Starting to work on my 68

[frnkeore]

I'm starting to pull my 68 engine apart. It's in the 1935, Model 51 truck that is pictured in my avatar. The finished product, will have the aluminum heads and intake that I recently got. My biggest focus on this engine, will to be to get as much compression as I can and will try to modify domed pistons and the flat top heads, to except each other with a minimum head to piston clearance of .035 - .040. I'll do that with my domed pistons, before boring.

The engine has the water pump block off plate but, I couldn't find a LB, stamped into the top of the block, on the RF. There is a stamping but, I can't quite make it out. At best, it could be a B in part of a circle. I've included a picture as best I could photograph it. It's the first pic.

The engine is .040 over and and has heavy pitting so, I think .060 will be what it has to go to and that may not get it all. The engine is locked up so, I'm soaking it now. I think I'll be able to get it to turn, within a few days.

The Ford script head gaskets measure .060, with a couple of places at .058 and the water pumps are in excellent condition.

I'll post more as I go. I think it will be fun, at least keep me busy, through the fall and maybe winter.

Frank

[Clem Clement]

have fun!!

[Fordestes]

Keep us posted on the head modification , sounds interesting.

[Kurt in NJ]

If it has block off plates it is at least a 37, and it will be inserted, you won't find a "LB"

[frnkeore]

Thanks, Kurt. That's one thing that I wanted to know.

Another question that I have, is that the piston marking has N-.040. What does the N mean?

[Brian]

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Oh Boy!! You're talking foreign to most guys on here. Most of them rubbish 21 stud engines. I, however, believe they are the best engines Ford produced.
You have a 37-38 block as evidenced by the block off plates. I too use this block with earlier pump in head heads etc. You can attach a zinc sacrificial anode inside each block off plate to assist in protecting your al heads.
You cannot machine your heads to achieve the squish you're after until the engine is at least mocked up. Also, I believe you can achieve higher compression through running flattop pistons, not domed [simple arithmetic]
You should be able to bore that 37 block to at least 3 3/16.
I'll follow your build progress with interest.

[frnkeore]

Brian,
Thank you for the tip on the zink anodes, I'll do that.

My first though about this engine, was to use standard 3 3/16 pistons to rebuild it. That was before I started looking for a head gasket for the 21 stud block, that would allow that size piston.

In doing that, I did find a gasket that is 3.154 and no larger ones. Then after I was sent, a pair of Victor, composite gaskets from a wonderful forum member (thank you Bob) I've found that there is no way to bore the engine to 3 3/16", because, it will be up against the lower head stud, with no room for a gasket.

I saw a 21 stud, over on the Flat Spot, that had sleeves in it. Ford sleeves are .040 thick and I believe that, that bore (3.143) would be the max, safe bore. If my bore doesn't clean up at .060, I may have to get simi finished pistons to go to .070 over. The problem with that, is finding rings.

Does anyone have a source of rings, in the 3.133 to 3.143 range?

After I get the engine out and on a stand, I'll measure and get the distance from the center of the bore, to the bottom head stud and post it.

Thank you all for your input.

Frank

[Brian]

Frank, My current engine in my 35 is a 21 stud displacing 255 cu inches; 3 3/16 bore x 4" stroke. So your statement of not being able to bore to 3 3/16 is way wrong!! Actually had the block sonic tested prior to machining, and the guy said it'll go safely yet another .020"



Not that I run them, but Cometic can make gaskets for your 21 stud that will accommodate 3 3/16 bore.


Hastings can do you rings for any oversize

[Brian]

Seeing as your vehicle is a truck, I wonder if you'd be better off fitting a later, more powerful engine?

[frnkeore]

Brian,
Thank you for the additional info.

I'm going to stick with this engine. I have always loved the look of the head mounted water pumps. It just looks "right" to me and now that I know it has a insert block, I will rebuild it. I've had this truck since 1995, just as pictured but, I didn't get serious about doing anything about it, until I got the aluminum heads and intake, last month at a auction.

I've always liked having something different and in FH's this qualifies. Ultimately the truck could in up with a SBF and this engine, in a 8N tractor. What I need to do with the drive train, will be the deciding factor.

Oh ya, the reason I bought the truck, in the first place, was that I basically learned to drive, in a '36 PU, in '57 when I was 12. We lived on 8 ac and I made many roads with it. Sine then, the '35 & '36 trucks have been my favorite early Ford truck.

Gas was my only problem, in those years.

Frank

[bobH]

Frank, something to consider & keep in the back of your mind regarding head gaskets.... Ol Ron has posted a few times regarding this: If you want 'big-bore' gaskets, simply take 59A (239) gaskets, and punch the couple holes you will need to make them work on a 21-stud. Use your 21-stud heads as a guide, and simply punch the holes. Ron even posted how he made his punch. I've tried this once & it worked fine. (Thanks Ron.)

[frnkeore]

Thank you Bob. I had wondered about that when I first started looking for head gaskets but, I didn't have a 24 stud engine or gasket to compare.