Any preferred methods for pre-oiling after rebuild prior to start up? Cam Info.

Sparks-IDI

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I'm putting my engine back together and as I'm working on it I keep wondering how do you prime it properly. On gas engines you could pull the distributor and use a hand drill motor to turn the oil pump shaft till you see oil and oil pressure. Kind of hard to do here with a gear driven pump without turning the motor over, a lot! It kind of makes me wince at the thought of cranking that much with no oil at the bearings right away. I did use plenty of assembly lube for all the bearing surfaces, but still bothers me. You have that long pickup tube, an empty pump, an empty oil cooler, ( you can fill the filter with oil though) and all the oil passages in the block. You could leave the glow plugs out to forgo the compression till you see oil pressure but it seems it would still take a fair amount of time "dry cranking". I thought about gravity feeding a bottle of oil overnight thru the oil pressure sending port at the back of the block, since it seems to be about the highest point. I would think that given a few hours the oil would more or less fill up the oil passages somewhat to help minimize how long before you get oil pressure. Guys that have done a full rebuild, what have you done for this? Am I over thinking this?

So i did not plan to completely disassembly my IDIT, just wanted to do a re-seal. Well, upon inspection I found a cam lobe going away. So I ended up fully disassembling the engine to see what else might be there. Engine surprisingly looks generally pretty healthy with minimal wear. No cracked pistons, piston clearances within service limits and the bearings also. So a re-ring, hone, cam, rod, main bearings, crank polish.

As far as the cam, I contacted Oregon cams and asked if they were familiar with the "logger cam". Ken, the guy I talked to wasn't sure what I was talking about, but he would check. He emailed me back saying they have the info for one cam grind for the 7.3 IDI motor. He called it the #1840 grind. These are the spec he sent me. 189/280 @ .050”, 243/233 adv, .284”/268” adv, 104 lobe separation. I have seen that 1840 number bounced around the internet so I went ahead and sent it off to them. Figuring what do I have to lose, the cam is junk as it is. This was the end of May. He said they were behind and it may take a few weeks. That's OK, I got plenty else to do.

They are still Oregon Cams but no longer located in Vancouver, WA. Their website still lists there location as Vancouver. Their new location is in Portland not far from the PDX airport, at least that is where he told me to send it. I know he got it cause I asked about the lobe and he indicated he has looked at it and said it should grind out. So apparently they have moved.
 

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Olds64

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From my understanding, this is the Oregon Cam Service that does the old logger cam.

Oregon Cam Service

Not to be confused with these guys.

Oregon Fuel Injection

I ordered a DB2 rebuild kit from Oregon Fuel Injection before. It came quickly and was a decent price.

I've never started a freshly rebuilt IDI. At the very least, make sure the fuel filter is full of fuel before starting the engine.
 

DirtyWood

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Not much help but the shop manual I have says this: "
Installation

NOTE: If. the engine'to be installed has 'been9verhauled
'or' has been' in storage, take' the following' precaution to
prevent piston and bearing scuffing. Prime the entire
engine lubricating system tq fill the bil.cooler, ·.oil, filter
and cylinder block galleries with the speCified type and
grade of oil.

The best I can come up with is either rotate the engine by hand or remove power from the IP and bump the starter. I installed an aftermarket oil pressure gauge and from a cold start after an oil change full oil pressure takes about 1.5-2 seconds.
 

scsmith42

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If it were me, I would use a pre-oiler for it.

Now they’re pretty expensive to buy, but you can modify an air-conditioning flush cleaning system to serve the same function for a fraction of the price. The main difference is you might have to refill the air-conditioning plus system two or three times during priming versus you wouldn’t have to do that with the larger pre-oiler.


You want to plumb it in to one of the oil galley plugs, such as at the top back of the block with the oil pressure sensor comes off or one of the plugs on the side of the block where they have oil galley located.
 
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headhunter38

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You can make your own oil primer pretty cheaply. Ive made one with a 2 liter soda bottle and it works. Put air pressure on the schrader valve to force oil up the hose. Something like this
 

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Olds64

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Excellent ideas! :thumbsup:

Here's a dedicated pre-oiler from Summit Racing. Definitely a bit priceyer than a DIY version. Don't forget though, "he who dies with the most tools wins!"

Let us know how the engine start goes.
 

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