Timing Marks.

Gentlemen, need some help. Have a 65 327 Chevy that is running poorly. Thought the balancer ring had slipped, changing the timing mark position. Pulled the balancer, pulled the timing cover, checked the timing chain (O.K.), brought the no. 1 piston up to TDC (visually), the timing mark is at least 30* advanced with the piston @ TDC, firing. The chain is good, with the cam timing marks lined up (dot to dot) I can not remember if the ignition marks should line up.

Also, shouldn't the vacuum advance be on the p***enger side when the distributer is installed correctly? I inherited this situation and it has been a LONG time since I worked on something like this. Any and all help will be appreciated.

John

 

You might want to pull the dizzy and re-install it with No 1. cylinder ATDC on the compression stroke and the rotor pointing to No 1. plug wire post.. And yes, the vacuum advance swings out on the p***enger side.. Timing is 6 er 8 degrees BTDC...

 

Looks like you're right, the balancer's spun. If piston is at TDC, the timing mark should be also. Yes, vacuum advance should be on the p***. side of the car.

 

You might just have the wrong balancer. Some engines had the timing pointer in a different place, with a corresponding change in the marks. 30 degrees is about how far the wrong one would be out.
The position of the vacuum pot doesn't affect how the engine runs, but it may limit the amount of adjustment available, and make the connections hard to get to. There's a reason the General put 'em in that way!

 

Thanks guys, I think I'm going in the right direction (not the engine). The pointer appears to be an accessory item that bolts on to drivers side using two of the timing cover bolts with the pointer positioned at approx. 1 o'clock (drivers side). The cam cover is an accessory aluminum piece. And again, when no.1 piston is brought up to TDC firing, the timing mark is on the p***enger side at approx. 10 o'clock. Funny thing is that the engine started beautifully, ran well, but didn't have the balls the owner thought it should. The engine is in a 21 Dodge roadster with 327, camel hump heads, 7201 Edelbrock cam, street tunnel ram, dual 500 cfm Edelbrock carbs, MSD ignition, TH 350, and 3:70s out back. Should move smartly, right? Well it does, but the owner feels something has been left on the table. Trying to get it to perform better.

Again, thanks for the input, and any additional thoughts would be appreciated.

John

 

If you can verify that it is at TDC with a piston stop, and you have the wrong pointer, as there are a few different ones for sbc, you can mark the damper to work with the pointer.

With the stop in you rotate the engine forward and back and mark the damper each time and the middle is TDC.

Also with the vac off you can check the timing with a vac guage, rotate to highest vacucm and back off 2 '', that should get you real close,

 

If your outter ring has spun ... I'd be searching out a new balancer. Bet that ring could do some damage if it came off at highway speed.

 

Yea the vac cannister goes on the p*** side but it really doesn't care all it shows is that whoever was building it didn't know any better.

If you have the wrong balancer for the crank shaft the timming marks will not be correct. Avbout 30 degrees off is what you end up with as I recall.

If youre chain is tight you shouldn't have anything to worry about in there. I don't recall any of them that ever jumped time that would run.

It could be that the engine is just ****. Have you run a compression check on it?

 

PnB, yes we did take a compression test and the cylinders were 155 lbs. straight across, give or take 5 lbs. Just spoke to the owner and he related that the previous owner had problems with the balancer (as in a loose ring) and had the outer ring re-bonded. Can you feel where this one is going?

 

If you trust the rebonding job (***uming they are telling you the truth) then just find TDC on #1 and using whatever timing tab you have ... cut a thin slot in the balancer (hacksaw blade?) to mark where TDC is according to the timing tab.

 

John
I'm thinking that you should probably hunt down a balancer they don't get pricey until you get into SFI rated stuff.

If you have a miss it might not hurt to delve into the dizzy at least that's what I would do. Loose or bent shaft, worn cam if its a points dizzy or bad condensor or points. You know general tun up stuff.

If its an electronic dizzy I might suspect either the control mod or the pickup coil.

Just things to think about.

 

X2 borntoloze. Check vac advance unit with vac pump and check vacuum with car running.

 

X2. Years ago, a good friend of mine blew up a balancer on a 350 in a chevelle street-racing. It REALLY did some damage, pieces even went through the frame rail. Right on the starting line too, scared the sh*t out of us.

 

easy way to check the ring. take a machinest squaire with a center head. put it on the ring line the blade up so it goes through the center of the keyway and the bolt hole that holds the pulley on. the timing mark should be in line also. if not replace it.

 

Went over to Jim's house today and verified that the dampener ring had moved using bob308's suggestion. Worked perfectly! The ring had moved (or was installed improperly from the last rebuild). Anyway, Jim was doing his due diligence on the internet and found the Dampner Docter, so he's going to call them in the morning and see what they have and how much. Found 1/8 in. play on the slack side of the timing chain so he wants to replace that. Will reposition the dizzy at the appropriate time (towards the end of the rebuild) And all seems to be going well.

Again, thanks to all for the timely and accurate help. Will get back to y'all with results.

John