Tappet Covers

[andut]

Anyone else had tappet covers seize and if so is there a trick to get them free ?  Most of them behaved, but I've managed to round off 2 that don't want to play - bloody ally caps are as soft as cheese !

Tried to get some purchase with a screw driver on the wide edge of the cover, but I'm now breaking the cap into pieces.  Is this familiar to anyone ?  I'm starting an engine rebuild (first) so how important is it to loosen tappets before lifting the rocker cover ? 

Thanks for any help / guidance !

Andy

[Trigger]

These are sometimes a pig. You have to put a ton of heat to get them moving sometimes, i have even had to drill them out. Take the rocker cover off and you will stand a better chance.

[andut]

Thanks Trigger - glad it's not just me ! 

[Bitsa (Ralph Wright - RIP)]

A while back yours truely restored a 400/4 stripped it all down blasted in some form or another to finally reasemmble to find out after relpacing the tappet covers could not get the frackin things back off without destroying the threads on the cam cover.Discovered that and did not make the same mistake with my 750s is NEVER ASSEMBLE ali to ali without grease if you do down to you.
Cheers
Bitsa

[Johnwebley]

 I recently bought a couple of caps for my 500 from DSS,I got the pattern ones,turns out they are slightly deeper,
when I removed one to check the tappet,I noticed a mark were the rocker had been hitting it,

BTW,they are damn expensive !!!

[Trigger]

I recently bought a couple of caps for my 500 from DSS,I got the pattern ones,turns out they are slightly deeper,
when I removed one to check the tappet,I noticed a mark were the rocker had been hitting it,

BTW,they are damn expensive !!!

I know the ones John, Bloody things. Where did the alloy that the arm knocked off the tappet cover go ? That was my question to one of DSS bods.

[mike the bike]

I use a 17mm impact socket to remove them, a hexagonal socket not a bi hex.

[Johnwebley]

I recently bought a couple of caps for my 500 from DSS,I got the pattern ones,turns out they are slightly deeper,
when I removed one to check the tappet,I noticed a mark were the rocker had been hitting it,

BTW,they are damn expensive !!!

I know the ones John, Bloody things. Where did the alloy that the arm knocked off the tappet cover go ? That was my question to one of DSS bods.

 I am fairly sure nothing broke off,just a crease were the rocker hit it

[Nurse Julie]

I must have been very, very lucky when I took mine off, had absolutly no problems at all. Good thing to by the sounds of it 

[Drew400]

Hi Andy, I struggled slightly, but clearly not as much as you.

I replaced a few c/o DSS after burring their nut edges. If they're any use to you, PM me and I'll send them over.

Cheers,

D.

[steven400/4]

had the same problem as you lot i was rounding them off trying to get them out spoke to a friend of my in his 70,s and was an honda tec for 45 years the problem is we all think thay are 17mm witch is fine when they are loose they are more like 16.5mm i got a 16mm spanner and file,d away some to get a nice fit on the caps . never had a problem since with taking them out

[hairygit]

The biggest cause of problems with tappet caps is being tight with money! Personally I wouldn't use the rubbers on them more than twice, as people tend to overtighten them due to not wanting to pay out for replacement "O" rings, thinking that if they're tight, they wont leak. False economy, as the rubber of new "O" rings does 2 things, stops oil leaking out, and when new they act like a spring washer, meaning they do not need to be very tight to avoid leaks, but also stops them vibrating off. So the ball's in your court boys and girls, skimp by using old "O" rings, and have loads of aggro and expense for new caps as well

[Clem2112]

I am sure you could find viton o rings of that size somewhere - worth checking !