Another Engine Rebuild Thread - 80 3.0L

[Gunter]

Originally Posted by mca

Do I need to be worried about oil temps when I first crank it up?

Just thought about that this morning ... 15-20 mins at 2000 - 4000 rpms ... hot garage ... hot summer ... hot south.

20W50 plus EOS should do it.

You could get 1 Quart GM-EOS from a local GM dealer and pour it into the oil tank before you fill the rest of the oil.

Auxillary trombone or radiator oil cooler will only work with air flowing though them. If you like, you can put a small fan into the right wheel well and point it at the cooler. Not sure what difference it would make?

[mca]

Excellent. Thanks for the oil tips.

I do have the finned elephant racing lines installed and a carrera cooler in the front passenger wheel well (no fan though).

As you can see in my pics, I have a huge industrial fan in my garage. I could either direct that over the engine or at the carrera cooler.

[wilke3169]

Craig, One thing you may consider is to push the car out of the garage. Not a huge help for the oil temp, which will likely get hotter than norm. This is just because everything will be new. But the smells and smoke, etc. will cause wife and small animals to complain. The fan would do best over the cooler I would think. The engine fan pulls plenty of air across the engine itself.

[Gunter]

Leave yourself lots of room around the engine because you'll be busy looking at top and bottom for leaks.
The car is best left on stands for the run-in so you can get at the bottom.
Keep a set of wrenches handy, rags and a fire extinguisher.

[mca]

Originally Posted by wilke3169

Craig, One thing you may consider is to push the car out of the garage. Not a huge help for the oil temp, which will likely get hotter than norm. This is just because everything will be new. But the smells and smoke, etc. will cause wife and small animals to complain. The fan would do best over the cooler I would think. The engine fan pulls plenty of air across the engine itself.

Ya, we are looking at mid to upper 90s this weekend. I hope it won't be that hot the following weekend when we crank her up.

I will rely on your sage advice as to whether or not it is a good idea to break it in with this kind of heat.

[mca]

I took my current engine for its last drive this morning before removing the oil.

It was the first time that I used the purge valve on my finned oil lines. It worked out quite well - lots of additional oil was forced into the oil tank and out into my bucket.

Anyhow, the important thing is this ... I was wondering if I should disconnect my decel vavle during the first break-in drive?

With the valve connected, it really slows RPM drops between shifts. Opinions?

[Gunter]

I don't see any reason to disconnect the Decel Valve.
It is unlikely that the mixture will be right on start-up meaning you'll be busy adjusting as the engine coughs and sputters; keep it on the rich side and watch the oil pressure!
The important break-in occurs during the 20-30 Minutes of running before the drive while the car is still on jack stands.
During that time, revving up and down, after the engine is hot, begins to seat the rings in the lands.
The first drive with varying RPM's continues that process.
If the rings don't seat during the initial start-up, they won't seat later IMHO.

I suggest that you soak all injectors submerged in a small can filled with injector cleaner for couple days and blow them out with air.

[Charlie V]

Originally Posted by mca

Anyhow, the important thing is this ... I was wondering if I should disconnect my decel vavle during the first break-in drive?

With the valve connected, it really slows RPM drops between shifts. Opinions?

Mine is always disconnected. But then, I'm not a tree hugger.

[mca]

Originally Posted by Gunter

I don't see any reason to disconnect the Decel Valve.
It is unlikely that the mixture will be right on start-up meaning you'll be busy adjusting as the engine coughs and sputters; keep it on the rich side and watch the oil pressure!
The important break-in occurs during the 20-30 Minutes of running before the drive while the car is still on jack stands.
During that time, revving up and down, after the engine is hot, begins to seat the rings in the lands.
The first drive with varying RPM's continues that process.
If the rings don't seat during the initial start-up, they won't seat later IMHO.

I suggest that you soak all injectors submerged in a small can filled with injector cleaner for couple days and blow them out with air.

Ok, couple of questions.

1) Why would the mixture need adjusting?

The CIS is on my current motor and is properly adjusted. I am going to pull it off of the motor, replace the intake boots, change the injector o-rings, and clean it up some ... then put it on the new motor.

I understand that the mixture may change if there is currently a leak around the intake boots or injector o-rings. But if not, why would the mixture change? I guess that a tired engine could require a richer mixture ... but I don't see it being off too much.

Also, wouldn't I rather it be a little lean than rich? I thought that a rich condition would quickly wash away the oil on the cylinder walls.


2) Are you suggesting that I rev the engine during the 15-20 minute intial run?

I thought that I was supposed to get the RPMs up over 2000 using the bypass screw and then leave it at that for 15-20 mins. Have not read that I am supposed to vary the RPMs

[mca]

Originally Posted by Charlie V

Mine is always disconnected. But then, I'm not a tree hugger.

I actually prefer it connected. I like how it holds RPMs up in between shifts.

We should use more plastic b/c we need to save the trees ... oh wait ... now plastic is bad and will be the ruin of the world.

[Gunter]

If your'e lucky, the mixture will be alright, hm.........maybe not.

Different engine builders use different ways to break in an engine.
After initial start, I watch the pressure, leave it running for about 10 Minutes at 2k, then rev it up and down between 2-4k for a good 20 Minutes.
Change oil.
Go for a drive with lots of revving up and down meaning I would stay in 3rd, rev up to 4-5k, then lift off and let the car push the engine; do the same in 4th for many Miles.
The rings should be seated by now.
After the drive, I just replace the filter and keep the oil for another 2-3k Miles.
Do what makes you feel good because there are variations by different people.

[mca]

Originally Posted by Gunter

Do what makes you feel good because there are variations by different people.

Ha ... yes, many opinions out there. I like the idea of keeping it at 2k for 10 mins and then varying the RPMs for 20 mins after that. Seems to make sense b/c it will help seat the rings at varying RPMs.

I always wondered why you would keep it at constant RPMs during the first 20 mins ... then vary the load on the first actual drive. Seems like the first 20 would be more crucial for allowing the rings to seat throughout the RPM range.

Thanks for the tips.

[Elombard]

I would say there is a very good chance the mixture will be off IF you find all the leaks. There is a million places to get an air leak on the CIS. DOnt forget the breather system to the oil tank is an air leak for the CIS and will screw up the mixture. There is a good chance that your new motor will be tighter or you will find a split hose or loose clamp and eliminate that leak on the re-install and then the mixture will be toast.

One suggestion pull the rubber hose that runs from the oil tank to the back of the Throttle body on the currently running motor and plug the hole on the T body. Then adjust the running like that. I always got a lot of leaks from that system for some reason. I also found that it ran better on a tired engine without out all that oily smoke going back in the intake (but that is another story).

Any way its just one less leak to worry about. You will need to add a breather and catch can for the port off the old tank where the above line was or it spews all over your engine compartment.

Also, what ever you do dont inadvertently plug the oil tank so it cant breath some where. It operates under pressure and you will get leaks that you never knew were possible.

I guess one way to check your system is pull your oil cap off your existing running engine and if the RPMs drop you are OK for the most part. IF the RPMs dont change you have an air leak that some one has dialed the CIS mixture in to work with.

[mca]

Originally Posted by Elombard

I guess one way to check your system is pull your oil cap off your existing running engine and if the RPMs drop you are OK for the most part. IF the RPMs dont change you have an air leak that some one has dialed the CIS mixture in to work with.

I drained the oil today ... so no more opportunities to adjust things on the CIS.

Removing the oil cap creates a strong drop in RPMs. Never had any issues there.

[Elombard]

Youll be fine. I have never run in a new engine but my worst fear has always been some problem with the ignition or injection that I cant figure out and I cant keep it running for more than a few secs or it wont start :-) I have night mares about screwing up the rings, bearings, cams and rockers on a fresh rebuild because I cant keep it running......

I guess I am a candidate to have a pro do the rebuild/run in so I dont worry about it.

You must be anxious!!

[mca]

Originally Posted by Elombard

Youll be fine. I have never run in a new engine but my worst fear has always been some problem with the ignition or injection that I cant figure out and I cant keep it running for more than a few secs or it wont start :-) I have night mares about screwing up the rings, bearings, cams and rockers on a fresh rebuild because I cant keep it running......

I guess I am a candidate to have a pro do the rebuild/run in so I dont worry about it.

You must be anxious!!

I never really considered that possibility. Maybe it is b/c I know that my current system is running fine and all I need to do is replace the engine . Gives me a little comfort at least.

Yep, anxious but still a lot of work ahead of me. Dropping the engine, pulling CIS and cleaning it, pulling exhaust, etc.

[mca]

Old engine came out today. Kevin came over early in the morning to show me the ropes. Took about 2 hours to get the engine out. Another hour to get the tranny out. I think ... it was all kind of a blur.

Everything went silky smooth. Dirty but smooth. I did find that I need a new clutch as it was pretty worn. Here are some photos.

The required photo of me inside of the engine compartment.



Old engine.



Tranny and Kevin's greasy handprint.



Underneath.



Garage.




I still have tons to do before the install next weekend. Almost there!

[911 tweaks]

Great job there mca !!
Can you do me a favor... can you take 3~4 pics of the cis on the engine... top view looking down, all 4 sides as front back, r & l side... please
This would help me greatly as I am cobbling together a cis sys from many systems... please refresh my memory what yr this engine is coming out... 81 maybe ?
Thanks in advance, I hope, as these pics would be a TON of help to me... see my pics of where I am... "now where do I begin ??
Thanks
Bob

[911 tweaks]

here are my pics...

and

[Gunter]

Originally Posted by mca

Old engine came out today. Kevin came over early in the morning to show me the ropes. Took about 2 hours to get the engine out. Another hour to get the tranny out. I think ... it was all kind of a blur.

I still have tons to do before the install next weekend. Almost there!

Tight time table.

Flywheel grind?
New Sachs Power Clutch would be nice.

Now is the time to check/replace some seals on the transmission.
Condition of the guide tube?
Recondition the cross shaft, new bushings, seals.
Check the release fork for wear and cracks.

Check/repack the CV's?

Rebuild the starter?