Step washers for aluminum heads
 

I'm about to install the Edmunds aluminum heads on my '51 Merc engine. I know I should run washers under the bolts. Doing some internet searches, I came across several kinds of "step washers", They are kind of expensive and require a special installation tool. Anybody ever use these or have an opinion on them?

Re: Step washers for aluminum heads
 

Seems like a tad of overengineering in this case...get a normal set of washers and spend the saved money on something else.

Re: Step washers for aluminum heads
 

I have used them, in both flatheads and overheads, they work good.

Re: Step washers for aluminum heads
 

So I noticed there is some play in the fitment of the Edelbrock heads I have. Not a lot but enough. Would something like that take out the play and stabilize them? Would the heads have to be machined for them?

Re: Step washers for aluminum heads
 

"They work good"? Just exactly what do they do that is different than what flat washers have been doing for decades?

Re: Step washers for aluminum heads
 

Hi Denny, you don't really need that type washer, they are mainly used for installing Ford heads with 1/2" head bolt holes on blocks that have 7/16" holes.

We have special (thinner) washers for aluminum or iron heads where customers want to keep stock length OEM head bolts.

I do agree with the idea of keeping both the heads and the gaskets from "moving-around", this is the main reason we began "pinning" the heads to the blocks years ago. It's done while we do all the machining on the blocks and heads.

Thanks, Gary in N.Y.

P.S. Here's a couple shots of the washers and the finished "pinned" block. The pin job is accomplished with a special block-plate we use also for finish-honing the blocks.

Re: Step washers for aluminum heads
 

Gary,

Thanks for chiming in. It seems we both agree on trying to keep the heads from "moving around". Keep in mind that in this case, we are talking a used engine. Ideally. I think "pinning" would be preferred, but believe this to be a good solution where machining the block for pins is impractical. Since a flathead uses the same size headbolt (7/16") as a SBC and some others, the cost is manageable, especially given the price of specialized thin washers. The one problem I have is that while some of the folks selling these mentioned a "special installation tool", nobody seems to have one. Perhaps you, being in the business, can point me to source?

Denny

Re: Step washers for aluminum heads
 

Hi Denny, do yourself a huge favor and forget this method. In all likelihood you run the risk ruining the heads by trying to get all 24 inserts to align perfectly with the existing head bolt holes. I would only attempt this deal on a CNC.

I can recommend an easier method to get the job done. Would need some very minor lathe work only. It would involve using 2 aluminum sleeve type bushings, one on each end of a single head bolt hole. This is the exact method we use to begin the "pinning" of the blocks/gaskets/heads. See the photo below, fairly simple and it WILL work. This will also allow you to still use the washers I mentioned above.

Thanks, Gary in N.Y.

P.S. Here's the "alignment" dowels we use to set up/align the plate before the actual "pinning" begins! The aluminum tubing is readily available from many online vendors. You could use similar sleeves but with a .530" O.D. (nominal) x .437" I.D. and work with only 4 head bolt holes?

Re: Step washers for aluminum heads
 

If you go with flat washers, use hardened Grade 8, .070" thick. Bought mine from Albeco in Tewsksbury MA. $3.84 for 48, @ 08. cents each. Fastenal has the same ones. Roy Naciewickz, about .020 thicker, advertised as hardened, no grade listed. About $20. for set of 48 if my memory serves me. How about all those flatmotors running aluminum heads all these years with steps or pins.

Re: Step washers for aluminum heads
 

Hi Russ, here's the main issue with mostly newer castings although we see "larger-than-normal" head bolt holes on some older models as well. Some years back I had a discussion about this with a contact out at Edelbrock and wanted to know why they had enlarged the head bolt holes substantially?

Here's what I was told, (Quote) we were constantly getting complaints about not being able to "slide" the heads down onto the block with the studs already in place. Therefore we made an attempt to help this issue by modifying (enlarging) the head bolt holes in the later castings (End quote).

This got our attention and caused us to start the head-pinning procedure. It has worked rather well over the years. Also, on side note, anyone wanting to change to different heads on any block we had previously pinned here can have the new heads done and not worry about fitting the existing pin locations. It's all done on a fixture. It would require shipping the new heads back & forth however!

The ride in my signature is a testament to the quality and effort put into these units. There's probably over 30,000 miles on it by now and has been out over 6 years now. Dynoed at over 150 HP and over 260 FtLbs Torque. I firmly believe this particular one will go 100,000 or better.

Thanks, Gary in N.Y.

P.S. Over the years of doing these Flatheads we've found the block-plate finish-honing AND the pinning of the heads to be most important, whether looking for any slight HP gains or just for "peace-of-mind", these are all positives. Along with these 2 items on ANY builds done here we do the bronze liners, on our own units there's no room for discussion on these 3 procedures, it doesn't add all that much to the cost in the larger picture! We have done these procedures for years and not a SINGLE customer complaint!

Re: Step washers for aluminum heads
 

GM does something like this on some of its engines, including the BBC and modern LSx blocks. It works well.

Re: Step washers for aluminum heads
 

Gary,

The aluminum bushings seem to be a better idea (and cheaper, too)! From looking at your jig, it looks like 4 sleeves per engine (two per side), right? I'm going to investigate this avenue. Thanks for the help and advice.

I'm ending up doing things with and for this engine I never would have imagined 25 years ago. It'll be interesting to see how everything turns out.

Denny

Re: Step washers for aluminum heads
 

They work well for heads that have been badly beat up over the years. Some heads are softer then other and use of no washers have the bolts holes deformed and cracked in some cases. These are a way to fix some of that.