[Catdaddy]

Hi,all. I’ve been on the site s while but couldn’t get logged in/pw reset so I started a new account. Anyways. I’ve gotten the 389 in my 66 Catalina rebuilt. Got the upgrade from butler performance for the newer water pump w the timing cover n new balancer. I set the TDC mark on the balancer at the 12 degree before mark on the timing cover. I was having carb mount/high idle issues when I first started trying to crank it up. Edelbrock carb. 600-650 cfm I think. Pretty sure I’ve gotten that better now. The issue I’m having is I have like grey/white smoke on the pass side and all my plugs are black and most look wet. They’re the ac Delco 45s gapped at 45 for the hei. Could I have just fouled them all out and now they just won’t clean out? Maybe one on the pass side just isn’t giving much burn off anymore n that where the smoke is coming from. Do the valves on these motors have to be adjusted/tuned? It runs good now.(haven’t gone for a drive yet w the smoke)timing about the same, carb idle 8-900, takes gas descent. lf the plugs were just black and I wasn’t smoking I’d take it up the road but don’t wanna push it. I know there are a ton of variable here and it’s not gonna be easy to diagnose this way but anything I can get to try from here, I’ll def consider. Thanks.

[Goatracer1]

Did you try cleaning the plugs? As for adjusting the valves, do you have a stock replacement cam or a high performance aftermarket one? If you have a stock cam and valve train you should not have to adjust the valves. If aftermarket HIPO you may have to convert to an adjustable valve train. A quick and dirty short cut is to use Chevy self locking rocker nuts and use them to adjust the valves.

[Catdaddy]

It does have an aftermarket cam. It’s a flat rapper cam. Dunno the specs. Dude said he’d put me a lil street cam in. Really regretting not just going w the stock cam. I have a set of NGKs imma put in but wanna check with the BP guys tomorrow about the timing set up w that timing cover upgrade

[steve25]

Where the heads rebuilt also , if so what new parts where used?
Where new valve stem O-rings used ?

Does it smoke pretty much as soon as you fire it up or does it take 5 minutes or so?

[Catdaddy]

Yeah, it has new valve seals. And it’s pretty much as soon as I fire up. A little lighter at first, I suppose.

[grivera]

Did you break in the cam?

[Catdaddy]

I thought it was just like steam, burn off from the thing sitting there for a year. The other side steamed off a bit but it cleared up. When I hit the throttle it gets heavier, comes up kinda slow n lingers there. Don’t spread out n dissipate very fast. It reminded me of what I saw one do when the carb just floods one with gas. I cant really smell a heavy gas smell, tho. Not in the condensation drip, either. And that’s not oily feeling or anything. I had to turn the idle screws down til they were only about 1/2-3/4 of a turn out to get my best vacuum reading. So, I dont think I’m super rich any more. They were both at the base 1.5 turns out before that. I did have my vac plugs backwards. The PCV was plugged into the manifold and trans n other vacuum hookup was on the carb base. Maybe I got oil into the manifold from the PCV? But why only one side? And again. The plugs look the same on both sides.

[Catdaddy]

I haven’t really had it running well enough where I trust to run up the RPMs for an extended time.

[Catdaddy]

It’s only ran at idle speeds so far. Beside the occasion push on the throttle.

[b-man]

Idling the engine is going to flatten the cam.

Get the RPMs up to 2000 and run it for 20 minutes.

If it gets too hot shut it down, allow it time to cool down then continue the cam break in.

The idea is to sling oil onto the cam and lifters so they burnish together.

Stop idling the engine until you’ve broken in the cam.

[Catdaddy]

I think it’ll handle that without getting hot, no problem.

[Schurkey]

Get a garden hose ready to mist the radiator if needed.

Shutting-off the engine after 10--15 minutes so it can cool is not a terrible idea. Then re-start and finish the break-in.

[lust4speed]

Don't know how your PCV valve is hooked to the manifold and whether it feeds to both planes like Pontiac did originally, but not a bad idea to pull the valve out of the valley cover and just let it lay there while you sort out the smoke.

You probably have the stock manifold? If so, the distribution for fuel is cylinders 2&6 from the drivers side of the carb and 4&8 is the passenger side of the carb* -- or in other words a carb problem would have both banks belching smoke. So I would rule out a carb problem.

Next pull the sparkplugs from that bank and see if you might have one really bad plug with the others fairly clean. That will narrow the problem.

* Possible that I switched around the sides of the carb but it's too cold tonight to go out to the garage and verify which side goes where

[steve25]

If it’s that cold in your garage that you can’t work on it at night then it should not overheat by running it 15 minutes to break in the cam, speaking of which I have a concern that it’s only seen more or less idle speed.

Cold oil will not flow and get kicked up like it should to keep the cam lubed up for break in.

Before you start it again I would over fill the pan with 1.5 extra QTs of a 5w 20 oil.

[Dragncar]

If you have fired that thing up and simply let it idle you could have already ruined your cam. Never, ever do that. Its fire up and immediately 2500 RPM for 20 minutes.And it id does not fire right up, stop cranking and find out why its not firing.
BTW, was this engine over bored ? The reason I ask is because 66 389s were notorious for cracking cylinder walls and over heating.
My dad bored out our 66 389 out and a bore eventually cracked.
And "this" is the reason 67 400s have thicker cylinder walls. PMD wanted no issues with the new 400.
I have a .060 400 and this thing just might have one more bore left.

[Catdaddy]

Thanks on the PCV idea. It hasn’t been bored that I know of and I run a bullet heater in my garage when it’s cooler. I can throw some extra oil in there. The upgraded cooling system will keep me cool. And if I’ve already ruined it, guess I’ll be having to learn how to do that job next. SMH.

[68WarDog]

Depending on how long you've run the engine with possible a rich ( wet/carbonated plugs) condition. It may be a good idea to drain the oil and refill 6.5 quarts, including new filter. Since you're changing the filter, it's a good idea to check the pleats for any metal.

[Schurkey]

Originally Posted by lust4speed

You probably have the stock manifold? If so, the distribution for fuel is cylinders 2&6 from the drivers side of the carb and 4&8 is the passenger side of the carb

Actually 2 & 8 are paired for one plane, 4 & 6 are paired for the other plane.

Outer two on one bank, inner two on the other bank are fed by each plane of the carb.

One plane will feed 2, 8, 3, 5. The other plane feeds 1, 7, 4, 6.

[Catdaddy]

Got the break in procedure done yesterday. Put in the fresh break in oil plus a little extra. Swapped out the plugs n let her rip. She did just fine. The smoke slowly trailed down. When the break in was finished, it was still smoking just a little. Gonna change the oil again n go on for a short ride. See how it goes. I need gas in it, anyways. We’ll see what happens.

[steve25]

Fingers crossed for ya.