Mazda 5. Manual - part 82

09–80E–4

BODY STRUCTURE [PLASTIC BODY PARTS]

serious to be restored by painting only.

1. Cut the rough edges around the damage with a knife to make it smooth. Sand the area with a sander to make 

an angle of about 45

°.

2. Weld the damaged area.

• For repair of a cracked area, melt the crack together with a heat gun and a melting attachment.

Hole

A

A

A-A Section

Crack

B

B

C

C

Flaw

D

D

B-B,

C-C

Section

D-D Section

Top coat layer

Primer layer

Primer surface layer

Polypropylene layer

4

4

3

3

1

1

2

2

ZUA9818B001

A-A, B-B, C-C Section

Cut with knife

Polypropylene surface

D-D Section

Cut with knife

Sand

Sand

Angle necessary for deposit of polypropylene welding rog 

45

°

ZUA9818B010

BODY STRUCTURE [PLASTIC BODY PARTS]

09–80E–5

09

• For repair of a hole, degrease the area on both sides of the bumper and apply aluminium tape on the 

reverse side of the damage area.

3. Melt the polypropylene welding rod with a heat gun and deposit it the cracked area.

Note

• Heat the shaded area to melt it.

• Take care not to overly melt welding rod. If the part is welded with the welding rod melted like jelly, the 

welding strength will be reduced.

• Hold the heat gun 10—20 mm {0.39—0.79 in} from the part being welded.

• Do not move the welding rod until the welded parts cool.

Polypropylene surface

Heat gun

Attachment  for
melting

painted surface

Melt together

B-B,C-C  Section

Section after melting

ZUA9818B003

A-A Section

Degrease

Aluminium tape

ZUA9818B005

Polypropylene welding rod

Polypropylene welding rod

Melt this area

Melted area

B-B,C-C,D-D Section

ZUA9818B004

Polypropylene welding rod

Polypropylene welding 

Paint

Top view

A-A Section

Surface

Aluminium tape

ZUA9818B006

09–80E–6

BODY STRUCTURE [PLASTIC BODY PARTS]

4. Sand the surface of the polypropylene gradually as it is easily melted by the abrasion heat. Sand the area to 

which repair agent will be applied.

5. Uniformly apply polypropylene primer with a brush to an area larger than the repaired area. Allow to dry about 

10 minutes at 20 

°C {68 °F}.

6. Mix the main agent and the stiffening agent in a ratio of one to one. Apply the mixed repair agent to the 

damaged area.

Note

• When mixing the main and stiffening agents, take care not to allow bubbles to form.

• The repair agent hardens quickly (about 5 minutes); proceed with the work immediately after mixing the 

agents.

• Allow about 30 minutes to dry (20 °C {68 °F}) before sanding.

The repair agent is a two part epoxy adhesive.
When the repair agent hardens, it will provide a good finish with the same flexibility as the polypropylens.
The repair agent for a urethane bumper is also a two part adhesive compound. However, this is different from 
that for a polypropylene bumper. If the incorrect repair agent is used, the repair will be faulty.

7. Sand the area with #180—240 sandpaper.

Note

• If excessive force is applied to the area when sanding, the surface will be damaged.

• If fuzz remains around the repaired area, melt it with a heat gun.

Sand gradually

Sand repair area

Paint

YMU980PCX

Larger than repaired area

Polypropylene primer

YMU980PCY

Repair agent

Do not mix air

Weld

Polypropylene surface

YMU980PCZ

BODY STRUCTURE [PLASTIC BODY PARTS]

09–80E–7

09

8. Degrease the painted surface.
9. Mix the primer and the hardener at a ratio of one to one. Apply the primer to the repaired area and the surface 

of the bumper with a brush or spray.

Use the primer within 16 hours after it is mixed.

Note

• Polypropylene primer will dissolve even after drying if it is wiped with solvent. Use only water to clean 

around the primer.

10. Allow the part to dry.
11. Add the softener to the urethane primer surfacer and spray it on the repaired area.

a. Mixing method

Urethane primer surfacer + Softener ..... Mixture A
Mixture A + hardener ..... Mixture B
Dilute mixture B with thinner to spray on bumper

b. Viscosity

YMU980PD0

1

1

polypropylene primer

Primer hardener

YMU980PD1