Britbike forum Forums British Motorcycle specific Brands Triumph bulletin board refitting tappet guide block, t140?

looking for guidance
removing the tappet guide blocks from the cylinder block was straight forward enough
is there a secret to their refit including ensuring the o rings remain seated correctly?
i know they must align with the set bolts and that intake side differs from the exhaust side.
thnks cliff

I always use a smear of black silastic towards the top of the block [as well as the o ring], keep the tool as straight up and down as you can, if you need to,use a spanner to rotate the block as you hit the tool - you will only get very small rotational movement doing this, its more about finessing, getting the alignment exact. Support the underside of the barrel and the outer block housing where the locator bolt screws in, don't want to snap or crack the barrels at the thinnest part of the housing hole. Smaller hits are better than big thumps.

My experience at fitting tappet blocks pertains to a T120R, but the process must be similar for a T140. If they offer any help, here are the notes I took the last time I did it -

On his DVD, Hancox says to line up the hole in the blocks with the locator screw hole in the cylinder block, but doing it this way does not guarantee that the holes for the tappets will be parallel to the camshaft. It might be a better idea to make the holes square to the camshaft - the screw holes will be lined up if the block is square to the camshaft.

Due to the closeness of the tappet holes it is difficult to get them lined up perfectly - next time use a straight edge on the edge of the holes to make it easier getting them properly lined up.

Hi Cliff, I have experience on T140.

You must have a proper tool like factory one with the 2 pins that fit into tappet block hole. That is a given or you are at risk of breaking block.

Factory didn't seem to worry about tearing o-ring or leaks so they left roughness on most surfaces. We want to do better.

Take a visual look at tappet block where it fits into block & oring groove. Take some fine emery cloth & smooth sides & edge of ring groove. Don't reduce diameter of block or round corners of groove, but smooth them some & they will now feel smooth instead of rough from the tooling.

Do same for bore in cly. Pay very close attention to the small chamfer at top of bore where tappet block enters. This is the prime area that damages oring. Smooth that very well so ring will compress easily as it slides by.


Verify you only use viton orings as they resist leakage much longer.


I personally lubricate the bore, block side & o-ring. I suppose rubber lube is best, but I use wheel bearing grease or even motor oil. Have never had ring tear on install or leak. I don't like dry install. I used to glue top edge but found not needed. Glue top if you want, no harm done, but make sure sealant does not get near tappet oil passages. Late T140 eliminated oiling to tappets so there it doesn't matter.

I set cyl on a redwood rough saw 4x6 board 14" long. I find a place on concrete floor where board sits nice & flat. Set cyl. on this.

Remember tappet blocks don't go straight but slope slightly so keep the angle correct best you can when knocking in. I don't cool or heat anything. Just room temp all parts.

I'm with Hermit 100% about aligning block to cyl best you can. Bolt hole you can be way off & bolt still go in fine. I've seen installed crooked & wear pattern on block ears corresponded unevenly. But is outside of spigots perfect?? I feel better aligning it this way though.

I line up bolt hole by eye & start driving in. I use hammer the size shown in drawing in shop manual. I find that works good. Just at least close in size.

When about 3/4 I measure using squareness using straight edge & depth gauge. I put straight edge in tappet block & hold firm to ears. Then use depth gauge to measure to each spigot for cyl bores. Record measurement. I mark block with felt pin so I rotate correct direction.


This sounds crazy but works. Grip the driver tool tightly. Push down hard & turn tool in direction block needs to rotate. Turn hard but only by hand. The continue driving block. It actually will rotate rather nicely as you drive it. Never ever force it to turn. The block will turn only as it is moving! It only turns a tiny bit at each hammer blow.


Go a little deeper & measure again. Check your progress as you go. Sneak up on squareness. When the o-ring gets close, observe it carefully looking for any rubber peeling off. Even a trace of rubber is a failure. Remove block, verify surfaces smooth & get new ring, more lube. Start again.


Often you may miss square when block is seated. You'll hear the block seat as sound of hammer blows will obviously change. There is chamfer on bottom of block so you often can't really see if down home visually. But you can feel & hear it.


So if not square record measurement & for sure use felt pin to mark desired direction both top & bottom of block. Flip cyl over. Again pushing hard down & turning drive block out slightly. Measure again drive a little more if needed but be mindful where o-ring is don't let o-ring rise out of cly. Look at parts before hand so you know where ring is. Memorize that. Now again recording measurement drive block back home. Repeat this zigzag up/down until block is square. 1st one is hard. The next is much easier as you get feel for how much to turn it. Don't give up. With a little practice not difficult. I try for less than .002" difference left to right.


If this is confusing on how to measure PM me your email & I'll send photos of the straight edge & depth gauge. A normal 6" Verner caliper can be used for depth gauge.

Don

Another thought. I agree that you must use the right tool. I've bought used tappet blocks that were driven in and out with a punch which will easily distort the hole for the tappet. I also filed the corners off the bottom of the tool as I had two blocks lose an ear while I was installing them. Could have been the blocks had weakened ears from a previous operation but I decided it wouldn't hurt to take a little off the sharp corners. I wonder if anyone else has experienced such happiness......The broken ears was why I went shopping for more tappet blocks.

Cheers, Wilf

Yeah, watch some tools, they are slightly oversize and can break the guides/ears when removing the guide block, and then the pins can be oversize and jam in and distort the cam follower holes. If yours is like this, file or machine it down so it is the correct size.
And as my mate Stephen pointed out, when I said hold the tool straight, I meant straight to the block, not the barrels....some guide blocks go in at a slight angle.

all advice much appreciated
have the correct tool and will ensure nice fit before banging
what is the eventual vertical level?
is it top of tappet blocks to align with top of the corresponding holes in the cylinder block?
is the tappet block with the oil way associated with the exhaust side of the cylinder block?
thnks cliff

The correct height is determined by the sound of it being banged in. Clank clank clink and it has been driven all the way home.
Second question....not sure what you mean.
Third question, yes.

Cheers,
Bill

Hi Cliff, Like HawaiianTiger said, you simply drive the block home to the shoulder.

The exhaust tappet block has the oil groove & an o-ring groove. When block is driven home to shoulder the oil ways automatically line up. So exhaust block has 2 grooves & you can plainly see the oil drillings in groove & in the bores for tappets if you look close.

I'm sure you know this but the oilways & blocks need to be perfectly cleaned before you install. Then add orings & assembly lube. Again verify oil ways clear. After installing blocks yet again verify clear. Finally pump oil into oil feed hole right front underside of block & verify oil comes out of both feed holes for tappets.

Just incase you have wrong tappets measure the width of the flat on tappet stem. The correct tappet for T140 has a 3/32 wide or should I say tall flat. The early tappet has a 9/32 wide flat. If you put 9/32 flat tappet in my mistake you'll have low oil pressure.

The intake tappet block & tappets have no provision for oil feed. You didn't say what year your cyl is but again the latter T140 eliminated oil feed in both cyl block, exhaust tappets etc.


So after this inspection all you need to worry about is the squaring of the cyl block.

Don

Ok just remember it’s not dead vertical.

1981 was the year oil feed to the exhaust tappets was deleted, and the tappet blocks and small radius tappets were then the same, ( previously, "R" tappets were used for EX, and small radius for IN )

good tips
will check oil ways as instructed and align tool when banging
judging by instruction tappet block can only be driven so far down and not further??
thnks cliff

I agree with everyone.. The tool is the most important thing! Maybe I'm the only one doing it but.. I prep the block clean, with new o-ring etc. and drop in Refige overnight,,not freezer..

Next day prep the hole nice and clean and make sure no burrs or anything.. Yes you can't go past but just don't gorilla hit them in..

So I chock the block in something securely that won't break anything,,warm the cyl block pretty good. - Use you favorite way, torch, warming plate etc.

Get the tap block from refrige, line up as good as you can and it should go in with the tool very easy.. No heavy hitting with a big,heavy hand sledge etc!!

IF your off a bit. The real tool has a hole in the handle.. You simply, quickly, put tool back in , put a rod or long bolt thru it and you should be able to turn the block to align the block with hole..Maybe by hand or with slight tapping on rod with something ..... Read everything in all these posts and you won't have a problem...

If it hasn’t already been said, the tappet block isn’t quite parallel with the bores, so it’s not dead perpendicular to the flange. The exhaust block leans back; the inlet one leans forward.

Hi Cliff, Gaspar & I see things differently which is fine. I want no offense to him as it clearly works for him. He has a skill set you or I don't have

My very strong suggestion. DON'T EVEN THINK ABOUT TURNING THE BLOCK UNLESS IT'S MOVING in or out. Pretty much every block I've seen with broken ears was wrong tool or turning it without it moving.

Unless you have great skill you will certainly break the block if you turn it as he does. I used to heat cyl & chill block. I found the tappet block got heavy condensation on it. In my view that could lead to rust down the road & maybe make block harder to get out later. Just my theory so take it for that. After the firts few I just started doing them at room temperature. By time I got block lined up the way I wanted it the temp of cyl & block were the same anyway. I think you removed it, wasn't very hard was it?

Again you just drive it in until shoulder on block stops against cyl. You can hear & feel it when shoulder hits. The hammer sounds different as it strikes tool. Very solid feel & sound. Look really close with flash light & you might... be able to see the shoulder all the way down. Often the casting of cyl & chamfer on shoulder of block blocks your view of the part of shoulder that contacts cly.

I think you'll find this is a relatively straight forward job. You'll see how you can turn it while you're hammering. As was stated you don't need to hit extra hard with hammer, just like driving a nail is all. The first one I did I was terrified the cyl was going to break or the tappet ears would break, or it would get stuck somehow. I understand how it feels to simply not know how to do this. Trust me you'll be fine.
Don

Hi Cliff, If you want to see photos of how I measure for squareness PM me your email. I can't post photos here.
Don

Regarding the issue of condensation in such applications, I have found a quick dip in clean solvent, or wipe with same, disperses the moisture while still maintaining sufficient coolness for fitment !

yeah I've been doing it for close to 40 years.. I have seen some tools without the hole midway down!! I get it down to one fluid movement. Tap block out grab with paper towel it'll be dry and just place it in the secured cylinder block quickly, tool in,couple taps and its in..

Good tip from Don.. do it calm and nice and quiet,,you will hear when the block is in/seats ..

thnks Don and all contributors.
much more confident now
i'm just waiitng on warmer weather to paint the cylinder block before fitting the guides
will definitely pm you for those photos when ready

cliff

Interesting, Gaspare, I've only been involved with motorcycles for 48 years, Triumphs specifically for 42, and the learning process is never ending ! With the more knowledge acquired also comes the realisation of how much more there is to know!

I wish there was a 'like' button.
And you can turn the block from the top as you tap it in. As stated the tool has a hole - or in my case - a flat that I can fit a spanner on. I continue tapping and applying pressure on the spanner at the same time as I tap. You are only trying to turn the block a very small amount this way. Its just getting it exact. If you are trying to turn it more than a millimetre/1/16" or so then its better to remove it and restart.

And never turn the block with force, or if it is completely seated, you will break it. I've seen both the guides/ears and the tops of the holes broken by ham fisted Neanderthals.