no starting: no compression

[NY John T]

Hi,
I tried for awhile (when I got the time) to try to start a 21 engine. It won't start. I had the coils rebuilt properly, I rebuilt the Holley NH, the starter slowly cranks over the engine, but it still won't start. I took each plug out and looked inside and all looks very clean with possibly replacement valves. I did a compression test and here's what I got:
#1 cylinder-29/30 psi.
#2 cylinder-zero psi.
#3 cylinder-10 psi
#4 cylinder-25 psi
Would this indicate that the valves need to be adjusted or is it a problem with rings? I'm not familiar with the internals of the T engine.
Thanks so much,
John

[Humblej]

Compression numbers so low makes me think the valves are stuck or not seating, could be a lot of carbon on the stems, faces, and seats. A starter that cannot crank at a good speed with that poor compression is no good, time for a rebuild or replacement.

[Bruce Compton]

Not surprised at the low readings if your starter is turning the motor over very slow. Check the battery, battery ground connection, the size of cable to starter and the connections from the battery to the switch and to the starter. Then try injecting a few squirts of oil into each cylinder. I suspect you have a stuck valve on the "zero" cylinder as well.

[TXGOAT2]

Do you have a really good 6 volt battery in the car? A good battery and proper cables in good condition should spin that engine very fast, and if it is getting any spark and fuel, it should kick, and probably ought to start and run, if poorly.

A weak battery and/or a dragging starter may prevent the ignition system from working.


The engine won't run if the carburetor adjustment is turned all the way shut.

The engine isn't likely to start if the ignition timing is too late.

You should be able to hear coils buzzing and get a good hot blue spark from each plug wire as the engine is cranking with the ignition on BAT. The car may not start with the ingition switched to MAG.

Choking the carburetor for 3-4 seconds with the engine cranking should cause it to flood and drip gasoline out on the ground.

[Jacob Mangold]

Not sure about your compression issue but for you starter troubles, get a wire brush or a battery post brush tool and clean your connections. Also make sure that you have a good ground. Sometimes when I let my T sit without the battery connected to the wires, it won’t turn over initially but once the connections are cleaned, it turns over normally.

[NY John T]

Starter running slowly and getting hot when I was trying a lot yesterday. Battery was very low so I put it on a charger previous night, but it was not up to full. I'll check all connections. Starter may need new brushes; I'll check that.
If it's valves, do any of you recommend pulling the head to adjust valves? I've never opened up a T engine.
Thanks for the suggestions.
John

[Oldav8tor]

After you've cranked the engine over a bit, does the battery terminal on the starter get hot (careful!) If it does, it may be the internal connection within the starter is poor, resulting in a high resistance.

Repairing a Common Model T Starter Problem.pdf

(958.95 KiB) Downloaded 85 times

[TXGOAT2]

As noted above, clean, tight connections are important. Battery and starter cable connections should not get hot when cranking the engine. Have you tried cranking the engine by hand with the ignition off?
If you don't get any kind of kick, pop, or other indication of firing when cranking the engine, it may indicate that you have either no spark or no fuel.

If the engine cranks easily on the starter with the ignition switched OFF, it indicates that the timing is way too early or the firing order is wrong. Plug wires must be in the correct order and the wires connecting the coil box to the timer must be in the correct order.

[TXGOAT2]

Don't crank the engine with the starter for more than 20 seconds or so, or it will overheat. Crank for 20 seconds or so, then allow it a minute or two to cool off.

Your clutch may be dragging due to being out of adjustment. That will make the engine hard to crank.

Model Ts do not like thick oil in the crankcase. 10W30 is a good choice. Thick oil or very dirty oil will cause the clutch to drag and make starting difficult.

[Russ T Fender]

Jack up a rear wheel and block the front wheels. That will reduce the drag and help the starter. As was mentioned before try squirting a bit of oil in each cylinder, replace the plugs and try again. Are you sure you are getting gas? You might also try to remove the plugs and drip a little gas in each cylinder. If it kicks over and dies you're not getting fuel.

[Craig Leach]

Had a very simular issue with a freinds 1917. He asked me to look at it because when he tried to start it. It would move foreward. He had gone
through some health issues and the car had not run in almost a year. Figured the clutch plates were stuck. I jacked the rear end up and placed
it on jack stands to start it. Suprise will not start. Went through all the checks. Spark, fuel, compreession. # 1, 2, &3 had no compression. Zero.
Found the exhaust valves stuck (In this case all the way open) 3 hours of lube push, lube pry, lube push again and the valves freed up. engine
started after a lot of smoke ran fine. Started easy with hand crank afterwards. Not sure if this helps but thats what my last experience was.
Craig.

[Norman Kling]

What is the history of the T? How did it run when parked, and how long was it parked?Did you buy the car as is, and why was it parked? Many different things can cause a situation like you have. It is just guessing to offer answers to what information you have given us.
I strongly suspect that the valve in cylinder 2 is stuck. This can happen by a little water leaking into the cylinder while parked a long time which could cause the valve guide to rust, or it could be carbon causing it or even a weak spring or keeper come off. You do not need to take off the head to adjust the valves if it has adjustable valves lifters. The originals were ground to fit and need to remove the valves and grind the stems to fit. However that would not cause a valve to lose compression unless there is zero clearance. Some oil down each spark plug hole and cranking around a bit should oil up the rings and raise the compression if the cylinders are dry. It should turn easier if you jack up one rear wheel If the car was parked for a long time with the parking brake on, oil can get thick between the clutch plates and cause hard starting. One way you might get it to start the first time would be to pull the car with a tow strap connected to the frame or to the spring right next to the shackle. Do not pull the car with a strap to the axle because it can often bend the axle.
If I lived closer, I could look at your car.
Norm

[Charlie B in N.J.]

Want to tell exactly why the engine has low compression? It’s really simple. You did a dry comp test now do a wet one. A couple of shots of oil into the cylinder the check compression in that cylinder. If it goes up it’s rings if it doesn’t it’s usually valves. Now you know what’s wrong. No speculation or guesses or try this or that. Valves? Pull the head and get to work. No guessing. Rings of course are a bigger problem. This is probably the twentieth time I’ve posted this here. You don’t want to guess. You want to properly diagnose a problem to save time and money and get your car going.

[Jacob Mangold]

Starter running slowly and getting hot when I was trying a lot yesterday. Battery was very low so I put it on a charger previous night, but it was not up to full. I'll check all connections. Starter may need new brushes; I'll check that.
If it's valves, do any of you recommend pulling the head to adjust valves? I've never opened up a T engine.
Thanks for the suggestions.
John

That’s what happened to my starter. It would just click and barely spin. It would get very hot as well. Took the starter apart and the starter field coils were very damaged. I ended up buying a new one from langs. It might be a good idea to take apart your starter and see.

Good Luck, Jacob Mangold

[JTT3]

John, before you take the valve cover off you may consider when you do a compression test to be sure the throttle flap is fully open. You would do yourself a favor if you remove all the spark plugs when testing. As others have said, a squirt of oil in each cylinder will be a benefit. You may also want to have a jumper cable going from the negative post on one end and the other end connected to one of the starter bolts to insure you have a good ground. In addition if you haven’t recondition the foot starter button assembly it also could be something to do to help with stronger overall volts/amps . If the starter works better it will tell you your regular ground connection is not a good one. Just the way I’d do it but I’m probably wrong. Others may have some better ideas or methods.

[Charlie B in N.J.]

About that starter business: I had a slow cranker too. It wasn’t until I saw that braided ground strap smoking that I found the problem.

[NY John T]

Thank you all so much! so many great ideas to check. I'm going to borrow my son's borescope to check all the valves one at a time. That should be the easiest way to see a stuck valve.
Next I'll put some oil in each cylinder to see what that does.
Both wheels are up off the ground slightly, they can move but drag on the ground slightly. Would this do anything?
I bought the car 2 years ago and it sat. Inside the cylinders look very clean, but can't tell what the guides look like.
I'll change the battery with one that I know works well and check all the connections.
I put about a gallon of gas in the tank which is newly sealed but was dry. Maybe I need more gas(?)
I can only work on the car on weekends, so this will be a slow process, but I will report back.
Where would we be without this great forum????
Thanks again,
John

[Scott_Conger]

I love borescopes, but you don't need one to see a valve...a flashlight and eyeball looking through the spark plug hole is all you need.

regarding valve movement, the easiest thing to do to watch while cranking engine over is to pull the valve covers off. On your "dead" cylinder you'll probably find one valve stuck full open and if so, you can put a couple pennies on top of the push rod/lifter and "overlift" the stuck valve and with oil, eventually get it moving again.

After you've squirted oil into the cylinders to get wet compression, focus a lot of penetrating oil onto/into the valve guides from the sparkplug hole and let everything sit 'til next weekend.

[DaveBarker]

John - regarding fuel level, if it were me, I'd want to be sure to have plenty of gas in the tank to insure fuel flow to the carb (I'd probably have half a tank to be sure, but that's me). Easy way to test fuel flow; with a can under it, open the drain valve on the bottom of the bowel on the carb and see what comes out.

[NY John T]

To all,
Here is a shot of the number 1 cylinder.

The others are similar. It looks pretty clean. Can you tell anything from looking at it?
Tomorrow I'll try a compression test with some Kroil that I shot into each cylinder, and also see if I can see a valve that is stuck.
Thanks,
John

[Scott_Conger]

Kroil is going to be good to free up valves, but it isn't going to seal the rings like a shot of motor oil will, so for your compression check, plan on motor oil...

orient the pistons 1/2 way down the cylinders and give a few really liberal shots of motor oil DOWN THE CYLINDER on all four, and wait a minute...now you can do compression tests again and see if any come up (some will). That will be the wet test to compare to the dry test.

[JTT3]

To add to Scott’s reminder on oil, don’t forget to have the throttle wide open and all the spark plugs out so you get a more robust spin to test each cylinder.

[Norman Kling]

Another test which can be used is a blow down test. You take an old spark plug and remove all the porcelane and fit a tire valve in the hole. Then put the plug in and with the piston at top dead center at the same point that the spark plug would fire, put compressed air into the valve. If air comes out the intake, your intake valve is leaking and if out the exhaust, the exhaust valve is leaking. This leak can be either a stuck valve or a very burnt valve which leaks. If air comes out the oil filler hole, your leak is from the rings.
One more thing can happen. you could have a blown head gasket between 2 cylinders. However, it would affect compression on two adjacent cylinders. Usually 1 and 2 or 3 and 4.
Norm

[NY John T]

Yesterday I took off the two valve covers and discovered why cylinder #2 had no compression. Both valves were stuck open. See photo. I believe the engine was rebuilt (all looks new and clean) but I noticed a tiny speck of rust inside the cylinder. I put a bunch of Kroil in each cylinder and got one of the valves moving, but the exhaust of #2 wouldn't budge. Reluctantly I tapped the valve from above and got it to move, but it kept hanging up until I work it for about an hour. Now all valves are moving. Valves look bent, but that's only the perspective of the lens.
There are no nuts to adjust these valves; and I got readings of about .025. Is this OK?
Other things: I raised one wheel and still it's hard to hand crank. Should I raise both wheels? I think so.
Battery looks dead (on a charger over a day or two. Oil in engine looks clean; so I'm thinking the engine was never run, but just sat for a couple of years. I took the starter out to replace brushes, so that will work better. Cables are all new from vendors. I will clean contacts to make sure power gets through.
Is it possible to get a better free neutral that will allow engine to crank over better? I've not looked into the differential to see what its condition is.
Thanks all for your support.
John

[Scott_Conger]

Since this is a total unknown to you, I'd be inclined to jack up the rear and block front wheels...put transmission into neutral (but not with brakes) and allow the rear wheels to become a flywheel for you. This will reduce strain on starter and aid in getting the car started since the natural drag in the transmission will be relieved by transmitting that reluctance to the (rotating) wheels.

I'd also flood the valves through the plug holes as I mentioned earlier and now that you have the covers off, I'd flood the stems, too. You can also lift those valves more, to break stiction in the guides and give the Kroil a path in.

[NY John T]

Thanks Scott. I'll do that with the oil, and jack up the other rear wheel. Also want to try to get a free neutral. Have to research that.
John

[Steve Jelf]

Model T doesn't have a total neutral. It always wants to creep. Fortunately, when the car is warmed up the creepiness is too weak to move the car. Starting cold, it may actually move. That's why the front wheels should be chocked during a cold start. Also, with cold oil "gumming up" the clutch it may bog down the engine enough to keep it from starting. That's the reason for rear wheels up and brakes off. I've never had to raise both rear wheels, but I suppose it could happen.

A few months ago I had an interesting adventure with the creeping clutch. My runabout backs into the shop and parks headed out. One day I forgot to chock the front wheels and set the brakes. The car rolled forward and caught me by surprise. I fell over backwards as the car rolled down the ramp outside the shop, and I ended up sitting with the left front wheel pinning the leg of my overalls to the ground. I was totally unhurt. In fact I was quite comfortable. But with the idling automobile wanting to roll down the ramp, I was absolutely stuck. I had three choices. I could wait several hours for the car to run out of gas and die. I could wait for the engine idling fully retarded to overheat and die. Not caring for either of those options, I phoned the 911 dispatcher and asked for a deputy to stop by the place and shut off the engine for me. I stressed emphatically that I was not hurt, not in danger of being hurt, and only needed somebody to shut off the engine. So of course a team of EMT's with an ambulance and half the fire department showed up along with the deputy. He shut off the engine, I got up, and we rolled the car back into the shop. My only "injury" was embarrassment at doing something so foolish. So far that has caused me to pay more attention to my starting procedure.

[Craig Leach]

Hi Steve,
That sounds like a no laughing matter but doesn't matter if you laugh story. Thanks for sharing and the reminder to chock the wheels.
Craig.

[Adam]

I ended up sitting with the left front wheel pinning the leg of my overalls to the ground. I was totally unhurt. In fact I was quite comfortable. But with the idling automobile wanting to roll down the ramp, I was absolutely stuck. I had three choices. I could wait several hours for the car to run out of gas and die. I could wait for the engine idling fully retarded to overheat and die. Not caring for either of those options, I phoned the 911 dispatcher and...

Maybe you had four choices? Could you reach the choke pull on the front of the radiator?

Just as an FYI, that NOBODY really thinks about as an option; Anytime you are hand-cranking, you do have an “out” if things start to go wrong. Pull out the choke to kill the engine. Bear in mind It makes them hard to re-start, but anyone with a T should know how to deal with a flooded engine.

[Steve Jelf]

Hmmm... Good question. I just went down to the shop and checked, and yes, I could have reached the choke wire. It's unlikely I'll ever again get into a similar fix, but it's good to know the option is available.

[Scott_Conger]

Adam

you have really hit on a safety point!! The choke trick is something EVERYONE should know about.

My barn is pretty well packed in my storage area and 2 winters ago, I was hand cranking a car that was 90 degrees to, and 4 feet away from another T. At 30F, I got the car started and it rapidly closed the 4' gap with me pressed against a running board behind and a radiator in front! As it was a T under restoration, there was no choke wire and no hood (thankfully). I had to strain forward to grab the bellcrank and flood the car just as you stated. I was most fortunate to take the one split-second of time to think to straddle the crank and not allow it to re-engage with the engine with fearful results just prior to becoming pinned.

It really cannot be stressed enough that a T is sufficiently blocked/chocked prior to starting...and I KNEW BETTER, having been chased out of my garage and 1/2 way into the alley of my former home by my first T...and all this having spent my teen and young adult years around my father's T's. Some people are really slow learners and I must admit that I am one of them in this instance.

Steve

absent the awareness of the choke, you are most fortunate to have had a phone handy

[Jacob Mangold]

This is the reason I like having an auxiliary transmission on my TT. I can get a true neutral every time with an auxiliary transmission which eliminated the sticky clutch problem. Either way, I’m sure to chock the front wheels every time I start it, just to be sure.