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Topic Review (Newest First)
01-06-2013 06:47 PM
BuzzLOL .. Yes, thumb can be used if you feel definite pressure as #1 piston comes up...
01-06-2013 05:05 AM
bsa_bob2 I have the timing mark @tdc.verified by the sparking -plug. ?holding the thumb on the #1 cylinder? is this the same thing? bob s
01-05-2013 08:37 PM
BuzzLOL .. The cam/distributor rotate ONCE for each TWO revolutions of the crankshaft... this means the rotor can be pointed at #1 sparkplug terminal, but the crankshaft actually ONE full turn off while reading TDC on the pointer/damper...

.. When crank is proper, both valves on #1 cylinder will be closed, and the cylinder will hold air if pressurized with an air hose... (don't let the crank rotate from the pressure on the piston)... then rotate distributor till rotor pointing at #1...

.. Make sure gas in carb. (hold temp. tank above carb. till it's full)

.. Make sure spark at plugs as engine is rotated...

01-03-2013 04:28 PM
Originally Posted by hcompton View Post
The back fire makes me think the wires are still off. Or something in the ignition is wore out or corroded.

Check the coil wires and the coil ground. Bad grounds will make the timing all over the place.

I would go over all the wires again amd make sure the firing order is correct for that car motor and year. Just to be sure its not an odd firing order.

Did you replace the cap rotor and wires or just clean them up.
The wires were pretty good but not great. cap was new 8 years ago,wires probably the same. I will check that firing order again far as grounds the gauges work on the dash, i checked continuity most everything. Tomorrows another day. I have got to be really close at this pointP.O had the wires start out to far around clockwise on the dis; cap i moved all the wires back around to where they should be. when number one cylinder is up.back fire on the right bank means one of those wires on that side is wrong...aaayy ?

yes i'll go thru the diagram in the book again.Sure is easy to throw money at this kar.must be getting cheaper in my old age thanks bob s

i realize those aren't the best pics. i can get more if needed .

ps "coil ground"............. would be tthe coil holder to the intake manifold right???????thats loose at this time.
01-03-2013 02:53 PM
bsa_bob2 tHis is the only picture i have just shows the motor,and the small gas feed tank hanging up there to the right. I pulled the dis;and went thru the spark plug wires. I moved the distributor to;[pointing at number 1/@tdcon the harmonic balancer, now i have started, squirting carb spray .gas. I advanced the timing just a touch, ccw, this makes the motor want to hit more. Now i have to let the starter kool down .so it stays alive long enough to hear this motor run. Also i am getting a Back fire thru the right side exhaust pipe. Nothing much has come out of it.It has started to .........TRY TO START............... ,everytime now. It gets A little closer each time i advance the distributor. btw the po had it in wrong , the wires now are lined up with the plugs as they should be. thats about it. I am increasing the timing more. Ihave poured alot of gas.with the squirters in the carb ,besides the starting fluid. i am afaid of diluting the oil to much its up about a half a qt.And its thin [not awful thin] there you have it bob thanks for coming back its truly appreciated the pics should be with this post
01-03-2013 09:35 AM
Originally Posted by hcompton View Post
If you can just loosen the bolts that will let it start. You only need a small gap around the pipe and manifold to allow enough air to start.

But i have really never seen an engine fail to start from crap in the exhuast. No i have seen some potato jobs but the taters flew out like bullets on the first pop from the engine. Not really sure you would be able to plug the exhuast so it will completely stop the engine from running. they usally fire a few times around.

If so just saws all the pipes after the manifolds and be done with it. if they are clogged then it wont matter since they need to be replaced anyway. Strange that the pipes would get clogged and not have any rust from sitting in a swamp. Usally things rust out very quickly.

pressure wash the car and engine. then use a steam cleaner to get the engine and other body sections free of crap you dont want to touch. steam will take everything off. paint skin whatever you stick in front of it. Using some clorox in the pressure washer will also help clean things up a bit. best to clean it and strip it out before the car is lost.

I would think the problem is not in the exhuast at all. but fuel or spark.
The kar is pretty rough but saveable. I hope the motor is as good as it looks. thanks for the tips bob s
01-03-2013 08:53 AM
Originally Posted by killeratrod View Post
So do not remove the manifolds & remove the 2 bolts on each side that hold the y pipe. this should be easy spray them today remove & start tomorrow .
Well i have some news i have found that the distr; is in wrong one tooth off. Wire fell out ,and some are green with corrosion.I will try this first. The po put a DIS clamp on it that is the wrong one. So i have to get one somewhere today.I'll prolly get it to run i don't know , when it does lite. i won't know what i did. Thank you guys for helping me.In all the years i have stored my kars i have never had a mouse get in a T/p? do you put a rag or a tennis ball in your cars while stored?never crossed my mind til i started on this kar thanks bob s
01-03-2013 08:15 AM
killeratrod So do not remove the manifolds & remove the 2 bolts on each side that hold the y pipe. this should be easy spray them today remove & start tomorrow .
01-03-2013 07:31 AM
vinniekq2 348 is a bb mark I, If its not safe to work on?(doesnt make sense,because someone had to install battery,check points and fuel etc) I dont see how removing exhaust bolts would be any more dangerous than the previous prep work. and if the bolts break,so what,they have to be dealt with at some point in time
01-03-2013 07:25 AM
bsa_bob2 Iam trying to stay clear of that.reason being. the bolts aren't going to come loose easily The bolt heads .themselves have gotten pretty rusty. anything els possibly.?
I am abit afrid wo work on this car......reason for that is this "hanta virus" that can kill you .i think is abundant in this car. A guy gave me the kar........i probably shouldn't have said yes.My addicted to making these old sbc engines run.being this "348"is A good motor.
01-03-2013 07:01 AM
vinniekq2 unbolt the manifolds from the heads and see if it runs?
01-03-2013 06:51 AM
Originally Posted by vinniekq2 View Post
what makes you think the exhaust is plugged?

This kar set in a marsh .when i loked inside there was two remains of skunks.the interior wasnothing but foam rubber and material
PIECES It was lived in by more than one raccon. mice crap absolutely everywhere .The engine compartment was repinted to the extent that it had been taken out to do this.The exhaust system .is like it was installed yesterday. I AM not sure or saying this is the problem.I know potatoes stuffed up the t/p wil stop a a motor. but this has to be mice. nests etc.
01-03-2013 06:17 AM
vinniekq2 what makes you think the exhaust is plugged?
01-03-2013 06:15 AM
348/chevy -may have plugged exhaust??????

I have been trying to start this motor for a Couple weeks now.I think i may have some plugged or/ partially plugged pipes. Is there any home remedies,for cleaning them out? OR i just cut them off up by the head pipes?Don't want to do the latter til i had talked with you guys...........any less drastic measures ? i can try????
Have any of you had this..everything else is [new plugs, great fire. I can't just haul this car out to a a shop,do to snow and ice.trailer froze down.took for of us to break it out of the ice o/s. winter never sleeps.chime in please.................... bob s

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