TR2/3/3A Topping off rear shocks on TR3

[Member 10617]

How do you check and top off the fluid in the rear shocks of a TR3? The new shocks available from Moss for the TR3 don't have the filler plug on the top of the unit that the TR2 appears to have had, and that the TR4A solid axle suspension has.

 

[Geo Hahn]

I guess I've never seen what they sell as replacements. The fill plug on the originals (mine anyway) is on the side though up near the top.

 

[TR3driver]

Ditto. If they don't have that plug, I suspect you'll have to remove the shock from the car and remove the top cover. I would add the plug at the same time (being careful not to let any swarf loose inside the unit).

BTW, IIRC the original plug is a Whitworth size.

 

[sp53]

I would not worry about it. The shock sounds like a sealed unit. If there is fluid coming out, get a new one. I would not break the factory seal only out of curiosity.

 

[Member 10617]

There's no fluid coming out, so the units seem to be OK.

Manual instructions say that the units should be checked and topped-0ff every 12,000 miles, so that is why I have looked into it.

The plug appears to be on the inside, near the top (and not on the top), as George has pointed out.

George: Have you ever topped-off your units? If so, what procedure did you use (jack up the car, etc., etc?) Does part of the procedure include pumping the unit for possible air in the fluid.

 

[mgbmedic]

My car is a 58 and it is filled from inside the car. There are plugs under the carpet for access. I'm not sure on post 60,000 cars with the flat rear shelf.

 

[Geo Hahn]

When I pull the wheel off I'm looking right at the plug -- so perhaps mine is different form yours. I just use a little squeeze bottle with a pointy tip that I keep filled with shock oil. All I'm doing is adding a bit until it runs out to be sure it's topped up so I do no pumping.

I just do it whenever I'm doing the usual rear maintenance (oiling the springs, adjusting the handbrake, lubing the bearings, checking the shoes. etc).

 

[TR3driver]

My car is a 58 and it is filled from inside the car. There are plugs under the carpet for access.

So, how does that work? Your shocks have the plug in the top and the hole in the body is in the slanted part of the "shelf"?

I've owned several pre-60K TR3/As, and they have all had the plug in the side of the shock, accessed behind the rear wheel.

 

[Member 10617]

George: Just what I needed to know. I'll use a squeeze bottle and fill it just as I fill my transmission: fill until it flows out (finds its proper level naturally) and then replace the plug.

My one concern was whether, when opening the plug on the side, if the unit was not positioned properly, the fluid might be forced out in some way. I have read in another forum posting that when some guy opened his plug, the fluid "shot out." Someone who answered him suggested that someone had overfilled the shock and pressure had built up.... I assume, from what you have written, that I don't have be concerned about this or position the unit or the lever in any special way, other than to jack up the car and remove the wheel.

With the VA DOT hard pressed for funds, our roads are becoming rougher to ride. Thus, need for fully functioning shocks... (ha, ha)

Randall: Many thanks for the photo! These ALWAYS help.

BTW. I see now in the Moss catalog illustration of the rear shock absorber that the plug is shown, but not labeled. Every other component is labeled, but not the plug. Go figure?

 

[TR3driver]

Randall: Many thanks for the photo! These ALWAYS help.

That is a blow-up from Practical Hints 6th ed. Good reference for any TR3 owner (although the 6th ed was for post-60K cars). Reprints are available from TRF, I believe.

 

[Member 10617]

Hi, Randall,

Thanks. I have the manual (an original copy, in fact), but that's the one manual I didn't consult when trying to figure out where the plug is located. Should have known...

 

[Geo Hahn]

...With the VA DOT hard pressed for funds, our roads are becoming rougher to ride. Thus, need for fully functioning shocks...

Though these cars ride surprisingly well with no shocks (or I should say a shock that has become unbolted). Makes a heck of a noise though.

 

[PSUTR3B]

I have not checked fluid level in the shocks. What fluid is used for topping off?

Gary

 

[Geo Hahn]

There is a purpose-made oil sold by the usual vendors though I use fork oil sold by local motorcycle shops. That oil comes in specific weights so you may want some advice on what weight to use.