Heart Transplant

[Fast Eddie]

What does ‘set to spec’ mean tho swoosh?

Do we mean ‘factory’ / ‘stock’ spec?

Maybe they set the spring heights to stock spec?

By very definition, there’s no way you can cut that much metal from the seat area in a ‘stock’ head and it still be to ‘stock spec’ ?!

 

[swooshdave]

Val

What does ‘set to spec’ mean tho swoosh?

Do we mean ‘factory’ / ‘stock’ spec?

Maybe they set the spring heights to stock spec?

By very definition, there’s no way you can cut that much metal from the seat area in a ‘stock’ head and it still be to ‘stock spec’ ?!

Spring and valve height.

 

[Fast Eddie]

If the seats have been cut, the valve heights MUST be different to stock.

So I would suggest your man means that he shimmed the valve springs accordingly in order to get the spring height BACK to spec after cutting the seats.

 

[comnoz]

Well, springs can be shimmed and you can get away with a lot of extra valve stem height, Black Diamond valves are not normally shortened but you may need to shorten the pushrods.

And it's likely that the loss of compression due to the sunk valves is a good thing on a Combat head.

 

[gortnipper]

Head was sandblasted, not sure what media they used.

Cases were vapor blasted. I'll try to see what happens when I wipe them down.

After all my parts were vapor blasted (glass media) I washed them with a mild detergent and hot water with bristle brushes and hole brushes, then 2x pressure washed them to rinse.

 

[swooshdave]

After all my parts were vapor blasted (glass media) I washed them with a mild detergent and hot water with bristle brushes and hole brushes, then 2x pressure washed them to rinse.

Yes, planning on washing the parts.

 

[swooshdave]

 

[swooshdave]

Need to put this back in with the hole down.

.022" Perfect.

Last dry fit. New hardware made for a lovely presentation.

 

[swooshdave]

Sealed up and ready for the next step, getting all the timing side stuff on. I almost got the cam washer in wrong. Luckily I checked the manual and it said flat side against the case.

 

[swooshdave]

Got the engine back in the frame last night with the help of MikeT. Of course it all got filmed so it took twice as long but at least we can share the video later. In my excitement to get the engine back in I forgot to put the breather on. Better now than after the head was on! I think I can remove the bolts except one and rotate the engine up to get to the back of the engine. I also didn't put on the oil junction block. I'm not sure if that can be put on with the engine in place either.

Anyways, getting closer!

Head still needs assembled as the rockers are still out. And then hoping the rocker geometry is ok. I have a feeling the engine is still going to take a while.

 

[Brendan S]

The oil junction block has enough clearance if you have the bolt in it first.

 

[swooshdave]

The oil junction block has enough clearance if you have the bolt in it first.

Good to know, I have to move the engine to get the rear breather on anyways.

 

[swooshdave]

Video of me checking the end float.

 

[swooshdave]

Note the correct pre-MkIII oil pump seal. Fits snuggly.

Timing side sealed up.

Main seal installed. I didn't lube it properly so I'm going to push some assembly lube in there. The drive side crank looks ugly but I cleaned it up the best I could. I've pre-fitted the front pully and rotor so they fit nice.

 

[swooshdave]

Primary all done. Barrel, oil tank and head still to go. The head is my biggest worry, probably because it's the most complicated.

 

[baz]

Primary all done. Barrel, oil tank and head still to go. The head is my biggest worry, probably because it's the most complicated.

What is complicated about fitting the head? Do you mean locating the pushrods?

 

[swooshdave]

What is complicated about fitting the head? Do you mean locating the pushrods?

I'm concerned that because it's a Combat head there might be complications in the geometry if the valves weren't set up correctly.

It might be a lot of worry about nothing.

 

[baz]

Yes depending what length pushrods you have IE if they a combat length you may have to adjust them
You can prize the ends off and shorten them
You may have the head on and off a few times getting it right
I'd also do away with the Thackeray washers and shim the rockers for best valve contact

 

[swooshdave]

They worked great before. If everything just goes back together I won’t have any worries.

 

[Fast Eddie]

Wudda been a doddle to check valve geometry and have the head on and off as many times as you like whilst the engine was on the bench.

Now the bottom end is in the bike you really do need to hope it’s all ‘right first time’.

Personally, I prefer to assemble the top end on the bench, yes, the engine is a bit of a heavy lump, but I prefer that to pissing around with the head in the frame personally.