N series valve lash adjustment after rebuild

Location
Pride, LA
I know the recommendation is to do a valve lash adjustment after a break-in period once you’ve done a valve job. My side mount 8N is probably coming up on its 50 hour mark and I’m starting to wonder if those of you who did this lash adjustment post break-in found any that actually needed adjustment.

This is less a factor of me being lazy and more of me not wanting to snap off one of the lifter screws. I know they come right, but the brand new ones I installed I nearly rounded the heads off a few.
 
Hi Boda,
Sorry, I've not done a 50 hr valve lash check.
Are you holding the tappets with the sheet metal left and right tool, or are the bores drilled to use a punch?
Ive bent and then welded, then bent em again, dont use sheet metal holders anymore, or a grinded off wrench. (Or other device to hold from a top hole)
Hard to turn sliced bolt is from an old tappet...
8992.jpg

You can check each valve just to see if still in spec, may be still good--giving piece of mind.:)
If pull the spark plugs, and carb, the two valve chamber covers are easy to get to. Watch #3 exhaust valve and run the starter til it just starts to lift up, then just pry the flywheel teeth to get 0° through the timing window.
1678.jpg

Once tdc on compression stroke for #1, follow the manual procedure.
John
 
Whoopsie! I have never adjusted my valves; the engine was rebuilt 18 years ago, run hard, and still runs well with maybe a little tappet noise (nowhere near my old Vega). Guess I need to add that to my 'to-do' list.
 
Whoopsie! I have never adjusted my valves; the engine was rebuilt 18 years ago, run hard, and still runs well with maybe a little tappet noise (nowhere near my old Vega). Guess I need to add that to my 'to-do' list.
Sounds like I’ll add it to the 15 year PM lol. It’s developed a little cough at idle and once up to temp at about half throttle. But I suspect it’s likely an issue with the Chinesium Carb because I just can’t tune it out. Otherwise it runs good, the cooling system keeps up in the Louisiana heat, and it only drips from the governor seal, something I intend to fix when I recut the proof meter cable threads on the back.

But summer grass season is upon us, and so these things become winter PM’s lol.
 
Hi Boda,
Sorry, I've not done a 50 hr valve lash check.
Are you holding the tappets with the sheet metal left and right tool, or are the bores drilled to use a punch?
Ive bent and then welded, then bent em again, dont use sheet metal holders anymore, or a grinded off wrench. (Or other device to hold from a top hole)
Hard to turn sliced bolt is from an old tappet...
View attachment 156280
You can check each valve just to see if still in spec, may be still good--giving piece of mind.:)
If pull the spark plugs, and carb, the two valve chamber covers are easy to get to. Watch #3 exhaust valve and run the starter til it just starts to lift up, then just pry the flywheel teeth to get 0° through the timing window.
View attachment 156277
Once tdc on compression stroke for #1, follow the manual procedure.
John
When I originally set the valve lash I absolutely ruined the sheet metal tappet holders. The only way I could get any movement on the adjustment screw without rounding the head was to take the valve completely out of the head and go in with a long extension to use a 6 point socket. Quite a long valve job having to set more than half of the valve lash like that. And I’d frankly rather not muck around with taking the head off just to make a 2-thou lash adjustment lol.

But back to holding the tappet; I ended up having to use a punch. But after breaking off two of them in the lifter and having to fish it back out of the bore to retrieve, I ended up going with the biggest punch I could physically get into the hole drilled by the previous owner(s). This was after I had to open the bores up with a brake cylinder hone so that the lifters could actually rotate. I also had to file the ridges of the lifter cutouts because the tooling marks were interfering with the rotation.

All in all the rotating and valve assembly took 2 days to complete. Admittedly by someone whose first time seeing a crankshaft in real life was when he took the damn thing apart lol. So learning happened, and a little “figure it out along the way” happened as well.
 
Thanks for the update on your rebuild woes. 😃
Ive drilled the bores with a 3/16" bit, and not broke punch, or chuck side of 3/16" drill bit. But some are very hard to turn--- im talking the old ones.
Do your new lifter bolts look like the old one in my pic above?
From Ford owners manual
8995.jpg

8994.jpg
 
I honestly didn’t back them all the way out to see. It was such a frustrating day that I mostly blocked it from memory. I did find success working the bolt in and out a bit before putting the lifter in the bore to make the actual lash adjustment.
 
We all have struggles with new parts that dont work properly 😒
Its doubtful those super hard to turn lash bolts unthreaded, so if they were installed good, they likely still are. 😃

I could see a jig made from a short bit of steel pipe, with 3/16" holes, held in a vice. Lifter fits in the pipe, and is held by a punch (or two). Then loosen all the way, and tighten a few times to work the threads...

Could the lash bolt head be metric, maybe 11 mm?
 
Last edited:
When I originally set the valve lash I absolutely ruined the sheet metal tappet holders. The only way I could get any movement on the adjustment screw without rounding the head was to take the valve completely out of the head and go in with a long extension to use a 6 point socket. Quite a long valve job having to set more than half of the valve lash like that. And I’d frankly rather not muck around with taking the head off just to make a 2-thou lash adjustment lol.

But back to holding the tappet; I ended up having to use a punch. But after breaking off two of them in the lifter and having to fish it back out of the bore to retrieve, I ended up going with the biggest punch I could physically get into the hole drilled by the previous owner(s). This was after I had to open the bores up with a brake cylinder hone so that the lifters could actually rotate. I also had to file the ridges of the lifter cutouts because the tooling marks were interfering with the rotation.

All in all the rotating and valve assembly took 2 days to complete. Admittedly by someone whose first time seeing a crankshaft in real life was when he took the damn thing apart lol. So learning happened, and a little “figure it out along the way” happened as well.
I let a guy come into my shop to install free rotating valve set up on a block he was rebuilding. I am tooled up well to set up free rotating valves. He was intelligent enoufh read the manual and understand my instructions the first time. It took him the better part of a day to complete the job.

It adds a few hours onto the job when I do it : ( I would think if a guy did this everyday it would add a good hour to the job. Time is the #1 reason I don't recommend free rotating valves. I would charge an extra $300 to a already expensive job.

To answer your question I have never went back and checked them myself. On my own I have not and the ones I did for customers have never been back for any service work.

If those adjuster bolts were that tight you should have taken care of that when you had them in your hand. Another thing if you did not resurface the head of the adjuster bolt you set them up lose to begin with. The ware will come from the valve keepers on a free rotating set up in the end they just don't rotate anymore. I would not worry about it at this time I doubt this will ever be an issue.
 
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