Welcome to part six of this low budget classic motorcycle restoration series.
The project's really starting to take shape now.
Today we'll make sure the valves are seating correctly, and we'll put the head back on the
cylinder to move the Everyday Bike Project along. Let's get started.
All these valve seat angles are 45 degrees. Now
the cutter I've got here is just to show you. I had to borrow one with tungsten cutters because
the valve seats are very hard material. This does polish it off a little bit.
So the idea is that it's supported again. So it's like a valve stem. Goes into the guide,
and the cutter. It's got a T-bar on here. I've got to keep the gloves on the head's still hot.
You just use these motions like this.
You can hear it.
Now if you look, it will start taking out the seat
Now when those old valves are in there, they're wobbling about.
And you can get literally, like a lip, and they start to pocket the valve if you're not
careful. But that now, I've cleaned that seat up. Just going to do a little bit more on this one.
These aren't bad actually. But I'm really just doing it to show you.
So those two inlets are done. Just turn it round. We'll do the exhaust ones. We re-cut the valve
seats for two reasons really. You find that the seat itself could be like an exhaust, they'll be
pitted. As these were a little bit. Also because the old guides are quite worn in the valves,
and the valves are going up and down, and coming down, and wobbling about, you lose the true angle.
So we've got new guides now. We've got new valves that are cut, machined up to 45 degree angle. So
we just now just clean this all up. When we put our valve in and lap our valve in
we get a really good seat. And that's what we're doing. We're just trying to true up everything now
and recondition it. These seats aren't too bad. I mean it's quite an old engine,
but considering the age of it, it's not bad. Just a little bit more on these exhaust
ones. The camera now can see the seat itself now is quite clean. You have a nice taper.
So that now is really ready for a valve to be just lapped in, then we put springs back in.
That job will be done. We're just going to do this one. A little bit more on this one to do.
We haven't washed any of this out from when we stripped the engine down, so we just want to
make sure it's all nice and clean. If you just check the springs, make sure they're
not cracked. Keep the springs separate. Probably they are the same but these are the inlet springs
and those are the exhaust ones. Sometimes with engines you'll find that the rating of springs
can be harder on the different applications, and we always just check the heights of the springs
as well. Just make sure they all look the same. What we're going to do now, we've cut the seats,
we're ready to put the new valves in. But we just need to lap these in with a bit of grinding
paste. We probably only need to use fine because the seats are cut, they're all nice and smooth,
they're not pitted now obviously. We've got new valves. Put a little bit of lube
on the valve stem. Inlet valve in. Now good idea have a valve sucker, just make sure
there's no oil, it's nice and dry, because you need a suction on here.
Get it central if it fits.
Okay. Now just a little bit underneath.
Don't need a lot because it'll take it round. But once you've got your paste onto your face.
Valve sucker. Use the palms of your hands and just rotate your stick.
Keep that straight and the sucker won't come off.
And occasionally just lift it and turn it a little bit so you're not just
spinning on the same bit all the time. You can hear it cutting. You hear the paste.
Do it a few times then we take it out and just check it. See what's happening. So we take
it out now. It's not bad. So the seats have taken a bit of punishment over the
years. We'll give that a bit more. It's got a little bit of a lip there but it will come out.
I'm just going to pull it out. So we've done one inlet valve, we're going to do
the other one. But we'll put the springs for the valve that we've done. So we've got the
primary, and we've got the secondary spring. That can go with that. And we've got the cup,
top cup, and the bottom cup. So really for ease, we stick that over the top of there.
That one's ready to be installed. We'll do the same on this one, we'll give it
three. Three cuts with the paste.
You can see the actual face now is nice and grey. There's the other valve. That's going to be done
on the other cylinder, on the other side. And that's a different colour. So we have a nice
seat finish there. We're just going to wash out
in the kerosene washer. Just all round the valve seats themselves. Just make sure there's no
residue or paste in there. So the build up with the spring components that are inside the guide,
you have your bottom spring holder cup, your inner inauder spring,
your top cup.
And then when the collets are back in
we have those retained
like this. So that would be inside. But the spring is under a lot of compression obviously
when the collets are in because the bottom cup is held into the top of the head.
A little bit of oil on the stem. Okay we're just going to use a valve tool now. Valve compressor,
just to pull up on the valve spring. Just make sure that this is in the centre of the valve.
Go a bit more with that, and we're ready to put our collets back in. Okay, we're trying to do this
with a magnet so you can see what I'm doing. We need to put one each side of the valve. One's in.
Because our valve compressor is not doing it very easily at the moment, I just need to open these
jaws out a little bit because they've been moved in for doing a different engine. It's not holding
the cup properly. The cutaway in this stem is a slightly different profile to the old valve.
If we put the collets into the stem it all looks quite straightforward.
But in practice we're trying to get that. Now we've had a bit of trouble with the other three.
My valve tool itself hasn't got a lot of surface area and we're sliding about. We get one collet
in and the other one gets jammed, or it slips out. So I've gone back to the other tool.
But there's very little margin when we compress this spring to open up the gap
to get the collet in, or to get both in. You get one in it's just a bit fiddly.
It's just one of those things. We'll try and put it over the back first and get this back one in.
So we release it with the magnet. Let me just get the screwdriver.
Just keep our finger on the top. We need a little bit more compression on the tool.
All right, that one's in. You can see it's quite tight for space. That's in. Now we've
got the valves back in. I normally just tap them with a hammer. Give them a tap on the top.
Just make sure everything's seated properly.
Right now the heads back together, we're just going to put it on the surface plate here to
make sure it's nice and flat. What I tend to do is just coat the block with a little bit of W-40 or
the equivalent. It stops the paper sliding about. We put our paper on there and then spray this.
This is 240 grit. Give it a good spray.
Get our head.
Put it on there. Put your hand on the centre of it.
And just backwards and forwards. Rotate it as well.
Just hang onto the paper a little bit. It shouldn't move too much because we wet underneath.
It should grab it a little bit. Just like moving an iron around really. Just keep that flat.
Just let the head slide on the paper.
The reason we're doing this is if the head's slightly distorted,
it will show up in a moment when we check it. We've put a straight edge underneath it.
We haven't got a surface block. A piece of plate glass would be alright.
A lot of people use grinding paste but I find that paste is... you're leaving it on the surface
and you're pushing the head across the paste and the paste is being pushed away. Well this is on
paper which is a wet and dry paper. It's flat anyway. Do you know what I mean? If you've got
paste on there you're pushing the paste away. This is going to be even coverage all the time.
So we're getting a good motion now. Just turn it round. Put your hand flat on the top of it.
If we just check it now.
Now you can see it's nice and flat. There's some previous marks here where it's probably
had a wire brush across here, a bit rough. Okay we're placing the steel rule on the edge across
the surface of the head, and we're taking that across, and we're looking for flatness in this.
Now what you can do, you can put a light on the other side, a torch,
and you'll see if there's any light coming through. We'll do it from this side as well.
That is good. You're also cleaning up this area. You can see this casting's got a few
little marks in here, but there's nothing to worry about. That's ready to go back
onto the barrel now. Right we've just put a new cylinder head gasket on. It's all put on dry.
Just make sure your level, bring this down.
For some reason it's a bit tight on the studs going down.
Now it's on we can put our bolts in. I tend to always use a bit of copper slip. As people know
it's really good on threads. It's good for chasing down the thread into the barrel on cast iron. It
means when you come to take bolts out they usually come out fairly easily. We're now going to put
the four washers and nuts on the studs. We just put a little bit of copper slip on those
and the same on the back. So we just get all the nuts back on the studs. Get the bolts back down,
just pinched up. These four top ones are bigger sockets so we'll do these first.
Just wind them down so there's a resistance.
These outer studs, four. Now we're just pulling these nuts up. Just going to change the spanner.
We can't get a torque wrench on those. But you know your pressure because it's the same torque
setting as those. So the time, if we've set the inner working out, you can feel it. Half the time
over the years these never got a torque wrench used on these. It's only when you come to do it
as an engineer that you go back to the correct settings. A lot of people wouldn't have a torque
wrench if they're working on their own bike at the weekend. They'll whip it apart, put it back
together. What I'm going to do now is I'm going to start pulling the head down properly. Just make
the reference, they always start from the middle and work out. So we start with the centre bolt. We
won't pull it up to until clicks. We just pull it up a certain way on the torque wrench. Then we'll
work diagonally. Do those other four. And then we'll do the outer ones which are on the studs.
We have to do that with a spanner. We just need to reference, to make sure we get the right torque
setting for the head bolts. So we're setting these to 29.5. It said 28 to 30. So we're just going to
pull on that one until it starts to bite. Same with this, just until it starts to bite.
That's got the first five in. Now with a ring spanner we'll carry on. Diagonally.
Right, we now start with the centre bolt. We'll pull this one down until it clicks off
at the right torque setting. Just hang on to the engine at the same time.
I'm just going to use a shorter extension.
You need to get a good hold.
We'll change the socket over and just start working now on the bigger ones.
Now use our spanner.
I'm going to run through those again, make sure we are absolutely there
so it all clicks off. Start on the centre one, the smaller socket. Hang onto the engine.
Diagonally do these.
Always have a cross pattern. Diagonally across.
Never do two on the same side. You always work from the middle out. And just pull this one down.
Just check those off again these outer ones because we are relying on what we feel is tight.
All done. So next thing really now is to put our rocket gear back in. We need to put the push rods
in. And then put the rock spindles back in place. That's coming along quite well.