The site has been very helpful but it seems that the further i get nto the set up on my truck the more strange it becomes...At this point I have checked TDC on #1 it is good. I checked the distributor alignment at TDC..I is at #1...The engine does fire but when i try to check the timming mark it is about the 12 oclock position on the dampner...???? i try to lower the idle and i can not get it to hit the tab. I retard the dist. and then the closer to o i get the worse it runs...I have an HEI MDS dis, running edellbrock RPM cam and 750cfm carb, vith accu drive gears...Am I missing somthing??? Any help would be apperciated... Thanks
You may have a damper that has spun and the timing mark has shifted. Is this a new build? The timing mark might not be proper for the damper. Try timing it with a vacuum guage rather than a timing light.
The damper might bee off a newer 350 with the timing mark at 12 O'clock. I would try a different damper.
disconnect the vacuum advance and plug the hose,then set the timing with your light.make sure to get the idle at around 600 to 800 rpms first.slowly turn the distributor and see if the mark moves as you turn it.also chevy had different timing tab locations on the timing covers,you might have a different cover especially if it is aftermarket.another thing is later chevys had a second line on the balancer for using a magnetic timing device. if you dont have a vacuum advance then your marks are not right on the balancer.
If your camshaft is stock hook a vacuum gauge to your intake and adjust to your highest vacuum and you are good, If it has performance camshaft run your engine up to about 2500 rpm (this is where most street cams draw a steady vacuum) adjust until you reach your highest vacuum and you are good.
Have you actually verified that TDC is correct you need to use a piston stop and make sure it is correct before you do anything else, once you do that you will know exactly whats wrong and won't have to speculate. You have to have TDC correct or you will never know how much actual timing you have in it and could very easily damage you engine
Just a thought but , maybe it's time to buy a stick-on timing tape for the balancer when you are positive that you are at TDC of the compression stroke. Distributor and rotor position to #1. And at this point use an old fashion non digital timing light that doesn't have all the fancy stuff. Sometimes your high dollar timing light can screw things up. Just my thoughts but sometimes it's the little things that kill........ruggs
yes damper is not new...i pulled it from a 350. is there a visual way to tell the difference..or how do i determine if the damper has spun? getting ready to just start over by checking timing gears to TDC. But hope to rule out the small stuff first...
To check the damper mark....Pull the valve cover on #1. Turn the engine over to split overlap, with exhaust closing and intake opening. When they are even, that's very close to TDC. If the timing marks are on 0, you're OK. If not, something has moved, or you have the wrong damper. MSD sometimes needs different timing. We had it on a 2.8 Chev V6, and the dist. had to be turned at least 20 degrees from stock position.
Had this same issue on an old 283. As Nitro said, get a piston stop, turn engine by hand[wrench on dampner bolt] one way, mark where it stops, turn the other way until it stops, mark that. Split the difference and thats TDC. Now, put a timing tape on your dampner[make sure its for the right diameter, usually 8 inches but measure it] aligning your mark to TDC on tape. Disconnect vac advance and have at it.
Thanks soo much for all the advise..i am going to put it to use this weekend..i will let you know how it turns out...
Well this is the results and i would like some more input....I got the pistion stop tool and used it to find TDC on #1 pistion.. worked great..looks like the dampner mark is off about 2 1/2 inches... so with the new marks at TDC #1 i looked at the distributer...It was 180 off #1 so i repositioned it to #1...NOW The engine is back fireing and popping and pinging.... SO i placed the distributer back 180 degrees and am left in the same position.Engine runs and timming mark is off... So i think this may mean that the cam is 180 off..Am i correct?
Just a helpful hint here,,,,,if you are lining up your timing marks(dots) on cam sprockets/gears,this is NOT number 1 TDC Firing---its # 6 TDC Firing. In other words,if you are lining up the dots,not rotating the engine,re-***embling,and installing distributor with the rotor pointed at # 1 on the cap,it wont run. Let us know & good luck man,you'll get it!
small chevys had three different damper pulley that had the timing marks at different positions from the keyway. the late dampers 84 and up timing mark was 30 degrees right from keyway early was right above at 2 degrees and mid was 10or15 somewhere like that cant remember . make sure your timing tab matches your damper! <!-- / message -->
You must have the dist. close to being right,,,,it won't run if it is 180 out. Have you considered trying to time the engine by ear? Advance the timing a little at a time until it drags starting when warm,,then ,,back it down a couple degrees,,,that will be in the ball park. I have never heard of a dampener ring slipping 2 1/2 out of position,,it must be the wrong one. Do you have any pics of the dampener? Tommy
One other thing, if you have #1 at TDC you won't see any timing marks at all, #1 has already fired and the distr is now on its way to #8
#1 piston will be at TDC every time the crank turns. Remember that it is a four stroke four cycle engine and has Intake, compression, power and exhaust strokes. When you did the thing with the piston stop, did you put a mark on the damper exactly half way between the two marks for stopped forward and back? That would be the tdc mark you use with your timing light. That is if you marked the other two marks where 0 on the tab was when you rotated the crank one way and then the other. Now that you have the 0 =tdc marked on the damper you need to make sure that #1 is up on compression and not up on exhaust. either by removing the valve cover and watching the intake valve rocker open and close while the mark comes around or by putting your finger in the plug hole and having someone bump the engine over with the starter while you wait for the compression to blow against your finger and watch for the mark. It will take several tries most likely but you should be able to get #1 up on compression on tdc that way. Now make sure that the rotor in your distributor is pointing toward #1 on the cap and tighten the distributor down. You do have the firing order correct and the wires in the cap in the right direction? Now put #1 plug back in and fire the engine up.
well been playing with it all after noon..found TDC #1 on compression stoke..Used piston stop and marked dampner both ways....then found the center of that and ****oned up the dist. cap...rotor was close to #1/// fired it up, warmmed it up, then slowly advanced the dist. found the sweet spot...runs excellent...new timming mark is about 20 degrees advance by my best guessament...gona get a timiing tape to put on the dampner so i can get an more exact timming perspective...so i can work on the next phase... thanks for all you help...but i know i will be back...
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