator to keep the car running.

Heading for home, i went up a really steep hill (1st gear, high revs) - this is where my problems really started. Other than my idle problem, the car started running on 3 cylinders. It was 12am so stopping to see what was going on wasnt really an option so i just drove it home on 3 cylinders. When i got home, i noticed that there was smoke coming from the engine bay. Inspection revealed oil dripping from the filter housing onto the exhaust. Pulling the lid off the housing revealed and oil pool up level with the top of the carbie. Great i thought - this is going to be a relatively easy fix. Hmmmm....

Mopped up the oil. Cleaned out the jets (though not the float bowl). Disconnected the breather hose and rigged up a different setup that didnt vent into the carb. Still running on 3 cylinders. Ran the car on 3 cylinders for 10 mins with no improvement. Plugs are fouled, i thought, and indeed they were a little bit sooty but not bad enough, i would have thought, to not run. Anyway, i cleaned up the plugs (all 4) with some wet n dry followed by a blow with pressurised air. I also checked the gaps for the plugs but they are pretty new and they were all fine. No joy - still running on 3.

Next i pulled the high tension leads off 1 by 1 (with the engine running) revealing cylinder 4 wasn't firing (the one closest the gearbox). All the other cylinders appeared to be working fine and removal of their respective leads led to the engine stopping. "Hmmm" i thought. I checked the lead for damage and it appeared fine - it's not all that old. I also did the earthing on the block check with the lead which revealed a good spark which travelled a maximum of probably 16-18mm.

Next i thought "well, perhaps it's just spark plug 4 that's cactus", so i threw 4 new plugs at the car just to be sure. No good. Still running on 3 cylinders.

Does anyone out there have any more ideas?

Other things to note:
Feebee is a 1978 X1/9
A previous compression check revealed all cylinders to be within the 130-139 range PRIOR to the oil saga - I havent check the compression POST saga.
Cam belt was replaced < 500kms ago - was running really well!
Points and timing is done by my mechanic, Mr Mal Ditchman <1500kms ago. Dizzy is from a 128 - has never been a problem in the past.
Cooling system appears fine - very little fluid loss evident
Car was running fine.
Oil was recently changed - ~3.9litres put in. Reads "full" on the dipstick.
Crankcase breather still has flame trap inserted
Plenty of blow by gas( white) comes out when idling but this less evident when the car is revved.
No blue smoke is evident from the exhaust
Car was running really well prior to oil saga

Thoughts appreciated!

Many thanks,
Geoff
Hi Folks, i measured Feebee's cylinder compression thisarvo. Results are for a dry compression test:

Cylinder 1 (closest cam belt): 115psi
Cylinder 2: 130psi
Cylinder 3: 120psi
Cylinder 4: 5psi

No prizes for guessing why she was running on 3 cyls.

What am i going to do next - at this stage, i'm not sure.

Keep well all,
Geoff
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Russell woodall
Russell woodall

March 12th, 2008, 9:15 am #8

Hi jeoff sounds like you hale from my part of the woods Brisbane. you may want to put some oil in that number 4 cylinder with an oil can and see if it improves compression when you put the com tester on it, if it doesn't it could be a dead valve.you may try some ATF down the carb while running the motor could be a stuck ring but boy be prepared for lots of white smoke.my cars number 4 is down to 90 psi at the moment still going strong.Russell.
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Joined: May 11th, 2007, 4:20 am

March 13th, 2008, 12:23 am #9

Hi Folks, i measured Feebee's cylinder compression thisarvo. Results are for a dry compression test:

Cylinder 1 (closest cam belt): 115psi
Cylinder 2: 130psi
Cylinder 3: 120psi
Cylinder 4: 5psi

No prizes for guessing why she was running on 3 cyls.

What am i going to do next - at this stage, i'm not sure.

Keep well all,
Geoff
G'Day Geoff,
Try again after squirting some oil in there, (not too much or you will wear it), if no change then could be a valve or gasket (look for oil in the water or water in your oil). I ended up burning an exhaust valve in my mini due to insufficient valve tappet clearance (looked like a 1/8th inch pie wedge had been removed)and weak carby mixture.
Another thing to remember with carbys, if you chop and change fuel supplies, especially with E10 you will need to richen your mixture by about 3% compared to fuel with no ethanol, the EFI in mine automatically compensates for all that.
Spark leads should measure between 2,000 and 7,000 ohms, more than 10,000 ohms bin them. Spark plugs that break down internally are not easy to test on the bench, best to swap one at a time in the engine with a known good one.
Dino.
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