MTFCA Forum

My friend with the 1922 has been using a lot of oil. We pulled the head and there appears to be a fair amount of burnt oil. I've attached photos of the #1 piston soon after he bought it last summer and when we pulled the head again a couple of days ago after maybe 400 miles. Compression was 40 psi (cold). The cylinders are shiny and smooth with no scoring. My question, does replacing the rings usually help in such instances?

When was the last time the valves were adjusted? By the dry soot present on #1 exhaust valve, Not advancing timing with RPM and or running to rich which in turn causes polished/washed cylinders. Remove lower inspection cover and check with a feeler gauge piston to cylinder clearances at the lower skirt in 90 degree intervals. Might get lucky with rings but I suspect other issues will need to be addressed.

Hank

Those look like the old two-piece valves. If they are, I highly recommend replacing them before the implode inside the engine!

Keith

I have found that more oil is burned via sucking up through worn valve guides than from bad rings. T's don't have oil rings per-se anyway.

I would suspect that with this much oil (by your description) being burnt showed up more at idle as some smoke while idling and not really that much if at all while actively going somewhere.

Check what Hank suggested...but before buttoning anything up, give the valves a wiggle and maybe pull one and measure the valve guide clearance in 3 places and I'll bet you'll find a lot of wear.

I agree with Keith about the valves. Also the compression is quite low. Is it even between the cylinders? If low, you either have a valve problem or a ring problem. You can check the bore from bottom of the cylinder to the top and also across the cylinders. Also if the pistons wobble in the cylinders, they are too loose. Smooth bores indicate you are not scoring the cylinders. So you might not need to rebuild the whole engine. If it does not have a significant knock, you might get by with only rings and valves. This work can be done without removing the engine, however, if you have a 4 dip pan it is much easier to do number 4. Be sure to stagger the rings so that the gaps are not all on the same side. It is much less likely to burn oil if they are staggered. If you don't have a gauge to measure the width of the cylinders, you can take a ring and a feeler gauge. measure the gap toward the top and toward the bottom of the cylinder. The difference is then divided by pi and that would be the taper. To measure whether the cylinder is round, turn the piston 90 degrees and measure. then put a feeler gauge between the piston skirt on the side perpendicular to the wrist pin. Do this in at least two directions and measure at the same place on the piston. They should be nearly the same. Then use a hone and scuff the cylinder walls before you install the new rings. If the block has been rebored, there is usually a number stamped on top of the piston which would give you the oversize of the bore.
I would recommend you get the service manual and or the book by the club,"engine". It gives illustrated instructions on how to do this.
Norm

New Model T pistons are very cheap. Besides the condition of the cylinder bores and piston skirt wear, the condition of the piston ring grooves has a considerable bearing on compression and oil control. The fit of the piston is the bore is important, the condition of the bore is important, and the condition of the ring grooves is important. If careful measurement indicates that the cylinder bores are in good condition, they will need to be lightly honed in the proper crosshatch pattern to assure that the new rings will seat. As pointed out, the condition of the valve guides and valve stems will affect oil control as well as engine idle performance. Putting new rings in an engine with excessively worn pistons or excessive bore wear can actually make oil consumption and compression loss worse.

My engine smoked particularly at idle. Compression at 60. 5000 miles on rings, not bored. Thought the problem was loose valve guides. Stem cearance was .006 to .010 in. Reamed guides and new valves. Problem still existed.
I was making sure that the oil would gush out the upper oil valve so that everything was well oiled.
Reduced the oil level to half way between the valves and the problem went away. This oil level has been recommended quite frequently on the forum. I wish I would taken this advice a long time ago. My friend found the same thing.
Art Mirtes

In the past my engine had 40 psi compression.
Ground the valves now had 50 psi.

Later. New rings not bored. Compression at 62 psi.

Art Mirtes

No salt in a wound but your buddies engine appears to be a junkyard rebuild with a mix of parts from other worn motors. Seen way too many of them. The transmission is probably from the same family.

My machinist says "a ring job" is a patch-up for not doing the job properly. The only time he knew of a ring job working was with 60's Morris Minis which developed glazed bores using new Castrol GTX friction modified oils. These were fixed under warranty. Interestingly, the majority were fixed by squirting Bon-ami cleaning powder through the carburetor while the engine was run at fast idle. Those that didn't had to be stripped down and honed, no small task on the Mini transverse engine/gearbox unit.

Allan from down under.

In the days when labor was cheap and parts scarce/expensive, people would rework worn pistons in various ways. Shop equipment was available to recondition worn pistons, and if used with care, skill, and discretion, good results could be obtained. Those times are gone. Today, excellent Model T pistons are readily available at a very modest price, along with better rings than were available at any price back in the day. Far better valves than were originally put in Model Ts are also readily available today. Cheap gaskets may prove to be an expensive bargain, especially if gasket surfaces are in less tha perfect condition.

If an engine that has seen little use for a period of time, it sometimes happens that rings can stick in their grooves, either from rust or carbon or both. Sometimes, running an engine in that condition with clean detergent oil in it at moderate road speeds for several hundred miles will allow the rings to work loose and regain adequate function. It doesn't cost much to give it a try. Just be sure you have plenty of oil in the crankcase.

I’m with the valve guys. Didn’t do a wet test eh? That would have told you about the valves condition. Man I’ve been on here a good long while with a bit over 400 posts. About 150 of them are trying to impress the importance of doing both the dry and wet comp tests before pulling the head. 40 Lbs. cold isn’t the worst by far. In fact it’s not bad at all. But with just a dry test and the head off you’re totally guessing about what to do. 2 piece valves? Replace them. Rings? Total guess now.

Perry, Does that fall under the same rules as, "I miss my ex-wife but....., my aim is getting better",? Asking for a friend.

Hank

Thank you for your comments....great info that we'll digest and apply to our situation.

The car had sat for over ten years when my friend bought it.The fellow who rebuilt it died. His son-in-law knew nothing of it's history when we picked it up but the attention to detail in many areas shows some care....we just don't know about the internal condition of all the mechanicals. I suspect this is a problem faced by many people buying a T. That's one reason I've documented everything I've done to my car so the next custodian will know what he/she is getting...not that I'm planning to pass it on anytime soon.

This is my friend's first T, and he has maintained a positive "can do" attitude throughout the process so far. He got it for a good price and accepts that it may present some challenges. It has been a great learning experience for both of us and I suspect that will continue to be true.

We're going to drive about an hour to "consult" with a gentleman tomorrow who is probably the most knowledgeable antique car restorer I know....he makes his living working not just on Model T's but on some really rare and expensive vehicles. Between your comments and what our friend has to say we'll plan our way forward. Hopefully this winter we'll get my friend's car in shape for a good touring season in 2022.

Happy Thanksgiving!

OK then.., Interesting!

A car that sat for ten years could definitely have stuck rings. If that was my car, assuming it is in roadable shape and free of knocks or other indications of serious engine problems, aside from oil consumption, I'd put fresh, high quality oil in it, such as Rotella 15/40 for diesel service, which has a high detergent/dispersant level, and drive it out on the road at up to 30-35 MPH for a few hundred miles. I'd also use Marvel Mystery Oil as directed in the fuel tank. Check the oil level and condition frequently. Add oil as needed to keep the level about halfway between the gauge cocks. If the oil becomes thick and dirty, change it. The engine may free up and run well with minimal oil consumption after some road miles. If not, no harm done, and you'll have had a good chance to assess the overall condition of the car in actual service, and you'll have had the pleasure of driving it without the up-front investment of considerable money and effort. Have your friend advise you as to how to use the spark and mixture controls to the best advantage to avoid any unnecessary soot or carbon deposition. Perform carburetor repairs and ignition system repairs as needed. Clean plugs as necessary to prevent misfiring.

The purpose of meeting with our friend who restores antiques cars for a living was to get his opinion on how best to approach the work. Having worked on hundreds of Model T's he has the knowledge and tools to do pretty much any work that needs to be done and lives close enough that we can take advantage of his services. It was important to get him on board because we will need his help to do some of the work that we might not feel comfortable doing (or have the tools to do.) He's a busy guy so we wanted to be sure he'd be willing and able to help us.

Pat - My friend has put about 500 miles on the car using Rotella 15W40. I think he's also used some Seafoam. There are some other things going on with the mechanicals that I didn't mention in the original post that also need to be addressed. For example, at first the car ran best on Mag, now it runs best on battery....changing the mag post and cleaning / adusting the timer, re-wooding the coil box, repairing the switch and having professionally rebuilt coils hasn't helped. We borrowed a Magneto tester and the output is way below optimal (see photo.) We read and re-read the posts in this thread and where possible investigated the suggestions so we would have some useful information to share during our discussion. Yes, there was too much oil in the crankcase - yes, the intake valves were two-piece, yes, the valves were sloppy in their guides, etc. etc. etc. Thanks again for all the input. After a thoughtful discussion we came away convinced the best course of action is to pull the engine, disassemble and overhaul it. There are just too many issues to address to try "band-aid" fixes and we just don't know what's going on inside the engine and transmission.

Neither my friend or I have a long history with Model T's - I never did any work on a car before 2011 (Army Jeep) although I've tinkered on airplanes since 1975. We don't have the breadth of knowledge or experience possessed by many members of this forum which is why I ask questions.....lots of questions. I do read carefully everything you are willing to share and do my own research to boot. My background is in science (34 years teaching biology and chemistry) and collecting and analyzing data is my thing. As I've said before, this forum is an outstanding source of information on Model T's.....I don't know how I could have restored my car without your help so thank you.

Hank, something I've said or done has obviously offended you and for that I am sorry. I hold you in high regard and have quoted you many time to others because of the great info you've shared with me in the past. Some of your parts are on my car. I am just trying to enjoy the Model T hobby and to help others as I have been helped but being new, maybe I unintentionally crossed some boundaries. Perhaps I post too much....

It sounds like you have covered the bases and given the car a good shakedown. It looks like a general overhaul is the next step for the powerplant. Vlaves and oil burning aside, and while not an absolute necessity, a good mag is a good thing to have. I like having the option of using the starter, or "starting on the spark", or hand cranking on either Mag or Batt. Pushing or pulling the car is yet another option in case of a low or dead battery, or no battery at all, or just taking advantage of having parked on a hill.