Volvo Penta MD7A Motor

[Alex James]

I had to replace the injector tubes and need to know the headbolt torques and the valve settings, if anyone has a manual I would appreciate the information- owner of a 78 CD28.

[Stan W.]

According to the manual that came with my boat the data is:

Head bolts: 51 lb/ft

The manual suggests tightening in 3 stages. Stage 1 - 7 lb/ft; Stage 2 - 29 lb/ft; Stage 3 - 50 lb/ft (note 1 lb/ft descrepancy).

There is a specific tightening sequence that is easier to diagram than it is to describe, but I'll try. Orientation is standing in front of motor facing aft.

1. center right
2. center left
3. right edge rear
4. right edge forward
5. left edge center
6. center rear
7. center front
8. left rear corner
9. left front corner

Valves: 0.012" HOT for both intake and exhaust.



smwheatley@capecod.net

[Stan W.]

Whoops, I gave you the sequence for the MD 6A which is covered in the same manual. For the MD 7A sequence is:

1. center
2. left edge center
3. right edge rear
4. right edge forward
5. center rear
6. center front
7. left rear corner
8. left front corner

Again, orientation is from front of motor facing aft. The rest of the data is the same for both.



smwheatley@capecod.net