Milwaukee Midget

[Dr Goggles]

. . . and as I couldn't get to sleep, I went ahead and assembled the pistons and rings.

I've done a lot of different things when I couldn't sleep, but that ain't one of them.....actually,no-one who knows me would trust me to assemble a motor in even my most lucid moments, let alone in a moment when I should be akip.

I'm loving watching though, Lilliput engine reconditioners.

[Milwaukee Midget]

Well, as long as we're making oblique references to old television shows –

Hey Bronze Fonz ,we're talking holy words here I don't want you "general-izing"....

Yep, the world's second most famous Triumph rider, right here in HD’s back yard.  Now that's a rebel without a clue . . .

MM;
"I am not a number, I am a free man!"  .....from "The Prisoner", right?
Regards, Neil   (San Deigo, CA)

We have a winner.  Always been a fan of that show.  To the point that I’ve incorporated the font used in The Village on my new decals –

[grumm441]

.....actually,no-one who knows me would trust me to assemble a motor in even my most lucid moments, let alone in a moment when I should be akip.

Yup
G

[Milwaukee Midget]

I'm loving watching though, Lilliput engine reconditioners.

Hmmm . . . And here I thought that the Lilliputians specialized in full body restraint and containment systems.  

Pistons, rods, crank, cam - in place.  Off work Thursday - I'll throw the head on and see how much I can shave.

[Milwaukee Midget]

Stop.

Take a break.

Walk away.

Think it through.

Exhaust valve in #1 hits the piston.

Take a break.

Think it through.

I'll be back.

[Tman]

Stop.

Take a break.

Walk away.

Think it through.

Exhaust valve in #1 hits the piston.

Take a break.

Think it through.

I'll be back.

Good thing to find now rather than fireup!

[Peter Jack]

They probably all do then or at least come pretty close. It should be a pretty simple machining operation to provide clearance.

Pete

[Milwaukee Midget]

They probably all do then or at least come pretty close. It should be a pretty simple machining operation to provide clearance.

Pete

PJ, you're always the voice of reason - thanks.  I'm thinking now it might not come to that - I'm thinking operator error.

I needed to walk away from it for today.  6+ hours and two trips to the hardware store was enough. 

Here's the deal -

I'm pretty darned certain that the new timing gear set - an adjustable piece with a timing mark only on the crank gear - and my lack of understanding of it - is the source of the problem.

I wanted to get it close and I used an old timing gear on the cam - one with a mark - to get the cam approximated, then replaced it with the vernier unit.  Using the stock cam sprocket, I lined up the centers and the dots. 

What I did not check is where the timing mark on the original stock crank sprocket was indexed with respect to the keyway.

I may have jumped the gun, and I'm hoping it's just a brainfart.

Time to grab the spec sheet and do it right - but . . .

One variable hanging over my head that I've yet to suss out is what a 2.45:1 rod/stroke ratio might contribute to my headache.  This cam opens mighty fast, and I've got to lose about 2+ cc's from my combustion chambers to make this combination really work right.

The upside is that the rocker geometry looks pretty decent on the intake stroke.

Finished up a recording tonight - my guitar and organ parts, anyway.  Nice to get away from the Midget for a couple of hours.

"Snap-On Fool" is the song.

I feel pretty close to that song . . .

[Anvil*]

Exhaust valve in #1 hits the piston.

Mmmm, on my MGA all the exhaust valves hit the block. I had to eyebrow clearance each cylinder and then blend a ramp into the piston.

If it's just #1 the others are likely close plus one seat is likely a bit proud. You'll want to check the depth of all four tubs and the seated height of all your valves. If it's still just one cylinder you'll need to check cam lift and the ratio of that one rocker.

[Milwaukee Midget]

Okay, the indexing between the stock and new sprockets is not the same.  
Rule # 1 – MAKE NO ASSUMPTIONS.

Mmmm, on my MGA all the exhaust valves hit the block. I had to eyebrow clearance each cylinder and then blend a ramp into the piston.
 

Hey, Anvil* - Were you putting a MkII head on a 1500 block?
 
No block clearance issues here, it’s definitely the piston.  I’m going to just start from scratch with the dial indicator, keep the specs in front of me, jot down numbers and figure it out.  Part of the problem is the timing events are splayed in such a way as to maximize intake on the shared ports.  This means that 1 and 4 have different timing events with respect to their pistons than 2 and 3.  Advancing or retarding the cam is not an option – all events are maximized with it straight up, and while advancing or retarding it may help 1 and 4, it will be at the expense of 2 and 3.

Absolutely no margin for error – this has to be spot on.

[Anvil*]

Hey, Anvil* - Were you putting a MkII head on a 1500 block?

No,  the bathtub on the exhaust side with a bit of the valve is over the cylinder edge as built. Valve came within .002" so it needed a bit more clearance to avoid unhappy sounds.

[Milwaukee Midget]

Okay – maybe I found the problem –

First off, I nailed down TDC with a piston block – the right way to do this.  Still, I was only 1 degree off from the dial indicator method.   You grab what you can, where you can.

With TDC confirmed, I then found max lift on the #1 intake.



Which is 5 degrees off of where it’s supposed to be – 102 degrees.





I’m already at the stops on the sprocket – So now, pull the sprocket, bump it a tooth, and try again.

A job for Sunday.

[Milwaukee Midget]

Wait a minute - let me look at that again.

[Anvil*]

Wait a minute - let me look at that again.

Just as a check I like to use the points on either side at .050 and .100 and compare that to where open and close events are supposed to be on the cam chart. Hopefully the centerlines and the open/close events will sort out soon for all four cylinders.

[Milwaukee Midget]

Anvil* - Got it - same idea as calculating TDC = the average should be the lobe center.

Tedious work. 

I wish I were quicker at it.