Replacing a VB tappet guide

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Mike Nash
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Replacing a VB tappet guide

Postby Mike Nash » Mon Jun 24, 2019 8:05 pm

Dear all,
As you can see below I need to replace a VB tappet guide and I seek advice on how its done. It seems to be exactly 2 inches long and if I drive it down into the valve chest to remove it there seems to be exactly the same clear length above it in the valve chest before it hits the valve guide. It all seems to be a bit tight; has anyone done it? Also, any tips on persuading the tappet guide to actually move?
Yours in anticipation, MikeN.
IMG_4551 (1).JPG

john.whiting
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Re: Replacing a VB tappet guide

Postby john.whiting » Tue Jun 25, 2019 2:43 am

Its already broken,so grind or file it level with the flange,and make /find a piloted drift and press it out.......no hammering.......you might break the flange......The other possibility ,if you dont have a press,is using a 3/8 HT threaded rod,and some spacers pull it into the chamber.My suggestion is find a press,or take it to an engine reco shop ,and have them do it.

nevhunter
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Re: Replacing a VB tappet guide

Postby nevhunter » Tue Jun 25, 2019 4:44 am

It might have a slight shoulder on it and need to extract upwards. This can be done with a suitable bolt and nut washer and sleeve and you might even be able to put the new one in the same way. (in the reverse direction) Nev

Mike Nash
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Re: Replacing a VB tappet guide

Postby Mike Nash » Thu Jun 27, 2019 7:55 am

VB tappet removal 27june219.jpg


Thank you for your advice, gentlemen!
I feared that after some 63 years in place it would be more difficult to remove than it actually was but with a sleeve and cheap threaded rod it came out quite easily and smoothly. The most difficult part was finding a suitable sleeve, but seeing a length of water pipe I'd used as a tree stake in the garden I saw that water pipe screwed unions would do the trick. So above you can see a "3/4 inch Black Malleable Iron Socket" in action; it cost £1.03 at a local plumbers' store who still stocked such stuff. (Woodstock Plumbing, South Way, Walworth Ind. Est. Andover SP 10 5BN - I should have bought two to get the proper length.)
The threaded rod is cheap 8mm metric DIY stuff and the nut on the end in the valve chest needed its corners ground down to pass through the hole in the barrel.
Again, thanks from MikeN.

john.whiting
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Re: Replacing a VB tappet guide

Postby john.whiting » Thu Jun 27, 2019 1:23 pm

Valve guides should be done the same.....always cut the guide off flush on one side,and pull from t'uther ,so carbon and rust dont score the bore in the barrel...An experienced mechanic can do it with one blow of a 4lb hammer,but beginners are advised to use a puller,like yours.


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