Lavron's '64 Build Thread

[Rocket989]

Sure look like original bearings to me. I'd get some stainless lamp chain and hang one from the rearview!!

[poboyjo65]

Stroker! this is interesting to watch!

[lavron]

Went out and measured my bores again on the 250 block, this time I decided to do a bit more through job so I could determine what over-bore I might need.

Thought I would show everyone how I did it with just a couple of fairly inexpensive tools and what my results were for those that were interested, I am no expert at doing this and can't say this is the best or correct method and if anyone sees me leading folks astray here let me know the error of my ways

I used a set of cheap bore gauges that I bought off eBay, I don't remember how much they were but pretty inexpensive and they appear well made, I also used a digital caliper that I bought at the parts store (seems like in the $20-$30 range) I have had both of these for a while. I also drew a cylinder bore diagram of sorts but that really is not necessary you could just make columns on a piece of paper to record your numbers.



I measured each bore in this way; using bore gauge in each cylinder I measured at the top of the bore inline with the crank 3 times and recorded the measurement, then the same but going the opposite way (approx. 90 degrees) 3 times again. Then move down about half way down the cylinder and do it all over again, recording you results. And finally do it all over again at the bottom.

This is how you set the bore gauge, you place it in the location you want the measurement from, keep it as level and straight as you can, you can kind of move it around by feel to tell when it is fully extended and lock it with the knurled knob on top.



Then use the digital calipers to see what the size is.



I am holding the gauge crooked in the picture because trying to hold the camera in one hand while half way trying to show how you get the reading but don't do that, try to keep the gauge straight and use the same spot every time between the calipers (the calipers and the rounded ends of the gauges make it a bite to set in the right place a micrometer would work better but I don't have one)

After you have finished getting all 18 readings from each bore (on a 6 cylinder that is 108 entries) the fun starts

Here are the results from my block, you can actually tell I have honed #1 and a little of #2 before I broke my hone stones;

250 ENGINE BORE CHECK

Ford 250 L6 factory bore = 3.68”

Average of 3 separate measures per cylinder performed at 3 different depths, top, mid and bottom of bore. one check inline with crank and one at approx 90 degrees, this equals 18 measures per bore (6 at top - 3 inline, 3 perpendicular and the same mid and bottom)

CYLINDER #1
TOP inline 3.6955-3.6955-3.697=3.696(avg rounded up), perp. 3.689-3.6895-3.694=3.690; this would be .006 out of round.

MID inline 3.6825-3.681-3.6825=3.682, perp. 3.684-3.6845-3.6855=3.685; this would be .003 out of round.

BOTTOM inline 3.680-3.6815-3.6805=3.681, perp. 3.686-3.6835-3.6835=3.684; this would be .003 out of round.

The cylinder tapers .015 from top to bottom (using largest to smallest measurments)

CYLINDER #2
TOP inline 3.6865-3.694-3.6885=3.690, perp. 3.6895-3.694-3.6875=3.690; this would be .000 out of round.

MID inline 3.682-3.685-3.6815=3.683, perp. 3.6835-3.6825-3.681=3.682; this would be .001 out of round.

BOTTOM inline 3.6815-3.6815-3.682=3.682, perp. 3.6835-3.6805-3.683=3.682; this would be .000 out of round.

The cylinder tapers .008 from top to bottom

CYLINDER #3
TOP inline 3.6855-3.6935-3.6875=3.689, perp. 3.689-3.6905-3.687=3.689; this would be .000 out of round.

MID inline 3.681-3.6805-3.681=3.681, perp. 3.680-3.682-3.684=3.682; this would be .001 out of round.

BOTTOM inline 3.680-3.681-3.680=3.680, perp. 3.683-3.6835-3.680=3.682; this would be .002 out of round.

The cylinder tapers .009 from top to bottom

CYLINDER #4
TOP inline 3.6855-3.6795-3.6945=3.687, perp. 3.6875-3.689-3.6855=3.687; this would be .000 out of round.

MID inline 3.6825-3.6815-3.6815=3.682, perp. 3.684-3.6805-3.6815=3.682; this would be .000 out of round.

BOTTOM inline 3.6795-3.680-3.6805=3.680, perp. 3.6835-3.6835-3.6805=3.683; this would be .003 out of round.

The cylinder tapers .007 from top to bottom

CYLINDER #5
TOP inline 3.678-3.6825-3.6885=3.683, perp. 3.6885-3.688-3.6875=3.688; this would be .005 out of round.

MID inline 3.6815-3.683-3.6815=3.682, perp. 3.683-3.6835-3.6825=3.683; this would be .001 out of round.

BOTTOM inline 3.680-3.681-3.680=3.680, perp. 3.681-3.6805-3.682=3.681; this would be .001 out of round.

The cylinder tapers .008 from top to bottom

CYLINDER #6
TOP inline 3.690-3.6885-3.6935=3.691, perp. 3.690-3.692-3.6895=3.691; this would be .000 out of round.

MID inline 3.681-3.6775-3.6815=3.680, perp. 3.6855-3.6865-3.6845=3.686; this would be .006 out of round.

BOTTOM inline 3.6775-3.680-3.679=3.679, perp. 3.6795-3.6815-3.6815=3.681; this would be .002 out of round (probably closer to .001 oor because first number is most likely 3.680).

The cylinder tapers .012 from top to bottom

Averaging each bore; #1=3.685, #2=3.685, #3=3.684, #4=3.683, #5=3.684, #6=3.685 for a difference (largest - smallest) .003 amongst the bores, and a maximum of .005 over stock size, guessing a .020 overbore would true all the bores.

Unless I messed up, as far as bore goes, this engine is a good one as long as there are no cracks.

A question for everyone; Should I go ahead and hone the cylinders to get out all the ring marks(wear) and re-check or not worry about it and do the 20 thousandths overbore?

Mostly I would like to order my pistons sometime soon because I have no idea how long they will take to get here and I have found one supplier so if something happens I can't get them in like .020 I could get .030 etc.

See Ya,
Mike

[Rocket989]

Mike - I would have it bored the .020!!

[popscomet]

WHEN YOU HAVE A motor bored..lots of times they will bore it to the piston they have in stock....that happen to me yrs ago on a 240 ci 6cyl,,,20 would have been all it needed...but the machine shop had a set of 40's ,so that was what they bored it to.....if your doing this at home ...you need to wait and get the block bored ...1st....jmo....

[poboyjo65]

First I'd find out for sure what size pistons are available & I'd have it vatted & bored to the .20 if pistons are available , they will hone it afterwards.everything will be nice & round & true again. you never know what might happen, they could make a mistake,or something like Pop said so I'd wait about ordering them until the boring is done. I'd have them install the cam bearings while it is there.

[lavron]

Well the biggest issue is the pistons are a bit on the rare side so if I get it bored .020 over and can't get the pistons that would suck to have it rebored for .030 pistons.

That is why I am spending this time now not that I am just goofing around to check these things, that is why I made sure I had my rods because they are hard to find. It is not like the V8 world where there is a variety of parts available. The rods are reconditioned because no one makes new ones, the pistons are only made by Silvolite and I have only found one supplier, not saying they could not be special ordered.

If all else fails I could put Tempo pistons in it but they are flat tops and CR would go way up so I would have to have a dish milled in the top and that would add to the expense, or have custom made pistons but would rather pay $150 instead of $500+

See Ya,
Mike

[lavron]

Short work day because today is a school day but yesterday I picked up a second adjustable rocker assembly, a '60-61 Falcon donated it to me (well after I paid $10 for it) it was greasy and grungy so I cleaned it up a little because the grease on it will almost not scrub off your hands. I am going to dismantle it later and get it really clean and I may combine two to make the best one out of them.



You can see it just took me a little bit to make it somewhat cleaner.

Below is a comparison of the 3 I have, the bottom one is from the '72 Maverick and is non-adjustable. There is a difference with the front mount base (middle assembly the "new" one), it has a little oil pressure relief or a spot to dump oil on top of the head, not sure if that would be a requirement with a solid lifter motor



Finally this is a picture of the wear on the rocker arm faces.



The top assembly in the picture has better faces so I may use it, have to decide if the extra oil on top of the head is a bad thing. I got the top rocker assembly from a member here and it was missing one adjuster, I also noticed today another one was cracked, but now I have a few extra adjusters so I can replace them.

See Ya,
Mike

[Lip Ripper]

5 cylinders, really rare.

[poboyjo65]

5 cylinders, really rare.

????

[Lip Ripper]

10 rockers,

[lavron]

Each stand has a pair of rockers, there are 6 stands.

See Ya,
Mike

[redhotcomet]

10 rockers,

Image is being cut off I reckon. I only see 11 rockers until I open the pic in a new tab.

[lavron]

Another quick day, my wife is on vacation so spending time with her,

I did get a chance to pull the main caps out of Purple Power where they had been soaking the last couple of days, nice and clean



See Ya,
Mike

[lavron]

I know I am supposed to leave this alone but I got my pressure washer fixed and thought I needed to use it, so I used a little aircraft remover on the block and sprayed it off inside and out with the pressure washer.



I also put it in a tote and am going to give it a good bath in Purple Power as soon as I buy more today.



Barely fit, couldn't sit it upright

Not sure how much a 250 bare block weighs but I am going to bet between 75-100 pounds, I can pick it up and carry it but wouldn't want to go too far, the hardest part is setting it down gently because the floor is a long way away I may have to use the engine hoist to pull it back out because it will be all slippery. (and clean, I hope)

Soon as the block comes out I am going to put the head and crank in there for a good de-greasing

See Ya,
Mike