Clevelands dropping valves

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Dec 24, 2003 | 09:00 AM

78ford100

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From: Western IL

Clevelands dropping valves

I've heard stories and seen pictures of clevelands dropping valves. This seems pretty common. Were there any particular years, or models (2v or 4v) that were prone to this? Has anyone had this happen to them?
Thanks,
Justin

Dec 24, 2003 | 09:10 AM

beartracks

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From: Albuquerque

I've never heard of that problem. Actuall 4v 351c's are meant for high rpm use and need to have proper valve train set up. The 2v head probably don't have adjustable valve trains from the factory and this can be a problem if not addressed.

Dec 24, 2003 | 04:22 PM

mudcobra

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From: West Kentucky

I've never ran across the problem either, but, most clevelands use multi grove valves allowing them to rotate, thus wearing them down and causing them to "drop". I've always been advised to switch to single groove valves and keepers when building a performance engine, thus elminating the rotation.

Dec 26, 2003 | 11:24 PM

78ford100

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From: Western IL

I'd heard of the valve keeper problem. I've been watching some other heads that really look nice, so i'll hopefully get a set. I will most likely get stainless valves put in those.
Thanks guys,
Justin

Dec 27, 2003 | 03:56 AM

scroob

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The only Ford engines I heard of dropping valves are the 385 series blocks with early heads. They used rail guided rocker arms. When the rocker arm and valve tip wear enough, the rails can bear on the valve spring washer, and the keeper can dislodge.

Just for the record, I own a 429 with these early heads. It has over 200,000 miles on it, and none of the rails are even close to touching.

But, it CAN happen.

Dec 29, 2003 | 08:56 AM

CJJTulsa

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Joined: Jan 2003

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It's not just the multi-groove keepers that make them drop -- it's the two-piece design from what I hear is the biggest problem. The valves get old, then pop the heads off. I haven't had it happen, but from what I hear it isn't at all unusual.