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Discussion Starter · #1 ·
Ok I have a 351w original engine. Just uprgraded to a a 4bbl Edelbrock Carb. Last night I set the timing to 10 advance, what Chiltons said. I messed around with the vacuum lines a bit and it seemed to idle and run good. Took her out on a drive ran it hard in 3rd and 4th seemed to be pinging bad so I backed off and went home. WHen I got home and cut her off it dieseled a LONG time like a full 10 seconds then shook a bit and let out this long hisssss. After that it will not start at alll just turns over and over....Any ideas of what could be going on. No fluids leaking...It has coolant...If i had the vacuum lines hooked up wrong could I have screwed something up bad???
HELP
 

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does'nt sound like a blown engine.maybe the timing is off.try changing the timing and see if it wont start.good luck!
 

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Sounds like it ran backwards and jumped a tooth or two on the timing chain. If this is what happened, then you may also have bent a valve or two. If you have not changed the timing after this last run, then rotate the crank by hand to 10 BTDC and see if your distributor is still pointing at (or very near) number one on the cap. If not, then it jumped timing. You'll have to replace the timing chain. You should also run a leak down test and see if any of the valves are bent.

To avoid this in the future, (assuming you don't have any vacuum leaks) use a better grade of gasoline and before you shut it off, put the trans in first gear, let off of the clutch just enough to put a light load on the motor. Then shut it down. This will keep the car from dieseling.

Good Luck,
 

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Agreed, timing chain failed during overstress during dieseling. Not a huge issue. Get a double roller timing chain when replacing. You will not spend a whole lot more but you will never revisit this area :)
good luck
jer
 

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Hi,
Not 100% sure but I am about 98% sure that the stock Windsor motor can free-wheel. This means that the design of the engine is such that the open valves never intrude into the space used during the motion of the pistons.

Hence if the timing chain went off and the cam stopped spinning while the bottom end rolled forward (or backward) causing some of the valves to be open when they should have been closed, the valves sitting in an improper postition would not have collided with the piston(s).

In Short - you will not have any bent valves. If I am wrong I aplogize in advance and will accept whatever flaming is mandated by law. :)

take care
jer
 

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Dieseling is generally an indication that the timing is advanced too far. So is an engine that labors to crank over when starting. Do the old finger in the #1 hole test to find TDC and see if your distributor rotor and timeing marks are in the right vicinity. Double check your setting, you may not have gotten the lock down tight enough and the distributor may have moved on you. Never overlook the obvious.
 

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Discussion Starter · #9 ·
so will it hurt anything to adjust the timing and see if it starts and runs..or should I replace the timing chain before i do anything else???
 

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Check everything out first!

Jim's point is excellent, the dizzy could have moved if not tightened and the timing could just be off. Verify TDC on the balancer on the compression stroke of cyl#1 to the rotor pointing to #1 of the dizzy cap.

If the chain is broken, the motor will spin very very freely and sound different than normal when cranking. Also the dizzy rotor will not spin while craking the motor.

If the timing is just off, the motor may fight itself while cranking and be hard to turn over.

If the chain slipped, #1 on the dizzy will be in rather a new location compared to where it was pre-failure. you will be able to detect that I think....
jer
 

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Discussion Starter · #11 ·
Sorry for the lack of knowledge but you guys are great...Could anyone elaborate on the "old finger in #1 hole test"?
Also jer siad "the dizzy could have moved if not tightened and the timing could just be off. Verify TDC on the balancer on the compression stroke of cyl#1 to the rotor pointing to #1 of the dizzy cap. " How can I do this..just rotate the balancer to TDC and then open the dizzy and see if the rotor is pointing at #1????
please clarify if I am lost...lastly so you are saying the whole distributor and all that I rotated to set the timing could have moved?? b/c all that is still in the same place.
THANKS A TON..I at least feel better....
 

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Sounds to me like u just need to retard the timming and try to start.. When u drive with the timming too advanced the engine over heats and will cause the deiseling after the ignition is turned off.. Though it is possible for the timming chain to have skipped, I'd think the timming is wrong since that is something u just did.. Check human error.. then look at the mechanical.

AJ
 

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Discussion Starter · #13 ·
It tried to start the first time I tried which is also the first time today but didnt....so then, ok I retarded the timing and it still wont start..tried a couple of positions and nothing just continues to turn over and over. I checked and the dizzy rotor is moving when I try and crank it so am i correct in assuming that the timing chain is ok, or could it still be the chain?
 

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By that I meant that you should remove the number 1 spark plug (front one on the passenger side). Bump over the starter until air is pushed past your finger. This is the beginning of the compression stroke on the cylinder. When the air starts to escape, the timing mark should be pretty close to the TDC mark on the balancer. Bump it a little closer to line up the timing mark with TDC. When this happens, the distributor rotor should be positioned just before the #1 terminal in the cap. If the relative position of all of this stuff is in line, the timing chain is probably ok. Verify spark. Hook your timing light to the #1 wire and crank the engine and you should get an impulse to trigger the light. If not, you have no spark and are chasing the wrong rabbit! Good luck and keep us posted.
 
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