Mod Details
PremiumNo Difficulty
Mod ID1888
Creditevilution
For
Linkhttps://evilution.co.uk/mod/451-valve-clearance-checking.htm Copy to ClipboardSmart state that the inlet and exhaust valve clearance should be checked every 56,000 miles. I have never known anyone actually do this, including myself.
That’s why there are no photos. If you do check the clearances, please take some photos and send them over.
Access
Remove the cylinder head cover to reveal the camshafts and valve tappets (also called buckets or cups. I have always called them buckets but that’s probably a British thing).
Put the engine to top dead centre and check to make sure that cylinder 1 valves are not under load. If either valves are under load, rotate the engine crankshaft by 360°.
Checking Clearance
Check the valve clearance of:
Intake valve cylinder 1
Intake valve cylinder 2
Exhaust valve cylinder 1
Exhaust valve cylinder 3
Turn the crank pulley 180°
Check the valve clearance of:
Exhaust valve cylinder 2
Intake valve cylinder 3
This should be done using a feeler gauge. A feeler gauge is a tool comprising of a many blades of varying thicknesses. They fold out separately and you just fold out the combination of the thickness you require and stack these on top of each other.
Adjusting Clearance
Make a list of clearances for all 6 valves.
Remove the appropriate camshaft and lift out the worn tappet/bucket/cup. Look on the inside of the tappet and it’ll be marked with the thickness.
You will have to order replacement tappets that are thick enough to bring the clearance back into specification. Alternatively, you can fit bucket shims if you can’t get new buckets from smart.
Repeat this process with all of the out of spec tappets before refitting the camshaft and rechecking the clearances.
Important
Do not use a magnet to remove the tappets as this can magnetise them which will cause them to collect swarf and that will increase future wear.
Clearance Figures At 20°C
Intake valves = 0.18mm to 0.26mm
Exhaust valves = 0.26mm to 0.34mm
Bucket Information
The buckets for the intake and exhaust are the same part. These should be available from smart.
| Base Thickness | Part Number |
| 2.62 MM | A 1320540001 |
| 2.64 MM | A 1320540101 |
| 2.66 MM | A 1320540201 |
| 2.68 MM | A 1320540301 (discontinued) |
| 2.70 MM | A 1320540401 |
| 2.72 MM | A 1320540501 |
| 2.74 MM | A 1320540601 |
| 2.76 MM | A 1320540701 |
| 2.78 MM | A 1320540801 |
| 2.80 MM | A 1320540901 |
| 2.82 MM | A 1320541001 |
| 2.84 MM | A 1320541101 |
| 2.86 MM | A 1320541201 |
| 2.88 MM | A 1320541301 |
| 2.90 MM | A 1320541401 |
| 2.92 MM | A 1320541501 |
| 2.94 MM | A 1320541601 |
| 2.96 MM | A 1320541701 |
| 2.98 MM | A 1320541801 |
| 3.00 MM | A 1320541901 |
| 3.02 MM | A 1320542001 |
| 3.04 MM | A 1320542101 |
| 3.06 MM | A 1320542201 |
| 3.08 MM | A 1320542301 |
| 3.10 MM | A 1320542401 |
| 3.12 MM | A 1320542501 |
| 3.14 MM | A 1320542601 |
| 3.16 MM | A 1320542701 |
| 3.18 MM | A 1320542801 |
| 3.20 MM | A 1320542901 |
| 3.22 MM | A 1320543001 (discontinued) |
| 3.24 MM | A 1320543101 (discontinued) |
| 3.26 MM | A 1320543201 |
| 3.28 MM | A 1320543301 |
| 3.30 MM | A 1320543401 (discontinued) |
| 3.32 MM | A 1320543501 (discontinued) |
| 3.34 MM | A 1320543601 |
| 3.36 MM | A 1320543701 |
| 3.38 MM | A 1320543801 |
When I checked in October 2025, they were £11.40 + VAT each. For that price, you are probably better off using shims.
Markings
Thanks to Michael W (who seems to be the 1st person to ever do this), we have a photo.
The 00 means 3.00mm. So your buckets will show between 62 and 38.