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tdskip
03-23-2007, 07:18 AM
Hi guys - I'm trying to sort out the timing on the 1971 TR6 now that I've got her running again.

Paul has been a big help (thanks!), but in working through getting the timing right it appears that my damper is missing timing marks like the following;

https://i17.ebayimg.com/03/i/000/94/02/aa6f_1.JPG

Do all years have these marks? Has a DPO replaced the correct damper with an incorrect one?

Mine only has two | | marks with a tapers triangle.

03-23-2007, 07:25 AM
Mine has marks - it's a 73.

tdskip
03-23-2007, 07:31 AM
OK - did some searching. Looks like the replacement dampers from Moss don't have timing marks.

(https://www.mossmotors.com/graphics/products/PDF/837-120.pdf)

So I'm going to have to get good a timing without them.

03-23-2007, 07:54 AM
You could put a regular one next to it and engrave them...

Brosky
03-23-2007, 08:17 AM
OR.....you could buy some Mr.Gasket timing tape. Get the Ford and Chevy versions, for the 6.375" and 6.750" diameter dampers. Yeah, I know that the TR6 is 6.550", but it's as close as you're going to get and with the numbers spread across that diameter, you will be within .005" of a degree, one way or another. Coupled with the actual flex in the damper, call it "on the money".

Strip off all paint on damper to bare metal, use the center of the hash marks as ZERO or TDC and install the tape with the numbers reading out as shown in the image above, or looking at you from the drivers side of the engine. Clear coat after being done.

As I explained in the PM, this is all subjective to how you want to tune the engine. I run mine at the max, less any pinging and set the idle down to normal. Works for me and the old timers. The reading just happens to be 14-16 BTDC that works best in my situation.

bobh
03-23-2007, 08:38 AM
Another method is to calculate the length of arc based on the diameter of the damper and the number of degrees. Even though the outer edge of the damper is curved, the length of the arc per degree is so small it is reasonable to consider it to be straight.
If you choose to go this route. After you calculate the length for 1 degree you can mark the damper with a thin white line for each degree. Or as Alan mentioned scribe a line (possibly a shallow cut with a hack saw blade) for each degree. I have all the marks on my '75. I cleaned the surface then used a very fine paint brush to apply paint in each groove and number. i let it set for a few minutes then wiper it with a rag. This removed the excess paint, leaving only the paint that is in the depressed areas.
Another possibility is to apply a piece of double sided tape.(the good stuff, like what they use to hold trim on modern cars) One side to stick to a very clean damper surface. The outer side to hold a plastic or thin metal piece that has the marks and numbers engraved. Shim stock would be flexible and durable.
All of these suggestions would be best applied with the damper either of the engine or the engine out of the car where you have plenty of room to work.
BOBH

tdskip
03-23-2007, 09:04 AM
Here is what my damper looks like.

https://b.im.craigslist.org/tk/uk/GyNCDMbQJcNiGWpnaPWqOHYSUTJY.jpg

Where should the straight edge of the timing market be aligned with. I've been thinking that should be lined up with the deeper visible line. There are two, the other one is nearer the indentation.

03-23-2007, 09:24 AM
your best bet here is to do the old pull #1 plug and insert a dowel trick. that way when you rotate the engine you can feel where tdc is.

that's got to be better than relying on the marks that are there. at least you'll know it's right.

tomshobby
03-23-2007, 09:48 AM
Will this help? It is the pulley on my '76.

https://www.smithtr6.com/images/forum_pics/timing_marks_1.jpg
https://www.smithtr6.com/images/forum_pics/timing_marks_2.jpg

BTW, the white in the lines and numbers is white chalk applied and then rubbed off with my fingers.

tdskip
03-23-2007, 09:55 AM
Interesting - so if the big hash mark is TDC, the striaght timing arrow should be to the RIGHT of the hash mark?

tomshobby
03-23-2007, 10:44 AM
Yeah, I know that the TR6 is 6.550"

Assuming that 6.550 is the diameter, 20.57743 is the circumference, and 0.05715952777777777777777777777777777777........8 would then be the circumference distance for 1 degree.

So Paul's method makes great sense because it is somewhat relative anyway once your car's sweet spot is found who cares what the reading is.

Or you could easily machine the marks with a rotary indexing table.

tdskip
03-23-2007, 10:47 AM
OK - sorry for asking but should the straight edge of the timing indicator/arrow be on the left or right of the hash mark when looking at the car from the front towards the back?

Tinster
03-23-2007, 10:49 AM
My 69TR with the TR250 engine has only two marks.

d

tdskip
03-23-2007, 10:54 AM
Dale, so at TDC where are your timing marks set up?

tomshobby
03-23-2007, 11:31 AM
OK - sorry for asking but should the straight edge of the timing indicator/arrow be on the left or right of the hash mark when looking at the car from the front towards the back?

I use the straight edge of the indicator and on the pulley line if I am using a line as the mark. The important thing is to be consistent with your method.

Tinster
03-23-2007, 12:13 PM
TD

At TDC the marker arrow if straight with the
heavy cut line. That is where I had the timing
static set in the first attempts to get Crypty
operational.

The car ran at that setting but runs much better
advanced 10-12 degrees.

regards and good luck

dale

tdskip
03-23-2007, 12:24 PM
So if the heavy mark is TDC, does that make the lighter hash mark to the the left (looking down as in the picture) of it 5 degrees BTDC?

tomshobby
03-23-2007, 01:12 PM
So if the heavy mark is TDC, does that make the lighter hash mark to the the left (looking down as in the picture) of it 5 degrees BTDC?

That would be 4 degrees after. The picture is taken from the passenger side (just happened to be where the marks were) and the front of the car is towards the right of the picture. The rotation would be towards the top of the pictures so the TDC or 0 degrees would pass the timing indicator before the second mark.

tdskip
03-23-2007, 03:51 PM
OK,

So the straight edge of my mark should be a bit to the right of the heavy mark on my picture then?

tomshobby
03-23-2007, 05:23 PM
Your second picture, the one where the pulley is on the car, looks to be about 8 degrees before TDC.

tdskip
03-23-2007, 06:37 PM
Update - she only wants to run near TDC. I got her running again (yeah!) and rotated the dizzy clockwise to where she started to stumble, and then backed her off a bit anti-clockwise to where idle picked up.

Brosky
03-23-2007, 10:09 PM
Take it up to the fastest idle that you can get and back it off just a fraction of an inch. Lock it down, reset your idle and take it for a spin. If it doesn't ping under a load, it should run like a bat out of hale and you're good to go.