bbjordan
Snow Monkey
I love happy endings.
I love happy endings.
Gary, thanks for sharing Russ' idea about shimming. My rebuilt engine, with a new Ford/IHC oil pump and a freshly cleaned and o-ringed oil cooler, makes 35 psi cold at idle. This is really great, except the oil pressure never goes above 35 psi and actually drops to 25 psi when the engine warms up. I gotta tell ya, I really hate the thought of pulling the oil cooler, but it's either that or the relief valve inside the oil pump. So, I'm betting regulator. Problem is, those parts (spring, header, valve) are no longer available. I contacted Discount Ford Auto Parts (dot com) because they had a header (E4TZ6881B) listed for $213. Nope, no such part in stock. The counter guy asked if I minded holding for a few minutes and he'd scan national parts inventories for dealers and Ford warehouses. Came back on the line and said no such number anywhere in the US. He mentioned that there might be an NOS header sitting in a box on a shelf in some dealership's parts room, but good luck finding the one person who would know about it.What usually happens is the spring wears down because its rubbing on the valve. As the spring wears down to about half the wire thickness you loose oil pressure because you loose spring pressure. Shimming it wont help for very long either. Shimming a new valve is the only way to make more oil pressure. I bought a new header and added 60 thousands of shims by making them from stainless steel washers. I learned that from Russ.. Typ4.. Neet trick too.
Thanks for the reminder, Russ. No second thoughts about pulling the oil cooler. There's nothing to be gained by pulling the pan. Gotta tell ya, that doesn't hurt my feelings at all!There is no regulator in the pump, it is all done in the rear header.
Yup, mine starts at close to 40 and then drops as the engine warms up. Problem is, the 'idle' oil pressure doesn't increase. What you see is what you have for the entire rpm range. 30 - 35 psi is just too low for my comfort zone. Even though the spring is old (30 years/300K miles) I'm going to shim it. Gary's concern is that the fix won't last. I understand that and view this as a temporary fix that buys some time while I find a good replacement spring. I'm thinking about shimming more than your original 60 thousandths. Maybe .080" or .100". I want to make up for the original weakness and get running pressure around 50psi to 60psi, but I don't want to get crazy.I have the opposite issue, 42 psi hot going down the road and 10 ish at hot idle, I want it a little higher, so some day ill pull the header and shim it to see if it is that or just the clearances, pressure has not changed in 100k.
Good point - I'll check the outer diameter of the spring real closely for wear. If worse comes to worse, I'll use the spring out of the 'new' cooler. That'll create a bit of a delay, because I want to show that spring to the mechanical engineering guys and the Auto Technology guy on the other campus. Oh well, that'll give me more time to polish chrome. Or something.Ok. When you remove the valve and spring look closely at the wire the spring is made from. If its worn flat on one side then you will have an issue with gaining any pressure no matter how much you shim it. If there isn't enough material to make it flexible then there wont be an increase in pressure.
For washers, I'm gonna go with mild steel washers with the same OD as the spring. And you're right, I definitely don't want to overdo the spring loading, because all that'll do is increase oil flow back to the pan. Ya know, here's a thought - slightly higher than normal oil pressure out of the cooler would be a help with an add-on bypass filter. I could tap off the inlet side of the filter from that plug located on the front of the rear oil cooler header. hmmmmm.......Now about adding shims. I used stainless steel washers that I needed to grind down the outer diameter to fit in the regulater valve under the spring. Also adding too much can lift the bypass valve in the top of the filter header. That bypass is there in case the oil filter plugs up. Dirty oil reaching the engine is better than no oil reaching the engine.
Actually, I see some logic here. The grit and crud falls back into the oil pan. The oil is at operating temp (HOT!) and all that nasty stuff drops through the thin(ner) oil and settles on the bottom. The pickup tube pulls supply oil off the crud-free stuff at the top of the pool. That's really not a bad idea!My 1937 Cord engine has a floating oil pickup so it only sucks the clean oil on the top of the oil level in the pan.. Gees how things and beliefs have changed. Today we all know clean oil is pumped thru our engines and then the dirt it picks up is washed back into the supposedly clean oil on the top. What were those engineers thinking back then.