Engine Replacement Problem

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May 21, 2002 | 07:46 PM

Lamp Doc

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Joined: May 2002

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Engine Replacement Problem

I'm at the end of the road in replacing the motor in my 1990 F150, 5.0 engine. How do I find top dead center? I thought I had it right, but I'm not getting fire in the hole. Thanks.

May 21, 2002 | 10:17 PM

Motorcraft

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Joined: Jan 2002

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From: Berlin USA

Engine Replacement Problem

IF i am not mistaken top dead center is when the number 1 cyl is up all the way. I am not sure if this is right i am just a auto tech student not a ASE man well not yet i hope this helps in some way.

May 21, 2002 | 10:29 PM

TorqueKing

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From: Atlanta, Georgia, USA

Engine Replacement Problem

hopefully, you have a timing set installed on the engine, by someone other than yourself, because if that's the case then you'll need a piston stop. If your timing cover is off, then check the dots on the cam gear, and the crank gear. they should line up, and the dot on the crank gear should be at the top, and the dot on the cam gear on the bottom. Once you've lined these up, the #1 piston is at top dead center. Now check your harmonic balancer, the pointer should point to 0, or be labeled TDC. hopefully, it's got timing marks on it, otherwise you'll need timing tape. IF it has timing marks on it, then rotate the engine until it reads the value of your initial timing, this is usually between 6-15 degrees Before TDC. Then install the distributor, with the rotor pointing directly at the #1 wirepost. Hope this helps, and as always,

Happy Wrenching,
Cadet Second Lieutenant John F. Daly III
South Carolina Corps of Cadets, The Citadel
The TorqueKing

May 21, 2002 | 10:34 PM

oldblue18

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From: Georgia

Engine Replacement Problem

[updated:LAST EDITED ON 21-May-02 AT 11:36 PM (EST)]The way my father and I always did it was to remove the #1 spark plug and have one of us hold our finger over the hole while the other turned the crankshaft with a socket and breaker bar. I think we also removed the coil wire so that we didn't crank the engine

When you feel air trying to come out of the hole then the piston is on the up stroke, and when your finger is being sucked into the hole the piston is on the down stroke(I'm sorry if this last sentence insulted your intelligence, but i though it was relivant to my directions). The trick is to get the person to stop turning the crank after all the air is pushed out but before it begins to suck it back in. This should be pretty close to TDC.

Jon
1989 F-150 XL- 4x4, 302, M50D
1995 Bronco Eddie Bauer- 351W, E40D
Finally got around to creating a gallery...check it out

Edit: doh!!! beaten by 5 minutes!

May 22, 2002 | 07:49 PM

BlueOvalRage

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Joined: Jun 2001

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From: Oxford, Indiana

Engine Replacement Problem

[updated:LAST EDITED ON 22-May-02 AT 08:51 PM (EST)]Yeah, blue, I may be a bit simple-minded, but I always use the finger in the hole trick, too. I can't say that I've ever seen anyone go to the trouble of using a piston stop. Besides, with a stop, you won't know it you're on the compression or exhaust stroke. The 'ole finger method nails it every time. I usually crank it over myself so that when I start to feel the compression, I stop and roll it carefully on around to zero on the pointer, drop the distributor pointing at number one post and then give her just a little advance before I tighten it up. Just enough to get it running and keep it running. You're going to put a timing light on it and dial it in later, anyway, right?