Timing question

Matt Conlan

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Two Harbors Minnesota
Just replaced the timing gear in my 70 Newport. Pretty sure I did everything right, but when I try to start now, it sounds like the timing is off. It'll turn over fine, and try to catch, but it sounds really slow and dies after a few cycles. I also replaced the fuel pump. Is there a way to check without engine running, or is it just trial and error?
 
Could be 180° out. Usually pops and gags on cranking up. Loosen distributor rotate rotor 180° and give it a try. Only two ways to go spot on or 180 out.
 
Check compression too, might tell you if your off

Put # 1 to tdc and see if the rotor points to #1
 
i think you guys just like trying to get new people to blow up their cars sometimes.

matt you dont say how you did your timing as far as lining everything up, but lets assume the dist is in the correct place, and the timing chain and etc. and you dont say which engine so i cant tell you what the FSM says is stock timing.

but on a big block set it to 10-12- ish BTDC and try to start it. if you can get it running and stay running, you can loosen the dist. holder bolt slightly and turn the dizzy clock/counterclockwise.
when you do that, how the motor is running should change. when you do this you are advancing/retarding the timing.

the guys are saying take out the dizzy, spin the rotor 180, and stab it back in. but i dont think you should do that yet.

tell us more about what you are working with, and what you think the timing is now.


try not to die -

- saylor
 
Hey, thanks for the response! Ive set timing before, so I know the sounds (I think). Its a 2bbl 383. I Lined up the sprockets when I replaced the timing gear, and the distributor was at TDC when I pulled the old gear off. Got it all back together, and it won't start. It's got spark and fuel. I guess the question is how do I set it to BTDC if I can't get it running? The manual (and the sticker on the fender wall) says 2 1/2 BTDC. This is probably easy, but I can't figure it out.
 
Next question, did the timing marks on the old chain show that it had jumped? Looking at the pics, the cam gear looked intact, so I'm not believing that was the problem.
 
No, the distributor wasn't out when I changed the timing gear. Its been wiggled around since. The marks on the sprockets looked like they matched up, but I guess it could've moved a tooth or two. That pic is from right when I took the cover off.
 
No, the distributor wasn't out when I changed the timing gear. Its been wiggled around since. The marks on the sprockets looked like they matched up, but I guess it could've moved a tooth or two. That pic is from right when I took the cover off.

OK, so IGNORE the advice about turning the distributor 180 degrees.

Hindsight is always 20/20, so we can't go back and check if the chain had slipped. Let's ask this... Did you have to move the cam any to get the marks to align?
 
Yes. The new chain was much tighter than the one I took off. Btw, thanks so much for the help. I love the cars, but am purely a backyard mechanic. Only know what Ive had to fix.
 
OK, turn the engine over until the TDC mark is at zero. Take the distributor cap off and turn the distributor until the rotor is pointed at #1 and lock it down. That will get your timing close enough.

Next, because the engine is turning over slow (could be a lot of reasons), check the voltage of the battery and be sure it's at full charge. Basically, eliminate the easy, dumb stuff that can trip you up.

Look into the carb and pump the carb linkage a time or two and see if there's gas in the float bowl. It does take a little to get gas flowing through the new pump, so again, let's cross that off.

Now, if you have gas, and you have enough battery to turn the engine over, give it another try.
 
To ensure the engine is at TDC, you'll need to also remove the lh valve cover to ensure that both #1 valves are closed. The other way is to remove #1 spark plug and rotate the crank (manually or with the starter) to see when the #1 cyl is on its compression stroke (i.e., TDC).

From my one experience with timing chain replacement, so far, it's VERY important to make sure the dots are exactly "one over the other one" as they can appear that way, but not be really that way. A straight-edge or tight string can help ensure the dots align with the centerlines of the cam and crank, vertrically.

Hope you get it all figured out. Please keep us posted,
CBODY67
 
Turn it a little bit clockwise try to start. Repeat till it runs properly. Move it back and forth till it idles smooth with vacuum advance disconnected. Pay no attention to the emission idle and timing tag, they had to appease the government, you want it to run good. Find a sweet spot and as long as your initial does not go over 13/14 degrees leave it, and enjoy.
 
Just to be clear. And I’m sorry for not being clear myself. When we are all saying turn the rotor 180° - you have to loosen the hold down or remove it enough to pop up the distributor just enough to pull up the shaft to disengage the from drive (tip looks like a screwdriver) gear and then you can spin the rotor like a top. Sorry I assumed that if you replaced the timing gear. You were on number one TDC etc etc. Sorry my bad.

Every now and again I get lazy about TDC or BDC and install the distributor’s rotor (not the housing) 180 out. Housing ( vacuum advance pod) should always be clocked at about the same position. You are 100% right to think I’m an idiot for telling you to spin the housing to where it can’t physically fit. Sorry again for the cornfusion .
 
Success! No apologies necessary. Its what it was. I refound TDC on #1 piston, and it lined up perfectly with the timing mark. The rotor, however didn't hit the #1 plug. I rotated the engine by hand one turn, the rotor lined up, and it fired right up.
 
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