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Old Gal Not Started Yet - Part 2

Started by racertb, May 27, 2014, 01:39:33 PM

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racertb

I thought I would continue the saga with the latest on this new thread.  So after much trial and error, I pulled off the valve cover so I could view the cam gear teeth through the rectangular window.  I had my son turn the crank slowly several times so I could get a good look through the angle I had.  From what I could see, there was no sign of teeth missing or even being chipped on the fibre gear...I really doesn't look and feel like fibre anyway.

I also had a chance to see the valves operating, but I want to go back and make sure that the valves for each cylinder are in the "proper" position.  I am attaching a few photos for reference.

These two are just shots of my view of the cam gear teeth looking through the "window":






This shot of the valves with number 1 piston (on right) aligned to TDC:




This shot is of number piston #3 and 4 valves (#4 on left):






I know this probably doesn't help to solve the issue, but again, I want to make sure the valves are operating the way they are supposed to.  Is there anything else I should be looking for at this point?  I don't want to have to get into to engine/timing cover if I don't have to...

Thanks for your help...

Ted




Old Man

It is fibre. Take a magnet ,one of those 'collapsing radio antenna like' ones for retrieving errant parts, and see if it sticks to the gear. I think you'll find it won't. They were all red fibre with teeth cut into the gear by some machine. They were not formed in a die. Anyways I can't tell if the valves are being pushed up at this moment or not. I would have to be there and watch the lifters movement to see when they are closed or open because you can't see the camshaft. So it appears the engine is in mechanical time but I don't see why it hasn't caught and run. I've been thinking about your problem and I really believe these engines will at least run when spark and fuel are within +/-20% of factory spec. It might run "ugly" but it would run. This engine should not be this ticklish. Sorry I'm running out of things to give you. I think we're going to have to start over and take it step by step.     

racertb

Thanks Old Man, the advice you and others give is at least encouraging even if I can't get her started yet!   I will get my son to turn the crank for me, or I could push the starter button, so I can watch the valve movement.  At first glance yesterday, they were all moving and looked like everything was working OK, at least mechanically.  I want to watch again myself.

Again, the gear looked good as far as I could see from the backside.  If the valve operation looks good, I guess I'll put the valve cover back on and go back to seeing if it's electrical.

chetbrz

I agree with the old man.  These engines will run with a lot out of spec.  When this problem first occurred you were encountering backfiring through the carb and the exhaust.  This to me indicates some major event.  You have verified compression, spark, and gas so all that can be wrong now is these are not coming together at the right time. 

I have found over the years when a good technician is looking at the same things for more then 2 days the problem is someplace else, otherwise they would have found it.  You must be missing something in your troubleshooting process or your timing method.

I know this doesn't help much but you need to do something different.  Take a different approach think back to when this first occurred and approach it differently.

Chet...
http://www.1948Plymouth.info           Web Master - Forum Administrator - AACA member

imoore

Ive been following this for a while and i have a feeling the ignition is not timed right.
If you can wait until sat i will pull my valve cover of and make a video on how to set timing. Using the valves to identify TDC on cyl 1
I relay want to read a post on success she runs. 
Ian
1928 Q tourer (Holden bodied)
Several vintage stationary engine

racertb

Thanks Ian!  I appreciate the offer to go out of your way for this.  I will be out of town for several days and won't be able to get to the car for a week, so no rush.

I have a couple of video clips of the car turning over and also me rotating the distributor by hand.  If I can post them, I will.  I want to make sure the distributor looks "right" (to you all following this post) as I'm rotating it and that it doesn't have too much play/slop.

Ted

frankp

http://www.dodgebrosclub-australasia.asn.au/docs/vacuum_timing_db4.pdf

Ted, realize this won't be of any use until you get your engine running, but...

Sorry I don't have further ideas for you to try.  frank
frank p

chetbrz

Ted,

I am sure you have considered all this but I think it would be easy to mix up.   If you are using cyl 4 to find TDC on cylinder 1 than you need to determine tdc of cylinder 4 after ignition on the exhaust stroke.   Just at the point the exhaust valve closes for cyl 4 will you be at or near TDC for cyl 1.  The intake valve will open right after the exhaust valve for cyl 4 when cyl 1 leaves TDC.

You might just be 180 out with your timing.   Just something to check.  I can write the word 'you' instead of the word 'your' and read it over and over again and never see the mistake.  Just the way our human brains work, or at least my screwed up brain.

I hope this helps you.., we all would like to hear that you are back on the road.

Chet...
http://www.1948Plymouth.info           Web Master - Forum Administrator - AACA member

racertb

I will check anything at this point, but I was using the "finger" method on #1 cylinder to feel the pressure of the compression stroke each time I did this, so I believe I was doing it correctly.  Then #4 should be on the exhaust stroke.  That's why I want to look at the valve positioning with the valve cover off to see if there is an issue there.

I've been out of town for several days, so I hope to get back at it this coming weekend.

chetbrz

#9
Ted,

If you watch the valves for cyl 4.  When the exhaust valve is open the pistons are driving upward.  Cyl 4 is driving to exhaust and cyl 1 is getting to the firing position and is in the compression stroke. 

When cyl 4 exhaust valve closes you are roughly at TDC for both Cyl 4 exhaust stroke and cyl 1 TDC compression stroke.   If you continue turning the crank cyl 4 intake valve will open while cyl 1 is in the power stroke driving down after the plug has fired. 

When cyl 4's exhaust valve closes just before cyl 4's intake valve opens you are at TDC on cyl 1 or just a couple of degrees before TDC cyl 1.   PS... At this point the rotor should be under the distributor caps # 1 plug wire and the points should have just opened.

I hope this helps,  Chet...
http://www.1948Plymouth.info           Web Master - Forum Administrator - AACA member

racertb

Thanks Chet.  This valve positioning you describe is what I want to look at before I put the valve cover back on.  I am hoping that this will get me closer to getting her started again.