My "rebuilt" engine won't turn over: what's the cause?

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Model T Ford Forum: Forum 2013: My "rebuilt" engine won't turn over: what's the cause?
Top of pagePrevious messageNext messageBottom of page Link to this message  By Matthew Atchinson on Saturday, November 16, 2013 - 06:07 pm:

This summer I put my engine back in the chassis. I just have to get the bands on properly now. When the president of our club helped me with it, we discovered before putting the pan on that the engine will simply not turn over. We disconnected all the pistons: and one at a time hooked them up to check and see if the engine would rotate. It did for every piston. It even rotates with any given three of the four attached and one not. But when all four are attached it simply can not be cranked by hand. Do you guys know what could be causing this? It was a cheap job done by myself and my club, and we managed to save 90% of the original parts.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Bishop, San Diego on Saturday, November 16, 2013 - 06:43 pm:

Matt,
I'm by no means an expert on engine rebuilding, but I just had a fellow club member help me rebuild my '17 engine. I was told by several people that it would be tight when finished, and wouldn't be able to be cranked until broken in (no starter). Sure enough, he had to tow me several times to start the car because it was too tight to crank. Each time it got a little looser to crank, until finally I was able to crank start it.
Altho I thought maybe it was because of the new babbitt, reground crank, new cam shaft, etc, I was told it was mainly because of the new rings which have to settle in. While it was tight, the radiator also got a little hot sooner, but as he tow started the car and I drove it more that went away.
Hope that's correct and helps. I'm sure more knowledgeable people will chime in if I'm wrong.
Good luck.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bill dugger on Saturday, November 16, 2013 - 06:56 pm:

Matthew:
Here is myIMHOpinion, try this for size.
Remove the 4 spark plugs, squirt in some (oil, not a lot and let i stand for say 30 minutes and then try to crank the engine (NO PLUGS) the see if it will turn over, and if it does try it with the plugs, but if it is still tight try towing it! Hope you have good brakes.
My '19 engine sat for a good spell and I would hand crank it once in a while. When it came time to start it "NO GO". However it was my coils did not have the amps needed.
Now it, once in a while give me a free start., and fun to drive.
Take care and go out and enjoy the ride in a "MODEL T"
Bill d


Top of pagePrevious messageNext messageBottom of page Link to this message  By keith g barrier on Saturday, November 16, 2013 - 07:22 pm:

To tight, better add some shims, should never be that tight. When I build mine I can spin the crank by hand before the rods are installed, then just the usual drag from new pistons and rings. I expect it to start by hand cranking if I want to do it that way. In my opinion if you have to tow it with the plugs out, it will not live long. MHO, KB


Top of pagePrevious messageNext messageBottom of page Link to this message  By mike taylor on Saturday, November 16, 2013 - 07:54 pm:

big end rod caps mismatched?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Donald Conklin on Saturday, November 16, 2013 - 08:42 pm:

If you are trying to turn it over while on a work bench or engine stand, I think you will find it much easier to turn once it's in the chassis and you are in a good position to turn the crank.

How is that for a run on sentence.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Val Soupios on Saturday, November 16, 2013 - 09:49 pm:

Check the clearance with plastigage. I usually try to get one thou clearance. That makes for a tight engine that may need to be towed the first or second time it is started but after that you should be able to crank start it. Run it for no more than 5 minutes the first time and no more than 10 minutes the second time, less time if it starts to overheat. Just to be sure check that the rods and caps were installed correctly. They should each be marked and the marks should face the cam.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Robert Scott Owens on Saturday, November 16, 2013 - 09:57 pm:

Rings will seat about the second to third time up and down. You said that any three and it will turn. Its just a close fit. Make sure it has oil and water and pull it in high gear toe a few miles. You have a good fitting motor and it will free up just fine. I did this with a fresh rebuild. The motor was warm after the three mile tow from one members house to mine. It then turned free by hand and has been a great running motor for around ten years. Good luck, Scott


Top of pagePrevious messageNext messageBottom of page Link to this message  By Joseph Geisler on Saturday, November 16, 2013 - 10:48 pm:

Even the Ford plant used large electric motors to burn them in. Plenty of water and run in of about 10 minutes on the initial start-up. I never have that problems with rebuilds on an engine with inserts. Poured Babbitt and scraping them with dykum (blueing) is different. Also using the boring bar leaves little machining marks so rebuilding the T and other Babbitt engines are different. Especially when using close tolerances. When building racing engines you purposely set them up a little loose (in SOME cases) but on a street engine for use in a passenger car they should be set up much closer. I have built several T engines and they have always ran hot and overheated a little. Do not run them hard nor for very long for the first 7-8 times after the initial start-up. What everyone here has been saying is correct too. Just don't set them up too loose or you will regret it later. The babbitt smooths out with heat and pressure unless you do not have it loose enough to easily turn the crank over when scraping them in and and hand turning the assy over while fitting the rods. I use to hook my engines up into the lathe at school and run them in while shooting oil and stopping them every 4-5 minutes and hand checking to see if any of them was getting too hot. I know that will sound silly to some of you but that was the way I did it. Even after the run-in the engine would still get hot and almost freeze up after it was in the car and I was driving it on my shake-down cruises I always do about 10 times or so after it cools completely down again. I had my 11 touring actually almost stop on its own from getting to hot initially. I was really scared as those blocks are really difficult to find (in 1975)!! After it cooled down it ran great ever afterwards. But initially I was NOT happy and I tend to be a lot cautious as I was not making BIG $$$$ teaching and with a family. Do the BEST fit up you can starting with the mains. First then last then the ctr. Then go onto the rods. Matthew it sounds like you guys did that so don't worry. If it was on the mains then I would be alarmed as the mains would need to be line reamed or checked for not being all in line on top. (one throw worn more of the three springing the crank which will break it in time.
As usual someone will say it better.
My 2c
Joe in Mo.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Richard Gould on Sunday, November 17, 2013 - 09:03 am:

If the engine turned with any three of the four pistons attached, you just need to break it in. As others have said, just run it easy and short until things loosen up. I use Timesaver on the rods and mains and avoid these issues.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Hal Davis-SE Georgia on Sunday, November 17, 2013 - 09:30 am:

I second the Time Saver. I've used it on two T engines, a hit and miss engine, and a T transmission. I am happy with them all. One of the T's was a non-electric. I started it with the crank. No towing required.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Charlie B actually in Toms River N.J. on Sunday, November 17, 2013 - 10:27 am:

If his rod & mains are too tight they should be adjusted with shims. Not a believer in timesaver.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Sunday, November 17, 2013 - 11:32 am:

I think it will be ok. If you pull it a short distance in high gear with the ignition on, it should start up. Then run for about 5 minutes. Shut off the engine and torque the head again. With an iron head, torque while hot. With aluminum head let it cool off first then torque. After the engine cools off, it should start with crank or starter. If still too tight pull again. Repeat a couple of times and it should be easier to start. Just don't over rev the engine and don't let it get too hot. As you continue to drive it should start easier and have more power. You will need to set the idle up when you first start it, but lower the idle as it breaks in. Torque again after the first few times you drive. When you get to the point it holds torque, you won't need to torque again.
Good luck.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Gene Carrothers Huntington Beach on Sunday, November 17, 2013 - 03:11 pm:

I'd never finish an engine rebuild without the use of Timesaver. It's a miracle product. Have always crank started.

No expert here though.. Just respect other experts opinions YMMV


Top of pagePrevious messageNext messageBottom of page Link to this message  By Matthew Atchinson on Monday, November 18, 2013 - 07:50 pm:

Thanks for all the responses guys. by the sound of it i'll just have to carefully pull start it. that's sort of what I figured you might say. well with any luck i'll get the trouble I've been having getting the bands lined up properly worked out, then I can seal it all up and tighten the head down and have a go at it.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Norman T. Kling on Monday, November 18, 2013 - 08:33 pm:

When you pull the car, use a long rope. Tie to the frame or the spring where it attaches to the frame. That is the least likely part to get bent. Do not tie to the axle. The axle is a weak point and can be bent or pull the ball out of the wishbone. The long rope is so that you won't run into the towing vehicle.
Norm


Top of pagePrevious messageNext messageBottom of page Link to this message  By Seth from NC on Tuesday, November 19, 2013 - 07:00 am:

Hey Matt - depending on how the back of your car is shaped, it's WAY easier/better/safer to PUSH your T with another car. That way when it does catch and fire up, you can just drive away. Especially if you are fooling with the carb settings at all, when it catches it can really surprise you. If you have a few different push vehicles to pick from, find what matches up nicely height-wise to back side of your car and then just put a furniture pad or big heavy blanket between the two.


Top of pagePrevious messageNext messageBottom of page Link to this message  By CharlesHebert on Tuesday, November 19, 2013 - 07:34 am:

Matt...if you tow to start, Place the car in neutral, press the clutch, turn on the key, choke it, and it should catch..


Top of pagePrevious messageNext messageBottom of page Link to this message  By David Menzies on Tuesday, November 19, 2013 - 09:15 am:

It is conceivable that your crankshaft is bent. With any three rods attached it is free and with the fourth attached it binds. This would be an indicator of a bent crankshaft. Standard rebuild procedures is to check for a streight shaft and rebend in a jig if necessary. Installing a bent crankshaft will only lead to premature failure. Because of the design bent and fractured crankshafts are common. Before installation they should be checked for alignment and cracks. If your engine is binding something is incorrect. Sorry if I sound like the bearer if bad news but there many instances of broken crankshafts because of a couple of thou misalignment and flexing. I hope yours is just tight Dave


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