Shifter Shaft Seal revisited

Thank to all whom wrote tec briefs on the shaft seal replacement, I’ve plagiarized some of your work, and added more which I trust will help others in the future. Below is the 21 step process.

Shifter Shaft Seal replacement
328 / Mondial

1.) Drain Engine oil (12mm Allen). (It would be best to drain the oil out of both sumps at least a day before starting, longer will lessen oil from dripping when you’re working).

2.) Drain Trans oil (10mm Allen).

3.) Prior to removing oil temp sending unit (22 mm or 7/8” open wrench); use a spray cleaner in the area.

4.) Remove 10mm nuts and spring washers from both pans. (Keep in mind the trans has 3 balls, springs and one spacer (Left hand front), they will fall out when the pan is removed don’t drop them in the oil). Location is as follows;

a.)The front hole will have a ball, spring, a spring cup, and a spacer which rests against the pan.

b.) The middle hole should have a ball and spring.

c.) The rear hole should have a ball and spring.

5.) Loosen the selector arm in trans from the rod end using a 13mm shallow socket and 3/8” ratchet (a deep socket helps to unscrew bolt by hand, the bolt needs to be removed completely)

6.) Remove the shifter shaft rod bolt from the two linkages, between gas tank and engine (two 13 mm open boxed wrenches).

7.) Pull the dust cover boot off the trans leaving it on the shaft.

8.) You should be able to remove the shifter shaft by putting the gear selector in 3rd gear, and pushing the linkage under the car up and over providing barely enough room for the shifter shaft to be slid out, once it’s out, it will need to be angled to be completely removed from the car.

9.) Pull the seals, using a pick, (do not remove the washers holding the seals in).

10.) Install new seals; angling the cups towards each other (sealing in the engine oil) (Seals are 20-28-5.5 mm Viton cup seals). This assumes you have the revision seal from the pre 80 81ish quad seals / O-Rings.

11.) Now’s the time to replace the shaft bushing. Replacing it with a polyurethane Stainless bushing will provide a lifetime fix (no oil degradation like with the rubber OEM type).

11.) Using 1200 grit and a light oil, lightly burnish the shaft, clean and install new dust boot lightly grease around boot seal on the rod.

12.) Swab your choice of grease on the new seals, Slide the shaft back into hole. (Sliding the shaft back in is harder, the end of the shaft doesn’t want to line up with the seal & hole separating the trans from the crankcase, carefully using a light rubber hammer hit will help).

13.) Install the selector arm and pinch bolt on the rod end (13 mm socket) (aligning the rod groove with the bolt, center axially and horizontally then tighten the bolt loosely).

14.) Slide the shaft boot over the snap ring on the trans.

15.) Now is the time to check and see if the gear selector is “centered in the gate (forward / back, there should be equal distances between 2nd and 3rd “end of gate gaps). If it’s not, now is the time to make the adjustment. Remove the center belly pan (10 mm bolts); you will find a turnbuckle for the length adjustment (two lock nuts and one adjustment nut (Two 19 mm open end wrenches). Keep in mind the rear linkage rotation WILL change the rotation of the shifter selector arm in the trans, (To adjust ALWAYS put the gear selector in 2nd gear, make sure the selector arm in trans is “centered on the second shift finger (my experience is it needs to be a tad .03” higher on the middle finger, verses perfectly centered).

16.) Once the gate shifter is adjusted forward / back, they should be at equal distances, install a thick piece of cardboard around the shaft (.050” thick) and shift into 2nd gear (the cardboard will space the shaft in the center of the gate allowing you to readjust the selector arm and pinch bolt correctly.

17.) Loosen the selector arm in the trans and re-center it on the shift fingers, retighten the bolt (12 mm socket). Keep in mind the arm will need to be .03” higher on the center finger.

18.) Install the oil temp sender (22mm open end wrench or 7/8).

19.) Install oil pan (10 mm) and plug (12 mm Allen). (The gaskets, both engine and sump, go on only one way, trial fit to insure all holes line up before applying your favorite adhesive. Bonding the gasket to the cover before installation is easiest.

20.) Install the trans pan (10 mm) and plug (10 mm Allen), put your favorite grease on the ball, spring and spring cup to keep them in the trans while you install the pan.

21.) Fill engine and trans with oil, (check for leaks periodically during the fill process).


Good luck!

 

My understanding is the “O-Ring was the first iteration, then a quad seal was used and finally a regular Viton / Buna cup seal was the final solution somewhere in 1980 81 era. I believe the cup seal will fit on all previous models.

I don’t believe the cup seal on the transmission side is the best solution (you have oil going both ways) what do you do? Logically, you change engine oil more often than trans fluid, therefore if trans fluid gets in the oil, it won’t be there as long. Also combustion gases create more pressure in the crank case (unless you consider PCV) than the transfer unless the vent plug in the transfer case is blocked. So I guess it makes as much sense as it’s going to, I believe the engineers ran out of solutions without retooling the block.

I’m not taking it back apart for a photo shoot, sorry!

JH

 

Do you have the specifications on the quad ring (ID, OD, and Width)?

 

McMaster-Carr# 6540K151 seal is a 211, which has a physical size of, 1/8” .139” x 13/16 (.8125”) x 1-1/6 (1.0625”)”. The shifter seal dimensions are 20-28-5.5 mm. If you do the math, you will end up with a difference of;

Quad seal OEM Metric seal Difference
1/8” (.139”) 5.5mm (.2165) .0775”
13/16 (.8125”) 20mm (.787”) .0255”
1-1/16” (1.0625”) 28mm (1.1023”) .0398”

Not sure if it makes a difference in seal performance, but seems like a significant difference to me, especially the thickness 1/8” vs 5.5mm a difference of .0775”.

JH