Well....went to take the car for an inspection sticker and maybe do a few things to it on my day off. Got in, started right up, idled for an bit then died. I had a sneaking suspicion and pulled the distributor to find the gear still sitting on top of the oil pump shaft. This is the second one I've sheared a roll pin within a couple hundred miles or so and I'm beginning to get annoyed. Motor is new with about 2K miles on it. I'm using Valvoline VR1 10-30 and the big money TA cover that I ran on my old motor. What say yee?
Something is clearly binding. What's your oil pump end play? When the first one went did you see any scoring in the pump assembly?
I didn't. I'm I didn't. I'll check when I get back to the car and am unaware of the end play. All I know is the TA cover was left as it was when they sent it to me.
Using the grid Scott Moody sent back with my recalibrated factory gauge, the needle is a hair above the "H" which calibrates to right above 60 lbs.
Where are you sourcing the pin? Is it a clean shear or is the pin loose and working its way out first?
I had a box of them I've had for a while. Are there different ranges of quality roll pins? Sheared clean off.
I would assume they come in all sorts of different grades. There must be a difference between the distributor roll pin and a pin that simply holds a cabinet handle in place... the cheaper ones probably are not hardened..
With a 60 lb. sender, a bit above H could be anything over 60. For all you know, it is 90. If you have an adjustable regulator, back it out.
I sheared 2 myself. Then I stopped using the cheap harbor freight ones i had in my garage and used some old American made ones I found a Ma & Pop hardware store. Been on for 9 years now.
My point is a 60 lb. sender pegs the gauge at 60 psi. It can't go any higher. So 70, 80, 90 psi will produce the same reading.
Larry - At what pressure would you expect the pin to shear? Brett - Might be a good idea to put a gauge in the sender hole and see what you actually get on cold startup.
Depends on oil temperature, RPM, and pressure. If you rev the engine to 4000 at 60 psi, it might shear it with cold thick oil, or it could do that at half the RPM at 90-100 psi. I think it is a good idea to see what the actual pressure is. For all we know, it's at least 60 psi, maybe more, maybe a lot more.
Had one shear off my Mallory comp 9000 years ago at a cold Friday night race ..oil got a bit cold between rounds ,sheared off at 60ft ..fixed it at the track then at home drilled the gear and distributor larger for a bigger pin .that was about 17 years ago still working