Engine machining

[rusty ol ranger]

Not sure exactly where to put this.

Anyways...some of you know about my LTD II/351W adventures in my build thread.

The engine in the car ran good...20 years ago. Untill the timing chain slipped and bent valves, etc.

I have the engine out of the car...and im up in the air with what to do.

Original plan was to regasket it, get the heads/manifold decked, clean it up and run it.

Then i got on the kick of rebuilding it.

I called my local machine shop. I got a quote of around 300 bucks to do a hone, hot tank, and cam bearings. Very reasonable and my gut tells me thats all itll need.

I went down the rabbit hole of line honeing/boring. Now full disclosure i dont want a 1500 dollar surprise if i tear it apart and take it in.

So what im reading is a line hone/bore is absolutly needed on any rebuild, some say dont worry about it, and some say its really only needed on high HP builds, which this is not. Its a stock, maybe a bit more, rebuild.

Ive done assembly and disassembly when we used to work on the mud trucks but i never dealt with machining. I was basically handed parts and told "put this togther" lol.

So im curious....what are the chances this will need to be done...should I have it done....or am i thinking way to much about this?

 

[franklin2]

You must hone the cylinders so the new piston rings will seat. There is a guy in a book I have that says if you are doing surgery on the engine in the car, and do not want to get metal particles in the assembled engine, you can get away with not honing that cylinder IF you use moly rings. He said it will eventually seat with moly rings. Otherwise, it doesn't make sense to not hone the cylinders and wait for miles and miles for the new rings to try to seat.

He also said, if the bores are worn up to .006, you can ridge ream and hone the cylinders, and expect some life out of the engine before it starts burning oil. He says expect about 50.000 miles out of a engine with the bores worn .006 out of round. Anything beyond .006, it's not worth spending the time and the money,, the engine will not last very long and have good ring sealing for very many miles.

So I am sure the machine shop will be diligent and measure the bores before honing. If they are worn, they will want to bore them and then that means new pistons. And then you have to pay to have the rods installed on the new pistons.

I have never had one of these old pushrod v8's bend the valves when the timing chain went. They are non-interference engines.

 

[Roert42]

Should be no reason to line bore the mains unless you spun a bearing.
Will cause more problems then anything if it’s not done properly.

put a piston in the bore with new rings, if you can’t see light past the rings,( check at the top, middle, and bottom of the stroke) then it’s round enough. Hone It, re ring it, and ship it.

the tool to change can bearings is not insanely expensive, but if you are going to have a machine shop check the block and hone it, it will be cheaper for them to do the bearings.

Make sure you clean out the coolant passages after they hot tank it. Gunk likes to collect in there.

 

[rusty ol ranger]

You must hone the cylinders so the new piston rings will seat. There is a guy in a book I have that says if you are doing surgery on the engine in the car, and do not want to get metal particles in the assembled engine, you can get away with not honing that cylinder IF you use moly rings. He said it will eventually seat with moly rings. Otherwise, it doesn't make sense to not hone the cylinders and wait for miles and miles for the new rings to try to seat.

He also said, if the bores are worn up to .006, you can ridge ream and hone the cylinders, and expect some life out of the engine before it starts burning oil. He says expect about 50.000 miles out of a engine with the bores worn .006 out of round. Anything beyond .006, it's not worth spending the time and the money,, the engine will not last very long and have good ring sealing for very many miles.

So I am sure the machine shop will be diligent and measure the bores before honing. If they are worn, they will want to bore them and then that means new pistons. And then you have to pay to have the rods installed on the new pistons.

I have never had one of these old pushrod v8's bend the valves when the timing chain went. They are non-interference engines.

Yeah i know about boring and honeing cylinder bores...i was talking about line boring/honeing...which trues up the main caps so the crank sits straight

 

[19Walt93]

I use River City Machine in White River Junction, Vt and he refuses to ream cylinder ridges and will bore the block instead. An engine will run with a sloppy piston fit, if just running is all you want. I don't remember ever seeing a Windsor family engine bend valves and I saw a bunch of jumped timing chains in the 70's. It was common for small block Chevys to bend valves when they jumped timing, though.
I've never seen a Windsor need to be align bored and wouldn't spend the money unless there's a reason to suspect it is needed.
If you luck runs like mine, do a thorough job or it will bite you.

 

[rusty ol ranger]

I use River City Machine in White River Junction, Vt and he refuses to ream cylinder ridges and will bore the block instead. An engine will run with a sloppy piston fit, if just running is all you want. I don't remember ever seeing a Windsor family engine bend valves and I saw a bunch of jumped timing chains in the 70's. It was common for small block Chevys to bend valves when they jumped timing, though.
I've never seen a Windsor need to be align bored and wouldn't spend the money unless there's a reason to suspect it is needed.
If you luck runs like mine, do a thorough job or it will bite you.

When i intially pulled the heads when this first happend...it had a couple bent valves, and bent pushrods. Couple knicks in the piston to prove it.

I dont know what else would of caused it.

Timing chain had about 2 inches of slop in it.

 

[85_Ranger4x4]

A hone and ring job is not a rebuild...

Done right it needs bored and new pistons.

And new valves, guides, seats etc.

 

[franklin2]

Yeah i know about boring and honeing cylinder bores...i was talking about line boring/honeing...which trues up the main caps so the crank sits straight

Unless you have a catastrophic failure, you never need to do this as was mentioned by one of the previous posters. All of the v8's have fairly good bottom ends, and give no trouble over many miles. Unless the oil was never changed, a new standard bearing usually is all it takes on the bottom end.

 

[ekrampitzjr]

A number of performance-rebuild books say you don't normally need to align-bore/hone the block + main bearing caps unless you're trying to rebuild for crazy power or you suspect the block or caps warped. If the crankshaft binds when rotated with the caps and a set of junk bearings in place to test, then you do need an align-bore. But that's rare.

To emphasize, we're not talking about rehoning the cylinders. That should be done with any serious rebuild, especially if the original hone marks are worn away.

 

[scotts90ranger]

I just freshened up the 5L in my Explorer, at 250k there were still factory hone marks on the cylinder walls, I just changed all the bearings and seals, honed, reringed and ground the valves and went for it... Unless there's a spun bearing I don't think I'd get too crazy...

 

[pjtoledo]

if you're worried about align boring, flip the engine over, crank up, remove crank.
lay some plastic-gauge on the main bearings, install crank & caps, torque, then remove crank and compare the clearances.
DON'T ROTATE THE CRANK

you should gauge all the new bearings anyway.

if there is any ridge it will need removed.
the location of the ridge was created by worn rings and worn bearings.
new bearings/rings will push the rings up farther, not much. but enough to risk crashing the new rings into the old ridge.

 

[85_Ranger4x4]

if you're worried about align boring, flip the engine over, crank up, remove crank.
lay some plastic-gauge on the main bearings, install crank & caps, torque, then remove crank and compare the clearances.
DON'T ROTATE THE CRANK

you should gauge all the new bearings anyway.

if there is any ridge it will need removed.
the location of the ridge was created by worn rings and worn bearings.
new bearings/rings will push the rings up farther, not much. but enough to risk crashing the new rings into the old ridge.

The ring groove is made by worn out rings with dull edges. New rings will have sharp edges and get crammed into the radius of the ridge and can cause issues too.

 

[rusty ol ranger]

A hone and ring job is not a rebuild...

Done right it needs bored and new pistons.

And new valves, guides, seats etc.

The heads were done already when i had the valves fixed.

Athough pry wouldnt hurt to do seals again

 

[rusty ol ranger]

After a lot of thinking and kicking around in my brain i think im going to hit the (hopefully) easy button and find a good junkyard engine.

Ill probably still end up rebuilding my current engine for the point when the junkyard motor fails.

What plays into this descion is my current engine is missing ALOT of stuff. Random bolts, brackets, shit ive stolen over the years for other stuff. Also i can atleast get the thing moving under its own power so i can move it around without a tow strap...it would make alot of the other things i wanna do to it alot eaiser.

Im going friday to check out a 351 H.O from an 86 Econoline for 500 bucks. Its still in the van so i can hear it run. From what ive read i will just need to swap flywheels to get it to work, as well as put on my front sump pan and pickup tube.

Assuming the engine is healthy ill pick up quite a bit in power...the 77 is rated at 149hp and 291ftlbs...The 86 is 210hp and 315ftlbs.

Im *hoping* the fact that its in a van its probably led a bit eaiser life then one in a pickup did. But who knows. It will also make it much more of a bitch to check over good lol.

But i figure for 500 bucks its worth the gamble.

Any thoughts?

 

[alwaysFlOoReD]

86 will be fuel injected? Take the whole thing home if so.