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MG TD TF 1500 - Pushrod ends

Hi guys,

I see a lot of correspondence about push rod lengths, but does anybody have the details on the ball and cup ends. I don't have any gear to accurately measure the curvature.

Regards Bernie
B W Wood

Bernie the cup is 10MM as are the ball end of the push rod
Len Fanelli


Bernie,
I just had the Smith Brothers make me a set of pushrods and they requested I send them an existing pushrod so they could accurately measure the socket and ball end. I also sent with it a tappet and an adjustment bolt for reference.
That seemed to solve the size question. However, Len is probably correct with the 10mm statement.
As for length there are two measurements. Actual and the important one "Effective length” This is obtained by putting a ball bearing the size of the socket (10mm?) into the cup of the pushrod and noting the overall length measurement. Then subtract the Dia of the ball bearing.

Rod

Rod Jones

I always thought that the difference in push rod lengths was in thousandths of an inch. If that is true then I assumed that any difference in rod length can be accommodated by the adjusting screw. Please correct me if I am wrong which will not come as any surprise.
Jim Merz

I am trying to get Smith Brothers to make me a new set of pushrods to use with Roller Rockers. The replied saying they had conflicting information and did not know what was original. They wanted me to send more info on the ball and cup or a sample, but i don't have the gear to measure the radius. I told them that the ball is 10mm diameter, but to be it does not look like a 5mm radius, but flatter? Either way I am away from home for the next two weeks and was trying to keep this moving, and avoid sending sample from New Zealand to the states. A lot of people on this site seam to use them so I am surprised they don't know the standard ends.

And before anybody suggest I shorten mine, I did try and ended up destroying two of them.

Rod,

I presume that you send the original parts, do you have and order or delivery docket number I could quote, and say make mine the same as your?

Bernie
B W Wood

Bernie, Please contact me ASAP!
Len Fanelli
914 420 8699
laf48@aol.com
Len Fanelli

Bernie,
I hope Len can give you the info you need re the length and ball and socket info.
My work order would only be of use for the socket end that fits a STD tappet (Cam Follower) and Tappet adjusting domed bolt of a STD rocker. (My Current equipment)
Not sure it will help you?
Also, my pushrods seem to be shorter than the short ones sold by Moss for their Crane Cams..... My head it would seem has been skimmed to the max - hence the rods are shorter to keep the geometry correct.
I would hope Len can give you the dimensions you need to get the right set up form Smith Bros; I believe from another post here he has an adjustable pushrod he could possibly lend you - to get the correct length for your install.
I was very pleased with the work S.B. did for me and the rods are in and working fine.
Rod.

Sales Invoice No SI-58941 9/3/2014 25267
Account Rep Pierre C.
Rod Jones



Jim,
Re the length of the pushrods?
Bud Krueger put me wise on the measurement of my head - which appears to be 2.865" or 72.77mm. About as far as you should go removing material wise. (PO not me.)
I do not have any spacers under the rocker shaft towers and the tappet screws (domed adjustment bolts) are the long ones. I thought it was STD.
My pushrods which came with the car in 1974 are 8 3/8" in length (physical length) Nothing like the length Moss are selling for their Crain Cams 8.531¡¨. Way more than a few thou.
I guess with only 0.237" lobe lift and the rocker valve end going down 8mm (per the book) It should not matter that much. But there must be an optimum length that gives the best position of the pushrod in the tubes through the head. Possibly giving even pressure on the tappet socket which may help it to rotate?
For what it is worth my tappet adjustment screws are in about the middle of their range, position wise, set at 12 thou hot.
My Tappets were not rotating from the signs of the wear when removed. All of the tappets were the same size when measured with an electronic caliper. None appeared tight in the bores. So if the cam is in the right position (off set a tad to the tappet, visible when looking down the bores) something must be preventing them from rotating?
Looking at the geometry of the cam to valve it is not a strait push. A tenth of an inch in pushrod length either way should not make that much of a difference.
Unless I am not seeing the full picture. As usual ļ
Rod


Rod Jones

Rod,

Thanks for that, it is the STD ends I want, and it is Pierre I am in contact with so I will give hime that number and get a set ordered.

Thanks Bernie
B W Wood

This thread was discussed between 01/10/2014 and 02/10/2014

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