Honda bf20d torque specs

[Kevin honda]

Hi I'm new to this forum. I am currently working on a Honda 2004 bf20d
A valve spring broken and caused severe damage to the valve seat area and the head must be replaced
I have one coming from a used bf15d. As far as I can tell all the part numbers are the same alas the bf20
I need the torque specs for the head bolts and torque pattern
I also need to know if when torquing these head bolts do they get the extra 90 degree tightening
Also do these head bolts need to be lightly oiled before installation

I also removed the crankcase cover to ensure there was no damage torque specs for this would also be appropriated

Lastly the flywheel torque specs

Normally I would purchase the service manual. But it is a students project and they are already financially tapped out

Thanks any help would be appreciated

 

[Sea Rider]

Welcome to Iboats,

Don't have specs for Honda OB's, can answer some of the questions.

- Clean all powerhead threads and bolt threads,

If say it's a 10 bolt cylinder head pattern is like this :

9-10
5-6
1-2
4-3
8-7

- Start at 1 then 2 and contiunue 3-4 / 5-6 / 7-8 / 9-10 in CW pattern.

-Torque in small increments each bolt at a time. Say if bolts needs to de torqued to 30 NM, first torque is 10 NM, second 20 NM, third fully to 30 NM. Don't over torque beyond max.

-Lightly coat with marine grease each bolt body & threads before torquing.

Torque specs is a must have, if not can pull threads out which is no bueno!!

Happy Boating