Adjusting bucket & shim type valve clearance

Adjusting valve clearances is relatively easy when it's an engine with adjustable tappets, but it's a little more involved when buckets & shims come into the equation...
Here's a short video running through how to take current valve clearance measurements, comparing to specifications, removing the shims for the valves that require adjustment, calculation of new shim thickness, instillation and final clearance checks.
If you have any questions then please add them to the comments section below and I'll do my best to help.
Andy Mechanic

[@ash4pm]

Many thanks for posting this - it really helped my understanding of how the cam/bucket/shim/valve all operate together and, obviously, how to adjust clearance with difference thickness shims. Very well demonstrated too.

[@H2yprboy]

Used this video to check how to replace shims before changing the camshaft. Very useful!

[@TheWarjunkie666]

Earned a sub man. Helped me sort out my 94 gsxr 750. The teardown manual was worded very confusingly. Cheers from Canada Andy.

[@raymondsmith6315]

Excellent for those of us with DOHC Japanese engines. Different specs and details but the overall procedure is the same. Applying this to my 1UZFE v8. Has a very noticeable "tick" which is typical for my engine type. Mine has 380,000 miles on the clock and likely has never been adjusted. Edit: Some people just have that ability to speak using the appropriate language and tone to engage the student. Our friend here is a great example. A gearhead like me can listen for hours and would seem like minutes.

[@lowriddin99]

great video Andy helped me out figuring out my shims on my Polaris sportsman 570

[@AndyMechanic]

+Wesley Nelson Cheers Wesley, thanks for the feedback. Andy

[@MrRobert1603]

Yes your right remove material from the shim - keep it up & we'll keep learning

[@Brucelee-dw7tw]

Very good video, clearly.

[@garethmcnally5349]

top man...well docunentated

[@TorgeirFredriksen]

Hi Andy, just became aware of your channel (youtube recommendation!). Seen a few of your videos now, and must say that you have too few subscribers and views :) Very much like your thorough videos and editing, and just had to subscribe (twice!)

[@TorgeirFredriksen]

The only annoying thing is the frequent commercial breaks.

[@TheProPilot]

Hey Andy! Great video. If I am wanting to convert to shimless buckets how would I go about doing that with confidence? Cheers.

[@aaronlfcynwa2951]

Now I get it..if valve clearance for tappets, we use feeler gauge on the tappet, and if valve clearance for bucket&shim, we use feeler gauge on bucket and camshaft lobes

[@qapsukalek]

Is this the same head as 2016 kodiak and grizzly 700's ?

[@iantahmasbi]

Right!

[@tazgrant4521]

Pulling buckets out with plyers is not recommended due to marking surface. Magnetic tool or valve grinding sucker tool once oil removed on top of bucket is a far safer way to remove bucket. Damage to surface can damage cam lobes aswell as head. Plyers not recommended!

[@FranciscoGalicia]

Great video. I sanded the valves against the head valve. So it mean that I need thinner shims? Thanks you!! Kz650 1978

[@AndyMechanic]

Yes, most definitely.. make sure you get the clearance back to within spec. Cheers Andy

[@johnboy3100]

On a twin cyl sohc motor, after you have # 1 cyl on TDC do you have to change to check valve clearance on #2 cyl ? This is a Webber 850cc shim type valve clearance engine.

[@AndyMechanic]

Yes, you'll have to rotate the crank to TDC on the firing stroke of the 2nd cylinder - usually a full 360 degree turn of the crank shaft. Hope this helps. Cheers Andy

[@yemoteiyemstay8284]

Hi Andy! I would like to ask if you could explain my shim sizes states 188 and 182 and 175 and 186 but why are mine thrree digits and not as everyone elses with 2.675 or somewhat closer to 1.985 or four digits. Please explain 😊

[@petar443]

I have a question. On cars, especially on my 2008 Kia Optima 2.0 DOHC with mechanical bucket tappets - the valve clearance decreases or increases with time passing?

[@AndyMechanic]

+Petar Valve clearance usually reduces as the engine wears. Though sometimes on old push rod engines it can increase. Hope this is of help Cheers Andy

[@oscarfranciscosantanafranc8948]

Thank you Andy. This is a great video. Can you tell me please what dimensions have shim/valve toyota rav4 2.0l engine 3s-fe?

[@AndyMechanic]

Hi, I'm sure that engine has hydraulic tappets so no adjustment required Cheers Andy

[@oscarfranciscosantanafranc8948]

@@AndyMechanic ok thank you very much.

[@reocartwright9700]

Have the same problem with my wr 450 need shimming

[@MrRobert1603]

you could ---- with emery sand paper remove some material from the top of valve --- may take awhile ......another good job..

[@AndyMechanic]

+MrRobert1603 Now that's not a technique I have come across & well, you may as well reduce the old shim than have to remove the valve as that requires the head to be removed. Plus, removing material off the top of the valve may compromise the collet groove?

[@skynet000001]

You said go with the highest clearance number to make it last- i don't understand how that would make it last longer? Wouldn't more wear make it more clearance?

[@AndyMechanic]

As the valve seat wears the clearance reduces

[@emmanuelchay]

existe alguna forma de traducir tu audio al español???? tengo una Super Sherpa y me interesa poder entender tus tutoriales.

[@AndyMechanic]

+Emmanuel Chay yes, that's fine. No problem.

[@JoseSandoval-ic5xe]

Hi I wanted to ask what happens when these clearances aren't in spec??Do you lose compression.

[@AndyMechanic]

If the clearances get too small then yes, as the engine warms up the valve doesn't fully close. Cheers Andy

[@JoseSandoval-ic5xe]

@@AndyMechanic Awesome thank you very much for your response, I'm thinking this is what is happening to my Kia as I can also hear more ticking noise than before.

[@martinparker6536]

17:03 use a toffee hammer or plastic mallet or plastic drift/rod.... dont lever you could slip and damage the journal or mating surface for cam caps. 18:24 use a magnet.

[@Poobumwee]

Should you compensate for cam wear?

[@HalfdeadRider]

You are measuring the clearance for expansion! 🤷‍♂

[@AnthonyJordanWairoaboyNZ]

I hope I can wet sand my shims on mazda 626 DOHC

[@hankpb1]

the thickness of the bucket not come into the working out?

[@AndyMechanic]

No. You are measuring the current gap between the bucket & cam lobe. Then calculating what increase/decrease is required to obtain spec gap. Cheers Andy

[@stevep9221]

Why are the clearance's going to close up with wear? Surely as they wear the gap will get bigger. When the gap gets bigger the cam shaft will not be pushing down on the shim/tappet as much and the exhaust valve will not be opening enough. If the exhaust valves becomes out of spec (are not opening enough) less air is being sucked through engine and this when they over heat and pistons fail. I am a complete novice so someone put me in my place and tell me why I am wrong?

[@donovan4009]

Why does the clearance between the cam lobe and the bucket became decrease over time? Shouldn’t it increase as the bucket becomes thinner and thinner over time???

[@AndyMechanic]

On an overhead cam arrangement the valve margin - the sealing surface of the valve to the valve seat wears so the valve sinks into the head & moves upwards towards the cam. Reducing the clearance. Hope this helps Cheers Andy

[@donovan4009]

@@AndyMechanic thank you! That makes a lot of sense. One last question! Do you think that valve clearance increases or decreases with a hot engine compared to a cold engine. Because some say that valve clearance is bigger when the engine is hot and others say that it gets smaller with a hot engine. What’s your opinion on that???

[@AndyMechanic]

Again, it depends on the design. With an overhead cam arrangement the clearance reduces as the engine warms up & the components expand. This may be different with push rod valve train design - you will have to do more investigation! Cheers Andy

[@donovan4009]

@@AndyMechanic thanks !

[@bigwheelsturning]

Quick video? How about the next two hours getting the cam back in place? Setting up the chain tension-er? Would never buy another Yamaha in my life!

[@AndyMechanic]

+bigwheelsturning well fortunately that was a Kawasaki Sherpa! Cheers Andy

[@jfro5867]

Now I see why ZZR14 owners wince over this job.....

[@hankpb1]

tr7 is the same...stupud design