Author Topic: How to Extract Lash-Cap from Oil Return in 410 Head  (Read 291 times)

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Offline Old Scrambler

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How to Extract Lash-Cap from Oil Return in 410 Head
« on: October 28, 2020, 06:19:20 pm »
I found a false neutral between 4th and 5th on my C.B.R. because I had different boots..........really over-rev'd but thankfully had minimal damage when 2 adjuster-nuts came loose. The oil-return on the intake between 1 & 2 is just over 6mm in diameter. It reduces to a much small hole near the bottom. The lash-cap fell in and is laying side-ways. It is loose but I can't seem to get a small 'pick' to tip it and pull it out. Oil seems to pass as I ran the motor under load with no problems.

I am attempting this with the head on the motor. I'm not sure if removing the head will offer much help due to the small diameter of the lower hole. My smallest magnet is a little to big to fit in the hole. I thought I would ask here before I ask the local bike-shops for help.  :-[
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
CB750 Classic Bonneville Racer thread - http://forums.sohc4.net/index.php/topic,135473.0.html
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Offline scottly

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #1 on: October 28, 2020, 06:49:36 pm »
I have some really small diameter magnets that I have used for pickups for speedos and such. I have also used a strong magnet attached to a screwdriver or drill bit to get down into tight sports; the screwdriver shaft conducts the magnetism.  How deep in the hole is the lash-cap?
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Offline dragracer

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #2 on: October 28, 2020, 09:13:35 pm »
Is there a way to use compressed air from the bottom of the passage and leave a magnet near the top to catch the lash cap when it blows upwardss??

Offline jgger

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #3 on: October 28, 2020, 09:45:11 pm »
Could you use a length of fuel line and tape it to a shop vac?  I have a micro set for my shop vac that is pretty small, got it at home depot.  If regular fuel line is too big then chain saw/ weed Wacker line is really smaller.
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Offline Old Scrambler

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #4 on: October 28, 2020, 10:01:17 pm »
All are worthy suggestions.........I have considered a dab of epoxy on a pick and set it in the hole to attach to the cap.......but afraid of other damage. We shall see what happens in the next few days.........new lash-caps should arrive to go with the new hard-welded rockers and Ti-nuts..........If all works out, the local dyno will be getting a test before Christmas.......
Dennis in Wisconsin
'64 Triumph Cub & '74 Honda CB750 Bonneville Salt Flats AMA Record Holder (6)
CB750 Classic Bonneville Racer thread - http://forums.sohc4.net/index.php/topic,135473.0.html
'63 CL72 Project(s)
'66 CL77 Red
'67 Triumph T100C
'73 750K3 Owned since New
'77 750F2 Cafe Project
2020 ROYAL ENFIELD Himalayan

Offline PeWe

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #5 on: October 28, 2020, 11:53:46 pm »
Hard piano wire with a bend that can be inserted beside and under the lash cap and pull it up ? 
Be careful so the wire will not snap and fall down.
Hold a magnet above to catch it so it will not orient different and fall .....

Use of fishing hook might be better....

Offline johno

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Re: How to Extract Lash-Cap from Oil Return in 410 Head
« Reply #6 on: November 01, 2020, 03:55:48 am »
easiest way is to turn bike upside down.  I had a spark plug jam in head on me and turned bike upside down, BAM plug fell on the floor after hours of frustrating attempts with every tool known to man.  ;D
ciao
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