1933 ten, valve grind

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Rod
Posts: 37
Joined: Sun Nov 24, 2019 9:44 am

Re: 1933 ten, valve grind

Post by Rod » Sun Nov 29, 2020 8:45 am

Yep, I've never found it easy to get small diameter faces square even with the figure-of-eight technique [hence the 'you're keen' comment]. The other way I've heard of facing the adjuster screws, is to set up the screws in an x-y vice [even a cheap one] and using a mounted stone in the chuck [with the drill press on high speed] to dress them, using the x-axis feed and the quill feed, making sure the stone strokes off the side of the screw head by 1/2 the stone diameter.
The opposite way around if you know what I mean.

GaryCullen
Posts: 30
Joined: Wed Nov 20, 2019 1:34 am

Re: 1933 ten, valve grind

Post by GaryCullen » Wed Dec 09, 2020 11:23 pm

Hi All,
as promised a quick update.
New Valve guides arrived.
The inserted end of the new guides looked quite sharp and I thought they may get stuck going in with the drift so I mounted each in my lathe and very slightly rounded off the sharpness with a fine file. Then into a zip lock plastic bag with some oil and into the freezer.
The old ones drifted out okay. I may have mentioned this in an earlier post.
Cleaned the guide holes with some petrol, nothing much came out.
Using the same drift but with a brass collar at the impact point I drifted the "frozen" new ones in.
I have a small hole drilled through the drift at right angles with a pin inserted to show me when 1/1/8" insertion depth is reached. The pin impacts the Engine Block surface when the guide is at the correct depth.
Freezing the guides worked well and they all went in without trouble.
Next job was to cut new 30 Degree and 60 degree bevels in the valve seats. Then lightly re cut the 45 degree valve seating contact area. I managed to reduce the contact area to about 1/8" on all the exhaust seats.
Then hand ground all valves using coarse, medium then fine grinding past.
The valve stems went into each guide without interference so the brass collar on my drift did its job and did not distort the top of the guides.
Tappet adjusters all back in and wound right down, then the new valve springs and collars.
Then I have discovered that the pins for each Exhaust valve need replacing as the ends are distorted and won't push in smoothly.
so now I wait for some new pins to arrive...
more later.

cheers
Gary
Auckland VAR
NZ

Because I am not a member of the ATDC I cant post pictures but if a member wants to do this I can email some pictures particularly if the valve guide drift tool with brass collar and insert depth tool I made. might be helpful to other ATDC members.

GaryCullen
Posts: 30
Joined: Wed Nov 20, 2019 1:34 am

Re: 1933 ten, valve grind

Post by GaryCullen » Wed Dec 23, 2020 7:32 pm

Further progress....
All valves are now in and gapped.
New head gasket lightly greased with copper grease and ready for the head.
Then thought I would check the head with a steel straight edge for flatness first and discovered I have a slightly banana shaped head.
Both ends , front and rear show light under the straight edge. So off to the engine recon place for a skim.
While I wait for this to be done can anyone advise what is the recommended Torque setting for the head nuts?
None of my Austin manuals actually state a setting, just advise to pull down the head evenly following the pattern in the manual until tight.!
Then re-tighten after 250, 500 then 1000 miles.
From past experience with cast iron blocks and heads I would assume the torque setting is in the 30 to 35 foot/pound area.
Anyway Merry Xmas to all Austin 10/4 drivers and I hope you get some sort of family gatherings underway in the UK to celebrate.
we are pretty fortunate in NZ with no restrictions presently

Cheers
Gary
Auckland VAR.

bob_allison
Posts: 262
Joined: Wed Nov 27, 2019 3:20 pm

Re: 1933 ten, valve grind

Post by bob_allison » Thu Dec 24, 2020 12:16 am

Just don't use a long spanner , and your wrist should tell you .

Rod
Posts: 37
Joined: Sun Nov 24, 2019 9:44 am

Re: 1933 ten, valve grind

Post by Rod » Sat Dec 26, 2020 2:42 am

Hi Gary, good to hear the end is in sight...
I have a copy of a page of the Austin Service Journal which quotes a value for a 3/8 BSF head stud [Big Seven, Ten, Twelve, Fourteen and Eighteen] of 550 in/lbf which converts to 45 ft/lbf.
However this question has been asked before-on December 27, 2014 oddly enough-as part of a general enquiry for torque settings by a guest who was rebuilding a 12/6, and the advice from the ATDC Technical Writer was similar to Bob's.
I can't search and/or copy & paste the exact text, so I will quote it [omitting some of the preamble and the warning about pulling out head studs], usual disclaimers about advice given in good faith etc. :)
"Torque settings, we [ATDC & Austin works] do not recommend the use of a torque wrench on these engines ......... The Austin factory recommendation was an 8-inch ring spanner, working in the recommended sequence, and every three nuts returning to the beginning re-doing each nut in turn. Always bring up the nut and 'feel' the load, then slack off one flat and re-do up"........
My understanding is the retighten several times at X mile intervals was more applicable to the original copper-asbestos gaskets which could have inherent variable compressibility. You may get different results with a more modern gasket, my suggestion would be to use your discretion about how many times you re-tighten, certainly the initial retighten would be advisable.

Old Bertie
Posts: 10
Joined: Fri Feb 14, 2020 2:01 pm

Re: 1933 ten, valve grind

Post by Old Bertie » Sun Dec 27, 2020 6:53 pm

My understanding was that Leaded Petrol was not available in the UK before 1940 when it was first imported from the USA in small volumes. If this is correct then our Austin 10 side valve engines were designed to run on what we now call unleaded petrol because that is all there was and there is no need for hard valve seats. In fact I know of at least one case where hard valve seats have were fitted by milling out the block and inserting hardened seats which then cracked up and virtually destroyed the engine. I also remember driving with Benzole as a fuel which was derived from Coal Gas.

4000 to 7000 miles is quite good for perfect valve seating but remember these old style side valves will run and run and I have known engines at 35000 where the seating is a reasonable fit. The main issue is the problem of modern ethynol fuels and the variable quality of Supermarket petrol.

I agree with the point on Torque wrenches. Some years ago my wife purchased as a birthday gift (at huge expense) a torque wrench with a digital reading. I have never used it as the minimum setting is twice the maximum that should ever be used on a pre-war engine. I was taught to use an 8" ring spanner of the correct size and when you cannot turn the nut any further that is the correct torque setting with the proviso that you tighten the nuts in the correct sequence.

I also use an eggcup full of two stroke in the fuel when the car is stored over the winter to protect from corrosion in the tank.

GaryCullen
Posts: 30
Joined: Wed Nov 20, 2019 1:34 am

Re: 1933 ten, valve grind

Post by GaryCullen » Sun Dec 27, 2020 7:27 pm

Thanks for the replies and advice all.
Very much appreciated.
I will leave the torque wrench in its case and do it the traditional way by hand.
I have a set of suitable 8 inch ring scanners and plan to put the head back on later today.
Cheers
Gary
Auckland VAR

GaryCullen
Posts: 30
Joined: Wed Nov 20, 2019 1:34 am

Re: 1933 ten, valve grind

Post by GaryCullen » Wed Dec 30, 2020 7:47 pm

Update:
Head back on and tightened down using the 8 “ ring spanner and sensing tightness by feel.
Surprisingly I think I have all the nuts about right. I applied a small amount of copper grease to the stud threads and the nuts pulled up tight easily.
The test for the success or otherwise of this whole valve grind exercise is to improve the compression ration from below 40 to somewhere around 90.
I did this without the manifold on the engine and “cold” of course.
Using a screw in compression gauge and turning over the engine on the starter I got the following for cylinders 1,2,3 and 4:
91:90:78:91.
Mmm, not sure why number 3 is a lot lower but I have decided to leave it and see what it is after a few miles.
So thanks to all who offered advice for this project.

Cheers and a happy new year to you all.
Gary
Auckland VAR

simonbradford
Posts: 63
Joined: Fri Nov 22, 2019 8:56 am
Location: Sleaford

Re: 1933 ten, valve grind

Post by simonbradford » Thu Dec 31, 2020 9:09 am

Try a little oil down No3. If the compression rises it could be the rings.
Regards
Simon

GaryCullen
Posts: 30
Joined: Wed Nov 20, 2019 1:34 am

Re: 1933 ten, valve grind

Post by GaryCullen » Thu Dec 31, 2020 7:41 pm

Thanks Simon,
Yes I suspect the next exercise will be a ring job. After the engine is warm there is some bluish smoke from the tail pipe.
Can’t be the valve guides as I have installed new ones and new ex valves!
Cheers
Gary
Auckland VAR

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