Thread: 350 SBC 180 out of time and still run?

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Hi all,

My first post here, thanks for having me, and Merry Christmas!!

MY son recently got his first project ~ 68 chevy c-10 truck he is going to rat rod. It contains what we beleive is a 350. We cant get to the casting number, but according to the head casting number and huge dampner, it appears to be a1971 350. unknown miles on engine.

Anyway,, we were told by a previous owner that the carb needed rebuilt, the engine has a mild cam, and she ran rough, needs a tune up!
We got her home and she does run rough!, fuel line was kinked, fixed that. checked wires with firing order, two wires crossed, fixed that. It has HEI distributor (Accel) and wires.
THe engine is also sporting a chrome timeing cover, elebrock performer manifold and Eldelbrock performer carb.

The engine is running but not well. Mild cam? all the aftermarket parts, someone def had thier hands in this engine. We are trying to get her right.
One issue I hope you can help with is this: We attempt to set timing, timeing light connected to wire #1 no timing mark. We end up finding the mark 180 degrees from where she should be.
We used a compression tester to find Top dead center on cylinder number one. When we get the pressure on the up stroke the timing marks is 180 degress off. The distributor rotor IS pointing to #1 wire at TDC. ??????????? Are we 180 out? is the dampner installed wrong? timing gears out? will a SBC run 180 degress out of time?

I have video of the engine running, and its not running terrible but its not running great!. It starts rough, smooths out a little when warmed up. She has a donut gasket leak at the manifold we have to fix yet. Engine does not tick, knock or backfire when it runs.

Pulled two plugs and its wet with oil/fuel. When she runs she spews white/gray smoke like its running rich.

The old oil smells like fuel. Changed that.....

Could this be a carb issue?
I am obviously a backyard mechanice but I have played with SBC's for years but this one I am confused.

Any direction or help is very much appreciated! I will try to post the videos of the engine running, running under load, then the exhaust while running.



Thanks again!
Robb

Hello Robbp, welcome to the club.
Regarding the damper, it could either be for a van, some were timed from underneath I believe.. OR, the outer ring could've spun. Will the engine run with the distributor 180 degrees out? No. What you can do is verify # 1 at TDC, and remark that spot on the damper. RSpears on this site has a cool way to verify tdc, when he comes along maybe he can share the link to it again? Then, If you have (or can borrow) a degree wheel, you can plot out before tdc and after tdc.

But you're probably better off verifying that the outer ring hasn't spun before doing all that... And I'm thinking you need to do a lot of verifying.. things like the valve lash settings, spark plug gaps, vacuum lines for cracks or breaks, fuel filters for debris... things like that.

Sounds like many hands have been in that soup and you need to know what is right or wrong with no assumptions. Do you have a vacuum gauge? I have a feeling you'll need one before this challenge is over!

Welcome to CHR! Here's the link to the thread Mike was talking about - Finding TDC I agree you need to get back to basics on this one and work through step by step. Good luck, and Merry Christmas!!

And IMHO you should scrap anything on the engine that you either know or suspect is Accell.

My chevelle is sporting a shiny new summit HEI because the guy whom looked at it was prejudice against accel. It didn't fix the trouble, because the accel dizzy was just fine.

With all the symptoms you are saying, my knee jerk reaction is to pull it and inspect it to the last nut and bolt. That truck has enough room for two motors in there, pulling it is a snap.

Realistically, if you wanted to rebuild it, you would already have it out, so look at what you know already: the previous owner said to build the carb, and the old oil smelled like gas, so start there.

While the carb is being built, confirm tdc compression stroke, and make yourself a new mark on the harmonic balancer. I'd also say to pull the balancer, and inspect it, try to determine if it has spun. Maybe even confirm the block number and order a new one that you know will work.

Check under the dizzy cap for corrosion or cracks, etc. With it running, pull each wire at the plug, and look for the spark. You can even use an old plug, ground it on the block. Careful, HEI stands for high energy, and kick out 30,000 volts, and it smarts.

Keep up posted.

Blue smoke = oil burning
Black smoke = rich - too much gas
White smoke = Water vapor - gasket leak or warping

As Scooting points out above, with the color of the smoke I'd do a compression test, you may have a blown head gasket.
Also, a bad vacuum modulator on an automatic can cause tranny fluid to be sucked into the motor, which yields a white/gray smoke.

.

I just remembered a 350 in a 64 C10 I got once upon a time, was running like ka ka. It had too big a cam for stock heads, and the studs were pulling out. If you have this, it will be indicated by valve tick.

The first thing to do is, verify your number 1 cylinder is on TDC by the position of the valves both being closed and piston is at the top on the stroke. If you cannot see the timing mark, and the rotor is not pointing to number 1 you have an issue. If the pointer is pointing to number 1 on the distributor, you are good here, if you cannot see the timing mark, your harmonic balancer has most likely spun on you, and you timing marks are off. You will need to make your own, so you can set the timing. You can use a piece of bent wire coat hanger, if the factory stamped metal timing marker is missing, or, if you have a small piece of sheet metal, you can get a bit more fancy and replicate what was there. With a chisel, put a heavy dent in to correspond where your TDC mark will be, as your engine is still, or should be now at TDC.or 0 degrees and bolt this new pointer to your timing cover. This will now give you a place to set your timing from. All the other advice you were given was also very good too, especially the part about the compression check, and carb rebuild. It seems to me, when some one decides to go deep into an engine, and cant even get the plug wires back on right, that is cause to worry about other things they might have done inside too.

IFFFFFFFFFFFFFFFF----------the mark is 180* from where it should be AANNNNNNNNDDDDDDDDDDDDDD its running rough----------you probably are not on #1 cylinder (Chev 350 #1 is driver side (in USA) and front) or the plug wires are still on the wrong plugs or maybe even both-----------