351 W knocks

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May 19, 2002 | 11:34 PM

CowboyMjoh

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351 W knocks

I recently gutted my 83 f-250s stock 351 W; igniton, emmissions, computer, and replaced it with an edelbrock package, carb,cam, and intake. I got a points distributor from a 70 351 W, there was a loud knocking from the front of the engine after I started it. The stock duraspark 3 distributor shaft is an inch longer than any other 351 distributor that I can find. Could the different distributor shaft not be catching the oil pump shaft, causing the knocking? I also put a timing set in, if that has anything to do with it. I would greatly appreciate any help or insights, I am stumped with this one.

May 19, 2002 | 11:48 PM

sauerf100s

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From: Ft. Walton Bch 32547

351 W knocks

If the original distributor is an inch longer, you must be trying to use 302/289 length distributors instead. If the replacement distrbutor doesn't go down into the block the same amount as the one you took out, it will not turn the oil pump. You ran your engine with no oil pressure. I hope you didn't toast your bearings.

May 20, 2002 | 12:08 AM

CowboyMjoh

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351 W knocks

I already checked about five parts houses and had them show me many different 351 distributors for a 351 W. The duraspark 3 distributor shaft is one inch longer than ANY other 351 winsor distributor shaft out there, unless I am missing something. Yes, I made sure that the one I swapped was from a 351 windsor. It's weird.

May 20, 2002 | 12:09 AM

CowboyMjoh

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351 W knocks

Oh, also, there was good oil pressure while cranking.

May 20, 2002 | 12:22 AM

Franklin2

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From: Virginia

351 W knocks

That doesn't make much sense does it? Since you have so many friends now at the parts houses, see if the oil pump drive shaft has a different part number for duraspark III. It would have to be shorter if the dist is longer. Or maybe it just slides up in the dist farther. I would also check the fuel pump. I have never had a Ford pump make a noise, but I would guess it is possible if it was worn out, or if something didn't get put together right on front of the cam.

May 20, 2002 | 01:13 AM

CowboyMjoh

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351 W knocks

I put the eccentric on right, probably not that hard to mess up, but it could happen, fuel pumps new. I'll check them out like you suggested. Thanks.

May 20, 2002 | 07:32 AM

slikness

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From: Durham

351 W knocks

[updated:LAST EDITED ON 20-May-02 AT 08:34 AM (EST)]It might be the distributor is just catching the top of the oil pump and cranking the pump enough to give you good pressure and low rpms...my son did this on his truck (didn't seat the distributor) and as soon as it reached 2000 rpms, the pressure would drop...reset the distributor and never had a problem...

Stop monkeying with the Motorcraft distributors and get an MSD...it will save you ton's of grief...

And why would you go back to points?????