So I recently bought an '80 model F100 custom with a 300-6 and granny 4 speed from a guy up the road and the rocker arms are ticking a bit. After researching online I'm having a bit of trouble finding the right ones. I know they have 1.6 ratio stock but I was looking into going to 1.7s. Would I have any trouble with that? Also I'm seeing numerous different ways on how to actually change the rockers. Never worked on hydraulic rockers before so what is the correct way for this motor? Thanks.

 

Welcome to FTE.


Have you given a look see in this area? https://www.ford-trucks.com/forums/forum52/
I have not looked into this but have seen a few post in that area of guys doing this.
I want to say they use Chevy rockers on our 300but again I have not looked into this just what I have seen posted when reading quickly.


Now even with either new 1.6 or 1.7 rockers the "ticking" may not go away.
I say just because if the lifters have any crud to keep them from pumping up all the way or the cam is going flat and the lifters are already pumped up all the way the noise will still be there.


How many miles on the motor?
What is the oil PSI like using a real gauge not the stock dash gauge?
Has the oil been changed when it should had or does it have mud in there?


**this may be a good thing or bad thing**
You can try something like Sea Foam in the oil before changing oil & filter to clean the inside of the motor and may be any crud in the lifters?
I say bad because cleaning may cause leaks and also lower the oil PSI as it now opens up passages and internal leaks.


I would say if the insides don't look to dirty I would try Sea Foam and oil change to see what that does before rockers change. If you don't get them quite rocker will not either.
Dave ----

 

When you start messing around with the valve train, you need to keep a close watch on the geometry of the system. Different rocker ratios means different distances from the ends of the rockers to the fulcrum point that it pivots on. You need to make sure there are no radical angles, and when the extra lift is introduced, that the spring coils do not compress till they hit one another.

I looked up the 300 six, it seems unlike the v8's, they used studs and nuts. While this system stock is still not adjustable(the instructions tell you to lock the nut down to a certain torque) you probably could get a locking nut system of some sort and make it somewhat adjustable. You will probably need to convert it to have some adjustment if you are going to play with the system at all.

 

Dave, you are right on needing to "check things" but going from 1.6 to 1.7 is not a lot and others have done it I just have not looked deeply into it to know the in's-n-out's of this swap.

I don't know of any stamped steel rockers that are adjustable most are roller.
I take that back GM had adjustable on their v8's and maybe the six?
That valve train was made to be adjustable and used lock nuts.

Rollers also use a taller nut with a set screw in the top center, I forget the name of them. When the rocker is adjusted right you tighten the set screw to hold the nut.

I still say changing rockers is not going make the noise go away it is only going to open the valve a little more.
Lifter is not pumping up, low oil PSI or it is at the end of it's range, flat cam or a little of both.
Dave ----

 

The earlier Ford v8's can be converted using the stock rockers. Its just a extra tall nut with a Allen screw in the top for a lock.

 

Fuzz, thanks for the help. The odometer reads 58K but I'm sure it's been rolled back. I'll drain the oil and see how bad it is, but to the best of my knowledge it has been taken decent care of. Also, I'll have to get an oil pressure gauge and check into that as well. I'm currently trying to get my 06 mustang put back together, thermostat blew out and I snapped a bolt trying to replace it. Should have it fixed this evening, then I'll start tearing into the truck and post my findings. Thanks again guys.

 

C5AZ-6564-A .. Rocker Arm / Obsolete

1965/74 240/300 I-6; 1975/84 300 I-6