1984 3.0 cobra

[Jakem]

Good day....working on friends boat wich had a cracked head...new head installed and tdc set however the rotor is aiming back towards number 4...am I missing something

 

[alldodge]

firing order is 1-3-4-2
It's pointing at 4 means it's 180* out, so move the plug wires in the cap 2 holes or pull dizzy and turn rotor so it points at 1

 

[Jakem]

Got it thanks

 

[Jakem]

Morning...has anyone got the part number for lifters for this engine

 

[Lou C]

I looked the OMC catalog on marineengine.com and oddly they list everything in the valve train except the hydraulic lifters, but Merc used the same engine so I looked it up in the Merc section and here's what they show:

MerCruiser 140 GM 181 I / L4 1982-1986 Crankshaft, Camshaft, Water Pump (140-3.0l / 181 Cid) Parts

MerCruiser 140 gm 181 i/l4 1982-1986 crankshaft, camshaft, water pump (140-3.0l/181 cid) parts. Buy a genuine Mercury Quicksilver or aftermarket part.

www.marineengine.com

Not sure if these are just standard Chevrolet small block flat tappet lifters, or unique to the 4 cyl models. Anyone know?

 

[kenny nunez]

What is wrong with the lifters? If they are cupped on the bottom you will need a new camshaft also.

 

[Jakem]

No there not cupped my concern is if I put it all back together and theres a sticky one I'd have to pull it back apart

 

[alldodge]

No there not cupped my concern is if I put it all back together and theres a sticky one I'd have to pull it back apart

The great part about the 3.0 is it has a inspection cover, so if there is a bad lifter it can be replaced without tearing the motor down

 

[Jakem]

True

 

[Jakem]

What is the best way to set the valve train. What is the sequence of the valves to ajusy

 

[Scott Danforth]

The cobra came out late 1985 for the 1985 model year

If it's a 1984, it's a stringer 400

Lifters same as the 151 4-banger and the 196, 230, 250, and 292 6-bangers

 

[Jakem]

Does that mean the rocker adjustment is different....

 

[Jakem]

Its a 1984

 

[Scott Danforth]

Rocker adjustment is same for all 1990 and below as well as 1991 and above

 

[Jakem]

Ok so what is the process. Its at tdc...

 

[Scott Danforth]

1/2-3/4 turn past zero lash. Start with cylinder 1 at TDC, set lash on 1 and 4

Then rotate motor 180 degrees, do cylinder 3 and 2

Zero lash is the point where the push rod doesn't move up and down, not where you can't spin it

 

[Jakem]

Got it thank you