Author Topic: Tappet covers  (Read 1425 times)

oldchuffer

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Tappet covers
« on: April 12, 2022, 05:04:49 PM »
Progressing well with my "box of bits" rebuild, engine in frame and cylinder head on with camshaft, all good so far. But came to a halt today, on the cam cover 4 of the tappet covers came off fine but the remaining four just wont budge, tried heat and even an impact driver but nothing. As the heads are pretty much ruined i thought i'd try cutting a nick in the side and tapping it off with a hammer, but still nothing.

Before a get my angle grinder to them with the hope of "gently" cutting them off somehow, does anyone have any ideas? Are they renowned but seizing solid? Surely they are not torqued up to any great degree.

Offline Nurse Julie

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Re: Tappet covers
« Reply #1 on: April 12, 2022, 05:18:47 PM »
Yes, they can be a bu**er to remove at times and they should have only just been nipped up when fitting. Very old, flattened O rings can cause them to not want to undo without a fight.
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oldchuffer

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Re: Tappet covers
« Reply #2 on: April 12, 2022, 05:32:26 PM »
Thanks for the info, i'm thinking i may just get a  replacement cam cover (400fourbits has some) as i doubt i'll be able to get the remaining four caps off without causing damage.

Offline smoothoperator

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Re: Tappet covers
« Reply #3 on: April 12, 2022, 07:26:42 PM »
I had 1 awkward one off by hitting the edge with a hammer and chisel. The tappet cover broke and came off easily, with no damage to the rocker cover. Replacements are in good supply.
Steve
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Offline McCabe-Thiele (Ted)

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Re: Tappet covers
« Reply #4 on: April 12, 2022, 07:32:53 PM »
Thanks for the info, i'm thinking i may just get a  replacement cam cover (400fourbits has some) as i doubt i'll be able to get the remaining four caps off without causing damage.
I would persevere with removing them - personally I see the head and the cam cover as a matched pair through common wear patterns.
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Offline Oddjob

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Re: Tappet covers
« Reply #5 on: April 12, 2022, 09:16:47 PM »
You can always get one to come off, never had one beat me yet.
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Re: Tappet covers
« Reply #6 on: April 12, 2022, 09:36:21 PM »
Me neither

Offline Laverdaroo

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Re: Tappet covers
« Reply #7 on: April 12, 2022, 11:19:36 PM »
Swear at it more!
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Offline JezzaPeach

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Re: Tappet covers
« Reply #8 on: April 13, 2022, 07:42:20 AM »
If you haven’t tried a ring spanner yet I’d use that held down firmly (one shaped so the force is not lost) plus a club hammer. A sharp blow but not too hard.
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oldchuffer

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Re: Tappet covers
« Reply #9 on: April 13, 2022, 10:12:02 AM »
Thanks for the encoraging words, i will have another try, nothing to lose. I have tried a ring spanner and even an impact driver with the correct socket attached. I think the hammer & chisel method is next as the heads have rounded off.

Offline Laverda Dave

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Re: Tappet covers
« Reply #10 on: April 13, 2022, 10:20:04 AM »
If the cover is off the engine use a bench vice. Grip the flat of the offending tappet cover in the vice and turn the cam cover around it, worked for me👍
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Offline Oddjob

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Re: Tappet covers
« Reply #11 on: April 13, 2022, 02:58:16 PM »
I've used the old hammer and chisel method a few times and it works, ok it knackers the cover but it was knackered anyway so no real loss.
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Accidents in the back seat cause kids.

oldchuffer

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Re: Tappet covers
« Reply #12 on: April 13, 2022, 05:09:09 PM »
Some good news: I sat outside today in some lovely Anglesey sunshine and attacked the caps with hammer and chisel, two started to eventually rotate and unscrew the other two were more obstinate and just broke up, leaving the screw bit intact. I used a junior hacksaw blade to cut through in a couple of places and then it released. Pleased to say all threads intact too. Result!  Many thanks for all the advice.

Offline Laverdaroo

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Re: Tappet covers
« Reply #13 on: April 13, 2022, 06:05:20 PM »
Nice one, well done mate! ;)
Mornings are the invention of the devil!

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2002 VFR800 VTEC (The Beloved)
1977 CB400F (the last money pit!)
1998 Ducati 748\853 conversion(sold :()
1980 ish CB750KZ in a billion bits (need to get rid, anybody want one?))

Offline Yetanotherbike

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Re: Tappet covers
« Reply #14 on: April 13, 2022, 06:54:10 PM »
Well done that man! I was going to suggest gland pliers have worked for me in the past, but no need now. :D

 

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