somanytractors
Silver Member
I' going .020 over on this motor. I got a kit with pistons for it on ebay and the pistons look different.
I know this doesn't mean they're not the right pistons especialy with it going 20 over. but I want to make sure before having it bored 20 over and putting it together just to find that it's not right.
What concerns me is 2 differences. the cup in the top of the new pistons is about 1/4" wider which will lower compression. But, it might be a little shallower and it is .020 over so it might be right with the bigger pistons.
The second thing is the distance from the top of the wrist pin hole to the top of the piston is roughly .040 longer {old is 1.91 new is 1.95} so it's going to come closer to the head. However the ones that are in it dont quite make the top of the block, and there's the thickness of the head gasket so I don't really thiunk .040 will be a problem but I'm really not sure, especially considering ford at one point made a change to the pistons in some of the gas 4000s and this kit supposedly fits gas and diesel. The seller confirmed that it's right for my block but I don't know if I just want to take their word on this as they have nothing to loose if I get it all done and it's wrong.
It's a diesel.
The casting number on my block is C7NN 6015 AK The numbers on the tractor are useless as someone swapped tractors in the 4500 frame
I found 2 numbers on the pistons that are in it, C5NN 6HOH and M396C with BL4 under it.
The new ones are numbered new holland 87579814
Can anyone verify that these numbers are correct, or if the pistons look right?
Any help would be greatly appreciated. I'm stuck here.
I've attached a few pics
Thanks
John
I know this doesn't mean they're not the right pistons especialy with it going 20 over. but I want to make sure before having it bored 20 over and putting it together just to find that it's not right.
What concerns me is 2 differences. the cup in the top of the new pistons is about 1/4" wider which will lower compression. But, it might be a little shallower and it is .020 over so it might be right with the bigger pistons.
The second thing is the distance from the top of the wrist pin hole to the top of the piston is roughly .040 longer {old is 1.91 new is 1.95} so it's going to come closer to the head. However the ones that are in it dont quite make the top of the block, and there's the thickness of the head gasket so I don't really thiunk .040 will be a problem but I'm really not sure, especially considering ford at one point made a change to the pistons in some of the gas 4000s and this kit supposedly fits gas and diesel. The seller confirmed that it's right for my block but I don't know if I just want to take their word on this as they have nothing to loose if I get it all done and it's wrong.
It's a diesel.
The casting number on my block is C7NN 6015 AK The numbers on the tractor are useless as someone swapped tractors in the 4500 frame
I found 2 numbers on the pistons that are in it, C5NN 6HOH and M396C with BL4 under it.
The new ones are numbered new holland 87579814
Can anyone verify that these numbers are correct, or if the pistons look right?
Any help would be greatly appreciated. I'm stuck here.
I've attached a few pics
Thanks
John
