12aJBridgeport

Before installing front cover I measured end play at .0020" using the lift the flywheel by hand method. With a used crush washer on the e-shaft bolt and no assembly lube on the front stack. Then I installed the front cover (with new gasket and silicone, new o-ring), put a new crush washer on the e-shaft bolt with some silicone in front and behind the crush washer, and assembly lube on the needle bearings + thrust plate and now I measure .0014" end play when lifting the flywheel.



If I put a long screwdriver under the front pulley, and lift it rather hard, I can get exactly .0020" and absolutely no more. So should this motor be installed or should I redo the end float. ?????



The mazdatrix video says to set the end play dry then move on. Am I okay like this?

fc3sboy1

if your dry was .002 your fine. .0014 wet is fine aswell.

12aJBridgeport

I ended up removing the pulley and reinstalling. With much less silicone under the bolt and only torqued it to 80 ft lbs. Got .0019" wet when lifting the flywheel and .0025" wet when prying on the front pulley.



It was interesting to see the affect of e-shaft bolt torque vs. endplay. Also minimal effort to increase torque from 60 to 70, and 70 to 80. But to go from 80 to 90 ft lbs the bolt had to be turned 1/8 of a rotation.

j9fd3s

if you're running the lower tq number, mazda has a little thing that goes over the crank bolt and secures it to the hub so it can't come loose



mazda number N350-11-408A



it seems to be stock on some of the S5's and the later FD's

12aJBridgeport

Does it bolt to the front of the pulley or something? Does the crank bolt need to be removed? It does sound like a great idea.



I did use blue loctite on the threads and 80 is in the middle of the 72-87 tq range for the S5 motor. Heck my REPU shop manual says to use 60 ft lbs!

j9fd3s

yeah it goes over the 19mm bolt head and gets held on by 2 of the main pulley 6mm bolts

fc3sboy1

all s5 nas that i have worked on and most of the s5 t2s had them aswell as all stock fds had them. its a stamped steel cover that goes around the crank bolt and you use 2 of the m6x1.00 bolts for the pullys to hold it into position. unless the keyway breaks there is no way for the crank bolt to walk out.



secondly when your setting end play your supost to do a full dry run to spec with the proper tq on the crank bolt so thatway when you go to do your finaly assembly it will not move. i never use assembly lube on the bearings only vr1 50wt oil and never had any issues so far.

Lynn E. Hanover

The object of the end play measurement is to assure that there is room to allow for a bit of crank flex, that tips the hard washers out of flat against the bearings when you scream the engine. So .002" is the minimum for street use.



The bearings are not very strong and tend to fail if abused.



The thrust plate is very flexible, so when you pry with a lever to move the crank, that extra clearance that seems to appear is actually the plate flexing. Have the engine horizontal when measuring end play. Use only your hands to move the crank to measure end play.



Super killer monster high spring pressure clutch covers can cause an early death for the rear thrust bearing. When you push that pedal down the throwout bearing pushes the clutch diaphragm spring against the rear thrust bearing, in order to release the clutch. Sitting at a light holding the clutch pedal down is asking for trouble.



If you buy an engine that has been stored sitting on its flywheel, discard the thrust assembly before using that engine. The thrust plate will be coned and the bearings will be junk.



It is typical to torque the nose to 95 to 100 pounds and have .0025" of end play. This is to help stiffen the nose against side loads of the belts and in the case of an external oil pump. Not required for the street.



Longer spacer sleeve = more clearance. Shorter spacer sleeve = less clearance.







Lynn E. Hanover