[Augusto]

I'm having low compression and vaccum reading issues due to the valve train not seating well,

I've made a compression test and it indicates valves not sealing well, I just lapped them so the seats are not the problem.

I belive they are kept open by the lifters.

Is it possible to convert them to adjustable, like the chevy engines?

Can I use chevy rocker arms in them? I6 or V8 pieces?

What is the rocker arm ratio of the I6 Ford engine?

thanks a lot.

 

[[email protected]]

You did not state the year of your engine. Early 300 six engines use guided cast rockers that can be lashed. Similar to the 289-302 early rockers.

 

[BogiesAnnex1]

I'm having low compression and vaccum reading issues due to the valve train not seating well,

I've made a compression test and it indicates valves not sealing well, I just lapped them so the seats are not the problem.

I belive they are kept open by the lifters.

Is it possible to convert them to adjustable, like the chevy engines?

Can I use chevy rocker arms in them? I6 or V8 pieces?

What is the rocker arm ratio of the I6 Ford engine?

thanks a lot.

I'm not to sure that lapping if that's all you did will be adaquate, especially if this is a heavy duty or an emissions head with hardended seats.

So that leads me to the question as to whether you used a seat cutter/ grinder before lapping? Lapping alone as a seat restoration process makes the seats too wide and the valve ends up not settling well on the seat. Also, did you restore/replace the guides. When these get loose the valve rather orbits the seat having a hard time setting itself down.

Bogie

 

[Augusto]

You did not state the year of your engine. Early 300 six engines use guided cast rockers that can be lashed. Similar to the 289-302 early rockers.

it's a 1987 engine, came out of a E350 Econoline, it's installed now in my son's Granada.

I don't know about the early 289-302 rockers, this is my first time I deal with Ford engines.

the rockers are cast not stamped like the chevy units.

you mean there's a way to adjust them valves? shims or something?

the truth is I would love having a chevy-like system, adjustable by turning them loose 'til they make noise then tigthen down 1/2 turn, you know what I mean right?

 

[Augusto]

I'm not to sure that lapping if that's all you did will be adaquate, especially if this is a heavy duty or an emissions head with hardended seats.

So that leads me to the question as to whether you used a seat cutter/ grinder before lapping? Lapping alone as a seat restoration process makes the seats too wide and the valve ends up not settling well on the seat. Also, did you restore/replace the guides. When these get loose the valve rather orbits the seat having a hard time setting itself down.

Bogie

I just lapped them to clean up the grime, the engine sat down for several years, the seats and valves are ok, not worn, so are the guides, they didn't need a restoration, the engine has low millage, they are not too wide now, I lapped them not to correct any problem, just a clean up job.

 

[[email protected]]

Early ( late sixty-early seventy) 300 use a crimped nut, similar to chevy. That can be used with the guided cast rockers. These adjust just like a chevy.

 

[Augusto]

the nut just bottoms out and can't be adjusted any further, do I need longer push rods or do I have to machine down the head bosses or the rockers?