I have gotten a long stored TT running, new carb, fuel tank reworked, new line, filter. New rebuilt ignition (John D for referral), new wiring harness, coil boxes from a rebuilder here, lots of little goodies. Short block was untouched. Replaced head due to a crack in the outer jacket, new gasket, bolts, torqued 50lbs.
Problem is that its not running smoothly, it sure sounds like its running on 3 cyl. pum-pum-PUM - pause - pum-pum-PUM - pause - pum-pum-PUM - pause. You get the idea.
I used a temp gauge to shoot the exhaust manifold and the #1 cyl was about 80 or so degrees cooler than others. I checked the coils and visually they all seem to be sparking the contacts moving as the car idles.
I am wondering about compression and spark. The timer was cleaned up a lot and new wires, but perhaps one of the connections is not up to snuff. I read a post (I did search on this) about testing with an electric fence checker which I have ordered. I have a compression checker but have to see if it has large enough adapters for those massive holes in the head.
Also, this is my first TT and we got it running and drove it some - barely - it runs super low. Has a 2 speed box on it from prior owner. One gear is super low like a stump puller, the other is a little high for starting off but goes OK. I have yet to figure out the second gear but have to rewatch that youtube video. I guess if I push the hand brake forward I can then when release the forward pedal, high gear will engage?
Reverse makes a noise that is not very nice sounding but it works. Perhaps the linings are worn out on that?
I would like to get it all going. I will take a video of the engine just for kicks and you can see what its doing or not doing.
You folks are great. Cheers, and Happy New Year!
Easy first test is swap the number one coil with one of the other three and see if the cool cylinder follows that coil or stays at number one.
first do chris's test, you need all 4 cyl. shes only 20 hp and you want all of em. most aux transmissions are three speeds, under drive, direct, and over drive. you would move the shifter side ways to get one of em like shifting a normal car, what brand is it? and certainly you need to understand how to drive it! as in, yes all the way forward with the brake lever is high gear. theres alot more to driving a model t than i wish to type here, but its all here on the web somwhere. no one there to help?
Hey, I checked compression in the engine and seems #3 is zero, others struggle to hit 25lbs but the tester I have is a good one but the large pipe thread plug holes problematic. I have a large rubber stopper style plug for the tester, but I can hear air escaping except on #3 where its not doing much of anything. The cylinders all looked good and no grooves or wear, but thinking a valve must be stuck. Doh! Wish I had rotated the engine with the dang head off.
I only drove it a short distance on a long driveway, its first motion in many many moons, was a museum truck on display before it was bought and had oil in it, but the carb was broken and coil boxes mostly for show as few of them worked. The engine has always turned over nicely, was not frozen. Wonder if I can get valve working or if the engine needs to be torn down. Have to do some reading I can tell.
The rear transmission is a Warford and is a two speed with a neutral.
You can look through the spark plug hole with a flashlight to see if the valves are both opening and closing.
do like royce said, find the ones that are stuck and soak them with your favorite schmoo. then with a brass drift gently tap them down, then turn the motor to get them up, then tap them down....untill you're blue in the face. often you can get them free, and once running the heat and vibration may bring it back to life. a little oil in the cyls will bring up compression temporarily, and again, running is good for it. i have several warfords and they are all 3 speed. did they make a 2 speed? dont know. look at the ends of the cover, if there are 2 shafts going thru the shifter, you have 2"gates" for the shift lever to enter, meaning when in neutral you should be able to go sideways into the other gate. its a normal H pattern, but 3 speeds. got good coils? have fun
If one of the valves is stuck open you can tap on it with a stick and hammer to close it. Assure the piston is top dead center on compression before tapping. One time may do it or you may have to repeat with oil around the stem each time. I have done this on more than one occasion Dave
This maybe another newbie question, but I have used a borescope to look inside and cranked the engine and it seems like only the rear valves open on all cylinders. Is this a "suck valve" - intake sort of engine? I have looked at the shop manual and see they do have springs and cam but nothing describing the engine at least the part I am looking at. Hmm...
I believe I would take the head off and carefully check all the valves and unstick them as necessary.
When the head was off at the beginning of getting things going again that would have been the time to do it.
When you have the head off check the valves if they are the original ones. Originals had 2 holes in them on the top of the valve.
Most T guys replace them with new ones which are readily available.
The valves are opened by the camshaft acting on the pushrods which act on the valves. The intakes and exhausts are opened all in the same manner.
I don't know why you need a borescope, the valves can be seen with a flashlight looking thru the spark plug hole.
Take the valve cover off. Its got two nuts. Then look while the engine is turning over. You will likely see the problem.
Clayton, thanks. It maybe 3 speed, I have no idea but have to try it. Its all new to me. Yea, maybe running would loosen it up with the fresh oil we put in it. I can hope. Or have to remove head and get into it again.
I have loaded a video of the valves on youtube.
You shouldn't have to pull the head at least not yet.
As Royce mentioned remove the valve cover on the side of the engine beneath the manifolds and check the valve action. Likely you have sticking intakes from the look of the video. You will be able to see clearly if they are stuck or moving slow with gummed up stems. Also check your valve clearance while at it. It may have adjustable tappets if so you may be in luck if you need to adjust.
BTW if you don't have the Model T Ford Manual/Service Guide get a copy it will explain a lot!
Thanks guys. I did try looking into the combustion chambers with a light but was unable to see, perhaps if I turned out all the shop lights my eyes would work better looking into that dark hole and seeing anything. I have a borescope which comes in handy for some stuff and used it.
I have removed the side cover and watched the actuation of the valve train with the cam. The cam is not wiped out and its showing normal movement. I am fixing to check (southern terminology) the clearances. I have the service manual and was reading about grinding valve seats, it shows a desired seat, explains how to rotate a valve but not how to round off the head seat so it has the small contact area preferred. That was odd omission, but anyway. getting into it. I read that some of these valves were made in pieces, is that a possible problem here?
Yes the original two piece valves have been known to "lose their heads" and do major damage. Do a Forum search to see more..... If you take her down for a valve job I would strongly suggest all new modern one piece valves and check the valve spring retainers and pins also. They wear out, pins have been known to get bent. I did a valve job on my '27 last spring and she was like a new car, amazing what a little compression can do!
OK I am catching mistakes (DOH!) I must have mis-aimed the borescope (easy to do, they are actually a PITA sometimes) and all the valves are working, I was really wondering how in the world I was not getting valves opening. I must have shot video of the head to block area that looked like a valve. I checked the clearances and amazingly they are within spec. But its possible that one valve has carbon build up the stem or seat on #3 not sealing it up. Have to do more tinkering.
Yes, Larry, as easy as it is to do work on a T I may was well tear the head off and rework all the valves, putting in new hardware. Thanks for advice. I can hear air coming out when I tried another compression test on #3. Pays to turn the radio off sometimes LOL.
Before I would jump to the conclusion that I had a compression problem I would check the timer for wear and or dirt. I find the biggest cause to misses is the timer for several reasons. Just thinking!! Dick C.
Dick, thanks for your comment, however I did a compression test and the #3 had zero. No that I have all the radio and noise off in the shop I can hear air escaping from #3 through a valve during compression testing, so I am nearly 100% sure its a valve sealing issue of some sort.
one T I bought years ago had similar issues, I pulled the plugs and the side cover and sprayed the guides and springs with some penetrating oil , lo and behold the valves seated and she started right up .
Just because it was in a museum does not mean it was dry, I suspect there was some internal rust on the guides, especially one in the up position and on its seat.
Another big car I bought also ran unevenly , all it was was rusted valve springs on a couple valves, after sitting in a Museum for 30 yrs. They looked ok, but failed a spring test due to rust.
If my quick cure doesn't do it, off with the head. just pull em out, light grind , replace the springs and back together . then
test the compression . if you have to reset the clearance, use the KR Wilson measurement method,,it will give the best power. Make sure block has not been resurfaced as this will affect the measurements .You can use a high quality carpenters sliding bevel square for this .
A little caution make sure your handbrake will stay in the park portion , some folks use a door hinge on the floorboard, I take a rope with a marine lifeline pelican hook and latch that around the lever, the rope is securely fastened to the seat riser at the level of the brake handle.