Installing new pushrods AND lifters

[TQuentin1]

What you are trying to do is adjust the PRs at least half the total lifter piston travel length. For the HD lifters this is around 0.200". So half of that would be 0.100". Depending on the TPI of the PRs you use, then that will determine the number of threads (turns) that you need to make to get that travel:

24 TPI: 0.100 x 24 = 2.4 turns
28 TPI: 0.100 x 28 = 2.8 turns
32 TPI: 0.100 x 32 = 3.2 turns

Some of us like to make the PR a flat or two further out than half the lifter piston travel so that the PRs inflate with less oil required. This usually means a quieter lifter. But that is a matter of personal preference. As long as the adjustment is somewhere around half the lifter piston travel, the lifter will work right.

TQ

 

[Jack Klarich]

Any time a hydraulic lifter is involved I always soak them over night. Solids and pre Evo motors were way different, you would bleed the tappet down, pump it up dry, count to 3 to see if it bled down, this was the test for a good tappet in the old days, plus adjusting those valves was a lot more forgiving JMO

 

[2000classic]

Ive been doing some reading about adjusting pushrods. Put them in make them finger tight, turn 3.5 turns. At this point then will be tight. Wait 15-20 minutes for bleed down and they should loosen enough to be able to rotate. Now my question is if I'm also putting in new lifters then they won't have any oil in them, hence no bleed down. So should I go 4 full turns? Or?

To answer your question. Go the recommended number of turns on the pushrods, oil or no oil makes no difference. Here is what is happening when you make those turns on a lifter with oil in it. Instead of pushing the piston inside the lifter to the center of its travel, you are pushing the valve in the head open. Once set, you must wait for the pressure of the valve springs to push the pushrod/lifter piston back down to the point of 1/2 of its travel by forcing oil out of the lifter. With new lifters with NO oil in them, there will be little or no wait time for bleed down as there is NO oil to be pushed out. So to summarize, DO soak the lifters before install. Set to recommended by manufacture, turns. Wait till you can spin pushrods freely before rotating the engine. Hope this helps.

 

[tourbox]

To answer your question. Go the recommended number of turns on the pushrods, oil or no oil makes no difference. Here is what is happening when you make those turns on a lifter with oil in it. Instead of pushing the piston inside the lifter to the center of its travel, you are pushing the valve in the head open. Once set, you must wait for the pressure of the valve springs to push the pushrod/lifter piston back down to the point of 1/2 of its travel by forcing oil out of the lifter. With new lifters with NO oil in them, there will be little or no wait time for bleed down as there is NO oil to be pushed out. So to summarize, DO soak the lifters before install. Set to recommended by manufacture, turns. Wait till you can spin pushrods freely before rotating the engine. Hope this helps.

2000Classic I like that explanation. I never thought of it that way,oil vs. no oil. But it makes sense to my logic.
tourbox

 

[Adamal47]

To answer your question. Go the recommended number of turns on the pushrods, oil or no oil makes no difference. Here is what is happening when you make those turns on a lifter with oil in it. Instead of pushing the piston inside the lifter to the center of its travel, you are pushing the valve in the head open. Once set, you must wait for the pressure of the valve springs to push the pushrod/lifter piston back down to the point of 1/2 of its travel by forcing oil out of the lifter. With new lifters with NO oil in them, there will be little or no wait time for bleed down as there is NO oil to be pushed out. So to summarize, DO soak the lifters before install. Set to recommended by manufacture, turns. Wait till you can spin pushrods freely before rotating the engine. Hope this helps.

This was exactly what I was looking for. Thank you. Do you guys
Recommend any specific lifters. I am probably going with
S&S ez install pushrods.

 

[tourbox]

When I have changed the lifters on on my bikes I usually go back with OEM.I will put in OEM lifter blocks as well.These are usually around 80k miles,Shovels & Evos.I figure why new lifters in OLD lifter blocks. I don't run big HP motors.There are several very good lifters out there, just depends on what you want for an end results. You didn't state how many miles on your '97 Softail.
tourbox

 

[Adamal47]

65k on the ole girl. Do lifter blocks go bad?

 

[tourbox]

65k on the ole girl. Do lifter blocks go bad?

Yes they do wear from the movement of the lifter,up & down.I looked at Ronnie's HD parts finder and they look like retail is about $81.00 each. I would change them for peace of mind, due to age, and mileage. But that's me.
tourbox

One other thing I do while in it that far is to put in a new Torrington cam bearing. Their cost is somewhere around $10-$12,aftermarket. I think the torrington # is B138.You may be able to get it cheaper at a bearing supply house. It takes a special remover & installer tool though.
tourbox

 

[R_W_B]

. . . . . .
IF you push a lifter DOWN internally, it will return to the top position OIL or NO OIL. . . . .

Any time a hydraulic lifter is involved I always soak them over night. Solids and pre Evo motors were way different, you would bleed the tappet down, pump it up dry, count to 3 to see if it bled down, this was the test for a good tappet in the old days, plus adjusting those valves was a lot more forgiving JMO

To answer your question. Go the recommended number of turns on the pushrods, oil or no oil makes no difference. . . . . . . . . With new lifters with NO oil in them, there will be little or no wait time for bleed down as there is NO oil to be pushed out. So to summarize, DO soak the lifters before install. Set to recommended by manufacture, turns. Wait till you can spin pushrods freely before rotating the engine. Hope this helps.

All excellent replies. Set to spec'd turns and then make SURE you can spin the pushrods with your finger before turning the crank to the next. Otherwise you might jam a valve into the piston. On cages we don't usually have to wait on the bleed down but water cooled engines usually only have 3 to 5 flats of preload.

Air cooled engines expand more when hot and going 20 flats or so into the preload is a substancial amount of protrusion if you don't wait on it to bleed down.

When you engine is all set and it cranks normally the bleed downs are already in place and the lifters then pump up to contact and stop from the pressure of the valve. Only time there is a problem during run time is when you adjust the pre-load too far and at high RPM the lifters do not have enough time to decompress before they are pumped again and they will sometimes do what's call "pump up" and that can float your valves. Racers will put in heavier springs to alleviate this but that wears on your cam more.

 

[Jack Klarich]

65k on the ole girl. Do lifter blocks go bad?

Indeed they do, but the EVO motors are more forgiving. You CAN change the lifter blocks and the lifters. The Twin cam lifter blocks are cast in the crank case,( this may be a problem) on extremely high mile motors JMO