THRUST WASHER SETS
Description
A set of four high quality thrust washers for the A-Series engine, as used in all builds here at MED. We have options to suit all but the very early inline/850 engines.
Available sizes;
- 1275 standard
- 1275 +0.003"
- 1275 +0.030"
- 998 standard
- 998 +0.003"
Frequently Asked Questions
Which thrust washers do I need for my A-Series engine?
We stock 1275 thrust washer sets to suit crankshafts with 2.000" main journals, and 998 types to suit the smaller 1.750" main journals. In addition, we keep oversize thrust washer sets to account for wear and subsequent re-machining of the thrust faces on the crankshaft. Early 1950s inline thrust washers for the 948 engine and 850 Mini are a bit different in design, and we do not keep these unfortunately.
So, which size do I need?
Aside from the 1275/998 difference, you will need to dry build your engine and check the crankshaft end float. This will determine which thickness of thrust washer you will require. Standard recommended end float is 0.003-0.005", but on full race applications, this may need to be increased to 0.008-0.010".
What can be done if the crankshaft end float is not right with the new thrusts?
If there is not enough end float on your A-Series crankshaft, it may be necessary to have the thrust washers surface ground down to the correct thickness by a competent machine shop. If you have too much, we keep oversize thrust washer sets that can either be fitted straight in, or machined down to size.
How thick should standard thrust washers be?
We typically find that standard 998 thrusts are nominally 0.090" thick, whereas 1275 types are closer 0.092".
Why does my A-Series engine wear the thrust washers out prematurely?
We find that the ACL thrust washers are the most durable on the market. If your engine is prematurely wearing high quality thrusts, check that the crankshaft end float is correct, that the clutch throw-out stop nuts are not wound too far out, and avoid sitting with the clutch pedal depressed for long periods of time with the engine running. This is especially important when using an extra strong clutch cover.