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Engine Disassembly - what to number?
#11
It's not about the hydraulic portion of the lifter nor the outside of it that contacts the block. It is all about the face of the lifter that contacts the camshaft. Each lifter will have a wear pattern that matches the camshaft lobe it rides against. You cannot even move lifters from one lobe to another without taking a chance on destroying the camshaft lobes.

The face of the used lifter is no longer completely smooth nor completely flat.

It is hard enough to keep from wiping out the lobes on a new camshaft during break-in when using new lifters, using old lifters on a new camshaft almost guarantees loosing lobes during break-in. Make sure you use a good break-in oil.

When the lobes fail the metal particles go everywhere. Camshaft bearings, pistons and cylinder walls, rod and main bearings, crankshaft, and oil pump are all damaged.



“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
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#12
(09-24-2018, 01:34 AM)GeoBW Wrote:
(09-23-2018, 09:37 AM)Carolina_Mountain_Mustangs Wrote: If the engine has miles on it put new rockers, push rods, lifters and cam in. Not worth the trouble if worn out. Check the rocker fulcrums for wear on the radius surface and where the rocker tip hits the valve. If worn get new.
I have never seen a Ford engine that the connecting rods and main caps were not numbered from the factory. Sure NOS rods that have never been in an engine will not be stamped but factory assembled engines are stamped. Cast in the main caps. There is a correct way to rotate the rods so that the oil gets squirted onto the wrist pins also.
If you are doing a valve job does not matter where the valves came from.
If you are going to use everything again a piece of cardboard with some holes for push rods works fine. Place the rockers in a box marked front for each side. You never never use old parts on new parts. Sure if one push rod bent or one lifter bad you change the one. Never put new lifters on old cam or old lifters on new cam.

Hi David, that's very helpful. I will look for the stamping. 

Just one point, I am going to put in a new cam, why can't I use the existing hydraulic lifters, given they have worn into the block (and I did number them)? I would have thought any wear on the cam face would be taken up by the hydraulics?
Like Don stated it is not wearing the diameter of the lifter into the hole in the block. If you look down the lifter hole you will see that the cam lob is not in the center of the lifter hole. This makes the lifters and push rods rotate during operation of the engine.
Every time I hear someone with their engine idled way down with a cam not stock I think what an idiot. Racing cams do not last long at best. Due to extreme profiles, radical lifts and heavy spring pressures eat the cam and lifters up. Do not expect a cam that is not stock to last very long. Some think it is cool to let the engine lope but it destroys it.
Just the cost of a full gasket set today is crazy. If you pull an engine apart best to do a complete rebuild or you will be visiting it again soon. If you go with a radical cam, heavy valve springs expect much earlier failure than if stock.
About the most important thing on an engine block is the clearance between the lifters and the bores in the block. For some reason the factory usually went big not small on the tolerance. You loose lots of oil around those 32 lifter bores that can starve the bearings. Sometimes the bores have to have a sleeve added to close the clearance back to original specs.
It is not cheap to do a great rebuild and finding a shop you can trust on the machine work is also not easy in some areas. It is not rocket science but you do have to pay attention to details.


When a man is in the woods and talks and no women are there is he still wrong??
Tongue
David
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#13
Here's my opinion.

1) get a "how to rebuild" book on the 351C. The questions you're asking, especially the comment about marking top and bottom of the lifters, leads me to believe that you've never been inside one.

2) The only thing that truly needs to be numbered are the rods. Most likely, they already are. 351C main caps are numbered and have directional arrows from the factory.

3) Everything else is going in the trash if it's an original engine with any real mileage. No sense in trying to save a couple hundred with worn parts.

351C-2V engines have aluminum fulcrums and will most likely need to be replaced. Valves were originally two-piece welded units and are prone to dropping a head, destroying the engine, so those need to go. Rockers get worn by the valve and will need to be replaced. Rod and main bearings need to be replaced. Pushrods get worn and may need to be custom length depending upon cam used.


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#14
Thanks David, as always it comes down to one's purpose with the car. This will be the 8th car in my garage and as such will be lucky to do 2,000 miles a year. I'm building it to be my ultimate restomoded muscle car. It's actually about the theatre of the car and the sound in particular. My mate who owns a performance exhaust shop explained to me that to get the ultimate V8 burble it's about the cam as much as headers and exhaust. I'm not building it for speed or handling - I have other cars that do these things in a targeted way.

So back to my question, why can't you use the old lifters with a new cam? They seem pretty bullet proof and have worn in? How often do they fail? Sorry about the Whys? I sound like a four-year-old, but it's how my mind works.

Cheers
George

Leave death a burnt out castle
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#15
(09-24-2018, 03:28 PM)Hemikiller Wrote: Here's my opinion.

1) get a "how to rebuild" book on the 351C. The questions you're asking, especially the comment about marking top and bottom of the lifters, leads me to believe that you've never been inside one.

2) The only thing that truly needs to be numbered are the rods. Most likely, they already are. 351C main caps are numbered and have directional arrows from the factory.

3) Everything else is going in the trash if it's an original engine with any real mileage. No sense in trying to save a couple hundred with worn parts.

351C-2V engines have aluminum fulcrums and will most likely need to be replaced. Valves were originally two-piece welded units and are prone to dropping a head, destroying the engine, so those need to go. Rockers get worn by the valve and will need to be replaced. Rod and main bearings need to be replaced. Pushrods get worn and may need to be custom length depending upon cam used.

Thanks Hemi, actually I have three manuals including the factory shop multi-volumes, but they're a bit light on the 'Why?' too. They talk about inspecting for wear and deciding to replace. From what we can see, now we're further down the track (heads and sump removed last weekend) the wear is minimal and the engine does appear to have only done 26,000 i.e. we can't see any parts worthy of replacement based on wear.

Good point on the valves being two-piece, will replace with singles.

You're quite right about me never being in a 351C before. Having now removed the lifters I can see they only go one way up. Pulled several engines, all older, apart before, but never the same one twice! Adds to the novelty detracts from the knowhow!!

Cheers
George

Leave death a burnt out castle
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#16
GeoBW,
Your comment " They seem pretty bullet proof and worn in" is correct, but what you're not understanding, is that the cam and lifters don't wear in to the block, rather they wear into each other, and once broken in, are now a team. You cannot use a new cam with old lifters, or use an old cam with new lifters. Many a fool has tried to disprove this by doing so only to spend more money replacing it all down the line. Oh, It'll run, but the components will wear each other out after not too long.Don't even consider it!
When one "breaks-in " a new engine, it is customary to start it as quickly as possible, and bring the RPM up to 2000-2500 and set it there for maybe 20-30 minutes. At this time checks are made for any leaks of coolant , fuel, and oil. What your engine is really doing at this time is mating-in the cam and lifter surfaces together, and the RPM is a speed chosen by Automotive engineers where the rods, and crank is throwing the highest volume of oil at the cam and lifters, ( lubricating the cam and lifters ) while not revving too high...…..your rings today, are made of superior design, as compared to the old days, and will break-in very quickly, sometimes in minutes, especially when a Moly-faced top ring is used. So....to recap....break-in is primarily for the camshaft and lifters. The exception is when using a roller tappet cam, break-in is non-existent.
Ever think about Drag Racing engines and their break-in? For the most part, they're ready to rev right off the stand, most racers are using a roller grind, ( no break-in ), and have rod, main, piston to wall, and ring clearances, etc, opened up as assembled, and will safely rev from the get-go without break-in.
So write this in stone.....never mix old and new cam/lifter parts......and as a measure of good engine building, always prime the oiling system prior to starting a fresh build so there's oil and pressure from cranking and at the very start. When running a hydraulic or solid flat tappet cam, use a zinc additive with your oil, or use a good grade Racing oil, which should have higher levels of zinc in it, to help in lubricating the cam/lifter wear in.
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#17
(09-24-2018, 10:11 PM)Yep Spike Morelli Wrote: GeoBW,
              Your comment " They seem pretty bullet proof and worn in"  is correct, but what you're not understanding, is that the cam and lifters don't wear in to the block, rather they wear into each other, and once broken in, are now a team. You cannot use a new cam with old lifters, or use an old cam with new lifters. Many a fool has tried to disprove this by doing so only to spend more money replacing it all down the line. Oh, It'll run, but the components will wear each other out after not too long.Don't even consider it!
             When one "breaks-in " a new engine, it is customary to start it as quickly as possible, and bring the RPM up to 2000-2500 and set it there for maybe 20-30 minutes. At this time checks are made for any leaks of coolant , fuel, and oil. What your engine is really doing at this time is mating-in the cam and lifter surfaces together, and the RPM is a speed chosen by Automotive engineers where the rods, and crank is throwing the highest volume of oil at the cam and lifters, ( lubricating the cam and lifters ) while not revving too high...…..your rings today, are made of superior design, as compared to the old days, and will break-in very quickly, sometimes in minutes, especially when a Moly-faced top ring is used. So....to recap....break-in is primarily for the camshaft and lifters. The exception is when using a roller tappet cam, break-in is non-existent.
              Ever think about Drag Racing engines and their break-in? For the most part, they're ready to rev right off the stand, most racers are using a roller grind, ( no break-in ), and have rod, main, piston to wall, and ring clearances, etc, opened up as assembled, and will safely rev from the get-go without break-in.
             So write this in stone.....never mix old and new cam/lifter parts......and as a measure of good engine building, always prime the oiling system prior to starting a fresh build so there's oil and pressure from cranking and at the very start. When running a hydraulic or solid flat tappet cam, use a zinc additive with your oil, or use a good grade Racing oil, which should have higher levels of zinc in it, to help in lubricating the cam/lifter wear in.

+1 this is great advise.

73 Grandé H Code. Headman long tube headers, T-5 Transmission, 3.70 Traclok, Lowered 1" all around, Aussie 2v heads w/ 2.19 intake, 1.71 exhaust, screw in studs, full roller cam 608/612 lift 280/281 duration LSA 112, Quick Fuel 750 CFM double pumper, AirGap intake.

- Jason


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#18
(09-24-2018, 10:11 PM)Spike Morelli Wrote: GeoBW,
              Your comment " They seem pretty bullet proof and worn in"  is correct, but what you're not understanding, is that the cam and lifters don't wear in to the block, rather they wear into each other, and once broken in, are now a team. You cannot use a new cam with old lifters, or use an old cam with new lifters. Many a fool has tried to disprove this by doing so only to spend more money replacing it all down the line. 

Thanks for wading in Spike. And your right, I'm not understanding because there is no explanation. I will sound like a broken record here, but I have found in life that just doing things because people say to/not to without explaining the why is potentially misleading, boring at least and bereft of fascinating insights at best!

The cam face on the lifter is dead flat. I get a valve seating into its seat, and bearing faces wearing together, but the cam face shows no wear at all, I suspect it is hardened something +++. Money is not an object here, just to be clear. But I have found that asking why takes you into a much better understanding of engineering, particularly if you're changing things up. So my mind asks how does a lifter fail against a cam? I can see why to replace a 2-part valve - that was a spectacular example of great 'why' advice. Explain the why and you will have me at hello!

Cheers
George

Leave death a burnt out castle
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#19
Lobes for the 351C and any other flat tappet cam, are ground on an angle. This promotes lifter rotation. As the cam wears, that angle wears away. Likewise, the face of the lifters are ground convex, to mate to this angle of the lobe and rotate. Again, the face of the cam wears as the mileage piles up. The wear pattern starts as a narrow shiny band around the entire cam lobe. As the mileage increases, the wear pattern on the tip of the lobe gets wider. If the tip of the lobe is shiny it's full width, then the cam has quite a bit of mileage and should be replaced.

[Image: camwear.jpg]


During "cam break in" the engine is operated at around 2k rpms to promote lubrication of the lobe to lifter interface. During this break in period, the lobe and lifter mate to each other.


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#20
Thanks Hemi. I can see that it's important to break a new cam in patiently.

Cheers
George

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