Steering Control Valve Tech Tip

[jopizz]

I was speaking with Dave Hodges ~ ayrwoof who gave me a tip regarding leaking power steering control valves. It appears that Ford was having the same issue back in the 50's and 60's. According to someone he spoke to who worked at an Edsel/Lincoln-Mercury dealership the fix was to soak the seals in DOT3 brake fluid for 15-20 minutes before installing and install them still wet. After putting the valve together fill with Type F transmission fluid. He says he did this quite a few years ago on his '60 and his valve is still leak free. He also indicated that he got new seals from The O-Ring Store LLC: https://www.theoringstore.com/ The part number for the larger seal is 6226-07-E70. He did not have the part number for the smaller seal but they list many different Ford seal kits so it's best to give them a call.

John

[Tbird1044]

This could be a great fix for a long time ongoing problem. I hope we get some feedback when some of the members try it. It should go in the TRL.
Nyles

[YellowRose]

Steering Control Valve Tech Tip

I have just put this into the TRL in the Power Steering section. You will find it listed in the 2nd link down, •Squarebird Power Steering Rebuild & New Seals Kit. Clicking on that link will take you to the information below that Dave Hodges ~ arywoof provided John ~ jopizz with. I combined the two and modified the title slightly to indicate the seals were available also. Daro at The O-Ring Store (I will add them to the Advertisements Forum) told me that if someone can measure the smaller seal, Inside & Outside Diameter and send them a picture of it with those measurements, they may have that smaller seal also. You can email him at:

daro@theoringstore.com

[simplyconnected]

Wait a minute...
Seals and fluids must be compatible. Normally, seals made for use with DOT-3 will bloat terribly when exposed to petroleum-based products. We also found that silicone-based fluids can bloat certain seals.

'O' rings come in different rubber compounds. Some are neoprene, Viton, Buna-N, etc.

Do NOT buy any 'O'-ring and slap it in your steering system without knowing EXACTLY what it is or another teardown will certainly be in your near future.

It is a mistake to point to the TRL before knowing specifics about compatibility with our steering systems. - Dave

[jopizz]

As I pointed out Dave Hodges had success with certain seals that I referenced in my post. Since his rebuild has lasted multiple years without failure I will assume that the seals he used and the procedure he used was successful. We can only go by our members successes and failures. Any criticism of that is baseless in my opinion.

John

[Tbird1044]

Good point Dave. I looked at theoringstore website and used the part number John listed and it showed it was made from EPDM. Then on the compatibility list, it shows it is recommended for brake fluid and not recommended for auto trans fluid. Hmm? The recommended for trans fluid was viton, Buna-N or kalrez. Of the 3, kalrez was the only one highly recommended for both fluids. Very expensive and may not be available in the sizes needed. I wonder what material Ford used on the original seals?
I think most of the commercial seal sealants in the cans at the auto stores are designed to chemically make the old seals swell. Guess this would be a long term test is someone tries it.
Nyles

[jopizz]

Guess this would be a long term test is someone tries it.
Nyles

The fact that Dave Hodges installed that seal many years ago and it hasn't leaked tells me that neither the brake fluid nor the Type F transmission fluid did it any harm. That's a lot longer than most people are getting out of new seals without soaking them beforehand. I know that from personal experience.

John

[simplyconnected]

John, with all due respect to you and Dave, I must defer to the experts who make 'O'-rings. Parker Hannifin has always been Ford's 'go-to' company. As Nyles pointed out, Parker has a handbook of compatibility because Parker makes 'O'-rings.

They show a listing for Type 'A; Transmission oil but I would call them for other types (like Type 'F'). Here's what they say:

[jopizz]

With all due respect something that has worked in a practical application for multiple years trumps any list you can provide. If I worked on cars solely based on what it says on paper and not by trial and error I wouldn't be much of a mechanic.

John

[YellowRose]

Steering Control Valve Tech Tip

Thanks to John ~ jopizz, we have been doing some research on these seals. John happens to have a few of them, one for the 1958 Spool small end and one for the 1958-1960 Spool large end with an EP45 number on it. That appears to be a Eaton Product Part #, according to Daro at The O-Ring Store. With the measurements and pix that John provided, Daro was able to tell me what their Part # was for those two additional seals. Here is that information.

The O-Ring Store Seal Part #'s

1958-1960 Thunderbird Power Steering Control Valve Seals - Used on 1958-1965 Tbirds (so I read).

1958 Spool small end - 5/8" ID x 7/8" OD - 1/8" C/S - HRU12-0.62-12 Buna-N - 0 In stock but they can get them.

https://www.theoringstore.com/index....=HRU12-0.62-12

1959-1960 Spool small end - 1/2" ID x 7/8" OD x 3/16" C/S - 6226-07-E70. An EPDM seal - 408 In stock

https://www.theoringstore.com/index....rd=6226-07-E70

1958-1960 Spool large end - 11/16" ID x 7/8" OD 3/32" HT - Part # EP45 - HRU09-0.68-09 Buna-N
0 In stock, but they can get them.

https://www.theoringstore.com/index....=HRU09-0.68-09

Daro said that instead of soaking them in brake fluid or Type F, to Use a PTFE Based Lubricant - Part # 21030

Buna-N 6226-07 good for petroleum based uses

https://www.theoringstore.com/index....&keyword=21030

Today, I spoke with Parker regarding the O-Ring Handbook not listing Transmission fluid Type F. What he told me was that Type F was not satisfactory to use either. Here is the information he gave me on page 3-11 of the Handbook.

Parker O-Ring Handbook

http://www.parker.com/literature/O-R...ORD%205700.pdf

For automatic transmission:
Medium: ATF oil (Automatic Transmission Fluid)
Compound: N0674-70, N0552-90, AA150-70,
AE152-70 (Vamac), V1164-75,
V0884-75 (brown)

[Dan Leavens]

John / Ray thanks very much for this, as it will be helpful in outsourcing parts for our members moving forward.

[pbf777]

With all due respect something that has worked in a practical application for multiple years trumps any list you can provide. If I worked on cars solely based on what it says on paper and not by trial and error I wouldn't be much of a mechanic.

John

HEAR,HEAR!

If I may point out, I think the discussion has missed the original intention or perhaps the obvious.

I believe the point of soaking the o-rings prior to installation was because thru experience (see above), one had found that the o-ring material WAS incompatible (one point for DAVE) with the soaking proceedure, and that it was this reaction effect that one sought for the end result of better famililarization between the surfaces leading to a superior sealing value.

And I'm sure the engineers, referring to their material compatibility charts, would be aghast at the idea, but in the end, why was one in the field searching for a solution to a problem the engineers didn't acknowledge or solve first!

Scott.

[jopizz]

The service person Dave Hodges talked to did not indicate if Ford had issued a TSB outlining the soaking of the seals or the mechanics had found this out on their own. Obviously leaking control valves was a problem very early on (and it continues to be) and just replacing the seals was not a permanent fix. Having worked on many different Fords including full size and Mustang the control valves and the seals changed many times until the system was finally dropped. Like many things that Ford engineered in the 50's and 60's you have to ask yourself what were they thinking.

John

[simplyconnected]

...why was one in the field searching for a solution to a problem the engineers didn't acknowledge or solve first?...

The answer is easy (if you think about it). Back then, 'plastics and polymers' were in their infancy. The right compound wasn't invented until later. I won't pretend to be an expert on chemicals or compounds but this answers the question of why so many of our expensive 'steering rebuilds' are not lasting more than a few weeks!

It also addresses the issue of why Stop Switches fail after two years after using DOT-5 (silicone-based fluid). Silicone requires different seal compounds from DOT-3. Compatibility IS the issue.

The automotive industry wasn't alone with this problem. In the 1970s, we (Ford Manufacturing Development) acquired an 'orbital' press, manufactured in Poland. Brand new, it leaked like a sieve because their seals were crap. Our seals were marginally better.

So, mechanics like John were forced to find their own solutions while everyone else simply lived with the leaks.

The Parker handbook is TODAY's compatibility chart which includes compounds I've never heard of. I spoke with our contact at Parker today and he kept emphasizing, 'it depends on the application'. Later, I realized his point:

Not only is the 'O'-ring compound important but so is the transmission oil used, the environment it lives in AND the product's durability index.

Some people are using synthetic and silicone-based oils with the belief that this 'change' is an improvement. Nothing can be farther from the truth.

Some of the part numbers Ray posted in his Parker statement will NOT be suitable in Detroit as they only go down to -5 degrees F. 'O'-ring # AE152-70 (in the correct sized 'O'-ring) is in the temperature range we need for automatic transmission oil. Turns out, Parker makes 20 other choices in that same ethylene acrylate compound that are all compatible. Each compound is designed for specific applications. - Dave

[pbf777]

That really wasn't intended as a question, my punctuation failure.

But, thank you for the additional insight though.

Scott.