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Discussion Starter #1
I purchased an 07 Turbo 6sp as a project car for my son and I to work on. It was suspected of having a faulty timing chain and had not run in 2 years so we paid a fairly low price for it. Once we hade the valve cover off we determined that the timing chain was not in bad shape so a compression test showed no compression in cyls 3 & 4. We removed the head and found that the head gasket had "burnt" through at the top of the cylinders 3 & 4 (at the narrowest point) which was obviously creating no compression in those cylinders.
Took the head to an engine shop and they flattened the head and replaced all of the valves, seals, etc. Seemed like this would resolve all of our engine issues.
Once assembled and timing correctly lined up (or so we think) the engine would turn over and fire occasionally but would not run. After pulling out our hair on this one, we did another compression test and discovered no compression in Cylinder 4. Head is off again and the valves look ok to me but I will take to a shop to confirm.

My question, In using the crankshaft locking tool we were able to confirm that the cylinders were all lined up straight across (put straight wire in the spark plug holes as an indicator) while setting the camshafts. Is there more than one locking hole in the flywheel and did we have the crankshaft off by 180deg, etc while doing the timing. I see conflicting info on the web but it seems to me that there would be exactly 2 points in the crankshaft rotation where the cylinders would be all lined straight across at about halfway through the rotation.

Thanks
 

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Hi,

I bought exactly the same car with the same issue last year as a none-runner. In my case the timing chain had been incorrectly replaced. In that the bottom pulley bolt, being a stretch bolt (as are the bolts in the ends of the camshafts) should have been replaced and hadn't. This meant that the crank cog was slipping and the bottom end was rotating and the top end wasn't. Cue loads of bent valves and I ended up putting a different head on it.

I found putting the flywheel pin in to be a bit of a pain. On mine there seemed to be a bit of a raised flange around the hole, This meant that the pin would feel as though it had gone in and locked as you couldn't rotate the engine clockwise with the pin being hard against this projection.
If I had set the timing then, then it would have been a few degrees out. The trick to see if the pin in in place is to see if you can turn it anti-clockwise. With the pin in place right in the hole, this should not be possible.

In my case, to set it, I had to ease the pin back out again, very slightly rotate and then the pin would slide in past this flange/collar projection.

Although it's possible to get false positives locating the pin hole with the pin correctly in place, there should be writing stamped on the camshafts both pointing straight up at 12 oclock.

As an aside I remember an earlier thread where somebody had issues with this process and then discovered that their flywheel had been replaced and was 180 degrees out. Hopefully that won't be the case!!
 

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there is only one lock hole in flywheel and flywheel bolts located in such a way that wont fit unless at correct point on crank shaft,, i've seen a few mistakes made by people over the years most common is thinking crank pin is in correct place when its not ie its possible to catch a point on flywheel where it will lock in one direction hence why always when lock crack try and turn it both ways to make sure
 

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Discussion Starter #4
Thank you
I have confirmed that the locking pin is completely in the hole.
Shop has confirmed that the cylinder head and valves are ok and none are bent. They did a suction test on each valve.

My question is: If there is only 1 way to lock the pistons in place (which is with all of them horizontal and pin engaged in the flywheel) why would cylinder 4 NOT have had compression? If the timing was off, then that would explain no compression but I truly am stumped.
 

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1badR56
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Cams make one full rev for every two crank revs, therefore the crank can be locked 180* out. Also the pistons will all be the same height four times --- two going the wrong direction, so using the cam markings / lobe "pointing" is critical when setting timing.

As for your cyl #4 compression, if the head is still on, try a "wet" compression test --- oil in the cylinder to seal ring leaks. Good chance rings are shot. What were the readings on 1 - 3? 160 - 180PSI is typical.
 

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Discussion Starter #6
Thank you for the reply. oldbrokenwind
I will try with some oil in the piston rings and post the results.
 

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Discussion Starter #7
I just put 20ml of oil in cyl #4 and got 30 psi when cranking. Other cylinders are giving 120 psi with no oil added.
Thank you for the suggestion @oldbrokenwind
I have confirmed that the timing has been done correctly so I will now proceed with putting the engine pieces back on (HP fuel pump, exhaust manifold, etc.
Will post updates shortly as things progress.
 

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Discussion Starter #8
Engine is assembled and I have confirmed to the best of my ability that everything is in good order.
Car will not start. It will turn over but not fire or run on its own for very long. Here is what I have observed:
  • Engine turns over but will not run. It seems like 1 cylinder is "trying" to run but if it runs at all it is at a very low RPM and it eventually stalls.
  • I have disconnected the exhaust after the downpipe to ensure the exhaust is not blocked. (car was sitting for a couple of years prior to me acquiring it so some small animals may have moved in)
  • I can confirm that the HP Fuel pump is getting fuel because I cranked the engine a few times and fuel shot out of the supply line from the tank.
  • I do not know if the HP fuel pump is working. When I bought the car there was no HP fuel pump installed but the seller gave me 2 pumps in a box. Apparently, while the car was sitting the seller swapped a working pump from my car and took back a non-working pump from another car of the same year. The seller then contacted a salvage yard to buy a replacement for my car. The salvage yard bent one of the flanges on the salvaged part while removing it and I had to swap flanges between the non-working pump and the salvaged pump. The salvaged pump is installed on my car. Note: I had to do some minor grinding on one of the pumps to swap flanges - so I'm not even sure the pumps are from identical years. Fuel pumps could be my problem.
  • Is there a way to test the fuel pumps or will they throw any error codes with the OBDC, etc?
  • I'm reluctant to go out and purchase a new HP Fuel pump without knowing that is my problem.
Thanks for reading this far.
 
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