Tappets?

fts1966

fts1966

Member
Okay doing research for the engine rebuild. my engine looks to have the original no adjustment tappets. I want to do adjustable ones. I would like know and understand the differences and if one is better or easier to adjust than the other.

Single self locking style?

Double self locking style?
 
ive heard double is better as you can lock it down harder - if the single gets loose theres no way else to lock it down besides some form of locktite.
 
I tried to use the double lock tappets for the reason above. However, I gave up and sold them and bought the single lock type. The reason was it was a real pain to try to get a wrench (even the thin tappet type) on the lower nut. I had to release the valve spring to get the bottom nut exposed enough to get a wrench on it. Maybe I just didn't know how to adjust double lock tappets, but I had no problems whatsoever with the single lock type.
Rusty Nelson
 
More important that single or double nut is the base diameter. If it's too small, the cam and tappets can be wiped out. The cam lobe must NOT strike the very outer edge of the tappet because it won't last long.
 
I prefer the single-lock for the same reason Rusty does. I have built and raced several engines and have never had one loosen on me. My procedure is to to install crank, lifters and cam only, before putting pistons in, this allows you to turn the engine over easily. I use the system of 9's and first adjust a lobe using your thumb to hold the valve closed when measuring clearance. You can easily lift the tappet to adjust, eliminating the need to constantly rotate the engine until that tappet is adjusted. I then install the springs and recheck the clearance. Good luck!
 
Jim Brierley said:
I prefer the single-lock for the same reason Rusty does. I have built and raced several engines and have never had one loosen on me. My procedure is to to install crank, lifters and cam only, before putting pistons in, this allows you to turn the engine over easily. I use the system of 9's and first adjust a lobe using your thumb to hold the valve closed when measuring clearance. You can easily lift the tappet to adjust, eliminating the need to constantly rotate the engine until that tappet is adjusted. I then install the springs and recheck the clearance. Good luck!
Click to expand...

Jim, that constant rotation can be a pain. But I am curious how you measure the correct piston location, and therefore the correct cam lobe position, without the pistons. :confused:
 
Be careful what you buy. We build engines. Their are two national vendors that are having Chinese ones made that suck in many ways. They retail for around $85 set. the good ones are USA made by Colony and are $100 set. You can get the good ones from Bert's or Snyders.

Steve @ Bert's
modelastore.com
 
700rpm said:
Jim, that constant rotation can be a pain. But I am curious how you measure the correct piston location, and therefore the correct cam lobe position, without the pistons. :confused:
Click to expand...
Everything should be in order when you put the crankshaft in and the timing marks between crank and camshaft line or am I missing something here

Sent from my SM-J700T using Tapatalk
 
Quote:
Originally Posted by 700rpm View Post
Jim, that constant rotation can be a pain. But I am curious how you measure the correct piston location, and therefore the correct cam lobe position, without the pistons.

Everything should be in order when you put the crankshaft in and the timing marks between crank and camshaft line or am I missing something here
Click to expand...

Adjust valve clearance when the lifter is on the heel of the cam, it doesn't matter where the piston is.
 
700, when #1 valve is fully open, adjust #8 valve 8+1=9. With #2 up, adjust #7, etc. etc. Some Model A books will tell you that you can adjust several valves at the same time, this doesn't work on a performance cam.
 
re; More important that single or double nut is the base diameter. If it's too small, the cam and tappets can be wiped out. The cam lobe must NOT strike the very outer edge of the tappet because it won't last long.

The original base was about 1 1/8" this is the size you would want to be using. Some of the repos only have 1" which can cause issues with the lobs on your cam as Tom said.
 
Katy and Jim, I understand and use that 9 system when I can see and measure the position of the pistons in the cylinders, as when the head is off. But when the engine is assembled, I can see neither the cam lobes nor the pistons, so I set #8, for example, when#1 looks fully open. But a couple degrees off can effect the clearance, no? So I get #1 where it looks like it’s fully open, but it’s just a guess relying on my eyeball. I don’t really know if it is on the heel of the cam or not. See my problem?

BTW, this isn’t my first rodeo. I’ve struggled with this question for years. :p And my cars all run fine, so just how critical is that clearance anyway? I’ve read everything from i010/e015 to set ‘em all at 015. And I’ve heard it said, “Better to hear ‘em than burn ‘em.” And I believe that.
 
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I adjust the valves one at at time. You can eyeball when the lobe is fully up, ie, the valve is fully open. Then rotate the crank pulley one full revolution, which rotates the camshaft 180 degrees, and the lifter will be on the heel of the cam and in the correct position to be adjusted. Do not fall into the trap of thinking that when the piston is at top dead center (and both valves are closed) that the cam lifters are on the heal of the cam. They are not, and any adjustment in that position will be off.
 
I adjust the valves one at at time. You can eyeball when the lobe is fully up, ie, the valve is fully open. Then rotate the crank pulley one full revolution, which rotates the camshaft 180 degrees, and the lifter will be on the heel of the cam and in the correct position to be adjusted.
Click to expand...

Ditto
 
fts1966 said:
Okay doing research for the engine rebuild. my engine looks to have the original no adjustment tappets. I want to do adjustable ones. I would like know and understand the differences and if one is better or easier to adjust than the other.

Single self locking style?

Double self locking style?
Click to expand...

These are NOT the first questions you need to be asking.
You need to first and foremost, determine what cam you have. Most aftermarket PERFORMANCE cams are designed to run on a 1 inch diameter face, lifter. The double lock lifters fall in this category.
However, you can run the single lock lifters on these cams with no bad effects.
If you have a stock or a reground stock cam you need the single lock lifters because they have a face close to the diameter of the original Ford lifters. (approx 1.125)
The stock cams have no clearance ramps so it requires a larger face lifter.
 
PETE,

Thank you. that is very good information im running the original cam reground.
I have the information written down in my book now for what to use and why.
I appreciate the answer to my question.
 
Tom Wesenberg said:
More important that single or double nut is the base diameter. If it's too small, the cam and tappets can be wiped out. The cam lobe must NOT strike the very outer edge of the tappet because it won't last long.
Click to expand...

Colony is the name of the manufacturer that has the correct diameter base of about 1-1/8" needed to avoid camshaft damage. I use their single lock tappets with good results. Never had one loosen...
Good Day!
 
After reading this thread, I panicked and checked the adjustable tappets that I had purchased a few years ago to build a spare engine for my Model As. I checked them and sure as hell, they are about 1/8 inch smaller in base diameter than stock ones. I am not even sure where I purchased them, so return is not an option. They are exactly the width of the cam lobes. Will these cause problems for my cam? Should I just junk them and buy good ones? Being car poor, I have waited to assemble this engine and another $100 seems like a lot right now, but early failure of this engine would be even more expensive. What do you think.... A. give up beer?:rolleyes:...B. put the junk tappets on Ebay and pass along the problem? :D..C. Wait for my ship to come in?;) D. use the tappets and go to church a bit more often? :)
No option seems right. Seriously would I have much of a chance of getting by with these tappets ?
 
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