All Small Six 200 head bolt thread chaser vs cutting tap.

This relates to all small sixes

Ironhorse

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Hi all. I’ll soon be replacing the head on my stock ‘66 200 and I’d like to make sure I have all the necessary parts and tools ahead of time. I already have the gasket from NPD. I’m planning to reuse the stock bolts assuming they are in good shape. I’ve read I should use a thread chasing tap vs a cutting tap to clean the threads in the block. Can someone confirm chasing vs cutting vs doesn’t matter ? Also, is a 7/16-14 the right size ? Any other tools or parts I need for this job ? Thread sealant type ? I have a nice Craftsman torque wrench although it’s never been calibrated.

I‘d like to measure the bores to determine how Worn they are but I’m not sure what tool to use for that.
Any advice / direction appreciated to maximize the value while I’m in there.

thanks
 

bubba22349

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Hi Ironhorse, the Ford 200 has a 7/16 X 14 UNC thread pitch for the head bolts and the blocks head bolt holes. It's best to use at least a bottoming tap or better still is a thread chaser over the tappered thread cutting taps as they won't reach all the way to the bottom of the blocks blind holes to clean out all the rust, dirt, or crude. Good luck
 

TrickSix

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The passenger side front head bolt protrudes into the water jacket - put some sealer on that one, and take care that it doesn't impinge on the water pump impeller. Also, look at your '66 head bolts, they're a constant diameter shank. Newer head bolts, like on your '79 250, have a reduced shank diameter. Use of one of these "necked down" head bolts in the rear drivers side position (where oil comes up from the block around it to the head) will increase oil flow to your head.
 

drag-200stang

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Yes it does matter, you can lose thread material using a tap , a chase would be best...But in typing that, I have carefully used a tap before.
 

B RON CO

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Hi, the if your original head bolts are all full shoulder the "trick" for the left rear bolt is to grind three flats lightly onto the shoulder to allow more oil flow to the valve train.
Your torque wrench should be fine. You want the head bolts to all be the same even tightness, rather then an exact #. You probably know to tighten clean bolts down in 3 steps, and double or triple check after the final go round,
Good luck
 

alwill923

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Get a set of metric and SAE thread gages. They are cheap and well worth having as many cars today mix american and metric. ARP has thread chasers but are not cheap. I would be careful of cheap thread chasers as they could damage the threads.
 

Ironhorse

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Great input, thanks everyone. I’ll swap one of the 250 bolts in to the left rear as suggested. I saw the ARP chaser for $34. Beats the alternatives (messed up threads). Once I’ve used it, I’d be glad to loan it out to you guys if you need it, just drop me a note. I borrowed some bore gages today. Now I just need to find a mic big enough to measure it. I have good quality verniers as a last resort. Picking the new head up this sat. It’s been fully rebuilt including hard seats and guides. Hoping for a big improvement in driveability once my leaking intake valves (2) and oil sucking guides are gone.
 

Ironhorse

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Is corporate blue the correct shade for a 66 200 ? Im considering Eastwood engine paint (used it before and loved it) or POR15 corporate blue or ??
 

bubba22349

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Yes for the 1966 year models and most of the rest of Ford 200 and 250 Six engine production to about the end of the 1979 they were no longer color keyed to the specific engine models, all Ford engines were now painted a Ford Corporate Dark Blue. This was the new color for all Ford engines for 1966 and later. As with before the entire Engine long block was painted after it was assembled only the the valve covers were painted separate and than installed on the engine with the natural finish metal bolts with the special integral lock washers same as the earlier engines. The exception to using this Dark Ford Corporate Blue color were on the last of the 200 & 250 six engine production for the 1980 to 1983 models, to add some further confusion many auto parts companies market 3 different Ford Blue colors.

In 1966 to 1972 the 170 six'es were also still being used they were the base engines in the Falcons, Comet's, and the new debut in 1969 1/2 of the "1970" Maverick's. They are also painted the same Dark Ford Corporate Blue as the 200's and 250's see below for example. The picture is of a 1966 200 engine these later model 200's had air cleaners that were made a little different from the early 1963 1/2 to 1965 engines. The Sports Sprint models had a chrome air-cleaner housing, as did the 1966 Mustang Sprint 200, made available during Spring 1966.

1966 up Falcon, Fairlane, Maverick, Comets, and 1966 to 1973 Mustang 200 six Engine Color Reference
Engine/Part Color
200ci valve cover Dark Ford Corporate Blue Duplicolor's DE 1606 Dark Ford Blue or Plastickote # 224
200ci air cleaner Dark Ford Corporate Blue Duplicolor's DE 1606
200ci block, head, oil pan Dark Ford Corporate Blue Duplicolor's DE 1606

1966 Ford 200 Six


Fords small sixes from 1966 up to 1972 for the 170 Six's, the 1966 to 1979 200 Six's, and 1969 to 1979 250 Six'es used in the Falcon, Fairlane, Maverick, Comet, Granada, Monarch, " the 250 six in the 1969 to 1973 Mustang's" were also painted that same Dark Ford Corporate Blue. For the 1966 up color of Ford Corporate (Dark) Blue, Duplicolor's 1606 matches this. Some other brands that also match the Ford Blue are Krylon's Ford Dark Blue and Plasticoat Royal Blue 1134. For the accessory parts like pulleys, fans, starters, alternator brackets & belt adjusters, etc. these were all painted Semi Gloss Black a good match is Duplicolor's 1635. Good luck on your restoration. :nod:
 

drag-200stang

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In case you did not know the intake/exhaust side of the engine the front and rear, gasket and head holes are smaller than the rest and the reason for that is to put two pins or studs there to align the head and gasket properly...Take two long enough full shank bolts and cut the heads off and hack saw a slot in them for a screw driver..Put them in the block then the gasket and then the head..Once the rest of the bolt are in and some torque, take out the guide pins...Sometimes the pins need to be modified if the threads show and then the gasket can get pushed into them and not get good alignment.
 

chad

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If never done B4, no 1 experienced to assist, I'd read a guide 1st (may B twice?). I have only read the 1st post (yours) & see you may B a lill off on some stuff, I don't re-use (head) bolts. Just not understanding the difference btw a tap w/cutting thread to the bottom v ones that shrink in size @ bottom is not a "don't rebuild ur own block" exclusion. It does mean U may think this is an easy experience. It is not and $/X can B lost, the builder become disilliosioned,
Congrats on standing up to the challenge, good luck, get some local help. We're "pretty far away". Books R highly recommended as 1st steps.

/ALSO/
above ,very top, blue horrizontal line

posts #4, 6, 12 above are not enuff to do the job...
 

Ironhorse

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Thanks Chad. Warning received. I now have the Falcon Performance book in hand and plan to read it carefully before swapping heads. I also bought the ARP thread cleaner for the job (darn expensive little sucker). Curious how many are using head bolts vs studs ? I’d use ARP either way and understand the torque specs are different.
 

Steve N Grace

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Hot Rod did a really good article on engine fasteners that is available on line. Here is the link.


If you want to go deeper, there are a couple of good automotive fastener books on the market too. Fascinating topic for us engine geeks....
Cheers
 

Ironhorse

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Excellent article Steve, thanks. I remember being shocked the first time I heard that 85% of applied bolt torque is wasted in friction, leaving only 15% to stretch the bolt. I can also confirm from tests we ran at work that bolt clamp load with lubricated threads can be twice as high, or more than when using dry threads. That can make the difference between bolts coming loose over time or failing due to fatigue loading, depending on how the torque spec was developed. I’m going to start a new thread to see who is using head studs vs head bolts. I realize studs are overkill for a stock 200 like mine but even so, I’m leaning that way.
 

chad

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...read it carefully before swapping heads....Curious how many are using head bolts vs studs ? I’d use ARP either way and understand the torque specs are different.
every motor is different (lots of difficulties to hop up the cheb 292 for example). Understand the 2 or 3 places for APR here'n increase oem's capacity AND save $ (dont need them everywhere). You'll C in "the Handbook" &/or above 'tech archive' studs R liked for clampin pressure & assembly (just slide it over'n down 2 or 4 studs waiting).
 

chad

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with that name (I assume a bronk) we gotta stick together.
Bigger heard isa stronger/healthier heard
8^ 0
 
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