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Onefast99gsx
06-06-2007, 09:03 AM
Hi guys-

I hope to start my car up for the first time later this weekend. It's a fresh rebuild. I packed the oil pump full of vaseline and of course used assembly lube on all the bearings. Other than adding oil do I need to prime the engine somehow to get oil into all the journals and head?

My engine shop said they have some sort of system where they put a quart of oil or so in this container thing and hook it up to compressed air and tap into one of the plugs on the oil filter housing and it shoots oil into the motor. Do I need to goto that extreme. Don't really want to push all the assembly lube out prematurely.

btw- I redid the timing belt tension like 6x until I found exactly where I wanted the tension. Then of course each timing you have to rotate the motor over and let sit for 15min. So I'm sure the cyls are getting dry. I didn't get the engine in last night like planned. Would it be a dumb thing to add oil as normal, then physically rotate the motor upside down or close to it for a second in the engine stand?

Thanks.

1ViciousGSX
06-06-2007, 09:12 AM
You can prime the engine by spinning it over with the sparkplugs removed and fuel pump fuse pulled until you see oil pressure. Do it in 10-20 second intervals so you don't overheat your starter. Put the plugs and fuse back in and fire it up.

Then drive it like you stole it.

Onefast99gsx
06-06-2007, 11:15 AM
According this old statment of JET's I should have spun the oil pump also. I probably should borrow that thing at my engine builders shop that uses compressed air and oil and shoot it into the oil filter housing. Dam I don't want redo the timing belt.

---
yeah, spin the pump while it is out of the car, then do it again when it is in the car and you are ready to fire it up. Break-in is way overratted. Most of it happens in the first 20 miles if you had a good plateau bore hone done. Mine went on the dyno with 23 miles on it

I would recommend 200 miles though. http://www.mototuneusa.com/break_in_secrets.htm

JET
06-06-2007, 11:19 AM
Do like Vicious said, that is basically as good as spinning it with a drill out of the car. It definitely isn't worth a tear down to do it.

Onefast99gsx
06-06-2007, 11:24 AM
Thank you JET. I was hoping one of you logged on soon and posted something so I could stop checking the site so much while at work :)

The only extra thing I was going to do was minutes prior to starting, add all the oil with the valve cover off. Dump it all over the cams and valve train and bolt the VC back on and then do what Vicious said to do above. The crank will already be rotating in oil when cranking over. Then just a matter of oil getting on the cyl walls.

Thanks guys.

tim
06-06-2007, 10:42 PM
You can prime the engine by spinning it over with the sparkplugs removed and fuel pump fuse pulled until you see oil pressure. Do it in 10-20 second intervals so you don't overheat your starter. Put the plugs and fuse back in and fire it up.

Then drive it like you stole it.

I have heard to do this also but I am curious why you would? How is it any different than just starting it? I realize you wont be firing this way but just idling after the first fire up shouldnt be much load on the bearings.

Not trying to disagree just trying to understand why.

Goat Blower
06-06-2007, 11:26 PM
Because by doing this you're not putting any vacuum or decent cylinder pressure on the rings or rotating assembly. It's probably overkill, but it's easy to do, so why not. I always spin my oil pump with a drill with the engine on the stand, but this does the same thing. I leave the valve cover off and spin the motor until oil shoots onto the cams.

Swifty1638
06-15-2007, 09:29 AM
I've always spun the motor over without the fuel. I also have my pumps on a switch, so it helps ;) Assembly lube pretty much takes care of the "wear and tear" on initial startup. It eventually disolves and the oil takes it's place. Still, priming a motor is cheap insurance on your investment, and it's soo easy to do, therefore, why not?

-A. Swift