Looking for piston ford 302 40 oversize

[Andy]

Hi,
Looking for one Silvolite 1177-040 piston in good condition.
Living in Belgium.

Was installing new rings and felt a binding feeling of one rod in the piston.
It rotates but can feel there is flat spot in the rotation.
Can't be good. :furious:
Was planning to go to the balancing shop this week.


Regards
Andy

 

[Jac Mac]

Does it 'bind' with rod centered between pin boss's, sometimes people slightly damage pin bore of piston if pressing pin to correct location.

if your going to balance shop they will be removing pistons to balance rods/pistons separately anyway, so should be able to check/correct problem at same time,.

Drill pin oilers from oil ring groove to pin bore at same time.

 

[Andy]

Hi Jac,
It binds indeed. Spoke to the balance shop and they are not planning to remove the rods and pistons since it is a shrink fit.
Going to remove the pin and see what is going on. Hope it is only the pin which is bent. First need to find a place to press out the pin before deciding how to continue.

 

[Jac Mac]

Hi Jac,
It binds indeed. Spoke to the balance shop and they are not planning to remove the rods and pistons since it is a shrink fit.
Going to remove the pin and see what is going on. Hope it is only the pin which is bent. First need to find a place to press out the pin before deciding how to continue.

Must be some interesting fudge factors in the balance shops calculations of bob weights if they are not going to remove pistons from rods!!!!
You will probably find the pin has had a partial seizure in the piston concerned, quite common when not drilled for pin oilers and usually occurs shortly after first start.

 

[Andy]

Was able to disassemble the pin and piston. The pin and the piston holes needs a small polish before the pin could rotate smoothly. Guess some minuscule distortion and wear made them bind. All is well and parts are being balanced :thumbsup:

 

[Jac Mac]

Was able to disassemble the pin and piston. The pin and the piston holes needs a small polish before the pin could rotate smoothly. Guess some minuscule distortion and wear made them bind. All is well and parts are being balanced :thumbsup:

'Guessing' should not be part of the equation. Use ~ 2mm drill

 

[Andy]

Unfortunately not have access to the right tooling to make these precise drills.
It is better for the lubrication of the pin, I believe this but not having these holes shouldn't be a big problem since it will not be used for racing. It is a mild setup for the road. Planning to replace it after a few year with a 347 stroker dart based after upgrading the gearbox.

 

[Jac Mac]

These are all the tools reqd to drill the holes, keep the drill bit away from the upper face of the oil ring groove, any precision involved is entirely up to you!

 

[Andy]

Hi Jac,
How are you planning to drill the vertical oil channels ?
With these standard tools, I would try it and have the chance to mess it up is too big. I would give it a chance if I had spare pistons and
if access to a proper fixture to keep the piston aligned and steady and using a proper column drill.
Regards
Andy

 

[Jac Mac]

Info on pic, Ive done them with hand drill or column drill, just whatever is/was available at the time, Helps if you have an old shop rag or towel to set piston in and hold with left hand/drill with right, or vice-versa if your left handed!

 

[Andy]

Hi Jac,
The drawing is clear and in that way it is indeed doable.
At this moment, the pistons and rods are at the balance shop and it will stay for some weeks like this since they found out the rods are out of tolerance regards the roundness. Which means I needed to order a new set and sending it over to them. Small delay which happens in these kind of projects.