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cubed
05-28-2009, 03:09 PM
xxx
TS1955
05-28-2009, 03:58 PM
That is correct. You align them up when putting the engine together, it makes it easier. But like you said, when it's on compression stroke on #1 cyl. both dots, crank & cam will be on top.
TS1955
cubed
05-28-2009, 04:41 PM
cccc
cepx111
05-28-2009, 10:31 PM
hi guys, when my chevy small block is on tdc on comp. stroke is the dot on the cam sprocket at the top? thanks.
NO, that is NOT correct.
The cam sprocket DOT should be at the bottom or 6 o'clock position and the crank sprocket DOT will be at the 12 O'clock position.
It;s reccomended to degree it in per the cam card, but dot to dot will get you pretty close.
TS1955
05-29-2009, 01:25 AM
Cepx, when you initially put in a cam you will align the marks up, BUT when you rotate the engine to "compression" stroke on #1 cylinder both dots will be at 12 o'clock.
TS1955
johnracer
05-29-2009, 02:20 AM
Cepx, when you initially put in a cam you will align the marks up, BUT when you rotate the engine to "compression" stroke on #1 cylinder both dots will be at 12 o'clock.
TS1955
Yep, that's correct......
topsportsman1
05-29-2009, 02:42 AM
hi guys, when my chevy small block is on tdc on comp. stroke is the dot on the cam sprocket at the top? thanks.
NO, that is NOT correct.
The cam sprocket DOT should be at the bottom or 6 o'clock position and the crank sprocket DOT will be at the 12 O'clock position.It;s reccomended to degree it in per the cam card, but dot to dot will get you pretty close.
Charles that position would be #6 TDC firing
oldandtired
05-29-2009, 06:49 AM
There are two TDC for each rotation of the camshaft. This may be what is confusing.
One TDC is compression, the other TDC is the overlap between exhaust closing and intake opening.
Always easier to install chain when the dots are close together.
desoto30
05-29-2009, 07:30 AM
I've wondered for ages why it's been done that way,one would think that the dots would be close when #1 is @ tdc compression.This position (6 tdc comp) also puts the fuel pump lobe on the heel IIRC.
cubed
05-29-2009, 08:44 AM
cv
TS1955
05-29-2009, 10:11 AM
What do you mean by "quick do it yourself" valve job? Did you just lap them in with compound or what?
TS1955
cubed
05-29-2009, 10:33 AM
cc
TS1955
05-29-2009, 01:11 PM
That's not the best way to do a valve job, but as long as they hold compression it won't keep it from starting. What's all done to the engine. Give us some more info. If you have spark, compression, timing, & fuel it should run.
TS1955
bowhay
05-29-2009, 08:52 PM
is it popping threw the carb or out of the exhaust?
cepx111
05-29-2009, 10:12 PM
Cepx, when you initially put in a cam you will align the marks up, BUT when you rotate the engine to "compression" stroke on #1 cylinder both dots will be at 12 o'clock.
TS1955
Ohhhh, Ok, :shock: after you have the cam in Gezzz, didnt catch that one...lol I feel like a idiot.
Open mouth - insert foot.
Dam it, first mistake I made all day, or yesterday :roll:
cubed
05-30-2009, 02:45 AM
is it popping threw the carb or out of the exhaust?exhaust
bowhay
05-30-2009, 03:16 PM
set ur motor at tdc and restab ur distibutor pointing at number 1
ur timing is way off
suicidebomb
05-31-2009, 04:49 AM
It doesn't matter which post on the distributor cap the rotor is pointing at. As long as you wire it starting with no. 1 from there, and wire the firing order from there it does not matter. If you can turn the dissy, far enough to get timing set properly, it does not matter which post on the cap you start with. You do not need to pull your dissy back out. Put your motor at TDC on the compression stroke, pull the cap off your dit. and see where it's pointed, and wire the ignition from there.
cubed
05-31-2009, 06:04 AM
is it popping threw the carb or out of the exhaust?exhaust
TS1955
06-01-2009, 08:03 AM
Do you have a solid lifter cam?
TS1955
cubed
06-03-2009, 03:37 PM
Do you have a solid lifter cam?
TS1955yes,560 solid lifters
zipper06
06-03-2009, 08:35 PM
What no one has addressed here is that a lot of the new roller chains have 3 different keys on the crank sprocket. They come with Sq. key notch, an triangler notch, and a circular notch. It depends on which notch you have installed the gear on the crank shaft. That is the notch that must line up with the top gear, otherwise you could be off a ton on the timming of the cam. Basically when everything is right the harmonic balancer should be at 2:00 on "0" with top dead ctr. of the engine/number 1 piston.
Zip.
dparker
06-04-2009, 04:33 AM
X2 zip, some even have 6 to 8 slots in the crank gear. While your installing the timing gear now is the time to degree the cam. I've seen them as much as 6 degrees off.
dparker
06-04-2009, 04:41 AM
I went back and read that its already running you did a hand lap on the valves. If you got any of the valves mixed up from the seats they were initially in you won't be able to lap them in. I would do a leak down on your engine. And if you didn't get the timing chain lined up correctly you may have a few bent valves. I don't think your valves are seating making you have no compression.