Situation:
* Used stock cam with about 79,300 miles on it, in the engine, untouched from the factory (or rebuilder)
* Hydraulic lifters
* Engine in vehicle
* Engine has been working, running acceptably (to a layperson [me])
* Only replacing timing set due to high mileage and needing to deal with suspected chain cover oil leak

Goal Summary
I want to do the best job i can degreeing in the existing used cam with the new timing set, with as little disassembly to this working engine, in the van, as possible.

Research
I’ve spent days studying existing posts here on Slantsix.org, plus done some outside reading. All a great help, but i still have a few questions and want you experts to check my planned workflow (below).

History
I am the second owner of this van, as of 5 May 1989. Notes from first owner:
New engine @ 55,056 miles, 8 June 1987. New manifold, fuel pump, motor mounts, shocks.
59,555 miles: new fan, new water pump.

No information on the new engine. Tell-tale evidence and much conjecture suggests a new or rebuilt factory engine, possibly installed by a family member with a connection to a Dodge dealership. This was the seller’s mother’s car, and nothing i’ve ever found on it as-purchased suggests any performance tweaks. Point being: odds are extremely high that this is a stock build with a stock cam.

Jan. 2009, (1)26195 miles: verified vibration damper timing mark with degree wheel and piston stop: exactly correct. Currently (1)34361 miles—8166 miles driven since verification—and front of vibration damper looks like this: A couple of professional shops plus biennial emissions inspection stations have since then needed to verify timing, never finding/reporting to me any issues with instability nor improper timing marks.

Thoughts on whether this existing damper is OK? Do i need one (another one or this one rebuilt) from Damper Dudes? It’s the 2 pulley groove style.

Tools and Skills
* Have a degree wheel and piston stop, and know how to use those.
* Have 1", 2 1/2", and 3" long end of crankshaft bolts, with one flat washer and one lockwasher, with a matching 1/2" drive socket & wrench.
* Have the replacement crankshaft seal (several, actually) for the presumed source of the oil leak, and timing chain cover gasket. Still have some Ultra Black for additional sealing on the oil pan edge.

– Do not have a vibration damper puller. Irish Dave* has one, which i’m likely to borrow.
– Do not have and have never used a dial indicator. Unsure whether Irish Dave has one or not.
– Have never been deeper into any engine than having valve covers off, and vacuuming out junk under a carb opening in the intake manifold. Any deeper work than that is daunting to me.

* Irish Dave is a new acquaintance around my age, which is to say around the age of the original Slant 6 engine release. He has familiarity with these engines, though likely not the depth of expertise of many experts on this site (but i don’t truly know). Don’t think he’s a member here, but if he is, Hi Dave (waves), and thanks!


Workflow from current stage of disassembly, pictured: 1) Pull vibration damper with puller
Take a careful look at the shank of the vibration damper and see if there's a groove worn in it which might require a repair sleeve. Are repair sleeves readily available at my local auto parts store, or where?

2) Inspect source(s) of oil leak

3) Remove timing chain cover. If there’s a hole in it, figure out how to deal with that (replace? Get someone to weld the hole closed? High temp. epoxy? I don’t know. Suggestions/advice?). Else clean, remove existing crankshaft seal (screwdriver and hammer, being careful not to distort cover), install new crankshaft seal (block of wood and dead blow hammer, again being careful not to distort cover)

4) Somehow mark existing timing? Any point degreeing the existing setup before changing anything, to know the baseline?

5) Check timing chain stretch, for giggles?

6) Remove camshaft gear with chain. Remove crankshaft gear.

7) Clean surfaces

8 ) Install new crankshaft gear

9) Install new camshaft gear and chain, lining up the dots

10) Degree cam

Valve Timing, from factory service manual:
Intake opens (BTC) 6°
Intake closes (ATC) 42°
Exhaust opens (BTC) 36°
Exhaust closes (ATC) 12°
Valve overlap 18°
Intake valve duration 228°
Exhaust valve duration 228°

Took me days of reading and thinking and reviewing Stockel’s Auto Mechanics Fundamentals (thanks again to Dan for the advice to get that book years ago) to get it through my head that:

6° intake opens before TDC + 180° + 42° intake closes after BTC = 228° intake valve duration.

I still don’t understand the definitions of ATC and BTC, nor how ATC and BTC may or may not relate to TDC and/or BDC, and online acronym lookups aren’t helping.

So then 228° ÷ 2 = 114° for peak of the intake cam, so 114° - 6° = 108° ATDC on the intake stroke for intake lobe center. Is this correct?

I’ve read over and over for a disassembled (or at least out of the vehicle) engine with solid lifters how a dial indicator is placed on the lifter end or rocker arm or somewhere, and about the 1.5 but not literally rocker arm ratio, but have no idea how this applies—if it does—to an assembled in-vehicle hydraulic lifter engine.

How does a person measure valve lift on an assembled, working hydraulic lifter engine installed in a vehicle? Or is some other procedure used to degree in a cam in this situation, in a working engine when replacing a timing chain set due to stretch/wear?

Anything else i need to know/think about/keep in mind as i strive to find and fix the oil leak, replace the timing chain set, and put everything back together and again have a reliably working, running, and hopefully leak-free or low-leak van?

Stuck and stumped in Pasadena, California,

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1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.

Since you mentioned the engine has been replaced, don't assume the camshaft is the factory Slant cam, unless you can verify with 100% certainly it is. Otherwise, the specs you found will be meaningless. You have chosen probably the hardest vehicles to perform this on, coupled with having never degreed a cam before is going to present numerous challenges. So, if you're still wanting to attempt this, know in advance you will get frustrated at times both from the cramped space your working in and trying to figure out what the correct procedure and order of steps are needed.

There are some specialty tools, or at least specific to the task that are required. Since you asked about lifters, often when degreeing a hydraulic camshaft, a solid flat tappet lifter is used so it wont collapse and give varying readings. A good magnetic base dial indicator is helpful along with a piston stop to first determine true TDC. Some method of turning the engine over by hand is needed, such as a socket made to fit over the crank snout. You'll need to fashion a pointer and attach it to the front of the block to mark readings on your degree wheel. As for the abbreviations you asked about, ATC, BTC are also often called ATDC and BTDC respectively, which means After Top Dead Center and Before Top Dead Center, which refers to the #1 pistons position in the cylinder, usually followed by a specified number of degrees to reference it.

It's not terribly hard, but it can be confusing your first time, especially if you watch bad YouTube videos by people that are not thoroughly knowledgeable about this subject. Be careful, they may know all the lingo, but lack and omit some info that can be important. So choose wisely....asking questions here is also a good option.

_________________
There's no such thing as too much cam....only not enough engine!

Thanks for your questions. Looks like you are trying to be very thorough, which is great. I will pick a few to answer out of your long list, and can contribute more later...

Damper: I would use that one, based on basic visual inspection. The later ones rarely slip. Get a TDC piston stop tool (or make one) and make sure it is marked correctly and has not slipped.

Cam degreeing: If it is anything like a stock cam, I recommend degreeing it at 104 deg (intake centerline). That will work well with pretty much any mild/medium cam and you do not need to look anything up. You can measure lobe lift with the dial indicator, once that is set up, and then multiply by 1.5 to get the valve lift.

I agree with CNCdude about using a solid lifter to do your degreeing and measure lobe lift. They are $5 online or maybe at your local parts store. As he says, try to borrow or buy a crank socket so you can turn it over easily.

That's a start, anyway!

Happy wrenching...

Lou

_________________
Home of Slant6-powered fun machines since 1988

Thank you and CNC-Dude for your responses!
Excellent—one fewer thing to have to replace!

As i originally posted, i have a piston stop and degree wheel, and back in 2009 verified the vibration damper timing mark. Only 8166 mostly steady-speed freeway miles since then, so i’m inclined to consider it still accurate unless an expert here vigorously disagrees.
I’ve never had rocker arms, pushrods, nor lifters/tappets out of any engine in my life. Based upon searching and reading other posts here plus reviewing the factory service manual i gather it goes like this:

1) Remove valve cover, gasket
2) Remove rocker arm assembly
3) Remove the #1 pushrod
4) Using a special tool i don’t have and would rather not buy, remove the #1 hydraulic lifter/tappet
5) Insert solid lifter
6) Reinsert pushrod

Might this be good enough for manually rotating the engine for degreeing the cam? Is there any reason the rocker arm assembly needs to be reinstalled here? I’m envisioning the dial indicator on the top end of the pushrod, and i’m turning the engine by hand doing all the cam lift vs. degrees turned measurements.

Is there a reasonable way to get lifters out without using a special tool? I’m pretty patient, and so much time has flown by on this project, a little more won’t kill me. But i really do need to get this van back on the road—it’s my only motor vehicle!

In terms of turning the engine, when i did it last time (2009) i threaded a bolt into what i thought was the end of the crankshaft and used a 1/2" drive socket wrench. Read about the trick of removing the spark plugs to make turning easier. Are the threads in the vibration damper and not the end of the crankshaft?

Appreciate all the help from everyone here.

_________________
1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.

They are in the crankshaft. If it had no bolt in it for 30 years the threads are probably pretty junked up and rusted...etc. Clean it as best you can and use plenty of lubricant on the bolt threads. I usually use a small impact and never seize. Run impact in until it starts to get tight and run it out. Keep running it back and forth until you get the threads cleaned out. Bolt is 3/4" fine thread I think? Good luck.

Rick

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Thanks Rick. As noted in my original long post, i have 1", 2 1/2", and 3" long end of crankshaft bolts, with one flat washer and one lockwasher, with a matching 1/2" drive socket & wrench, which i used in 2009 when verifying the timing marks on the vibration damper, related to replacement of the distributor gear which i was doing at the time. Pleasantly, back then the threads were fairly clean to begin with. I don’t remember having any problem whatsoever running the bolts in and out.

Also, back then, the timing mark was spot-on: no adjustment/re-marking needed. To me 8166 miles since then seems low enough mileage that i can trust the marks, esp. since every 2 years there’s the biennial emissions testing where they have to verify timing. This past January the tech reported it was spot on when i asked him.

I hand-threaded in one of the bolts a few weeks ago, and it still went in fine.

Having not yet had the vibration damper off and having not looked carefully/thought things through deeply, i wasn’t sure which piece has the threads, which you answered—thanks! It makes sense that it would be in the crankshaft.

*****
Still hoping to read anyone’s thoughts on what i need to do to degree in the cam in a reasonable yet hopefully easy manner. Last night i was reviewing the factory service manual, which had an intriguing timing verification procedure. I quote it here verbatim:
Thoughts on that procedure:

1) I like the idea of inserting a spacer rather than messing with pulling out a hydraulic lifter and substituting a solid one solely for purposes of accurate measurement whilst degreeing the cam, but the Caution suggests that a spacer wouldn’t be applicable for the degreeing procedure as that requires far more rotation of the crankshaft. Correct?

2) My reading of Chrysler’s procedure is that #6 is starting the intake stroke, therefore #1 which is being measured would be on the power stroke. With everything else i’ve read talking about measuring #1 on the intake stroke, i’m confused about what Chrysler had in mind.

3) 12° BTDC to TDC is quite the acceptable range! Guess that’s the limit for functional operation, rather than optimal operation.

_________________
1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.

Yes, it does require more rotations of the crankshaft. When the dots on the timing set are dot to dot, the #1 cylinder is not on the power stroke, #6 is, and people often make the mistake of assuming because the dots are aligned, that #1 is on the power stroke and install their distributor based on that. Only to discover they are out of time 180°. Since your apparently leaving the head on, that is going to greatly complicate matters, especially trying to establish "true TDC", which helps to use a piston stop to perform. You may end up having to modify an old spark plug by breaking the porcelain out of it and threading the inside of the plug body for a long length bolt to reach down to the piston. I've done it, but it is far from as accurate as a piston stop that bolts to the deck of the block. As for the lifter swap, your results are only going to be as accurate as your are. You can easily be several degrees off by not locating your "true TDC" accurately, and a few more degrees off by having your hydraulic lifter collapse and give you varying readings. And that will lead you making a wrong determination of what your camshaft readings are based on compounding errors that you've made. So yes, degreeing a cam sounds fun and exciting the first time you do it, but unless you are willing to be extremely precise with the process, it really wont give you much information that can be meaningful otherwise.

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There's no such thing as too much cam....only not enough engine!

I never even thought about the "problem" of the hydraulic lifters. They are not fun to get out of the bore and replace with a solid and then back again with the peanut head! And doing it in a Van is even going to be worse. Good luck

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Any reason this piston stop i have is lacking?: Worked great in 2009.

_________________
1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.

That piston stop is fine.

I have always used the intake centerline method for setting my cams. If that method is used you are only looking for peak lift on the intake valve. So would it matter if the hydraulic lifter was left in? I don't know, and am just asking. It may not be ideal, but even if the lifter bleeds down a little on the next revolution rotating the engine, the highest lift should still be at the same reading degree on the wheel.

Correct or totally wrong?

_________________
2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

Yes, that will be fine. You really haven't mentioned what tools you have for this task, so I'm basing a lot of my comments on the assumption you are starting from scratch.

_________________
There's no such thing as too much cam....only not enough engine!

Thank you again, but… i listed everything i have and don’t have in my first post. Do i need to put up pics of what i have?

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1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.

I went back and looked at the post. It got pretty lengthy so it must have gotten lost in all that somehow.

_________________
There's no such thing as too much cam....only not enough engine!

OK, revised answer...

I would just leave the hyd lifter in there and use the pushrod (or better yet a solid lifter pushrod since it has a cup on top instead of a ball) as your "spacer" to measure centerline. The spring on your dial indicator is so weak that the lifter should not bleed down or compress at all when measuring. I have a pile of good used solid lifter pushrods if you need one, or from a parts store or online they are only $5 or so.

Lou

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Home of Slant6-powered fun machines since 1988

Excellent!

What i’m seeing in the pics for the hydraulic lifter pushrod is that even though it has a ball on top, there is an oil hole. Wouldn’t the tip of the dial indicator be stable on/in that? Or maybe i could temporarily put something in the oil hole, like a very small piece of cup-shaped plastic?

I’ve never looked at the actual ends of the existing lifters, nor have i yet used nor even held in my hand a dial indicator, so these assumptions i’m making may be misguided. Hence i seek confirmation.

Also, i gather that the one rocker needs to come off? Maybe that means the whole rocker arm assembly? I’d hoped that maybe i could put the dial indicator on top of the rocker arm on the side where the pushrod pushes, and that might be good enough (and would require that much less assembly). Or is it then an issue of all the pressure of the rocker arm and valve pushing against the hydraulic lifter?

Thanks!

_________________
1981 B-150 short Van, stock 225, California emissions package, Electronic Spark Advance (digital Lean Burn), Non-feedback Holley 1945, AT
Driven for economy, not for speed.