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Technical Cam shaft replacement - is it an engine out job?

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Technical Cam shaft replacement - is it an engine out job?

smart51 said:
The RAC man suggested tapping the head to M14 x 1.25 and fit a larger spark plug, rather than have an M12 x 1.25 helicoil fitted. What would you do?
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I would have it brought back to the correct specification of 12 x 1.25mm thread. Obtaining 14mm plugs can be a bit of a pain---they are not very common in the automobile world. Have you got an engineering company near you who could fit an insert rather than helicoil?
 
the hobbler said:
I would have it brought back to the correct specification of 12 x 1.25mm thread. Obtaining 14mm plugs can be a bit of a pain---they are not very common in the automobile world. Have you got an engineering company near you who could fit an insert rather than helicoil?
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An insert? Bore it out big and press fit a piece with the correct thread?

There is a place nearby that 'does cylinder heads' though I'm not sure what they do. I could ask.
 
The original spark plugs in a 500 have an M14 x 1.25 thread so if you have a repair set to fit that size thread you should be OK.
 
Toshi 975 said:
The original spark plugs in a 500 have an M14 x 1.25 thread so if you have a repair set to fit that size thread you should be OK.
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My apologies--got my measurements "arse about face"---thank you for correcting me 'Toshi'. Whatever the measurement, I still think that you should go back to 'standard'
 
Just for clarification, I've found my digital calipers and measured the spark plugs. They are in fact M14 x 1.25.

The head is off again. The threads are stripped almost smooth. The helicoil kit I have bought is junk and I don't fancy a punt on another one. Can anyone recommend somewhere in the Birmingham area for a bit of cylinder head work?
 
One cylinder head with professionally fitted inserts. Now I just need to wait for the new head gasket.

20240308_101834.jpg
 
Aagh! I've dropped a bolt into the open fan housing. Is there an easy way of opening it at the bottom to retrieve the bolt?
 
smart51 said:
Aagh! I've dropped a bolt into the open fan housing. Is there an easy way of opening it at the bottom to retrieve the bolt?
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Yes (from practice!)----undo the bottom fan-shroud bolts (the ones that hold the 2 halves of the shroud together) and gently prise the 2 halves of the housing apart. If the bolt has gone all the way to the bottom of the fan shroud, it should drop through the slot you will create.
 
Engine rebuilt and run until it was warm. All seems to be well. I'll let it cool then check all the nuts and bolts for tightness.
 
Not good. A longer test drive and it started to make white smoke. The thermostat cover and much of the engine bay is covered in oil. At the first dim flicker of the oil pressure light, I've ditched the car an am walking to a petrol station to get some oil. 3.3 miles home from here when topped up. What are the likely causes of oil here?

20240313_141338.jpg
 
Looking at the back corner of the valve cover gasket, has that popped out? Big clean up job, but if it's as simple as the valve cover gasket then I'd be thankful!

To get so much oil on top of the thermostat housing it would have to be coming out from up high somewhere I'd have thought? Otherwise the likely culprit would be the pushrod tube seals.
 
Goldnrust said:
Looking at the back corner of the valve cover gasket, has that popped out? Big clean up job, but if it's as simple as the valve cover gasket then I'd be thankful!

To get so much oil on top of the thermostat housing it would have to be coming out from up high somewhere I'd have thought? Otherwise the likely culprit would be the pushrod tube seals.
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Good call. One shredded gasket. It was new, so very disappointing.

20240313_150000.jpg


On another disappointing note, the car is no faster with the new cam.
 
Well easy fix at least...

Disappointing that the cam has not helped, I guess that cam timing wasn't the liming factor in your top speed.

On another note, and possibly important one, it might be the picture, but it looks as if your rocker assembly might be installed incorrectly? The centre section should be pointing directly down, where it slides over the tube that feeds pressurised oil up to the head. See attached photo.

If that tube is not attached then the rocker arms are not lubricated and will be damaged. Also high pressure oil will squirt about wildly inside the valve cover, possibly resulting in low oil pressure.
 

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Goldnrust said:
Well easy fix at least...

Disappointing that the cam has not helped, I guess that cam timing wasn't the liming factor in your top speed.

On another note, and possibly important one, it might be the picture, but it looks as if your rocker assembly might be installed incorrectly? The centre section should be pointing directly down, where it slides over the tube that feeds pressurised oil up to the head. See attached photo.

If that tube is not attached then the rocker arms are not lubricated and will be damaged. Also high pressure oil will squirt about wildly inside the valve cover, possibly resulting in low oil pressure.
Click to expand...

The cork ones are rubbish. the originals were a rubber/fabric composite. In any case, it is very easy to dislodge the gasket whilst installing the rocker-cover. All this is not helped by the fact that tightening the cover requires a bit of judgement, as it is easy to overdo it and cut through the cork or rubber.
 
fiat500 said:
The cork ones are rubbish. the originals were a rubber/fabric composite. In any case, it is very easy to dislodge the gasket whilst installing the rocker-cover. All this is not helped by the fact that tightening the cover requires a bit of judgement, as it is easy to overdo it and cut through the cork or rubber.
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Motobambino now stock a silicon quality rocker cover gasket. Also by continually over tightening the rocker cover nuts you are in danger of collapsing the rocker cover to the point that it will foul the rockers.
 
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