May have screwed up installing new cam. Need help!

[JohnnyD]

Hello everyone! I decided to upgrade the cam in my 273 that I'm putting in my 63 Valiant. I'm new at doing this and, after some reading and a few videos after the fact, I realized I may have made a mistake. I'll go over what I can remember what I did because I did this almost 2 years ago and the engine has been sitting ever since.

Before opening the engine, I found top dead center of the #1 piston by watching the valves open and close.

I installed the cam gears dot to dot after putting in the new cam.

I re installed the distributor facing the #1 cylinder.

What gets me nervous is I dont remember moving the crank from tope dead center, yet the timing mark is way off. Did I do this right? Should I have set the crank to the timing mark instead of top dead center of #1? Is there a way to fix this if I have screwed anything up? Any help would be appreciated as I don't want to fire this thing up for cam break-in until I know for certain I've got this straightened out. Thanks all!

 

[1MeanA]

...Before opening the engine, I found top dead center of the #1 piston by watching the valves open and close...

That's not how you find TDC. I would do it over again. Watch a few videos like this

 

[Sterling]

Depends on your timing gear manufacturer and cam manufacturer. Which timing mark are you referring to? I think most timing gears, when installing dot to dot, crank dot at 12 o'clock and cam dot at 6 o'clock puts #6 cylinder at tdc firing. So the distributor rotor should be at #6, Vibration damper mark should be a 0 tdc.

 

[JohnnyD]

Depends on your timing gear manufacturer and cam manufacturer. Which timing mark are you referring to? I think most timing gears, when installing dot to dot, crank dot at 12 o'clock and cam dot at 6 o'clock puts #6 cylinder at tdc firing. So the distributor rotor should be at #6, Vibration damper mark should be a 0 tdc.

I was referring to the vibration damper mark. And it is not anywhere near the timing marks.

 

[73Charger318]

Hello everyone! I decided to upgrade the cam in my 273 that I'm putting in my 63 Valiant. I'm new at doing this and, after some reading and a few videos after the fact, I realized I may have made a mistake. I'll go over what I can remember what I did because I did this almost 2 years ago and the engine has been sitting ever since.

Before opening the engine, I found top dead center of the #1 piston by watching the valves open and close.

I installed the cam gears dot to dot after putting in the new cam.

I re installed the distributor facing the #1 cylinder.

What gets me nervous is I dont remember moving the crank from tope dead center, yet the timing mark is way off. Did I do this right? Should I have set the crank to the timing mark instead of top dead center of #1? Is there a way to fix this if I have screwed anything up? Any help would be appreciated as I don't want to fire this thing up for cam break-in until I know for certain I've got this straightened out. Thanks all!

Did you by chance change your damper? If so, the timing mark will be way off. I used this one on my 273 rebuild, and timing mark was 90 degrees off.

Summit Racing SUM-163273 Summit Racing™ OE-Style Harmonic Dampers | Summit Racing

Free Shipping - Summit Racing™ OE-Style Harmonic Dampers with qualifying orders of $109. Shop Harmonic Balancers at Summit Racing.

www.summitracing.com

 

[JohnnyD]

Did you by chance change your damper? If so, the timing mark will be way off. I used this one on my 273 rebuild, and timing mark was 90 degrees off.

http://[URL][URL]https://www.summitracing.com/parts/SUM-163273

[/URL][/URL]

No I used the factory damper. I don't remember moving it after the install. Could it have been off from the start?

 

[1WildRT]

first, get a tool like this..

Summit Racing SUM-900189 Summit Racing™ Piston Stops | Summit Racing

install in #1 cylinder, carefully rotate engine till the piston contacts the stop... Mark the damper at the zero pointer.... Rotate the engine backwards till it contacts the piston stop.. Now mark that location & remove the piston stop... Measure the distance between the two marks, divide by two & mark the center of the two previous marks..... Remove the stop marks to eliminate future confusion..

Now, rocker cover removed, lay you fingers on both #1 cylinder rocker arms... Without looking at the arms, just by sense of feel, rotate the engine to the point the exhaust valve just about closes & the intake just barely moves, we/re talking less than .010... That is split overlap & should occur at TDC, look at the damper , if you hit the mark your fine, if not take it apart....

 

[Murray]

If you installed the gears dot to dot (which is correct, see post #3) that is TDC for #6 cylinder and 180 degrees off for #1 cylinder. Now when you put on the balancer you are off 180 degrees. Typically you would bring up the balancer to #1 and then install the distributer to fire #1 cylinder.

 

[toolmanmike]

Depends on your timing gear manufacturer and cam manufacturer. Which timing mark are you referring to? I think most timing gears, when installing dot to dot, crank dot at 12 o'clock and cam dot at 6 o'clock puts #6 cylinder at tdc firing. So the distributor rotor should be at #6, Vibration damper mark should be a 0 tdc.

If you installed the gears dot to dot (which is correct, see post #3) that is TDC for #6 cylinder and 180 degrees off for #1 cylinder. Now when you put on the balancer you are off 180 degrees. Typically you would bring up the balancer to #1 and then install the distributer to fire #1 cylinder.

Yes and yes. Pull #1 plug and stick your finger in the hole. You can do this with a compression tester hose as well. Turn the engine over until it blows your finger out. That should be #1 TDC (or close) and your balancer should line up with the timing tab. Check your distributor rotor and it should be lining up with #1. If it is pointing towards #6, Pull it and reinstall it correctly.

 

[1WildRT]

If you installed the gears dot to dot (which is correct, see post #3) that is TDC for #6 cylinder and 180 degrees off for #1 cylinder. Now when you put on the balancer you are off 180 degrees. Typically you would bring up the balancer to #1 and then install the distributer to fire #1 cylinder.

180 camshaft degrees is 360 crankshaft degrees so the damper is in the exact same spot as if he had set the cam at TDC #1..

 

[fishmens67]

I re installed the distributor facing the #1 cylinder.

Dot to dot with cam sprocket dot at 6 o'clock and crank sprocket at 12 o'clock the engine will be firing on number 6.
12 o'clock and 12 o'clock would fire number 1.

 

[JohnnyD]

Dot to dot with cam sprocket dot at 6 o'clock and crank sprocket at 12 o'clock the engine will be firing on number 6.
12 o'clock and 12 o'clock would fire number 1.

So if I had #1 at TDC and installed dot to dot, the cam would be 180 out?

 

[fishmens67]

So if I had #1 at TDC and installed dot to dot, the cam would be 180 out?

The distributor is 180 out. Anyone that has done a cam swap has made this mistake a least once.

 

[toolmanmike]

So if I had #1 at TDC and installed dot to dot, the cam would be 180 out?

Yes but one full turn of the crank would get you to TDC on #1 and if the timing cover were off you would see the marks lined up 12:00/12"00

 

[JohnnyD]

Thanks for all the advice everyone! As there's a few things here I need to check I've formulated a plan. Let me know what yall think so I can move forward.

1. I need to verify I'm at TDC on #1 and that the timing mark on the damper is in the correct position. I'll do this by placing my thumb over the spark plug hole, turning the engine, and waiting for it to blow my thumb off. I'll then check where my mark is on the damper. It's my understanding the mark on the damper should be pointing at 0.

2. Next will be the distributor. I'll check to make sure the rotor is pointing at #1. If it's pointing at #6, I installed it 180 out.

3. I'll need to take the timing cover off and verify the dots are both pointing at the 12 o'clock position. If not, I'll need to loosen the valve train and turn the cam to the 12 o'clock position?

Am I getting this right?

 

[fishmens67]

Just pull the dang distributor and drop it in 180 from where it is now..

 

[fishmens67]

Rotate the dang engine before you pull the timing cover to TDC on the timing tab and see where the distributor is pointing, no need to pull it apart yet.

 

[JohnnyD]

Rotate the dang engine before you pull the timing cover to TDC on the timing tab and see where the distributor is pointing, no need to pull it apart yet.

Ah ok, I'll start there!

 

[JohnnyD]

OK, turned the timing mark on the damper to 0 and it's pointing to #6 on the distributor. However, I also hooked a compression tester to #1 and got no reading on it at all after 2 full turns. This doesn't seem right as it was a running engine before I installed the cam. I thought for a second maybe the rockers are loose but it should still build compression even with that.

 

[JohnnyD]

Update: Tested again with a new compression tester. Still no reading. And with the manifolds on I can't reach my hand down in there to put a finger on the hole and turn the engine. Having a buddy come over to help me in a bit. Any theories on what is going on?

 

[junkyardhero]

Update: Tested again with a new compression tester. Still no reading. And with the manifolds on I can't reach my hand down in there to put a finger on the hole and turn the engine. Having a buddy come over to help me in a bit. Any theories on what is going on?

i don't know if you're turning the motor over by hand or rolling it with the starter. if you're just doing it by hand it likely won't register on a compression tester.

if you truly don't have compression then either the gauge or the process is messed up, or you installed the cam wrong and bent some valves.

 

[crackedback]

If you've turned the engine over and don't know how many times, you need to start fresh. Stop with the 180 out, 360 out... back to basics with observable functions.

is it all together? If so, turn the engine over and WATCH the #1 intake rocker, second rocker from front on drivers bank. When it runs the open to close cycle, the timing mark coming to TDC, that is #1 firing.
No intake, same deal watching the #1 intake lifter. Up, then back down, next time mark comes to TDC, that is #1 firing.

This all assumes you are turning it over clockwise looking at the front of the engine.

Roll it back about 10-15* and set the timing to fire there, rotating the distributor to fire a timing light. Should be ok to start. Sometimes they want a bunch of timing to fire first time. Prefill carb and make sure squirters are working as well.

 

[1MeanA]

According to the OP he never properly found TDC to begin with. He needs to start over following a good procedure.

 

[RustyRatRod]

According to the OP he never properly found TDC to begin with. He needs to start over following a good procedure.

And there you have it. He should have never turned the engine over. If you don't know what you're doing, either don't mess with it or find someone who does. I mean no offense by that. Nobody knows how to do it all. We're all ignorant about different things. For example, I wouldn't do brain surgery. I wouldn't mess with micro electronics, nuclear reactors or heavy electrical work like running a new service. You gotta KNOW your limitations and DON'T go outside that box, UNTIL and UNLESS you actually LEARN about it. Again, no offense of disrespect. Lord knows I've effed up my share of things in the past and I will again, I'm sure. But VERIFYING an engine is at TDC is very important and if you were not sure, that's when you should have STOPPED.

 

[crackedback]

It's dot to dot. Where he took it apart, if he spun it over is irrelevant to crank/cam orientation. Either the dots line up or they don't. If dots lined up, it's in where it "should" be... no guarantees with parts these days! LOL Always good practice to verify.

Putting the distributor, different deal...