Degreeing cams

This is the method I use.

 

All,

A good friend loaned me some parts. I have a set up for the TDC and the degree wheel. The weather has been excessive here especially for CA so I did not get much done. Here are some pics of the degree wheel and my flywheel at PM1-4. I have not done anything yet just put them on to see how they fit.

Several people said I should put some oil in my cylinders since I have not started the car in 16 months, what would any of you suggest??? Also can anyone suggest a good assembly lube???

Thanks to all who are helping,

Rob
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Sweet

 

Rob,
On my recent year long adventure servicing my F355 I used Redline Assembly lube. Good product.
I also added a small amount of good old Mystery Oil to each cylinder to keep everything lubed.

 

All,

I am hoping to have all of your attention and that you will all be inclined to give me some more useful advice, which I am in desperate need of.

I kicked down and bought a TDC tool from Dan at Ricambi and would like some pointers on how you would or are using it. My cams are all out I am thinking about moving the crank about 5mm in either direction marking the degree wheel then finding the center point as my TDC. Is there a better way?

My good friend Peter lent me his set up which allows a dial gauge to be on both the intake and exhaust at the same time. I am think of using #1 cylinder for the rear bank and #5 for the front bank. However my #5 front bank intake can was the one that was reground down a little and wanted your advice on if I should use a different cylinder for this measurement. Am I correct to assume that Cylinder 1,4,5,& 8 are all at TDC at the same time?

I got some Redline assembly lube. I was wondering while I have the cams out, I will blow them out with air. I want to make sure all the oil holes are clean, maybe put a toothpick in each one.

Am I correct to assume that I need .5mm clearance on the heel of the lobe I am going to check, before i proceed?

Here are some pics of what I have assembled and the degree wheel. I attached a small finishing nail to hang down to help me be as accurate as possible. The wheel slips on the dampener and has 3 set screws to tighten it to the dampener. I think this was one of Kermits early designs.

Once again I appreciate all replies, and want to do this correctly. I love this car like a child, and want to have it be as well set up as the original designer intended...

Rob
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Please read back to previous posts in this thread that refer to a piston stop or dial indicator. I use the piston stop in the spark plug hole. Here is how I find top dead center.....Insert a threaded piston stop into the #1 spark plug. Adjust the depth of the piston stop so that the crank stops close to TDC. Turn the engine by hand until it contacts the stop in the spark plug hole. Put the degree wheel to zero on the pointer. Turn the crank around the other way until it contacts the stop in the spark plug hole again. Note the degree number. Divide number of degrees that the crank is short of making a complete revolution by two. Remove the piston stop. Turn the crank to the point half way between the two degree points. Move your degree wheel back to zero under the pointer. Compare actual measured TDC to the timing mark on your flywheel, harmonic balancer etc.

 

Please don't stick a toothpick in there. If you must, some thin steel wire maybe, with a circular wound top to put your finger into. It would be frightening to loose something down the hole.

 

Uncle ray,

I read the post over several times but even the OP was using the dial indicator with the cams in. Since I have the cams out and my new $500 TDC tool I was wondering if there was a different procedure. I know there was talk about not rotating CCW as this takes slack off the belts but since I have no belts on I thought there might be a simper way?

 

Rob,

You're over thinking this process. In that you've got TDC estimated by the factory pointer, turn the engine x degrees BTDC at note the exact reading on the dial indicator. Now turn the engine in the direction of rotation towards ATDC until the same reading is achieved on the on the dial indicator. If your degree wheel indicated the same angle both BTDC and after TDC, your pointer is correct.If not, split the difference between the two readings and rotate the degree wheel accordingly. Repeat until both the dial indicator reading and the angle BTDC and ATDC are identical.

David

 

No. Cylinders #1 and #4 are at TDC at the same time when the PM1-4 mark on the flywheel is aligned with the reference mark on the fixed plate. Likewise, cylinders #5 and #8 are at TDC at the same time when the PM5-8 mark on the flywheel is aligned with the reference mark on the fixed plate. (And I know that you already know that!)

 

Statement of the obvious just to be clear:
all cams removed....................ok to turn crank - valves are closed
belts removed, cams in place... NOT ok to turn crank - some valves are open

Rgds,
Vincenzo

PS: Does the F-car dryer work any faster ;-)

 

Correct...and correct.

 

My engine has been sitting 16 months should I squirt som type of lube down in each cylinder?

Thanks for everyones replies going out to work right now!

 

Try an internet search on "cylinder fogging" -- should get you some links to products like this:

http://www.lubes-n-filters.com/synthetics/fogging-oil.html

Although they are really formulated to be used before the storage period, after 16 months of disuse, I'd lean towards doing some fogging (either with something like that product, or just regular motor oil if you can find a way to "spray" just a small amount in evenly - you need to be careful to not use too much and hydrolock) before cranking (and no matter what I used, I'd turn the engine over by hand a few times before cranking to ensure that wasn't hydrolocked), but JMO...

 

All,

Steve that looks cool, but says to spray into carb while engine is running. I wonder if I should just get some and spray into each cylinder or put some oil in each hole......

Anyway here is what I did today.

I went out all excited to use my new TDC tool. I took out the plug #1 and put the tool in. I was not sure how far too put the dial indicator in the the tube but ended up putting almost all the way in, before tightening up the set screw. I tried to follow David's advice but think I got the translation wrong. I spent about half the day rocking the engine back and forth over TDC each way about .2mm and ended up with readings that were inconsistent.

I called my brother in law who is a dragster engine builder and he told me what I was doing was wrong. here are his instruction please tell me what you think. I am starting to understand what he was telling me.

1. First I had my plugs in he told me to take them out.
2. He said roll engine over CW a full revolution go past TDC and stop at 10 degrees BTDC
3. Set dial indicator at zero.
4. Roll engine back about 350 degrees CCW and watch my dial indicator as it came to TDC then stop at 0 on indicator at same setting I had made previously.
5. Check my degree wheel and should be at 10 degrees ATDC.
6. Adjust degree wheel by half the difference if needed.
7. Repeat until I got consistent number on either side of TDC.
7. Lock down degree wheel, this is my actual TDC

Here is where I am having problems and not sure what I am doing. First I think I was using too small a measurement. He tried to explain to me why about 30 minutes and I think we were confusing each other with our terminology. He said that because of the load on the bearings and going back over the top would not achieve accurate results. He said the measurements had to be made as the piston is rising in the cylinder. After about an hour of following his procedure and finally got it to zero out my dial indicator at 10 degrees BTDC & ATDC. I then rotated the engine with the piston still going CCW until I got to TDC on the degree wheel and stopped. I went over to the flywheel mark and it was pretty close to spot on. It was getting late and I will try to repeat it again tomorrow when I have more light.

I have a few questions.

1. Since the engine rotates CW isn't BTDC on the right side of TDC on the wheel.
2. His procedure seems allot like some of the procedures early in this thread with a piston stop. Do you think it is an accurate way to measure or should I modify it.

He also said I was stupid to get the more expensive tool and I was using the dial indicator essentially the same as a piston stop if I was smart enough to read it. Which is fair enough. I am a very visual guy being an ex musician, and since I played drums never very good in anything above basic math (well maybe I would have been good if I studied instead of playing drums), however once I am shown something or see it. I seem to get it pretty easy. This process seems overly complicated but rolling the engine back and forth 350 degrees seems simple. What am I not getting???

Rob
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WD-40 is excellent for such purpose.

 

I didn't say to necessarily use that particular product -- I suggested that YOU do some research on such products to see if one might be appropriate for your situation (i.e., YOUR homework, not mine ).

With regard to the method, your B-I-L was giving you good advice (and using a piston stop or a dial indicator is mathematically identical if the method is correct). It has to do with making sure that the frictional force between the piston and the cylinder is working in the same direction for each measurement and puts the slop in the moving bits in compression (to reduce hysterisis); however, I'd say that your wording is a little off, and would be more accurate as:

1.
2. ...roll engine over CW almost a full revolution (~350 degrees) past TDC and stop at 10 degrees BTDC -- but only turn the crank CW -- do not overshoot and then come back CCW a little.
3. Set dial indicator at zero.
4. Roll engine back about 340 degrees CCW and watch the dial indicator while approaching TDC and stop when the dial indicator again reads 0. Again, this must be done in a smooth, continuous fashion -- i.e., by only turning the crankshaft CCW -- do not overshoot and then recorrect CW a little.
5. Check my degree wheel and should be at 10 degrees ATDC.
6. Adjust degree wheel by half the difference if needed.
7. Repeat until I got consistent number on either side of TDC.
8. Lock down degree wheel, this is my actual TDC

With regard to: "1. Since the engine rotates CW isn't BTDC on the right side of TDC on the wheel."

Yes, your photo of the degree wheel with the pointer on "10" is at 10 deg BTDC for a 308 (whose crankshaft rotates CW in normal operation as viewed at the snout end) if the degree wheel is mounted to the crank snout end.

 

Thanks Steve, and all for your suggestions.

The first thing I did was hit google and it appears motorcyclist put a few drops of engine oil in the cylinders before and after winter shutdowns and crank it around a bit. Since we have V8's would the oil get spread to the tops of the pistons. I am worried WD-40 might strip the oil off. I use this as one of my #1 cleaning solvents?

I did just as you said Steve and will try to replicate the procedure tomorrow to double check. I hope the TDC is where I think it is right on my flywheel mark as this will greatly simplify my markings for timing.

Thanks again for all for putting up with me, this procedure is stretching my abilities, and I thank you all for helping.
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Freinds,

Sorry to hijack the thread but maybe someone will learn from my stupidity.

I spent the better part of the day trying to find TDC. I assume there must be some play in my bearings as I could only get within a couple of a hundreds of a MM. The degree wheel i have is pretty tight and even though I adjusted it at least 10-15 times I still kept coming up a little off. I put a few drops of oil down each cylinder and that made everything smoother.
I am pretty satisfied as i got the wheel to within half a thickness of the marks on the wheel and I am assuming this will be OK? When I kept rotating CW after my last reading my degree wheel at 0 TDC is perfectly inline with my flywheel mark. I was looking for perfection but I guess this will have to do. If anyone has any suggestions I can keep trying I think 2 full days trying to find TDC is enough!

I took my cams apart cleaned and started reassembling them. It was tough getting the pulleys off and on, and the pins extracted, I expect it will be harder on the engine. I am hoping for a good result and hope that the next part goes smoother.

Thanks for all your help and suggestions.

Rob

 

Robert

Perfection does not exist, not even as a state of mind.

 

I thought of something. If you make an adjustment to one pulley doesn't it mess up the pulley alignment next to it on the belt?? Then do you have to adjust that pulley also???

 

If your cams are out -

Consider using a threaded piston stop that meets your piston half way between TDC and BDC. At this location, the crank moves the piston the greatest linear amount for the minimum degrees of rotation. At this location, you will get more consistant readings.

The crank stop will remove the play at the bearings as you rotate CW and CCW.

Then use the 'split the difference' method as others have already described.

You may find it easier to bend a piece of wire around to match the degree wheel's location rather than vice versa. Make sure your technique is not introducing parallax errors into the measurement (eyeball in the same location each time your read the marks).

This should get you exactly on TDC.

Rgds,
Vincenzo

 

No (in theory ). Think of the drive sprocket, the belt, and the other cam sprocket as being fixed in space. When you make the pin adjustment, you are moving the cam relative to the cam sprocket of interest, and the pattern of the teeth on the cam sprocket of interest also remains fixed in space (because the belt is fixed in space); however, you might need to move the cam sprocket of interest by an integer # of tooth pitches relative to the (fixed) belt in order to get the result you want. I know that your head is already swimming , but the adjustment involves selecting the right pin and hole combination between the cam sprocket and the cam AND selecting the right belt tooth-to-cam sprocket combination to get the 1 deg resolution in the adjustment per the attached file.
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I am still working on this procedure, with breaks for work, weather & parts. I am intrigued by this method but FBB one paragraph explanation is confusing me.

1. What is the definition of maximum lobe lift.

2. I am not a mathematician so what would be the calculation for my 308 with early cams.

3. My car was running great why am I doing this?? No need to answer this one....

BTW I bought a piston stop to check to see how that aligns with the info I got with the dial indicator set-up

Thanks for everyone putting up with me, I am not as dumb as it seems, well maybe! I want my car on the road before it rusts.....

Rob
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Sweet