Valve Adjustment on a 2.5 L

[starcrafter65]

I have a 2.5 4 in line that I just purchased - it is from a 1968 Starcraft.

The previous owner had done a head and valve job and run out of steam. The motor is ready to be run again - and I just want a reassurance about valve adjustment. The "book" says go to TDC on #1 piston and tighten a sequence of 4 of the 8 valves. Says to tighten to intial compression on the lifter and go 3/4 more turn. Then go to TDC on #4 piston and do the rest of the valves.

The previous owner said more like - get it running and tighten as it is running to eliminate the "clattering".

I did what the book says - but it just seems like you are tightening the heck of them.

Anyone with real know-how on this procedure - I would like to get this close before I try to start them.

Thanks

Clark

Resto Thread in the Starcraft forum

 

[starcrafter65]

Re: Valve Adjustment on a 2.5 L

Here is what I clipped from a similar post

"The biggest problem is, when a newbe goes for zero lash where the pushrod doesn't turne, he should be using 2 fingers. Not vise grips to feel when it stops. When it stops, don't even think about trying it again, and newbe's do, so the adjust and adjust till they run out of room.
Turn it down till the push rod stops, do the additional 3/4 or full turn per the manual, and you are set to go.

Oh, yeah, you need to pump up new or rebuilt lifters before you try to adjust."

So - "lash" means loose - till it just starts to tighten...correct?

And can someone clarify the part about "pump up new or rebuilt lifters before you try to adjust"?

Thanks again

Clark

 

[Bifflefan]

Re: Valve Adjustment on a 2.5 L

I
The "book" says go to TDC on #1 piston and tighten a sequence of 4 of the 8 valves. Says to tighten to intial compression on the lifter and go 3/4 more turn. Then go to TDC on #4 piston and do the rest of the valves.

This the correct way to do them.
As to the PO's way, i have done them on motors that have been running previously but on a new one or one that has the head off, do it by the book.

As a side note I only go 1/2 turn extra. This is just in case you over rev the motor and float a valve it wont hang open as far and the chance of hitting a piston is a little less.

 

[JustJason]

Re: Valve Adjustment on a 2.5 L

As a side note I only go 1/2 turn extra. This is just in case you over rev the motor and float a valve it wont hang open as far and the chance of hitting a piston is a little less.

Its a non interference engine, it doesn't matter if the valves are all the way down and the piston is all the way up.

Do a compression test. Adjust the valves. Redo a compression test, if your compression went down your to tight on the valves.

Loosen up a rocker when the piston is at tdc on the compression stoke. SLOWLY tighten the rocker while rolling the pushrod at the same time. When you feel the a light to meduim drag on the pushrod using just 2 fingers and not a pair of vicegrips that is 0 lash. Its 3/4 of a turn after that.

 

[jack gardner]

Re: Valve Adjustment on a 2.5 L

ok pump up lifter soak in oil one way second is to prime engine with oil pump thru dist oil drive . third way take each lifter in oil filled container and push plunger up and down till bubbles stop. ok lifter is full now u can install adjust down till u can turn pushrod with two fingers move on to next same thing on all now turn engine by hand till some r loose adj accordingly till u hav all the same now go 3/4 turn in and u should b good good luck and happy boating .u can follow the manual and go by the sequence but it all works but just the simple way is easy 4 a layman

 

[wvmedic]

Re: Valve Adjustment on a 2.5 L

starcrafter65, do as justjason advised.

Loosen up a rocker when the piston is at tdc on the compression stoke. SLOWLY tighten the rocker while rolling the pushrod at the same time. When you feel the a light to meduim drag on the pushrod using just 2 fingers and not a pair of vicegrips that is 0 lash. Its 3/4 of a turn after that.

Do the above following the sequence of the manual.

Jeff.

 

[Howard Sterndrive]

Re: Valve Adjustment on a 2.5 L

I always use a compression gauge to set valves on i/o's.
Too risky if you get it wrong.

 

[Bt Doctur]

Re: Valve Adjustment on a 2.5 L

After making sure the lifters are pumped up, (oil pump priming tool) you can do each cylinder .turn engine untill intake valve fully opens and then fully closes. adjust pushrods ,go to the next cyl.etc.