Timing Chain/Lifters on a 73 Eldo

[aggie2012]

After reading several postings about the timing chain going bad Cadillac 500's, I have been kind of paranoid about driving my 73 very far. I looked today, and found out when I turn the engine by hand, the distributor has about 4 degrees of timing delay. Also, when running, there is a ticking sound like I have a bad lifter. I have added things like marvel mystery oil and transmission fluid to the crankcase to try to correct it, but it continues to tick. If I decide to pull the engine to replace the timing chain, would it fix the ticking if i replace the lifters?

The engine doesn't smoke, so I know my valve seals should be okay. Or is there something I'm missing?

[The Tassie Devil(le)]

4 degrees of play doesn't seem much as there will be a bit of play due to chain stretch andgear wear, and it is very hard to measure the amount of degrees of "slackness" whilst the engine is in the car.   Did you measure this at the crankshaft before the distributor turned, after winding the engine backwards to take up the backwards slack?

Firstly, how many miles has the engine done?

Before doing anything major, I would be attaching a mechanical Oil Pressure Gauge to the back if the block and seeing what the Oil Pressure is.

Then I would be pulling the Distributor, and with a torch (Flashlight), carefully look down the Distributor Hole, and with a long screw driver, see how much you can "waggle" the timing chain and also see if there are any nylon teeth caps missing from the Cam Gear.

With the nylon missing, the chain will flop all over the place, and be easily visible to the naked eye that it is loose.

The ticking noise could very well be a bad lifter, and changing that could easily result in a replacement camshaft, as a worn can lifter bottom could mean a worn cam lobe.

Bruce.

PS.   I have pulled the engine out of an Eldorado on its' own, and with the Transmission and Diff, and the last method is by far the easiest.   Especially if you have a leaking rear trans cover you want to fix

[TJ Hopland]

The Cadillac's don't seem to smoke like Chev's do when the seals are no longer doing their job.  Not sure why, maybe its because Cadillac had better quality guides and valves so they did not wear as bad?

4 degrees does not seem excessive to me either, I think if the plastic was all gone there would be more.

If you plan to keep the car for a while and it appears its all original you might as well just plan on pulling the engine at some point.  Even if the chain is not the big problem there are other issues like all the seals getting a little weepy and freeze plugs that could be considering falling out.  Get it out and in a stand.  Pull the covers and intake and have a good look at things.  You can get a pretty good idea what kind of shape things are in and if its original.  You can see the cam in enough places to get an idea what shape its in.  If its all looking good and fairly clean a new gasket set, plugs, and a timing set and you should be good for a long time and you will know its all looking good.   If there are issues you can take it down further.   If you have what you think is a valve train noise then pulling the rockers and lifters would not be a bad idea.  You may find a badly worn rocker arm or a bent push rod.  You can replace the lifters without replacing the cam.

Like Bruce I have done just engine and done engine with trans and I too prefer to do em together.  Like he said it seems like the trans could always use a bit of attention too.   The chain cover and shift shaft seals are things that can't be done in the car.   Also gives you a chance to do a nice clean up on the engine compartment.     

[Viator Trudeau]

I replaced the chain set on my '68 Eldo apx. 5,000 miles ago W/ 90k miles.  The nylon tooth covering was gone and the teeth were sharp and the chain was riding high on the teeth because of a smaller P.D.  I used a "L" shaped wire to see if any teeth were near the drain and found a few.??  The chain and crank sprocket were like new.  there was 7 degrees of slop in the chain due to the worn cam gear, but engine ran well, but needed the new set, was lucky.
On the '74 W/ 75K  have not looked for the slop yet, but looking in oil pan with the wire I found no teeth?? just the usual sludge in the oil pan of an oils engine.   Previous post indicate plastic sucked into the oil pump screen.  Is the oil pick up near the dear of the pan?

[The Tassie Devil(le)]

The Oil Pump Pickup is virtually touching the bottom of the pan.

All the pieces came out of the pickup screen in my '72, and the oil pressure was still remarkably at 40 Psi.

Bruce.

[Viator Trudeau]

Bruce,  In your three pictures,  My '68 cam gear was the same as yours W/ the sharp teeth.  The last picture W/ the pick up showing, and the one W/ the pile of teeth pieces, did all of the pieces get sucked up in to the bottom of the pick up.  Is the pick up screen flush W/ the bottom of the pick up.  The prospective and size of the pick up does not seem to hold all of the gear pieces?? Were some scattered in the bottom of the pan. What was the large piece in the lower fore ground of the picture?


Where in the pan is the pick up in relation to the space between the drain and rear of pan?
My '68 oil pressure at idle was 45 PSI ,good I thought, all things considered.  Your extra thoughts on this subject would be welcomed.   Thanks.
V. Trudeau  #8697

[aggie2012]

I didn't get really fancy with testing this. All I did was pull the distributor cap off and turn the fan both directions. There seemed to be very little delay in the rotor turning so I will assume it's okay. When the weather gets better, and I have more money I want to put lifters in it to get rid of that annoying ticking and the exhaust leak it has.

The clock on the dash says 18,000, but I'm sure its turned over.

I have the manual but I'm going to ask anyway: In a nutshell, how do you pull the engine and trans together? I'm assuming just pull the half shafts off the axles and take the mounts loose?

Also, where can you get a camshaft that won't cost you an arm and a leg?

[bcroe]

I replaced the chain set on my '68 Eldo apx. 5,000 miles ago W/ 90k miles.  The nylon tooth covering was gone and the teeth were sharp and the chain was riding high on the teeth because of a smaller P.D.  I used a "L" shaped wire to see if any teeth were near the drain and found a few.??  The chain and crank sprocket were like new.  there was 7 degrees of slop in the chain due to the worn cam gear 

So with all the plastic gone, 7 degrees of slop?  Fine, I have been saying, 6 degrees means change
that timing set NOW.  I can't imagine driving the car in that condition.  Bruce Roe

[Doc Hubler]

This was virtually the same issue with the 425 engine on my 1967 Toronado.  The engine really seemed to run ok, but now it will run much better, especially now that I'm replacing all the vacuum tubing (complete restoration of the car).  All the nylon that was left was on the oil pick up tube, and look exactly like the stuff in the picture.  The gear teeth were not as badly worn down as the one in the pictures above, but you need to change it.  Nobody goes with those nylon geared teeth anymore.  I think my car was running on borrowed time.  Common for those cars of this era.  Run em till they stop.

[The Tassie Devil(le)]

Bruce,  In your three pictures,  My '68 cam gear was the same as yours W/ the sharp teeth.  The last picture W/ the pick up showing, and the one W/ the pile of teeth pieces, did all of the pieces get sucked up in to the bottom of the pick up.  Is the pick up screen flush W/ the bottom of the pick up.  The prospective and size of the pick up does not seem to hold all of the gear pieces?? Were some scattered in the bottom of the pan. What was the large piece in the lower fore ground of the picture?     Where in the pan is the pick up in relation to the space between the drain and rear of pan?
My '68 oil pressure at idle was 45 PSI ,good I thought, all things considered.  Your extra thoughts on this subject would be welcomed.   Thanks.  V. Trudeau  #8697   

The "lump" is a congealed piece made up from some pieces of nylon that was being held together by the oil.   I didn't make any attempt to clean them up.

Everything was jambed up within the confines of the oil pickup screen.   I couldn't believe it when bits kept on coming out.   The stuff was jambed in there pretty tight.   And the pickup is like 1/4" to 5/16" from the bottom.

Next time I drain the sump, to replace the running-in oil, I will have a look up the hole and observe.   But, I will wait till all the oil has dripped out, so I don't get an eyeful.

Lastly, my odometer read 86,000 miles, and from the condition of the pedals, it looked like to might have been original miles, but after stripping it down last year for the total rebuild, the broken rings, bore wear and Head/Valves condition, I would say it was at least on its' second time around, or even third, as the speedo cable had been broken between the trans and the Cruise Module.   But it still drove beautifully, and got reasonable Fuel Consumption.

Bruce.

[aggie2012]

I thought I would update everyone on how my engine dissection is going. As I figured, but horribly underestimated, my timing chain was shot. I couldn't believe it had that much play and the engine was still running. I also found two really soft lifters. Either way, for less that $200 I bought all the gaskets, timing set, and lifters.

The only problem(s) I ran in to were broken bolts. The studs on my passenger side exhaust manifold both broke after two days of soaking with PB Blaster. My only option was to take the entire manifold off and have it machined. As luck would have it, I broke off 5 out of 8 bolts in the head. Now I'm sitting here looking at half an engine waiting on a phone call. Oh well...it'll be worth it.

The only question right now I have for the cadillac gods is what kid of bolt do ya'll recommend to screw into the front of the crank to get the damper/pulley assembly back on?

[The Tassie Devil(le)]

Firstly, you have removed the engine?

[aggie2012]

Maybe I should have started there lol. Yes, I pulled the engine and transmission in one big chunk. With as little clearance as there is in front of the engine, it made no sense to separate them.

[The Tassie Devil(le)]

Good, as this is the best way to go, as doing the broken bolt repairs would mean pulling the head/s to do this task..

The easiest way to reinstall the front hub is to use a long, fully threaded 9/16NF bolt, and thread a nut up the thread towards the head, and install some heavy duty washers to take up the difference between the nut diameter and the hole in the hub.

Put the hub on and then thread the bolt into the crankshaft snout, and then with one large spanner, hold the bolt head still, and with another large spanner, wind the nut down to act as a press to push the hub on.

Don't forget to lubricate the nut and washers to lessen the friction, and also, don't forget to put the slinger before putting the front cover back on.

Now, with the Exhaust Manifold Bolts that have broken, simply drill the threads out, and if you have a set of left-handed drills, and a reversible drill, once you get to the nearly correct size, the last one could grab the bolt deep down, and actually wind it out of the hole.   This lessens the chance of damaging the thread in the head.

I have found that when using ezi-outs in a seized thread, one generally breaks the ezi-out, and this makes life even harder.

When toy put in the new bolts, use a substance called "Neverseize", or similar, so this doesn't happen again.

As far as the Cam goes, did you replace that?   With the "soft" lifters, I would nearly guarantee that the lobes of the cam are worn, and will soon damage the replacement lifters.

Bruce.

[aggie2012]

So putting the hub on is basically like putting a power steering pulley on?

I just took it all off and gave it to an old machinist I know. Everyone said he's the best.

How do I determine if the cam is bad? All the lobes looked uniform, and there were no rough spots or pitting on it.

[The Tassie Devil(le)]

Yes, but a lot tougher.

I take it that you pulled the Cam to inspect it?

Can you post a picture of the damage to the Lifters?

Bruce.

[aggie2012]

Yes it is out right now. I'll take pictures of everything tomorrow and get it posted.

[TJ Hopland]

Didn't your pulley puller set also have installer stuff too?    Mine did  I will have to look at what brand it is.  Someone gave it to me a long time ago, I will have to look it at the brand name. 

How does your cam look?  Pretty rare to pull a GM cam from that era that had some miles on it and not see some wear and pitting in some areas. 

How about rockers?  The Cad's I have pulled apart always seem to have one or two that have some pretty good wear on em, not sure why, maybe they got a little crud in the pushrod early in their lives and didn't get as much oil as the rest. 

[aggie2012]

Here are the pictures of my lifters. I inspected the cam a little closer and found that I have a lobe that's about .40 lower than the one next to it. I guess I'm getting a new cam now. Where is the best place to get one for the lowest price. My $200 project has close to doubled in the past 48 hours.

My rockers looked pretty decent, but again, I haven't inspected them that closely yet.

[aggie2012]

Here's another pic