There was a clue earlier in the thread but I was sworn to secrecy at penalty of forum banishment.
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XS1B Engine Teardown
- Thread starter Jim
- Start date
There was a clue earlier in the thread but I was sworn to secrecy at penalty of forum banishment.
A day late...
The Amazon guy that is. And bonus, found my lapping compound while hunting for thread locker... big bonus!
Didn't find the ball gauges, but the Amazon dude dropped these off as well.
Cheap Chinese, 15 bucks and change if I recall, but they'll get the job done.
So... tackled the the huge hole first. Book calls for an 8.5mm drill bit for a M10 X 1.5 tap. That cleaned up prolly 75-80% of the mess the PO made, so I went ahead and tapped it.
Didn't get pics of the hole or threads... sorry.
This was what I was hunting when I found the lapping compound, Permatex Hi Temp stuff. Don't recall... 600°f maybe?
Ran it down 'till it stripped, then backed it off a half a turn... jus' kiddin'... Ran it down until it felt about bottomed and called it good.
Next up was the partner with the stripped threads. Drilled, tapped, helicoil.... yada yada...
And just for good measure... works.
Next up, the plug hole that me and the PO screwed up. Tell ya what, if I ever found the dude that thought to put a tap, on top of a tap, with a cutting bit in-twixt, I'd buy him a beer.... hell, two beers.
As long as you have enough threads left (we did) and keep your wits about you, it taps true every time.
I was gonna recheck my guide clearances again, now that I have some ball gauges (again), and lap and install the valves, but I took a toke a bit ago... and seem to have lost a bit of steam... oh well....
The Amazon guy that is. And bonus, found my lapping compound while hunting for thread locker... big bonus!
Didn't find the ball gauges, but the Amazon dude dropped these off as well.
Cheap Chinese, 15 bucks and change if I recall, but they'll get the job done.
So... tackled the the huge hole first. Book calls for an 8.5mm drill bit for a M10 X 1.5 tap. That cleaned up prolly 75-80% of the mess the PO made, so I went ahead and tapped it.
Didn't get pics of the hole or threads... sorry.
This was what I was hunting when I found the lapping compound, Permatex Hi Temp stuff. Don't recall... 600°f maybe?
Ran it down 'till it stripped, then backed it off a half a turn... jus' kiddin'... Ran it down until it felt about bottomed and called it good.
Next up was the partner with the stripped threads. Drilled, tapped, helicoil.... yada yada...
And just for good measure... works.
Next up, the plug hole that me and the PO screwed up. Tell ya what, if I ever found the dude that thought to put a tap, on top of a tap, with a cutting bit in-twixt, I'd buy him a beer.... hell, two beers.
As long as you have enough threads left (we did) and keep your wits about you, it taps true every time.
I was gonna recheck my guide clearances again, now that I have some ball gauges (again), and lap and install the valves, but I took a toke a bit ago... and seem to have lost a bit of steam... oh well....
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This is kinda scary....
hmm never noticed that tight "overlap" before....
hmm never noticed that tight "overlap" before....
That's close to not sealing at the spark plug. Has it been refaced in the past, or have I just never noticed how close that is?
Bunch of random plug hole detail pics from the SOIR
last one is from a 71 head.
last one is from a 71 head.
Variable is the answer. But the one posted before is either an outlier or has been refaced, it seems.
I believe that's the hole he helicoiled...
My guess is it's an early head thing. Looked at several 447 heads and they all look like your previous 8 pics, Gary.
last one is from a 71 head.
The other plug hole looks like the '71 head above.
Here's a better shot of the reworked hole.
...and the other hole.
When you take into account the thread insert, they're about the same. I recessed the threads ever so slightly so I could put a spot facer on the mating surface. But we're just talking a smidge to clean up the mating surface. Any more would start to alter the plug reach... and the attended can of worms that could possible open.
The only spot facer I have that's big enough is a back spot facer... so I'm still working out how to tool up for that..
When it's all said and done, there should be the same 2.5mm of sealing surface on both sides.
Anyway, good eyes both of you. I've always believed there's no such thing a too many eyes when inspection time rolls around.
Well since you mentioned it...
Postman woman delivery just now.
Post
A little birdie sez dunk, excercise those sockets in solvent. see if any grit comes out.
mrriggs
XS650 Junkie
Thanks Bob, Mrriggs.
So it looks like they changed the machining and/or casting between the XS1B and the XS2.
So it looks like they changed the machining and/or casting between the XS1B and the XS2.
I seem to recall you don't have a Bridgeport or any type of mill.The only spot facer I have that's big enough is a back spot facer... so I'm still working out how to tool up for that..
What you could do though is machine a bushing that fits inside the spark plug hole and has maybe a .001" clearance on diameter for the shank of the back spotfacer.
I had a job once that I needed to backface a bolt pattern on a casting. It took a little extra programming, but I was able to get the machine to go to the hole location (after I drilled it, obviously), do a plunge move to send the shank thru the hole, and stop. I then had to attach the cutting bit and hit the cycle start button. The machine would turn the spindle on and raise the head up to face the hole, then drop the head again and stop so I could take the bit off.
Hit cycle start again and the head would raise the shank out of the hole and go to the next hole and repeat the process.
I only had two castings to do, but each one had 16 holes or some shit, so I was kinda a pain. But I basically told the machine to go to a hole location and run a subprogram at each hole to do the stoppy starty bullshit.
Aaaaaanyways, if you make yourself a bushing (or a sleeve that's pretty much the length of the shank minus the width of the cutting bit and a little room for a drill chuck), then you can probably just use a hand drill if you clamp the head down. Go slow and use plenty of WD-40.
Just my
.
Yes. Always interesting to find differences between 70-71 engines and later years. Good eye.
It's taken me all day to figure out what y'all were discussing. This pic is my free XS1B (ignore the arrow). I have a 1972 and a 1973, neither is like this.
Appears to me to totally be a non-issue. My spark plug washers make full contact. Just barely.
Rechecked the valve guides with a mic. and ball gauges. Slight variations, but all clearances still good.
Took the broke plug I turned into a thread chaser and turned it into a bushing for the spot facer. 3/8" shaft, so I used the Atlas to run a 3/8" bit through it.
Screwed it into a plug hole and discovered my 1-1/4" spot face is just slightly too big.
Had to take about 20 thou off before it fit. Drill and disc sander made quick work of it.
Smooth sailing after that. Both plug hole faces cleaned up nicely. Some very slight chatter, nothing to worry about though.
Plum tickled I is, couldn't have asked for it to go any better.
Now back to the overlord. Maybe she'll let me do the valves tomorrow...
Took the broke plug I turned into a thread chaser and turned it into a bushing for the spot facer. 3/8" shaft, so I used the Atlas to run a 3/8" bit through it.
Screwed it into a plug hole and discovered my 1-1/4" spot face is just slightly too big.
Had to take about 20 thou off before it fit. Drill and disc sander made quick work of it.
Smooth sailing after that. Both plug hole faces cleaned up nicely. Some very slight chatter, nothing to worry about though.
Plum tickled I is, couldn't have asked for it to go any better.
Now back to the overlord. Maybe she'll let me do the valves tomorrow...
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All 4 valves are lapped in. Nice purty solid grey ring on all 4 seats and valve faces. Went ahead and put a little shine on the combustion chamber. Theoretically that cuts down on carbon buildup,,, 
Cleaned everything (again) to within an inch of it's life........... and where the fuck are my guide seals?
I've got 3 or 4 sets here somewhere... but where the hell is somewhere.... 
If I ain't found 'em by the time the rings hit the Cali coast, I'll order more... fuck me I need a better file and stocking system.
Cleaned everything (again) to within an inch of it's life........... and where the fuck are my guide seals?
I've got 3 or 4 sets here somewhere... but where the hell is somewhere.... If I ain't found 'em by the time the rings hit the Cali coast, I'll order more... fuck me I need a better file and stocking system.
They're somewhere for safe keeping. That's where all my bits are too.
