Trunnions (again)

[Dave Herrod]

Apologies for raising this issue again, but I would be grateful for some advice as it seems that I have a pair of trunnions with the oposite problem to that discussed previously and don't know whether it is worth fitting them.

 

On inspecting the trunnions from my car before putting the suspension back together, I noted that the pins on both were badly pitted and corroded and, even with a good clean up, were really not going to work particularly well. As I was going to be nearby, I called into the TR shop to pick up a new pair the other day.

 

In light of all of the discussion, I wanted to check that the trunnions fitted the vertical link whilst still at the shop. Using a NOS stanpart link, the new trunnions ran up the thread very easily but there was discernable play, in as much as you could feel the trunnion rocking on the VL. Not good, thought I, but I didn't really know how much movement is to be expected. Clealy, given the pitch of the thread and the fact that it isn't screwed up tight in the way that a nut and bolt, for example, would be, there must be some relative movement between the two parts. In an attempt to shed some light on the issue, we tried the same exercise with the same NOS link and a NOS trunnion that they had. This too exhibited some play. I should add that this post is, in no way, intended as a criticism of the TR shop, who were very accommodating and eager to help find the right solution.

 

Can anyone comment on how much relative movement between a trunnion and link can be expected. One of the ones off my car felt pretty solid whereas the other had more movement, albeit less than the ones I looked at today. Obviously, the ones off the car are full of grease whereas today's specimins were dry.

 

I note that Revingtons advertise the trunnion pin as a separate part. Does anyone have experience of replacing the pin? I assume that there is a risk of deforming the brass shell during the process.

 

Comments and advice greatly appreciated.

 

Cheers,

 

Dave

[Dave Herrod]

No advice?

 

what have I said?

 

Dave

[BlueTR3A-5EKT]

As you have described this post as Trunnions (again), I think you have answered your own question.

See this thread http://www.tr-register.co.uk/forums/index.php?showtopic=34414

 

No, I would not expect there to be any obvious movement between the trunnion and V post when new.

The WSM tells us that the V post thread <<Clearance on effective diameter when screwed into part no. 200438 (trunnion) to be 0.002" to 0.008">> That is not a lot of wobble.

 

Trunnion pins - if they have glass hard threads do not buy. If you do get them pushed into your old trunnion the thread may well distort. I have just had a quote to remake a TR trunnion tap from an American company as strangely I could not find a UK co willing to quote. The price of $92.07 is a good strting point if the register is considering adding such an item to its 'Loan Tools' stock.

 

QUOTE

 

The following is our quotation:

 

(1) qty. Our P/N 48846

 

13/16-10 H4 4 Flute Bottoming Tap (for tapping part of the way thru, then backing out)

 

$92.07 each

 

Delivery: 2-3 work days to manufacture

_____________________________________________-

 

(1) qty. Our P/N 48845

 

13/16-10 H4 4 Flute Plug Tap (for tapping all the way thru a part)

 

$92.07 each

 

Delivery: 2- 3 work days to manufacture

 

*Note: We only recommend tapping twice the diameter of the tap, which for this size is 1 5/8". No guarantee, no return for tapping a depth of 2".

 

 

*NOTE: DELIVERY TIMES are as of quote date and may vary on date of placed order. QUOTES ARE VALID FOR 30 DAYS. WE ACCEPT VISA, MASTERCARD, AMERICAN EXPRESS, OR DISCOVER. WE DO NOT ACCEPT WIRE TRANSFERS OR PAYPAL. TAPCO RESERVES THE RIGHT TO OVER OR UNDERSHIP BY 10% ON SPECIALS. THERE WILL BE A 10% EXTRA FEE ADDED FOR EXACT QUANTITY REQUESTS. SPECIAL MANUFACTURED ITEMS IN PRODUCTION WILL NOT BE CANCELLED. CANCELLATION FEES MAY APPLY IN SOME INSTANCES.

 

Regards,

Julie Nelson

 

 

Tapco USA, Inc.

5605 Pike Road

Loves Park, Illinois 61111

U.S.A.

Toll Free Ph: 800-827-7787, Direct: 815-877-4039

Toll Free Fax: 800-827-6343, Direct 815-877-6143

 

REQUEST

 

-------------------------

 

1) Custom Made Taps and Dies

 

 

 

Selected Options

 

=

Please fill out as much Information as possible

 

Need = TAP

 

If Tap, Style = Bottoming

 

If Die, Style = Chasing threads

 

Type = Thru Hole

 

Depth of hole if known = 2 inches

 

Material = brass

 

Size/description = 13/16 NC * 10 tpi

 

Class of Fit = tight

 

 

 

 

 

Originating Page

 

----------------

http://catalog.tapcotaps.com/category/all-categories-special-taps?&plpver=10

 

 

 

Message From Sender

 

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The tap is to clear a brass suspension trunnion thread that fit to a front suspension steering king pin on a classic 1950's car. The thread form the swivel part of the steering and must be a tight but running fit.

 

[Dave Herrod]

Thanks Peter,

 

I raised the issue again because the trunnions I have bought appeared to be loose as opposed to the general problem discussed in the previous post of them all being too tight. The fact that what was supposed to be an NOS trunnion and V post also exhibited a degree of play made me wonder how good a fit to expect. You have now answered that and it's clealy time to try and find another pair.

 

Dave

[MCOOPER53]

Dave,

 

I'm just in the process of re-assembling the front suspension on my 3A, replacing the inner bushes only, but when putting it back together I did notice some lateral movement on VL/trunnion, but when the suspension was fully assembly this movement had gone. It must be due to the top wishbone assembly holding the VL in position. I think in an ideal world there would be lateral movement between VL/trunnion, but don't forget that some of these parts have seen considerable mileage.

 

I hope this helps.

 

Martin

[stuart]

Peter is it any cheaper for more than a one off.

Stuart.