Thread: Sbc Chevy have no idea what's wrong

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Hi everyone I'm new to this site. I have a 95 350 that I tore down and inspected and resealed it appeared to be a good engine. .... So I timed it can at 6 crank at 12. Now can at 12 crank at 12 I have to spin my crank 180 degrees almost to have number 1 tdc. What am I missing please any help will be greatly appreciated.

what do you mean by reseal? What do you mean by CAN? Did you change timing chain or gears? Do you know what the firing order is and what cylinders are numbered???????

Yes I mean cam, I honed the cylinders and gapped my rings and just checked everything out yes new chain and gears a set from comp it's a sbc 350 firing order should be 18436572 but again timing marks line up but number one cylinder is still not on tdc I still need to rotate crank 180 which make cam make point to about 3 oclock

I should also add I've never heard the engine run that is why I tore it down. It was pulled out of a truck that someone planned on doing an ls swap with I wanted the ls and other parts for my 73 f100. So the engine I pulled apart was not the ls it was the original motor or I should say that was the motor that came out of the truck in the first place.

Also yes driver side of block is 1357 and passenger side is 2468

Please understand that the crankshaft turns twice to the camshaft revolving once, so each time you want to verify if the # 1 cylinder is on or coming up to TDC, you may need to turn the crankshaft 2 revolutions to re-align your marks and the # 1 piston at the top of the cylinder. HTH

I understand that as I said in my first post timed it 6 and 12 made crank turn 360 now cam is 12 and crank 12. I still need to turn the crank another 180 degrees to be at tdc

360 of the crank is ONE revolution, you need to turn the crank TWICE to be back where you started!

sounds like you have it correct but just don't fully understand where things are sometimes----------

In a 4 stroke / cycle engine ( conventional gas engine) the crankshaft needs to revolve twice to the camshaft revolving once to make the full cycle.
the cycle being suck/squish/bang/blow.. or in nicer terms, - intake / compression / power / exhaust .
That takes 2 revolutions not one.

Welcome to CHR:

It sounds like you installed the cam and timing gears correctly. As has been mentioned, the crank turns twice for every one revolution of the camshafts – that’s why you can have both a 6/12 o'clock and a 12/12 o'clock orientation on the timing marks on the gears.

Once you have installed the timing set, you need to install the cover and the harmonic balancer and turn the engine over until the timing mark on the balancer matched the 0 (zero) on the timing tab. Confirm that both intake and exhaust valves are closed on #1 – if not, rotate one more time. (If you can not achieve this result, you may have an incorrect balancer/timing tab combination). Adjust the valves (1/2 turn from zero lash – no more!) as follows:

INTAKE
• with #1 piston intake valve at full valve lift, adjust #6
• with #8 piston intake valve at full valve lift, adjust #5
• with #4 piston intake valve at full valve lift, adjust #7
• with #3 piston intake valve at full valve lift, adjust #2
• with #6 piston intake valve at full valve lift, adjust #1
• with #5 piston intake valve at full valve lift, adjust #8
• with #7 piston intake valve at full valve lift, adjust #4
• with #2 piston intake valve at full valve lift, adjust #3

EXHAUST
• with #1 piston exhaust valve at full valve lift, adjust #6
• with #8 piston exhaust valve at full valve lift, adjust #5
• with #4 piston exhaust valve at full valve lift, adjust #7
• with #3 piston exhaust valve at full valve lift, adjust #2
• with #6 piston exhaust valve at full valve lift, adjust #1
• with #5 piston exhaust valve at full valve lift, adjust #8
• with #7 piston exhaust valve at full valve lift, adjust #4
• with #2 piston exhaust valve at full valve lift, adjust #3

Then you can put the rest of the engine together and be assured that the engine will be ready to fire.

Stab the distributor (I’m assuming HEI) so that the rotor points to the front of the engine and begin placing spark plug wires with number one corresponding to the position of the rotor and proceed clockwise 1-8-4-3-6-5-7-2. Engine should fire and allow you to time from that point. Set initial timing at 8 degrees BTDC and you’ll be ready to go.

Good Luck – let us know how you progress
Glenn