641 Cylinder Head

[Steve255]

I have ordered a set of pistons, rings, bearings, bushings, and gaskets etc. I have a hole in piston 1. I have the tools to replace the valve seals in my head, most shops want 200 dollars to go through the head for me. Is there a "Do it yourself" method of checking the head? The head is very clean and the valve seats look very clean. I just dont want to pay 200 dollars for some un-necessary work.

 

[Old Ford Mechanic]

Let me get this straight.You have purchased everything you need to overhaul your engine.But you are going to only install a set of valve stem seals and call the cylinder head alright.What about the valve seats and the facing on the valves themselves?And what about the surface of the head.Is it level? And don't forget the valve guides,a set of stem seals won't help if they are worn out.And while we are at it,did you mic the cylinders in the block for wear before you orderd new sleeves?Won't help much putting a standard piston back in a worn egg shaped hole.And how about the crankshaft,did you mic it for wear.Have you checked that oil pump? A lot more to repairing an engine than just ordering parts.To answer you question,yes there is a do it your self method to checking a head.You can also repair it if you have the correct tools and the knowledge required.If not i'd recommend letting a shop handle this.

 

[Operator4100]

Hey there, Have you checked around for other machine shops, I had my head done, engine boiled out, crank ckecked and all the other goodies for around $700.00 thats with the flywheel being turned to, well pleased with the price thou mine is a 172 engine (no sleeves) as for the head ,the machine shop had to knurl the valve guides so you might want to check around you've spent some money on it alittle more might be worth it in the long run, good luck. Dw

 

[richardp3]

I'm with the others, don't skimp on the head (or any other area of the rebuild). You don't want to put it back together and be second guessing yourself.

These heads are bad about cracking around the #2 and #3 exhaust valve seats. Be sure the shop checks for that. It'll cost you another $100-$200 to have small cracks stitched.

On my first rebuild I read and re-read every page of the service manual, and I'm glad I did. Plenty I would have missed otherwise.


Doing it right is well worth the satisfaction and longevity you'll get out of the machine.

 

[john_Bud]

The valve guides in the head can be pressed out and new ones (about $2.50 each) pressed in. Don't knurl them - it's a waste of time when you can press new in. I would sincerely wonder about the shop that told you that as they may not know diddly about Ford's. The springs are VERY weak to start with and may be too weak now - check them. The valves / seats can be lapped if they are in good shape to start with. But, that is an experience judgment call. Head flatness can be checked with a large machinists straight edge. Go corner to corner and see how much of a gap there is. At 0.002 it needs to be cut flat. The block should also be checked the same way.

I would check around on head refurb prices. Around here you can go from $75 to well over $1000. Naturally, the quality and extent of the work is way different. $200 is in the range that a quality shop charges. (But re-read my concern above)

jb

 

[Dave in MS]

You got some good advice from the others but I want to know what caused the hole in the piston. If it was piston/valve contact you certainly need to have the head and valve train checked.

 

[Steve255]

I'm taking the Head to a shop tomorrow. Not sure
what caused the hole in the piston, no damage
anywhere else. Each piston has a small divot
engineered in the center of it, number one went
all the way through. Not sure what would cause
this. Thanks to all.