TDC - Turning engine
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,415
Likes: 126
From: Mequon WI
TDC - Turning engine
Working at finding TDC. I have it in neutral, I have all the plugs removed, I relieved the tension from the air conditioner and alternator. Air Pump is still tight but that turns independent of the engine. The power steering pump is still at full tension.
I can't turn the crank!!!!!!!
I have a 5/8" socket and a 12" ratchet and it wont budge. I then tried an 18" torque wrench and stopped pulling at 75 pounds. Last thing I want to do is mess up the bolt on the balancer.
Is there something else I need to do to turn the crank?
Is it really that hard to turn it? I was going to try putting a pipe extension on the wrench for greater leverage but again, afraid I might be doing damage.
I can't turn the crank!!!!!!!
I have a 5/8" socket and a 12" ratchet and it wont budge. I then tried an 18" torque wrench and stopped pulling at 75 pounds. Last thing I want to do is mess up the bolt on the balancer.
Is there something else I need to do to turn the crank?
Is it really that hard to turn it? I was going to try putting a pipe extension on the wrench for greater leverage but again, afraid I might be doing damage.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
You should never try to bar the engine over using the 7/16" NF crankshaft/damper bolt because of the danger of breaking it. Instead its best to use a remote starter push button switch to bump the engine overusing the starter.
Many years ago I ran a 12-gauge wire from the "S" terminal on my starter up to the top near my power brake booster and attached it to the fiberglass firewall using a metal screw. I can use a short jumper wire connected to my alternator HOT terminal and touch it to the metal screw to bump my engine over. Something you could easily do.
Many years ago I ran a 12-gauge wire from the "S" terminal on my starter up to the top near my power brake booster and attached it to the fiberglass firewall using a metal screw. I can use a short jumper wire connected to my alternator HOT terminal and touch it to the metal screw to bump my engine over. Something you could easily do.
Race Director
Joined: Dec 2004
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From: PARADISE
St. Jude Donor '09-'11-'12-'13-'14
There is something amiss if you can't turn your engine over with the plugs out of it. A typical new and tight engine still takes less than 25 ft. lbs. to turn with plugs out.
Better find out what else you're twisting when you are roaching that bolt in the crank snout, because it will break off. Loosen the belt on the PS as a start, but I doubt that's the issue.
Better find out what else you're twisting when you are roaching that bolt in the crank snout, because it will break off. Loosen the belt on the PS as a start, but I doubt that's the issue.
Last edited by claysmoker; Nov 21, 2015 at 09:41 PM.
Advanced
Joined: Sep 2015
Posts: 74
Likes: 6
From: oregon
I just went through this and ran a remote starter from the starter up the side of engine to driver side of car. One lead goes to "S" terminal on starter and the other lead to 12 volt terminal from battery (big bolt). This needs to be done from under car and make sure you disconnect battery while doing hookup. I also found that the motor spun to fast with plugs out and would easily run past timing mark. Reinstalling the plugs fixed that. You also need to ground high tension wire from coil to a ground the motor won't start. You tube is a good source to see how the connections are made.
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,415
Likes: 126
From: Mequon WI
Thanks for all the suggestions. The starter works just fine so that is not what is holding me up. I was planning to put a piston stop in to locate TDC. Will not use that with remote starter. Maybe I can find it using air pressure to locate compression stroke and see how close the original timing mark is.
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Safety Car
Joined: Jan 2009
Posts: 4,000
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From: New York
Pull drivers side valve cover and watch valve action on #1 cyl . Once intake valve cycles open and then closes check balancer and turn motor slightly to get your TDC on the balancer lined up.
Which valve is intake or exhaust ? Look at the intake runner , the intake valve is in line with it and the exhaust valve will be in line with the exhaust outlet into a manifold or header
Which valve is intake or exhaust ? Look at the intake runner , the intake valve is in line with it and the exhaust valve will be in line with the exhaust outlet into a manifold or header
Melting Slicks
Joined: Oct 2005
Posts: 2,056
Likes: 8
From: Redruth Cornwall
Did the same this morning!On a side note but hopefully in keeping with the OP's thread, how far in to the head should the piston stop go in order to actually make contact with the piston? I borrowed a piston stop and tried it earlier today only to find as it wasnt adjustable, the engine quite happily turned over and went past the stop!
Race Director
Joined: Apr 2000
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
With the plugs out there is absolutely no reason why you can't use the crank bolt to turn it over if the engine is not seized for one reason or another, it should turn as stated above at less than 25ft/lbs.
I don't take the plugs out when I adjust the lash on my solid roller cam and use the crank bolt to turn it over.
Is it in gear, you haven't replied about that yet ?
I don't take the plugs out when I adjust the lash on my solid roller cam and use the crank bolt to turn it over.
Is it in gear, you haven't replied about that yet ?
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,415
Likes: 126
From: Mequon WI
I am 99% sure it is in netral. 1% because you ask and I have been wrong before. I hit the starter just to make sure it wasnt locked up somehow and it was normal. As I think about it I did have the cluth depressed. I know I moved the shift lever into neutral and I did push the car but I will check again tomorrow night when I get back to it.I hope I am wrong and its that simple!
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,415
Likes: 126
From: Mequon WI
Tonight I verified it is in neutral. Turns just fine using the starter. But not with a wrench. As stated earlier, using a torque wrench I'm over 50 lbs and it will not move. I have the front end elevated to get at the pligs but I cant see where that would make any difference. I'll hook up a remote starter and find TDC that a
Way. But I'm still baffled why I cant budge it.
Thanks for all the above suggestions..
Way. But I'm still baffled why I cant budge it.
Thanks for all the above suggestions..
Race Director
Joined: Apr 2000
Posts: 17,676
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Take the starter out and remove the belts, it has to turn over (only other things are the fuel pump and distributor ). Does the starter motor sound strained or does it just spin the engine over fast with the plugs out ?
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
That is baffling. I was going to suggest same as motorhead, check the starter see if the bendix gear is constantly engaged or something. Either that or there is a bearing problem, or some weird piston issue, bout all I can think of.