Since I am waiting on differential and front axle parts I opened Shirley's Motor to see why she has low compression. The head is off, I opened the valve cover, opened the bottom pan and took a piston out. I don't have a bore micrometer yet. I have the engine book but have not read it all yet.
Here we go:
This valve doesn't look too good.
Actually I think the plug is seeping water and it is running into the valve chest which results in rust on the valve and spring.
The rods look OK, were there any shims so you can adjust to 0.002 to 0.0015"
I use copper washers on the inspection pan bolts, eliminates all oil leaks. Cut them to the correct length just to avoid any interference problems.
Yes, I found antifreeze water in the valve area today which you can see in the picture. Last month when I first got the car it had a stuck valve. I took the head off freed the stuck valve then put it back on. I did not open up the valve cover. I was in a hurry and did not look things over. The head leaked some before I torqued it down harder. I don't know if it is leaking now or if this is just left over from the previous loose head.
No shims. I don't understand "Cut them to the correct length just to avoid any interference problems." cut what? The washers? Where do you get copper washers for this? One bolt in the picture had a nut on it. I wonder if it is stripped in the block?
Ignacio: The rods look ok...but the missing babbit would cause me concern
I would be checking all bearing surfaces while I had the engine apart because when the babbit starts "chipping off" it can only get worse.
Can't see much missing Babbitt there? Ford didn't put any shims on the rods in a new engine - you were supposed to adjust by filing the cap.
When the babbitt starts to fail, like flaking off larger pieces, then it's time to rebabbitt the rods. Spare rods from Ford had shims to be able to adjust them to different worn cranks.
If the crank journals are worn oval, then it's time to grind the crank round again - time for a full restore.
Measure the cylinder bores - if too much wear you may want to rebore and fit oversize alu pistons, but if not too bad, a hone job and new rings should be fine for lots of local cruising. A valve job will also help compression.
@Roger thanks for responding, I am looking to borrow a cylinder bore micrometer now. I suspect the valves. The engine book page 12 says 'if the valve seats are well worn' but I don't know how to tell if the valve seats are well worn?
Here are what the top of the valves look like and a picture of the cylinder. Look Ma no piston!
You have the original style two piece valves that were made of a steel pin with a cast on iron head. These days, after 90 years of corrosion, they have a nasty habit to break at the join between cast iron and steel, so new valves might be a priority. You may find good used Chxxvy 350 V8 exhaust valves cheap that can be used - or buy from the vendors for $8 a piece (and well worth it)
Lang's lists 3 different types of valves: stainless standard size, stainless oversize and modern. Do I get stainless standard or what? Should I get new springs, seats and pins too?
In the engine book you have the data on how much force there should be in a good spring when it's compressed to a certain height. Use an old working bathroom scale and your calipers and squeeze your springs in a large vice together with the scale. If they're within specifications, no need to buy new. I've seen new ones that were unnecessary hard - may wear out the camshaft without any benefit. You may also need the small pins that holds the seats. If your Ford valve spring retainers are good, no need to change them for repro.
Check the wear in the valve guides - if worn too much, you need oversized valves and a reamer. No real need for modern valves - then you'll need modern spring retainers and split keepers too.
Check the top of the valve lifters - if the old valves have worn dips in the lifters, then you may want adjustable lifters too.. (just opening up the engine for a little check out tends to add up..)
Found a number here at the forum, the valve springs are supposed to register 24-28 pounds when compressed to 2 1/8".
But the rusty spring should be a candidate for replacement if it's pitted by the rust, that would be a starting point for a break..
(Message edited by Roger K on January 25, 2017)
@Roger at the risk of showing my ignorance what are valve guides and lifters? I have looked on Lang's and for diagrams of what that is and I am not finding them.
Ignacio, check on the top of the piston carefully and see if you can see if the pistons are std. or if they have been replaced with oversize years ago. It may be kind of hard to see the but it would be worth a look. If they are std. it would say STD. Of course you could Mic the bore to see.
It says STD.
The valve guides are the holes in the block where the thin valve shaft goes. It guides the valve so it goes straight up and down and doesn't "shudder" when closing. Remove the valve springs and stuff, put back the valve in its guide, hold a finger tight on the bottom hole in the guide and lift the valve rather fast - if the valve guide and the valve isn't worn too much, you'll hear and feel a "plop" as the partial vacuum is released when the valve leaves the guide. No "plop", then it's time to ream and put in oversize valves.
The lifters are the mushroom shaped parts that follows the cam shaft in one end and pushes the valve with the other end
Are there any other T'ers in your area? Maybe a club? You may need some local hands on help?
It sounds like you wish to learn and do as much as possible your self, but it's not as simple as buying new parts and fitting them, you will need help from someone who knows what they are doing, start by finding local club T owners who maybe able to help you.
You might find this thread helpful regarding the valves and lifters:
Unless you're going to completely rebuild this engine I wouldn't pay too much attention to the bore dia. or taper or out-of-round. There's nothing you can do about it now anyway without major work.
If it were mine, and I just wanted to freshen it up, I would remove all 4 pistons, buy new standard size rings, (for original style pistons) & hone the bores to break the glaze. Then replace & fit all the valves with new stainless steel ones that aren't prone to breakage like the original ones you've got. Wouldn't be overly concerned about excessive valve or tappet guide clearance, for the same reasons I wouldn't be concerned about bore size. And, for heaven's sake, buy a new head gasket this time, then button it up and try it out. Model T's are hugely forgiving and you should be o.k. to drive it around town.
None of what these guys have told you is wrong. However, unless you've got the ability and equipment it won't do you a whole lot of good, except for having a greater understanding of what you have, which IS valuable. My best advice to you is to find a reputable Model T engine rebuilder near you. Barring that, my advice above would be my second best.
I will say, I admire the fact that you've not become discouraged! Keep it up my friend!
As Jerry posted, there is fun in doing just a 'tune up rebuild' to learn about the T motor.
Did that as teenager, had a running T, but ran poorly and knocked. Pull the head, cleaned off all the carbon from cyl. head and upper block, pulled the pistons, marking each to therefrom they came. Noted the marks on the rod ends and caps to keep the same sides together on the same rod and cap.
Didn't replace the two-piece valves as didn't know about those. Pull each valve, marked it, and lapped the valves and seats with paste.
The lifters seemed OK, and reused the springs without testing. As for setting the valve timing, use the Fahnestock piston measurement method. Made a little scale tool to measure drop of the piston, and rise, with a pencil list of piston, can't believe I kept that work all these years in this FordOwner book!
Had #1 rod with some missing Babbitt, so got a rebuilt rod for it from J.C. Whitney. The other rods and caps have nice gray all over contact, and Babbitt seemed thick enough, not thin. No shims, so dress filled the caps and got them fitted tight, checking with brass hammer taps for slight side to side movement.
The new rod and cap needed to be scraped to fit, so got a Babbitt knife and fitted the new one. Got nice mostly all over gray contact surface.
Re-used the rings, got a ring compressor tool to replace the pistons. Added new gaskets, and buttoned it all up.
The T ran very good, with no knocking after that! Was a surprised kid, with no helping other than the Service manual and Fahnestock's book. I did a 'rebuild'
Maybe that is why I love the ole T so much, its forgiving for the new owner. A Model T just wants to keep on ticking!
Did you get the bit about the copper washers for the inspection cover bolts sorted out? If not, perhaps try a good hardware store, bring a bolt with you and ask if they have any copper washers to fit your bolt. Tony was talking about bolt lengths for the cover and remember this for your head bolts when it's time too.
Sorry that I'm repeating this if you already have it sorted. :-)
I'm excited to see the valves and seats! Just to see how bad/good they look.
Jerry is quite right about a T engine being hugely forgiving.
Don't tell anyone but nearly 20 years ago, I didn't have nor have access to a valve grinder and I used a drill and my bench grinder to clean up the faces on the valves in my '19 engine. I also hand cut the seats in the block and Voila! Almost guaranteed to start in three pulls of the crank or less! Well this coming spring/summer...
If you don't have a valve spring compressor, see what you can conjure up to get the job done. A fella from Indiana that's long gone once told me and my buddy as we were talking with him "If it works, that's the right way to do it." He's right. :-)
Do check out Royce's excellent valve/lifter thread. I don't believe you'll be too concerned about valve lift dimensions right now as long as they all go up and down but the info is fantastic to remember for later down the road.
Much good info here in your thread! Always watching for your posts! I was typing when Dan posted, I gotta read his post again! I like!
Rock on Ignacio!
(Message edited by Duey_C on January 25, 2017)
Dan, that post was just stellar. I look back in my books and find old bits like that and think wow, I was young. Your post blew me out of the water. That's neat!
Not wanting to date you but when was that piece of paper done?
@Roger I have 2 valves out. One plops a little. The other rusty one on cylinder #4 you can see in the picture does not plop. I can try on some of the others.
My rings actually look good to me and there does not seem to be a ridge so I wonder if it was ridge reamed and the rings have been replaced? How can I tell?
You should check very carefully the block in the area around the number 4 exhaust valve. Sometimes the block will crack around the valve seat. It looks like the leak was from the freeze plug, and hopefully it was. If rust is found farther up on the spring, the valve, or on the valve guide, it might be coming from a crack.
The rings on the piston should be along the sides perpendicular to the wrist pin, which is correctly shown on your picture, however, the slots on two adjacent rings should be turned to the opposite sides so that oil or compression is harder to leak out.
No ridge on T engine, top ring comes up to the top of the bore.
Glad you enjoyed my reflection, that scrap of high school tablet paper is now 53 years old.
That ' no plops' of the valve and stem, could be a bent stem, or could be that lifter is up and stem is hitting as it should on the lifter.
I think you'll find that well used rings, even if they still worked well and looked good, will not work well if removed and reinstalled. They have seated themselves very closely to the bores over the years but will NEVER go back in the exact same way. Because the bores are now glazed, there will be no "lapping" action to re-seat them in their new locations. It will burn oil.
Can I measure the cylinder taper with the crank in? If so, how? A Space City T's club member has a micrometer but he says it won't work with the crank in.
Will this method work? I don't have a bore gauge :-(
That's a telescope gage. Yes, that will work. Best to use it along with a micrometer rather than with a caliper.
Here's a long winded babble....
The telescoping gauges will work fine. Yes, the crank can surely stay in. The $25 cheapo set of telescoping gauges I've had forever DO have their limitations but I've gotten very accurate measurements with them too IF I'm patient and gentle.
Jerry is correct that a Mic would be best but a dial caliper might get you very close if you're patient and gentle. :-)
IF I remember correctly, the telescoping gauges are to be put in the bore at a slight angle, where you wish to measure, that knob on top loosened, the ends snap out, the locking knob snugged slightly and then with your index finger and thumb, gently move the "handle" across the bore so the ends of the tool in the bore compress/slide to get a true measurement as you slide it past upright. Do I have that right?
Think this way perhaps, put the telescoping gauge down in the bore, the handle is a little bit towards you at about 6 o'clock, the movable ends are at 6 and 12 o'clock, loosen the knob, the ends snap out, snug the knob lightly and then very gently push the handle straight away from you past the 12 o'clock position and you have your measurement as those movable ends should stay where they are. Pull it out and measure. IF you get a set, play with 'em. :-) They're kinda cool!
The blasterforum used it so you put it there straight up and down, lossened the knob on top and then snugged the knob on the "handle". I, personally didn't dig that too much.
You need help with that? I or someone will help. I know I felt a little silly the first times I used mine. Then I scratched my head the next time I was getting different measurements. Patience Duane, patience.
To be honest, right now, who cares what the bore is Ignacio?
Please remember my Crappy '24 T in my profile pic, that '19 engine is pure JUNK! It starts by hand cranking in three pulls or less. True. :-) I babbled about that just above on the 25th. I have TWO cylinders that have pretty fair compression and the other two are really bad when I crank it. Once running, it picks them off just perfect! A little weak for a 20 horse? Yes. It never fails me tho. It is most likely a very original engine, no rings, no nothing until I gave it a crappy valve job . I've never had that engine apart. It's a wreck.
A little compression is all you really need. More is great. A complete rebuild is even better!
The '26 engine in my '24 TT also starts on three or less pulls on the crank with a Vaporizer carb. I have never had that engine apart (except the head and valves) nor cared how the rings looked. I was just getting it running and it ain't too bad! The compression? Ehh, not that great.
I did an "afternoon valve job" and vroom! Well, tuttle, tuttle, tuttle, tuttle......Vroom! Runs pretty dang good.
Ooh ooh! Have you posted pics of the valves and their seats? You should know I'm itching to see! Valve action is where it's at for the crappy engines.
How do you lap the last valve for cylinder 4 with it difficult to access under the firewall?
That one is kind of a bear. I punted with the lapper thing really crooked. Guys?
The crank appears to be round with only .005 inch difference on 2 axes. The piston size is 3.733 inches with the ring edges sharp. Could the pistons and/or rings have been replaced?
You're saying that your crank shaft is .005 out of round? If so, that's huge. You will never maintain a good bearing fit with a .005 out of round crankshaft.
Your pistons & rings look original. It doesn't matter how sharp the ring edges are. Your cylinders are most likely not round, so your rings are not either. Since you will never reinstall them exactly as before, they will not seat.
What Jerry says is correct. You want crankshaft clearance of perhaps .002". No way to get there, your crankshaft is shot. Maybe it can be turned if there is enough metal remaining, and it passes crack check (typically magnuflux but some shops today are using ultrasound).
Same with the cylinders, they can be checked using telescoping gages and a micrometer, but you have to be capable of using the measuring devices properly. Most likely judging by the looks of things the cylinders need to be overbored, and the pistons / rings replaced.
Cylinder Upper measurement 3.7640 inches.
Cylinder Lower measurement 3.7525 inches.
I did more measurements but the paper it was written on was put in the laundry. These were the two remembered. The gist of the measurements was that top of cylinder and bottom of cylinder varied by .01 inch. Does that mean anything?
I will re-measure the crank to make sure my measurements are correct.
So page 11 of the MTFCA engine book says 'As a general rule, if the cylinders are tapered more than 0.01 inch they should be bored.' I think I am lucky.
Crank re-measure is 1.2455 and 1.2430 which is 0.0025 so since the engine book page 37 does not go to 4 places of precision I will take as 0.002 :-)
Cylinder measurements front to back, side to side, 45 degree angle are: Top 3.7635, 3.7640, 3.7595, bottom 3.7520, 3.754, 3.750
How much out of round are the 4 connecting rod journals?
What is a connecting rod journal?
It's the 4 diameters, (journals), on the crankshaft where the connecting rods run. I think the crank dimensions you gave were for a main bearing diameter. The rod bearing diameters will likely be more out of round than the mains.
At my level of expertise or lack thereof I am hesitant to take more pistons out. I can handle the one I took out that it will safely go back into position :-)
O.K., thanks. That clears up in my mind then what it is you measured. Thanks.
How tight do you torque the valve cover on? Is the valve cover open like that right at the throttle rod? Doesn't oil come out?
Also is there a sequence to putting the exhaust and intake manifolds on?
Glands in, then copper ring over it then put manifold on?
How do you get rust scale out of a head? I flushed it hard with water and a bunch came out but more periodically falls out. Can I put small nuts and bolts in and shake it around? Is there a better way? A different non T forum said put it on a piece of plywood and thump it around to get the rust loose. Then said use vinegar or molasses but don't use hydrochloric acid as it weakens the metal.
So I thumped the head on a piece of plywood on the ground and a handful of rust came out. Wow.
John Tannehill showed me how to file piston caps and put in shims. Shirley's motor is now shimmed and ready to be closed up. I hope to have her all back together again this week.
I am still thinking about some method like some sort of brush to get the rest of the head rust out. I have a new Berg's and don't want that rust in it. I am thinking of removing the water pump too since it is supposed to not be necessary.
If you have a new Bergs, you definitely don't need that water pump--although I understand they make great wheel chocks.
What is the proper way to put in a oil pan gasket? I have copper washers for the bolts and permatex #2. Do I permatex both sides of the gasket?
Not that much oil ever really gets into the valve chamber so you shouldn't have any leaks out of the throttle hole. You will however, see some smoke or oil mist puffing out of there.