L83 DOD manifold oil supply plug

[87chevy.com]

After experiencing what sounds like a collapsed DOD lifter, pulled the head and inspected #6 lifters they are locked in the right position compared to #4... not 100% sure as the heads still not back on it but after looking for solutions to prevent oil to enter the VLOM or LOMA found only one guy that sells a sleeve that looks like he tool a cylinder head down and ground it against the concrete..

Measured the hole, searched and found a dowel pin that is the right size.

Spare VLOM with the solenoids removed..



Sleeve / dowel pin



Installed with green locktite as a lube



Reinstalled the hex cap plug, turned the manifold upside down and leak tested it.. it has a tiny bit of seeping air pressure, 125psi... prob not enough that it could reach the lifter to collapse it if a solenoid stuck open (since there a bleed off port/ screen).

In the end, a complete DOD delete is the best, but this 3$ mod feels like it's worth it!

[jjzepplin]

Interesting.

[87chevy.com]

Put about 100 miles on since the replacement lifters and plug installation and good to go. So i would say i had either failing afm lifters on #6 or a leaking manifold... the engine has kess than 12k on it... but last 2-3k have been seen WOT atleast once per drive cycle
Clint

[jjzepplin]

What year is your engine? How many miles? Can I get to this without removing the intake?

[87chevy.com]

Originally Posted by jjzepplin

What year is your engine? How many miles? Can I get to this without removing the intake?

2015 from a Tahoe, think it was around 9k miles when I got it. Intake has to come off to access it.
clint

[jjzepplin]

Mine is a 2014 and under hard acceleration it will back fire a little. 79000 miles and I am a little worried.

[jjzepplin]

Do you have information on the plug you used?

[87chevy.com]

BMW part number 11121726243 13.5mm dowel pin

It does need to be tweaked, I used a 1/4 deep socket that's slightly larger than the ID of the dowel pin to expand it a tad, forgot what size craftsman deep socket i used, but it was just just a little bigger than the ID and put tension when installing it.

You need to measure how deep to drive the dowel pin in... i think its around .9 or so from the top surface to cover the oil supply hole. Simple harbor freight dial calipers is what I used and use for all my projects. if you drive it in too far, the oil supply hole will not be covered up and not sure if you can just drive another dowel pin in and hope for the best.. but measure and you'll be ok

I think the oil supply hole is only .25" and the insert is like .5" so