May, 2009

Transmission rebuild

After successful engine completion we continue on the next part - C4 transmission. I performed an full overhaul. This consist of all clutches, bands, bushings, rubber o rings and gaskets. I have included new modulator, shift kit and new torque convertor. As usual I have never done this job before so worked according to Haynes manual and internet research. The complete rebuild took me two days. The whole process is described bellow.Now I can only hope that everything will be functional.

New front pump and tail shaft bushings from the rebuild kit. I have replaced only these two. Other bushings seems to be OK. Insertion can be make more easy by heating outer surface.
I need to let machine a bushing insertion tool with correct size. It prevent damage of the bushing during hammering. Front bushing needs to be push in correct angle for proper oiling. This shows required tools.
I next complete front pump assembly. I keep it oiled with ATF type F.but Mercon / Dextron is also possible. New thrust washer kit. I have replaced all in the transmission Most important are the washers in the front called no. 1 and no. 2 du to that affect overall input shaft endplay.
Here is the front pump assembly with thrust washer no. 1 (brown plastic) and no 2. (metal on the top) . Thrust washer no 2 affect overall endplay. I have calculated that I need a washer 2,16 mm thick (original was only 1,25mm] which will give me final endplay 0,023". The specification range is 0.008 - 0.042" so I am in the middle. Next I determined the thickness of washer no. 1. have searched a trick how to do that on Ford transmission forum. Its pretty easy. On the pump insert empty reverse drum and insert new washer no 2. with correct thickness calculated before. For now just keep the original thickness of washer no 1. Thank flip the assembly upside down.
And then measure the gap and this dimension add to the original no 1 thickness. For me I finished with 2,3 mm in comparison to 1,65 mm original. Next I continue with valve body.
I dismantled valve body. clean all passages and valves. For better shifting have installed stiffer springs form small Transgo shift kit. I added a new gasket of course. Next I continued with the transmission build. All parts has been cleaned. I started from back and installed one way clutch. All bands and clutch plates needs to be soaked in ATF fro 15 minutes. Next I put brake drum , low reverse servo piston, and output shaft with new clad seals.
All rubber o rings and gaskets are lube with petroleum jelly for better initial oiling and prevent burning surfaces. The petroleum jelly will evaporate quickly after heating. I completed a subassembly of high reverse drum all with new raybestos clutch plates Next I have added new low reverse and brake bands with its control servo pistons which are visible on the sides of the case. Insertion of the pump. At this time I made it wrong because I did not notice that 4 clad seals on the pump shaft are with different thickness. It was not visible for the first view and Haynes manual di not notice this. I cannot get the pump in when the clad seals were wrongly positioned and I broke one clad ring as well. After correction it going easily. No adhesive is put on the front pump to case gasket.
Front pump is in place including bellhousing. I inserted the valve body and checked the piston work with compressed air just before.
...and final job is done. Installation of the oil pan and on the cork gasket. It is not recommended to use any gasket sealer but I used a very thin layer of silicone sealer just to ensure proper sealing. It should be very thin than no excessive sealer can be loose and plug oil passage in the tranny.I also adjusted the band nuts for proper torque settings.

Interior panel repair

This starts like a nightmare how to do that. I relay doubt about the result. Formally the interior was in vermillion red option. I spend a lot of hours with thinking and trying of correct processes. Finally I used following method.
1. Forget for spray can paints. The spraying is not consistent. I have ordered cans with vermillion color form Mustang unlimited. Actually they send me more orange color which did not match with the seat upholstery at all..
2. The correct surface preparation is the key. I have used following process on the old scratched panels.

  • I wipe the plastic with solvent which do not harm plastic.
  • Apply some putty in the big holes, than sanding of scratches.
  • Water sanding with 400 grit - this is absolutely important.
  • Spray plastic adhesion promoter.
  • Spray with epoxy primer for best adhesion of next layers.
  • Water sanding with 800 grit.
  • Spray the correct color.
  • Apply 2K 75 % matte clear.

    • On the texture plastic I add a powder texture additive to the clear or paint. Orange peel is rather beneficial on tellurized plastics.

    Example of damaged surface scratched panel. Small scratches can disappear after heating with the gun . The deeper one needs to be sanded off but this will damage the texture. Sanding the scratches with ++120-200 grit and final preparing with watter sanding with 400 grit.
    Cleaning with soapy watter. and drying in the sun.
    Here you can see wrong results due to bad preparation of surface ( I did not sand the plastic with 400 grit). I sprayed a plastic adhesion promoter and next gray epoxy primer.
    I let the pain shop to ix me the desired color according to upholstery sample. I wet sanded the primer with 800 grit. clean it with water and solvent and than sprayed two layers of color base coat and than two layers of clear.
    Rear panel are two color black and red so I need to mask it. And next parts.
    Center console and rear panels. Seat covers.
    Back panels. Another detail. The holes will be covered with speakers.
    Powder texture which imitate the texture in plastic. It can be used in basis color or into the clear coat. Center console...