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Discussion Starter #1
Hi all,

I have a new rebuilt engine spewing blue smoke out the left tail pipe after the initial startup and 20 minute break-in period - heavily at idle and somewhat less under throttle.

I ran the engine at 1500-2000 RPMs for the initial break-in then changed the oil. There were tiny non-metallic flakes in the oil filter but nothing large - the oil had a sheen. I did it a second time to set the timing and idle mixture on a warm engine. It started to smoke after this "session".

Today I took it out driving it hard varying my RPMs and using a heavy foot making a conscious effort to go up hills when ever possible on a 20 minute drive. I did not use wide open throttle at this time but I did get close. when I returned it blew large amounts of oil as I lined it up to pull back in the garage.

The rebuilt engine sat all winter as I finished all the ancillary installation tasks.

I did NOT check the plugs yet (engine was cooling), but unless this is a characteristic of a Pontiac rebuild I suspect a NEW ring or valve seal is bad or installed incorrectly by the rebuilder?

Any help would be greatly appreciated.

Thanks in advance, Dan

Because picture-less posts are boring...



 

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Discussion Starter #3
Plugs show near perfect burn.

Yea, I figured... figures.

Rebuilder says it's my tune, I'll do as he suggests but I'm not hopeful.
 

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You need about 500 miles to seat the rings and blue smoke is oil.
To check your tune run it until it is at operating temp, let it idle and shut it off.
Wait 30 seconds then just hit the key without touching the throttle.
If it doesn't fire right up then it isn't set up right.
 

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Discussion Starter #5
Thanks.

That's how it runs now - fires right up. I'll have to up the idle speed while in Park, it wants to die while backing up on a slight incline.

I have a friend coming over tomorrow afternoon who does this all the time, he will double check my tune. He also has a better timing light than I do (with total advance, rpms etc).

You need about 500 miles to seat the rings and blue smoke is oil.
To check your tune run it until it is at operating temp, let it idle and shut it off.
Wait 30 seconds then just hit the key without touching the throttle.
If it doesn't fire right up then it isn't set up right.
 

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Take it out on the freeway and run it.
It's all trial and error, I ran my goat out to Williams Az. and when I got there the points were fried so I went with a Pertronix replacement.
I had gone with a Comp Cam and the appropriate springs and on the way back I bent both pushrods on #3 in Barstow but gimped it home on 7 cylinders.
The Comp Cam rep didn't bother to tell me the stock pushrods were not strong enough for the lift and spring weight and I had to use Visegrips and a 3' crowbar to pull the bent exhaust rod out.
Pulled the intake and valley pan both lifters were laying in the galley, put them back in, new hardened pushrods and changed the oil.
Runs great now and oil pressure is back up to 60.
Most of my problems were due to a bad machine shop (CVMS) and lack of proper info.
You need to just run it and then do a compression check to see if it is the rings.
I also purchased a Greenline tach to add to my gauge package so I don't have to guess at where I am at on RPMS.
 

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Discussion Starter #7
I remember your thread on that... I hope I don't have to go through that sort of thing.

Tried to tune it yesterday, apparently the timing light we used didn't work. The timing mark ended up way above the 0 mark. I'll have to get a new light and start over - I never set total timing before, just set it at 9 degrees then let the distributor and vacuum do the rest. With a "slightly above stock" cam I'm told by the builder I need 28-32 degrees of advance when all is said and done.

I looked at instructions for setting total advance using a small vacuum pump (I have both a plug in and hand vacuum pump) but I'm unsure how much vacuum is needed for the test/setting procedure - like I said new territory for me.
 

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Set your timing light to RPM and with the vac plugged to the dist. look at the timing marks and watch it move as you increase the RPMs.
When it stops moving that is the RPM you are all in at.
This should happen around 2,700 RPM.
Here is a good thread, read Bear's post on how to find the sweet spot.
Once you find it dial your timing light and read the advance at zero and record it for future use.

Pontiac Street Performance - Initial Timing Question
 

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Discussion Starter #9
Interesting read, thanks. Looks like there area lot more than a few ways to skin this cat.

To clarify something first. I still want to set a base timing (mechanical) WITHOUT the distributor vacuum attached then use the distributor(engine) vacuum to set the total advance not an external vacuum pump (as the timing light manual suggests)?
 

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Yes.
First you need to find out if zero is actually zero TDC on #1 .
Dial indicator in #1 to determine accurate timing mark.
Second determine "all in" with vac unhooked and plugged.
I have a golf tee in my timing light case for this purpose.
These are the first steps, you may need stronger springs or weaker in the dist. ideal is all in at 2,700.
I used Bear's method after getting it close, pick a start and finish line.
I have an TH-400, pegleg with 2.93 gearing so it isn't a rocket off the line but I have it dialed in to the point where I have to be really light on the throttle making right turns from a stop to keep from smoking the tire.
What you need to do is run it as you have it and get the rings seated and broken in because it will change.
When my engine was fresh my disc brakes didn't work well until my engine was broken in and the vacuum increased.
Vacuum increases as the rings seat so that will change the tune as far as advance time is concerned.
You need to do a compression test to find out which cyl. is causing the smoke but chances are that will quit happening once the rings are fully seated.
As long as it starts easily and you are not experiencing detonation drive it, 500 miles minimum, a thousand miles is optimum.
 

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Discussion Starter #11
I'm almost 100% certain I had TDC at 0 but I'll double check again. Can't build a house without the foundation. :)

That being said, I'm using the stock or "one notch up" distributor spring weight - I can't recall which I used when I rebuilt the distributor before the engine rebuild.
 

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I would not worry about the smoke at this point either. Too soon to really know unless it is really excessive. It can take some time for the rings to seat. Not only do you want to do a few accelerations, you also want to do some decelerations to pull vacuum on the rings to add in their seating.

Here is one PDF on breaking in an engine. You don't want to "baby" the engine, or do an easy break-in as the rings may not seat, and may glaze over. For the bursts of acceleration & deceleration, you want to have the trans in 2nd or 3rd gear to put a load on the engine. Read this to get an idea: http://static.summitracing.com/global/images/instructions/atk engine break in.pdf

I would be more concerned if the smoke is still going on after 1,000 miles. Not saying you should not check a few things, but give it some time if everything checks out. :thumbsup:
 

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With your timing light set to RPMs run it up until it stops advancing with the can unplugged and the hose plugged.
Here is what I got testing the gold, silver and black.

After searching for the data on the Mr. Gasket kit for my distributor and finding no/conflicting info here is what I found.
The gold/copper colored springs were all in at around 1,700 and change, the silver ones all in at 2,100 and change and the black were all in at 2,700 and change.
I went with the black and timing at 34 at 3K.
 

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Discussion Starter #14
Thanks for all your help guys.

I got her dialed in this AM, for now. I took her on the highway for some hard pulls and high speed (with two passengers, full fuel tank, 200 lbs in the trunk). She ran great.

Next I need to locate my spring kit from the EFI upgrade and swap those in and out to see what she likes.

I didn't screw around with broken timing lights (friends didn't seem to work) and bought one of these - Equus 5568 Pro-Timing Light. It worked great.

Thanks again! Dan
 

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Discussion Starter #15
P.S. I need to fine tune the idle speed and idle jets again. Seeing how one setting effects the other is interesting - this being my first experience with tuning.
 

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Thanks for all your help guys.

I got her dialed in this AM, for now. I took her on the highway for some hard pulls and high speed (with two passengers, full fuel tank, 200 lbs in the trunk). She ran great.

Next I need to locate my spring kit from the EFI upgrade and swap those in and out to see what she likes.

I didn't screw around with broken timing lights (friends didn't seem to work) and bought one of these - Equus 5568 Pro-Timing Light. It worked great.

Thanks again! Dan

Glad the "problem"is solved. They often say run it like you are going to drive it. Just think about a drag car. They fire it up and wide open it goes down the track. No road break-in, just hard running. You have to seat the rings under both acceleration and deceleration using moderate driving and a few hard blasts. Also vary your speeds for the first 500-1000 miles - local driving is good. If you follow some of those earlier break in procedures of keeping it under 50mph for the first X miles and don't exceed X-RPM's, you may not break in the rings properly and then you wind up with an oil burner.

I also found this which might be a little helpful as well:

Keep the revs decent. You’ll need to keep some RPM figures in mind. Usually, diesels rev less than gas engine, that means we’re recommending you don’t go over 3,500 RPM on a petrol engine. Again, it depends on the engine itself. As a rule of thumb, keep it below the halfway point of zero and the redline. (it does not say for what period of time, but I might go with the 1,000 miles and then steadily increase your RPM's after that as you open up the engine).

At the same time, don’t baby the throttle, just be careful not to go over the aforementioned limit too often. While accelerating, do it with confidence, applying wide open throttle from low RPMs. (as I mentioned early, usually in 2nd or 3rd gear so as to put a load on the engine. 1st gear will just rev up too quickly and not accomplish what you want to do.)

One of the aims of breaking in an engine is making sure the piston rings seal against the cylinder bores. That is done using gases emitted during running that force the rings outwards. That’s why it is good to provide high pressure (and the suction of deceleration) initially.

Change the oil after 100 miles if you can. As I said, the reason while people break in engines is to remove the tolerances in the block. That means there will be small pieces of metal going around in your car’s engine and you should get them out.

Ideally, you should change the oil/filter the car came with after a short period (50-100 miles) and then again when the break-in period is over, at 1,000 miles or so. That way, you’ll make sure the ‘extras’ are gone and you car’s oil is as pure as possible.
 

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Discussion Starter #17
Thanks PontiacJim, the information is much appreciated.

Now I turn the key when it's hot (operating temp) and she fires right up! But... I've developed a ticking sound at operating temperature - especially after I ran it hard on the highway. I used a stethoscope to hear the lifters/valves clicking away but they didn't sound overly loud. Am I being oversensitive?

Some particulars...
I have the idle set about 800...
Initial timing at 12...
Total timing at 27...
I have rollers on a mild cam...
192 degree thermostat...
I'm on my second round of Brad Penn break-in oil (less than 50 miles on this round)
Dip stick is clean (oily) and does not smell like gas
I'm using the springs and weights that the car came with... I'm assuming the weights are original... the timing curve is fairly fast so I will probably go with the Stronger Weights Goat Roper mentioned above (later). I don't want to change too much at one time so I know what effects what.
 

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You using Polylocks on the rocker studs versus the factory nuts? Don't care for the factory nuts as they can back off and this may be where your ticking is coming from. Would not hurt to pull a valve cover at a time and watch the oil flow with it running. Don't need to run it long at all, just long enough to confirm a good oil flow. Might want to rev it up slightly by hand, just have some towels ready as it can get messy quick, so no need to run it any longer than necessary. Then do the other side. It's just peace of mind for you and you can see if a rocker has loosened up as you will hear it better with the cover off.

Could also be as simple as an exhaust leak which can give you that "I just can't find it" ticking sound. Check the manifolds and where the pipes bolt up.

It's ok to be concerned with any new engine. You'll learn the quirks as you drive it more. Remember, its not the cars of today where they are quiet like sewing machines.

I would also do a little re-torquing on the next cool down. Check your head bolts and intake bolts. They should be good, but better safe than sorry.

Everything else looks good.
 

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Discussion Starter #19
Thanks, I'll check the bolts for exhaust pipes and heads... Exhaust manifolds should be good, I used bolt locks on those.

I did find a "the extra long" water pump/timing over bolt had loosened so I'll need to put thread locker on that...

I didn't build the engine so I'm not sure what nuts were used on the rockers. I'll have to inquire.

Yea, I know they are not like today's cars. I've have a 31 year old truck who always gives me something to think about. :)

Thanks again...

You using Polylocks on the rocker studs versus the factory nuts? Don't care for the factory nuts as they can back off and this may be where your ticking is coming from. Would not hurt to pull a valve cover at a time and watch the oil flow with it running. Don't need to run it long at all, just long enough to confirm a good oil flow. Might want to rev it up slightly by hand, just have some towels ready as it can get messy quick, so no need to run it any longer than necessary. Then do the other side. It's just peace of mind for you and you can see if a rocker has loosened up as you will hear it better with the cover off.

Could also be as simple as an exhaust leak which can give you that "I just can't find it" ticking sound. Check the manifolds and where the pipes bolt up.

It's ok to be concerned with any new engine. You'll learn the quirks as you drive it more. Remember, its not the cars of today where they are quiet like sewing machines.

I would also do a little re-torquing on the next cool down. Check your head bolts and intake bolts. They should be good, but better safe than sorry.

Everything else looks good.
 

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If you didn't use anti-seize on your exhaust manifold bolts pull them one at a time, apply and re torque.
The last thing you want to deal with if you lose a gasket is a broken bolt.
 
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