Car Analogy

Right, if you stop the trans input shaft from spinning, by putting into second or any other means, and THEN you put into first, no thud. Exactly like B stated (except he mentioned first put into first, but any gear will do it, second or anything else).

The OP only had the car 6 weeks. Plus like most of us, after a repair we're hyper aware of any little thing, until we relax and enough time goes by we stop worrying. He even admitted he wasn't 100% sure the thud wasn't there before.

Its just something he didn't notice before.

BTW, OP you didn't have to replace the clutch master or follower cylinders. You just had to do a full fluid swap, probably more than once. But no biggie.

Just keep fluid clean to prevent happening again. Like every other oil change, turkey baster the reservoir, wipe clean, fill with fresh fluid. Obviously don't touch pedal while reservoir empty. This will be enough to keep fluid perpetually clean, and avoid future leaks.

Dirty clutch fluid leaves deposits on shaft. These cause uneven surface, which causes small leak with each clutch press. Fresh fluid after full fluid swap will have a detergent effect on these deposits. After a few weeks leak goes away. But fluid gets dirty again from this cleaning effect, so might need a second fluid swap soon after first. From then on just need regular reservoir fluid swap to keep it clean.

Its rare our clutch hydraulics actually go bad. Leaks almost always just dirty fluid.

I'm willing to bet shop adjusted clutch too loose. Watch this youtube, and redo tbe adjustment (tools needed: open end 12mm wrench, flashlight, small, flexible body to get yourself under dashboard). I'm old, not small, never was flexible, and I can do it. There is some swearing and old man grunting involved however.

Jub

^Can confirm that adjusting my free-play made the car clunk less, if at all. I think bleeding and adjustment will "fix" it for the most part.

dtsol

I will bleed and adjust. My clutch, that is. Thanks for all the great info!

Mr.Matchbox

Members here allways complain. But as you are the Professional, i am willing to change my Opinion.

EDIT: i have switched all my Motorcycle clutches to DOT 5 Silicone brake fluid to get rid of the hassle of bleeding and so on. I think i will do this at the S2000 to. This year.. or next year...

B serious

Using a 1 man bleeder is best. It should take only a few mins to fully bleed out the clutch.

Car Analogy

This...unless you partially emptied the system. Changed hose, changed master or follower, let reservoir run dry while bleeding, etc. Then sometimes it air locks and doesn't want to get started. Kinda like finger on straw effect. Surface tension of fluid keeps it from flowing.

In that case you migjt be able to get it going by pressing pedal slowly with bleeder open. If that doesn't work, next step is two man bleed, pump pedal bleeder closed, pedal down, crack bleeder open, bleeder closed lift pedal. Resume.

If none of that works, a pressure bleeder might be required.

You can avoid all that by just keeping fluid fresh. Every other oil change or at least once a year or two, turkey baster reservoir, wipe clean, refill fresh fluid. Preserves both hydraulic cylinders, doesn't introduce air so no need to bleed.

windhund116

I like using a syringe to draw up hydraulic fluid. Helps keep it from dripping on the paint.

Car Analogy

Very nice! I have something similar.

Definitely don't literally use a turkey baster. Meant 'turkey baster' as a verb, not a noun.

dtsol

I bled the clutch yesterday. It definitely needed it. The ka-chunk is really minor now (not sure how to represent it in words anymore), and the pedal feels much better.