new engine start up/break-in q's?

hey hey hey,
i just finished putting all the exterior stuff on my rebuilt engine and it will be going back in the jeep in a day or two. my questions are how do i start this thing up so as not to do any damage? could someone please give an accurate description of priming the oiling system? also, what is the best break in procedure? if there's anything i'm missing, please let me know, this is my first experience of doing this.
thanks a lot,
dan f.

If you're installing externals this is abit late, but I hope you primed the oil pump by packing it with vaseline. To start oil circulating, cut the handle off a long straight-blade screwdriver, chuck it into your electric drill, and stick it down through the distributor mounting hole to engage the oil pump shaft. Spin it up until oil pressure registers on the gauge.

When you start the engine, run it at a fast (1500 to 2000 RPM) idle for at least 20 to 30 minutes to allow the cam and lifters to wear in and work harden the surfaces. After that, drive it easy and avoid constant speeds for the first 500 miles.

I would change the oil and filter at 100 and 500 miles, but that may be overly cautious.

eagle, thanks. actually, everything is on except the pump, distributer and oil pan because i thought someone would have a similar suggestion. by packing the pump with vaseline, do you mean just filling it until it starts to come out? i'll do it, but out of curiosity, what does that do? thanks for the help, luckily the only person who answered my post always has reliable info.
thanks,
dan f.

You just split the case and pack vaseline into the cavity where the two gears are, then put it together again. All it does is provide something for the gears to pump out while they try to estanlish the initial prime and suck some oil in.

thanks eagle!

If the engine is all together, do not bother pulling the pan and all to pack the oil pump. You will find the pump will prime just fine without that step. I used to do that until i discovered it really did nothing, esp if priming it before cranking to start. Do get a drill and attachment that turns the correct direction that will mate with the oil pump drive so can be spun till oil pressure comes up. If possible attach a mechanical oil pressure gauge as a monitor.

Try to get everything dialed up so will start as quickly as possible when first cranking. The engine needs to fire up right away to come up to 1500 rpm min so as to assist with new cam break-in that is so critical. GM has a good camshaft break-in oil additive that is supposed to be really good. I am sorry i do not have that number at my disposal but would be worth looking into.

Limit engine rpm to at least 3000 for 500 miles and do change the oil then. Use a good organic 5W-30 oil for break in as well as afterward till totally broken in.

thanks for the info. i think i'll still do eagle's method because its still out. i'll also look for that GM fluid. one final question: i'm having difficulty getting the timing between the distributer and crank right. i just line up #1 tdc and the rotor pointing at terminal 1, right? is there something i'm missing or is there some kind of trick to it? i just don't want to have to keep cranking it with the wrong timing. thanks again for the help.
dan f.

On the XJs with EFI the distributor doesn't really control timing the way it did in "the good old days." Timing and injector firing are controlled by the CPS. The distributor more or less just ensures that when the CPS fires the ignition, the spark goes to the same cylinder that just got fuel shot into it.

To be strictly technical, there was a TSB out some years ago about "indexing" the distributor, and people who have used after-market cams have found that this is sometimes necessary because the cam distributor drive gear doesn't quite match up with OEM.

The procedure is to set the #1 piston at TDC on the compression stroke. Take an old (or new!) distrbutor cap and use a Dremel tool to cut out the side so you can see and access the #1 turret contact inside the cap. Set it in place on the distrbutor. The tip of the rotor should be beyond the cap contact post with a clearance of 0.020" (measured with an old fashioned feeler gauge).

Eagle said:

.....set the #1 piston at TDC on the COMPRESSION stroke....

Click to expand...

VERY important!!!

Both valves are closed for that cylinder.

thanks guys!