2N manifold/tappet cover interference

Kennelson

New User
I"m completing a very long 2N restoration. For two days I"ve been trying in vain to start the engine. I just found that its not aspirating because there is a gap between the manifold and the block caused by interference of the two tappet covers. They appear to be projecting slightly up behind the manifold and its gasket, so I"m sucking air through a gap instead of from the carburetor. I know I can fix it by slightly cutting back the flange on the covers, but why is this condition present? Certainly Henry"s engineers did better than this.

The block and covers are a replacement for the former cracked block, and the serial number is from "43. The cover flange is the same width on both top and bottom, and its bolt/nut allow no up/down positioning.

Any ideas why this is so? If I must, I"ll cut the cover to fit, but it just doesn"t seem necessary.
 

I had the identical problem when I replaced the manifold with an "aftermarket" one from China or India. I had to alter it a bit with the grinder to make it fit correctly. Any chance you have one of those replacement manifolds?
 
Thanks for the reply, Dan.

I don't know if it was ever replaced in the past, but now you've given me good reason to think so. That being the case, I'll make the alterations necessary and get on with my life.

Did you grind away part of the manifold flange?

My four year project is just .020 inches away from completion, an' I'm hot-to-trot. Apparently my 2N's not all original, but she's a beauty, all the same.
 
(quoted from post at 15:57:34 10/31/09) Thanks for the reply, Dan.

I don't know if it was ever replaced in the past, but now you've given me good reason to think so. That being the case, I'll make the alterations necessary and get on with my life.

Did you grind away part of the manifold flange?

My four year project is just .020 inches away from completion, an' I'm hot-to-trot. Apparently my 2N's not all original, but she's a beauty, all the same.

Yes, I only had to remove a small amount of the cast material on the manifold flange to clear the valve covers. As I recall, it was a close fit with the original anyway.
 
kennelson,

I agree with Dan...and, the quality of the manifolds has been getting worse. One of my suppliers has identified what it thinks is the problem, and I tend to agree (having fought with a few in past).

What they think we're seeing is the result of making of a copy of a copy of a copy when the foundary guys tool up new casting patterns. Each generation is a little different. I've seen this on Ford, Farmall and Moline manifolds on my own machines. Each time I would put a new manifold on something...I always had to tweak it...file here and there, to get it to go.

What my supplier claims to have done is to go back to a verifiable mid-40's Ford N manifold and make their patterns from that. I've sold a few of these recently and all customers seem to be very happy. Do I know for sure my supplier's telling the truth? No...not for sure. But, I will say, they are excellent looking parts!
nnalert Tractor
 
Same as the others, had to grind part of the manifold. There was lots to work with, so much so it overlapped the valve covers :-)

If you dont have one Harbor Freight has a 4.5 inch grinder for 29.00 bucks on occasion. The only real problem with it is it weighs twice as much as an 80.00 grinder and has a crude on/off siwtch. I have 1 HF one with a hard wheel on all the time and a Makita that I change wire wheels, cup wheels etc.
 
(quoted from post at 21:15:00 10/31/09) I"m completing a very long 2N restoration. For two days I"ve been trying in vain to start the engine. I just found that its not aspirating because there is a gap between the manifold and the block caused by interference of the two tappet covers. They appear to be projecting slightly up behind the manifold and its gasket, so I"m sucking air through a gap instead of from the carburetor. I know I can fix it by slightly cutting back the flange on the covers, but why is this condition present? Certainly Henry"s engineers did better than this.

The block and covers are a replacement for the former cracked block, and the serial number is from "43. The cover flange is the same width on both top and bottom, and its bolt/nut allow no up/down positioning.

Any ideas why this is so? If I must, I"ll cut the cover to fit, but it just doesn"t seem necessary.

Its not the manifold are the covers,,, I will let those that blame it on the parts help ya to chifer it out,,, its a simple EZ fix no grinder needed
 
(quoted from post at 21:52:15 10/31/09)
(quoted from post at 21:15:00 10/31/09) I"m completing a very long 2N restoration. For two days I"ve been trying in vain to start the engine. I just found that its not aspirating because there is a gap between the manifold and the block caused by interference of the two tappet covers. They appear to be projecting slightly up behind the manifold and its gasket, so I"m sucking air through a gap instead of from the carburetor. I know I can fix it by slightly cutting back the flange on the covers, but why is this condition present? Certainly Henry"s engineers did better than this.

The block and covers are a replacement for the former cracked block, and the serial number is from "43. The cover flange is the same width on both top and bottom, and its bolt/nut allow no up/down positioning.

Any ideas why this is so? If I must, I"ll cut the cover to fit, but it just doesn"t seem necessary.

Its not the manifold are the covers,,, I will let those that blame it on the parts help ya to chifer it out,,, its a simple EZ fix no grinder needed

I am thinking the same as Hobo on this (I think), but since I have never dealt with a replacment manifold, have kept my mouth shut (so far).
 
you might want to check and make sure that the studs for the valve chamber covers are not bent, up (lay a square against them) many times the studs are bent due to prior mechanics using them as fulcrums to lift/compress the valve springs during service.
 
(quoted from post at 21:58:02 10/31/09)
(quoted from post at 21:52:15 10/31/09)
(quoted from post at 21:15:00 10/31/09) I"m completing a very long 2N restoration. For two days I"ve been trying in vain to start the engine. I just found that its not aspirating because there is a gap between the manifold and the block caused by interference of the two tappet covers. They appear to be projecting slightly up behind the manifold and its gasket, so I"m sucking air through a gap instead of from the carburetor. I know I can fix it by slightly cutting back the flange on the covers, but why is this condition present? Certainly Henry"s engineers did better than this.

The block and covers are a replacement for the former cracked block, and the serial number is from "43. The cover flange is the same width on both top and bottom, and its bolt/nut allow no up/down positioning.

Any ideas why this is so? If I must, I"ll cut the cover to fit, but it just doesn"t seem necessary.

Its not the manifold are the covers,,, I will let those that blame it on the parts help ya to chifer it out,,, its a simple EZ fix no grinder needed

I am thinking the same as Hobo on this (I think), but since I have never dealt with a replacment manifold, have kept my mouth shut (so far).

I think I will run my mouth a little, but don't hold me to this....

Seems I [b:ce0830e7d2]may[/b:ce0830e7d2] have encountered a similar problem on my last rebuild if my CRAFT is serving me correctly, and it was a, "how could this be".

But now let me tell you the leading up to this part.

I cleaned, and straightened my valve covers (on the anvil, and other ways to get the [b:ce0830e7d2]"spring"[/b:ce0830e7d2] back in middle of them), and put a little Ultra RTV Blue on the covers, and on one side of the cork gaskets, and put the gaskets to the covers, and let them set.

No RTV on the engine side of the cork gasket, only on the tin cover side, and that is just to hold them in place.

Put the valve covers on.

And then went to put my manifold on, "what the 'Ell"?

Ok, no problem, loosen the valve covers, put the manifold on, and then tighten the valve covers back down. And they fall into place.

Now the valve covers don't need to be that tight to seal this way.

Your mileage may vary.....

The "spring" in the middle of them, and them being in the original shape, is important, and if you tighten them too tight, you spread them.

HTH.
 
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