padam
Well-Known Member
RC had a worn part checked, and it was still hard.
RC had a worn part checked, and it was still hard.
He had the surface checked. That will not tell you if it is through hardened. Unfortunately to check for through hardening you must destroy the part by sectioning the area you want to investigate. If the surface shows Rc60 and the core is Rb85 then it is case hardened low carbon steel. If it reads high on the Rc scale all the way through, then it is through hardened medium or high carbon steel.
The reason I was saying to check a worn part was that once you check it....there is no going back. You can also check a new one, but it will be a sacrificial lamb. You would have to buy a new one if the original checks good.
RC had a worn part checked, and it was still hard.
I'm thinking it was probably his head.......the one on his shoulders?RC had a worn part checked, and it was still hard.
That's like breaking a shatter resistant window to see if it really is shatter resistant.
If you say so.Padang
If you look at post 5 the fifth picture down it looks to be case hardened. It appears to have a axial crack that is only about .015” deep from the surface. The pushrod wore significantly in length once the case was compromised.
This thread may be of interest. It is concerning the massive springs that are in many mechanical fuel pumps made today and the overly high force it takes to work them. Also the crappy assembly of the Carter pump's diaphram assembly. It may not be the problem but it could be part of it.
Mechanical Fuel Pump 101
https://www.forbbodiesonly.com/moparforum/threads/mechanical-fuel-pump-101.194336/#post-911570724
The business mentioned in that thread is not far from me.
It’s a different application. Seems lifter-ish but doesn’t have the crown or spin of lifters, nor the surface area. When designed it was made for the mild factory fuel pumps you could pump with the arm in the palm of your hand. .. and that was with the good factory rods.
The higher volume pumps would push a hole through your hand! A whole different deal. Still ok with the good, thru-hardened rod but use the crappy rods and the show is over. More reason people seek out actual factory parts, the engineering is almost always better, when you can spread that research over hundreds of thousands of cars you can donit better.
I have never been inclined enough to measure fuel pump lobe taper.. but they are designed to spin by simply looking at enough of them. I would say it's when they stop spinning that they will start to get trashed.It’s a different application. Seems lifter-ish but doesn’t have the crown or spin of lifters, nor the surface area. When designed it was made for the mild factory fuel pumps you could pump with the arm in the palm of your hand. .. and that was with the good factory rods.
The higher volume pumps would push a hole through your hand! A whole different deal. Still ok with the good, thru-hardened rod but use the crappy rods and the show is over. More reason people seek out actual factory parts, the engineering is almost always better, when you can spread that research over hundreds of thousands of cars you can donit better.
Didn't know that, but it would make sense.I have never been inclined enough to measure fuel pump lobe taper.. but they are designed to spin by simply looking at enough of them. I would say it's when they stop spinning that they will start to get trashed.
Kinda nothing. It doesn’t always work out that people have a good one on hand though so we’re discussing the flaws with replacements that often do fare too well.What is wrong with the stock ones that go 200k miles