I have started tearing down my motor to replace the chewed up ring gear on the flywheel. I have the car completely apart and figure that it would be stupid to leave the ring gear and not fix it. The motor was already out and on the stand so it makes sense to just deal with it now... I have taken off the hogs head, I have pulled the oil pan off as well as the head.
So, My questions for now are:
1. The underside of the pistons have a ton of carbon on them. The pistons are tight in the cylinders and I don't think that I need to do rings. The motor has been apart before and everything appears pretty solid so I don't want to mess with taking the pistons out. What should I use to get the carbon off the bottom of the pistons? Would oven cleaner work? Would it be okay to spray it inside the motor? Any other ideas...
2.The drain plug on the bottom of the oil pan is a bit off. I'm not sure what happened. It doesn't look like it is bent or damaged but the plug that holds the threads is a bit weird. Not sure what to do with it. Leave it alone or try to fix it while the pan is out. The plug threads into it fine.
3. Has anyone seen lifters that have little tiny shims that sit in a recessed cup just under where the valve stem sits? I don't think these are original. I think they are fine but wondered if anyone knew anything about them.
The cup things were common after market items to take up tappet clearance.
Looks like someone added roofing tar to quiet the engine down.
That's not carbon deposits like you find in the combustion chamber, it old dried caked on oil and dirt deposits from not using detergent oil.
As long as the drain plug does not leak, no harm. I would leave it alone.
Depending on what type valves are installed at this point I would install adjustable lifters and get rid of those caps. The caps to me are a makeshift get by repair.
Without testing I could not recommend using oven cleaner for the inside. I don't know what it would do the the babbitt. I would use a solvent to clean not the water based purple stuff.
Yes, that caked on muck is typical of what happens when using non detergent oil. You can get it off with some kerosene and some scrapers and brushes.
After it's cleaned i would look long and hard at that oil drain in the pan!! To if only too me it would seem better to repair or replace before it bites you in the butt!!! Bud in Wheeler,Mi.
Your timing gear is worn out. The one on the crankshaft is likely no better. The fact that it's still a cast iron gear tells me your motor is probably pretty original inside. Have you considered just having it completely rebuilt?
Time for a complete rebuild
Your engine shows signs of some substantial wear. I doubt if much has been done with it since 1926 and it appears tired. I guess there's a few things you could do to keep it going but it appears to need a rebuild.
Mike I think you need to consider rebuilding the engine If you wanted to go this route you could do a lot of the work yourself and save a few dollars. If you want you can give me a call and I could give you some advice on going thru the engine and trans
Thanks everyone for your comments. I have been trying to avoid a complete rebuild.
I am fairly mechanical however I have never done any machine work and don't really have any of the tools to do some of the necessary work. I suppose I could take it to someone to do but I have been trying to do all of the work myself. That is half the fun of the project. Doing the work, learning along the way, and gaining a better understanding of how the entire car works.
I know that everyone has a different idea of what a "Complete rebuild" is, but does that mean, new crank, new pistons/rings, does this mean new babbitt, machined block, resurfaced head, etc....
I know you get what you pay for, and I understand that once it's torn down this far it makes sense to do the whole thing, and I have even thought "I'd hate to have to tear this thing back apart in the near future"... However, for now, this is just a small hobby (and one of MANY projects I have taking my time and money) so although I'd like to have a brand new shiny motor, I'll have to be okay with taking a few shortcuts to save time/money.
What are the MUST do's that would be stupid not to do at this point? (factoring in all I have said above)
Two ways to go. 1.Fix the ring gear and leave everything else alone. 2. Rebuild everything. The first way might get a few more miles out of the car but the second way, if done correctly will give you many years of reliable service.
If you don't rebuild, don't worry about the "carbon" on the underside of the pistons, but check all the bearings and adjust clearances. The timing gears might work a while longer, but will be noisy.
A question is this: Do you want to pull the engine over and over to fix one problem at a time, or get it done once for all?
If it were mine, I would rebuild it. If you are mechanically inclined, you can get the machine work done professionally and assemble and install the parts yourself. Or you can have it all done professionally.
At a minimum, check and adjust bearing clearances, hone the cylinders and put in a set of rings. Pull the camshaft and put in a set of adjustable lifters. Put a new steal timing gear on the crankshaft and an aluminum gear on the camshaft. Lap the valves. Check crankshaft end play.
Then there's a lot that can be done with the transmission. Check the strength of the clutch spring, take a good look at the clutch disks, measure clearances on drum bushings and triple gear bushings. Check the drums for cracks. Check the strength of the magneto magnets. Do a good visual of the magneto coil ring. Change ring gear. Check the balance of the drums, flywheel, etc. replace seals and gaskets.
Assuming nothing's cracked ( block, head, crankshaft, etc). You'll get a few more miles out of it.
If you've got a way to get the pan on a jig and check it out and straighten it if it needs it you'll have a chance to get a decent alignment on the fourth main. You might check clearance on the fourth main while you're at it. And, because it's a good time to do it, take a look at the universal joint.
"...does that mean, new crank, new pistons/rings, does this mean new babbitt, machined block, resurfaced head, etc...."
Yes. Maybe. Some of that, like the new crank and the resurfacing, may be needed, or may not.
As Norm says, you can do some of it yourself and have an expert do what you're not able to. Rebuilding once while it's apart will be cheaper and a lot less work than pulling the engine several times to do it in stages.
Assuming its current condition doesn't require more, a decent rebuild should include;
1. Magnafluxed & reground crankshaft.
2. Reground or new camshaft & cam bearings.
3. New valves & lifters.
4. Recut valve seats or valve seat inserts.
5. New babbitt.
6. Bored & honed cylinders.
7. New pistons & rings.
8. New timing gears, (no fiber gears!)
9. Resurfaced block, if needed.
10. Resurfaced manifold mounting face, if needed.
11. Check pan for flatness & straighten as needed.
I think that's about it.
Good advice here--but there is another alternative--and I would think the first thing to do when planning out what to do to your engine.
1) Measure everything--true, you'll need some micrometers to do this. By "everything" I'm saying to check the crankshaft journals for being round--if they are, and the babbitt all looks good, you might not have to pour bearings. Check taper in cylinders; the will determine if you can reuse those pistons or need to bore and new pistons. Check camshaft to see if all the lobes have the same lift--how do they look, worn on not? I would be surprised if you don't find that the engine has lots of wear and is due for a rebuild--but one never knows until you measure!
there is a lot of the engine rebuild assembly you can do yourself with just "ordinary" garage tools, but there's some of it that requires specialized stuff, like bearing pouring, cylinder boring, pan straightening, etc.
When you get done though, you will KNOW your engine!
David - I had the same idea. A lot of engines have been "refreshed" in just the way you suggest, and there's nothing wrong with that. And I think the most important thing you suggested to Michael was to "MEASURE EVERYTHING"! And measure properly. Here's what I mean:
As you said Dave, if the crank journals are round, and the babbitt looks good, there could be a real "shortcut" here. Sometimes when in the past, new main bearings have been poured, and a used crankshaft that has been machined due to out-of-round journals, that means that the main bearings were align bored to fit crankshaft main journals that were slightly undersized. That means that the main bearings were align bored to fit those undersized journals, which means that there is slightly more babbitt in those mains than normal, which means, there is enough babbitt to fit a crankshaft which has standard size journals, or, at least journals that are slightly larger in diameter than the crankshaft that was taken out. In other words, if another used crankshaft can be obtained with stock, or nearly stock diameter journals could be align bore fitted without having to pour new main babbitt journal bearings.
And again, in regard to careful and thorough measuring, you mentioned measuring cylinder bores to determine taper David, however, it might be kept in mind that you can get away with a couple thousandths taper, 'cause taper will merely cause the new rings to flex a couple thou' with each stroke. However, any more than one or two thousandths out-of-round cannot be tolerated, as the new rings will never seat properly in a cylinder that's more than one or two thou' maximum out-of-round.
Again, all of that to say that careful but thorough measuring might allow an acceptable money-saving shortcut or two,.....FWIW,......harold
Oops! First sentence in second paragraph should not have said,...."if the crank journals are round,".....
Should have said,....if in the past, the crankshaft journals have been ground slightly undersized in a previous rebuild, and the babbitt looks good......
Yes, you're right about the cylinder taper. I didn't give any measurements, as that info is out there. I should have mentioned that unlike most engines where you can tell the taper by the ridge at the top of the cylinder, original type rings on the T go to the top of the bore, so no ridge is formed.
Like some folks have said, when you work on a T, throw away almost everything you "know" about automobile repair!
And, of course, if the car is going to be a garage Queen, you can likely get away with a lot of stuff at the edge of wear limits. . .
David - Speaking of "getting away with a lot of stuff at the edge of wear limits,...."
When I was a kid in high school, I rebuilt a Model A engine for a '28 coupe, and did it all myself, except of course the machine work. Did it pretty much "by the book" in my parents basement, and I have to say, it turned out to be a pretty good engine that I drove all over Chicago for several years.
Now then, my friend who also had a Model A, also needed to replace his worn-out engine that had a cracked block, and you can believe this or not, he basically took the guts of his old engine, and simply put them in a rusty old engine block that he found laying outside in some field or something. (Remember, this was in the '50's when there was still old stuff laying around!)
Well, long story short, some time after we both got our engines re-installed and running, I went over to Tom's house one day, and his Model T was idling in his driveway when I drove up, and it was "pick'n 'em off" just sweet as could be. I said,....but Tom,....what about all that rust that was in those cylinders???"
His reply was,...."Oh hell,.....that's all gone by now!"
Sheeesh! And I spent all winter putting my engine together as carefully as I could, "right by the book"! No justice, right?
Yeah, plenty of gunk indicating years of use. Too bad you didn't take a comp test before tearing into it. You would have known the rings condition and possibly eliminated them as something else to do. Now let's face it. You can leave the cam follower caps there fix the ring gear & drive and nobody can tell you how long you'll go. Could be years on a car without much use. Then there's the replace the cam followers situation. This will involve new followers, new timing gear set and valve lapping (at least). It makes sense to go over the bearings at this point also. I absolutely guarantee you one thing: "The more you do the more you'll end up doing".
I like Jerry's list. My only addition would be right at the start. No1, Crack test the block.
It is good insurance to do this. All the other work is for nothing if there are cracking issues.
Hope this helps.
Allan from down under.
One engine that I rebuilt had standard cast iron pistons with little bore wear. I was able to have the block honed to fit new standard aluminum pistons which requir. The babbitt was good.....could have possibly used the original pistons however, I like aluminum/modern rings much better.
Get a copy of the original Model T Service Manual and the MTFCA Engine and Transmission Manuals if you have not already done so.
Put the head back on and do a dry and wet compression check. You should get 45 psi or more on the dry test, if there is much difference in the wet and dry test then you need new rings. Then check each rod journal for clearance, out of round and taper middle to each end. Check each main bearing clearance. You will likely need to fit a rebabbited rear main cap. Look at the crankshaft timing gear, if yours is worn like the crank gear you will need to replace it. Model T crankshafts are often but not always cracked. It would be a good idea to pull it and have it magnafluxed. While it's out you might have just the rod journals reground. In which case you would need a set of rebabbited rods. Replace the timing gear with a new aluminum one.
Check the fourth main ball cap, you may need a rebabbited one.
Your camshaft is likely worn. There may be a shop in your area that can reground it. If you set your valves by clearance with a worn camshaft it will not develop it's full power even with new rings and reground valves. Norfleet in Dallas Texas has reground camshaft for several in our club.
You will want to install adjustable lifters no matter what you do. Grinding of the valve stem to set the clearance is a real pain. If you get it too short there is no easy way to lengthen it.
Transmissions even though well worn will operate trouble free. The revers drum is often cracked in the web from someone using reverse as a brake.
Your Babbitt in the block is likely good and your main journals are likely fine. You will need to measure the rear main diameter in order to get the correct size rebabbited rear main cap. If you have the crank main journals reground you will have to have the block rebabbited.
A local machine shop could rebore your block for oversize aluminum pistons and reseat your valves or install hardened valve seats.
You will have to pull the transmission to replace the ring gear. While it's out you can recharge the magnets yourself and get a rebuilt mag coil from " Total Recoil" or R.V. Anderson.
You can make this overhaul whatever you want. You should
be able to do all except the machine work yourself. Get the books mentioned above, look them over and determine how you want to proceed. Many a Model T has been patched back together.