4.3 mercruiser vortec issue

greigph

Recruit
Joined
Oct 2, 2024
Messages
3
Afternoon, recently picked up a champion boat with a 4.3 mercruiser MPI engine that was running (on muffs) turned out there was a hole in the head behind the valve which was leaking water in. Got a new head and reinstalling I noticed the valve train had washers between the roller carrier and the head. This was causing the rockers to be loose.
Took the other side off and it also has these washers. I can't see them in any drawing.
 

Attachments

  • VID-20241002-WA0011.mp4
    22 MB · Views: 0

Fun Times

Moderator
Staff member
Joined
May 16, 2009
Messages
9,048
What year is the boat/engine? Serial number handy also is there a difference in the old vs new head casting numbers?

Wondering if this design change maybe doing something.

Description​

Roller Rocker Arm Conversion Kit for 4.3L Marine Engines 2004+. Replaces Mercruiser 883164001, Volvo Penta 3861873. Includes Rocker Bridge. SET OF 6 (ENOUGH FOR ONE HEAD)
Used on 113 casting cylinder heads using a rocker bridge. Typically used on 4.3L engines produced afert 2003. This kit is made for those who want to upgrade to the 113 casting roller rocker cylinder head. Kit includes (6) rocker arms, (1) rocker arm bridge.
Rocker Arm Replaces:
  • Mercruiser #883164, 883164001
  • Volvo Penta #3861873
Rocker Arm Bridge Replaces:
  • Mercruiser #883165
  • Volvo Penta #3861874


 

greigph

Recruit
Joined
Oct 2, 2024
Messages
3
Casting is 113 it's a 2001. It's pickling me as to why they have attempted to raise the entire valve train. Could it be if they have skimmed the head? The builder has just put too big a washer to compensate for the loss of material? Would only expect a couple of thou removed
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,440
Afternoon, recently picked up a champion boat with a 4.3 mercruiser MPI engine that was running (on muffs) turned out there was a hole in the head behind the valve which was leaking water in. Got a new head and reinstalling I noticed the valve train had washers between the roller carrier and the head. This was causing the rockers to be loose.
Took the other side off and it also has these washers. I can't see them in any drawing.
the push rod is moving ?? I understand the valve is closed but the pushrod should not be moving down unless the lifter is collapsed or lifter is not on the cam fully, or is the pushrod not seated against the lifter?

Is this the same for all rockers? No milling the head for warpage would not remove that much material.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,566
I would be pulling both heads and pull the intake to find out what is wrong with the cam or lifter.
 

greigph

Recruit
Joined
Oct 2, 2024
Messages
3
The issue I believe is there is a washer installed between the rocker bridge and the cylinder head. This is moving the rockers further up. Will reassemble it without the washers and fire it up.
 

Scott06

Admiral
Joined
Apr 20, 2014
Messages
6,440
The issue I believe is there is a washer installed between the rocker bridge and the cylinder head. This is moving the rockers further up. Will reassemble it without the washers and fire it up.
After it is assembled Take the plugs turn it by hand to ensure geometry is correct and nothing is hitting
 
Top