This is not just normal Model T noise. In fact, it's no extra noise at all. Not a knock, or a rattle, or a ding. It's a pretty high frequency vibration I can feel through the steering wheel and floorboards. I was planning to drive this runabout to the OCF, but now I'm having second and third thoughts.
After looking at some previous discussions on the subject I've tried different coils and found no difference. The pan ears are fine, and the blocks are in place. The front mount is solid. Those are the only things I've checked so far.
This engine has only about 3000 miles on it since it was apart at Mike Bender's for replacement of a bad valve lifter. My guess is about 5000 miles since a complete rebuild in 2013.
Is this vibration when the engine is rev'd up only or when the car is in motion?
When I first noticed it I thought "U-joint?", but the vibration is the same at fast idle as when it's moving. It's not anything from the clutch on back.
What did you replace in the rear end?
Axle shafts, big felts on one side, seals, and DS bushing. As I said, that's all irrelevant. The vibration is present when the car is sitting dead still at fast idle.
Can you locate the vibrations point or points?
Seems if from the seat you feel vibrations from the steering wheel rim and floorboards, those parts are connected to the body via dash and main sill. Maybe the body bolts or firewall brackets are loose?
Can you put a clear container of water on the engine somewhere and see it shake, then move it to top of cowl, and then to floorboards and compare the visible shake in fluid motions?
May not work, but thinking a try might find the source.
Triple gears? Cam gear? Sure hope you get the car to OCF, Good Luck, drive careful! jb
I would love it if this was something as simple as loose body bolts. But it's present when the car isn't moving. I think that puts loose body bolts in the same category as the rear axle.
Steve, Does it still vibrate when in low or reverse?
How's the magneto?
Fan blades making contact with anything?
Steve, maybe your spark plugs are acting up, bet you could make one of these fixtures so on the road to the OCF you can fix 'em
If the vibration wasn't present before you swapped rear axles, then I would sure look at things that changed when you swapped the rear axle. Did you use a different U-joint? Did it slide easily into place, or was it binding and have to be driven in? Did the 4th main position get disturbed during the swap? etc.
My dad always complained about a thumbing vibration after he had the engine rebuilt. He never was able to find it. I never heard it unless in the passenger seat. Finally found the cause by accident when I was polishing the Pass. front fender with an orbital polisher. Re tightened all the fender bolts and it went away.
How could it be the U-joint or anything behind it? The vibration is present with the car sitting perfectly still with none of those things moving.
Dan's suggestion of spark plugs is an interesting coincidence. I did find and replace a bad plug this morning. Unfortunately it had no effect on the vibration.
Loose flywheel or loose timing gear?
Steve, Does it still vibrate when in low or reverse? Does it vibrate in high gear? If it stops in any of those it would help narrow down the cause.
This is your first major trip in the T. I bet you are just like most that have taken off as you plan to. Seen it happen many time when we have took off on a 3,500 to 6,000 mile drive. You will feel and hear more things that have always been there and are not a problem. My advice is "Run it and see what develops".
Have fun on your trip
Oops, my bad Steve, I missed the part where you said it happened even when the car wasn't moving.
Did you install anything new up in the engine compartment, like maybe engine pans that weren't on there before? Did you find something that runs from the engine to the frame loose and tighten it?
From your description, it almost sounds like something is transmitting normal engine vibration into the rest of the car that wasn't before. Hope you either find it or determine that it isn't a problem after all.
I think Harold may have nailed it. Sometimes people donít safety wire the flywheel bolts correctly and they can loosen over time. You might be able to access them through the dip tray to inspect, but probably you will have to remove the engine to tighten and wire properly
Being high frequency and inaudible, combined with a recent replacement of a lifter, I'd place my money on cam nut coming loose on timing gear causing gear mesh trouble.
I could be completely wrong, but I think that a loose flywheel is going to give a lower frequency knock if really loose (and you'd sure hear it). With dowel pins and safety wire, even incorrectly installed, the bolts won't move much and the dowel pins will keep things in place such that a vibration is unlikely to develop, much less a high frequency vibration.
What about your forth main bearing, you had your rear axle off and put it back on. How did you align and tighten the joint? Can that ball cup be a little off kilter?
Several have mentioned body bolts. I would start there. The engine puts out a lot of vibration and is solidly mounted to the frame. First start with the engine mounting bolts on the side of the hogs head. The ones through the the wood should be snug not tight. Do they have cotter keys? You already mentioned that you checked the front mount. Next look for loose bolts in the fenders as George talked about. These are simple things and easy to fix before diving into the engine. If you cannot find anything by checking these things then start with the simple engine things first, such as the cam gear, front pulley, fan bearing, etc. Or do as Mike Bender suggested, drive it around for a while. Do short trips first then longer ones.
I had a strange noise when turning after I rebuilt my engine. Turns out it was the fan hitting the starting crank ratchet in the front of the engine. A longer fan belt solved the issue.
Fan blade, belt, bushings or pulleys vibrating.
coils out of adjustment causing one or more to fire at different timing or problem with timer.
compression varies from cylinder to cylinder.
Something in the engine or transmission out of balance.
If you have checked out all of the above, and I would caution you to be sure the fan blades are not loose or cracked which could damage the hood or radiator.
I would say if your drive is a short distance, go for it. If longer trailer the car, or go as a group with a trouble trailer following. If the vibration continues to increase, trailer the car. If it remains the same, have fun and drive.
I have experienced similar feelings often, when leaving home in a truck, it feels shaky, but when you reach your destination, it's good, and feels better on the way home. Runnin' smooth, perfect. Dave in Bellingham, WA
Joe, I held the U-joint shaft level with a piece of wire and slid it into place without much trouble. The ball cap was and is stuck to the pan with Ultra Black, so it's not going anywhere.
After dinner this evening I went for a ten mile drive that included a climb up Horseshoe Hill in high gear. I'll continue to check various suggestions this week and I'll continue driving the car. If I find something, fine. If I don't and the car is no worse, I'll go and see what happens.
Sounds like a good plan. Just check what might be different from reassembly. Iím doing the same thing with my 1920 Roadster after a long block rebuild. I also restored the rear end, new thrust washers, etc. so far so good.
Check your magnets/keepers.
Ken in Texas
it may help to use a stethoscope at different spots on the engine when running, should to pin point where the source of the vibration.
Take the fan belt off and try it. I've had a very out-of-balance fan blade make a LOT of vibration.
Steve, Did you change out your 1915 roadster steering gear with the 1915 steering gear that you were rebuilding ? I would check out that all the steering gear mounting bolts are tight, etc. Also check that the carb rod lever arm and timer rod lever arm are pinned tight on their rods. I think 1915 still used the two pin lever arms, did you use two pins and one fell out?. I'll bet that a loose carb rod and arm can vibrate at a high pitch.
Well Steve! Whats your progress? Is the Trip in the T still on? Just curious.
Still up in the air. Somebody who knows what he's doing will check it out tomorrow.
Experienced T mechanic checked it out and drove it. Suggested improvements to my spark practices. He said go. I'm packing.
Great news Steve. Looking forward to seeing you there.