Quick valve lash questions...

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Icetech

Icetech

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K.. so i tend to overthink and make myself nuts.. my 318 has a roller cam with oem lifters, trick flows and mancini 1.5 aluminum rockers. I have had valve noise that i have been chasing i have lashed the valves 3-4 times now 1/2 turn 1 and now 1 1/2 turn a full turn should be .040 so right now i should be at .060 preload.. doing searches i see guys saying .020 is plenty, mine at .020 sounds like a slant 6 that was never taken care of.. And i see posts saying .080-.090.. i don't want to go that tight really..

So at .060 the noise is there but it's pretty quiet, the sound is uniform and not like 1-2 lifters clattering so it's probably fine. One thing annoying me though was when lashing some of the lifters don't seem to bleed down, like 1/2 turn and i hit resistance and had to put some decent pressure to get the 1.5 turn in.. My main question is will they basically self adjust the oil in the lifter on startup even if they sat for 2 months and some didn't bleed down? I have no popping in the exhaust or intake so no valves being held open at all. I just want to verify.. and next time i am 100% going solid, no guessing and preload **** :)

Only other issue now is my carb is still crazy rich at idle, like melt my eyes out rich. Gonna take it apart to check float levels at a later date, and get a pressure gauge to check pressure, have read that the street demon doesn't like a lot of pressure.
 
Icetech said:
Only other issue now is my carb is still crazy rich at idle, like melt my eyes out rich. Gonna take it apart to check float levels at a later date, and get a pressure gauge to check pressure, have read that the street demon doesn't like a lot of pressure.
Click to expand...
That burn-your-eyes-out exhaust, is the sign that your engine wants some Idle-Bypass Air, or has in intake leak sucking oil.
On a street car, with a cam of less than 292/292/108advertised, (the biggest I have tuned); and with a standard 2-corner idle system
1) Reset your Transfer Slot exposure to a little taller than wide,
2) reset you mixture screws in the middle of their operating range,
3) after this do not touch the speed screw.
4) Using Ignition timing, Idle your engine down to around 700>800,
5) introduce some Bypass air into the PCV system. a little atta time, until your timing is down to ~14 degrees with a consistent happy idle.
I do this by Tee'ing into the PCV system with a plastic pipe capped on the end. Then I drill two holes into the pipe, starting at 1/16 inch each. Do not exceed 3/32 unless you are very sure you need that much. Then drive it around for a couple of hours.
Then re-access the results. If you drill too-big holes,(1/8th would be too big for sure) the Idle-rpm will go too high, and to get it back down, you will have to take timing out. So it's better to be a hair too small with a slightly higher idle.
6) after you get rid of the stink; you can reset your mixture screws.
6a) if you find that the engine idles best with the mixture screws set lean, then the low-speed circuit is already too rich, so CLOSE the speed screw a tad, which will close the transfer. maybe in the range of 1/4 to 3/8 turn. Then richen the mixture screws back towards the middle.
6b) If it idles best with the mixture screws rich, then go the other way.
6c) when that has been set, revisit your idle speed. If too slow, add a bit of timing. If too fast subtract some timing.
7) what is too fast/ too slow?
7a) If too fast, it will bang into gear and/or lurch the car. This happens because the engine is idling at too high a power setting, most likely because it has too much timing. Do not upset the transfer slot synchronization by adjusting the speed screw; leave it alone. The right thing to do is to retard the idle timing. If it gets to be below 12* most likely your bypass holes are too big.
7b) If too slow, either the timing is too retarded, or the engine wants MORE bypass air; give it a touch more bypass, and start over.
8) once you get the size of the bypass holes figured out, you can prove the measurements and transfer the holes to the Primary throttle blades; ONE HOLE in each, and I drill them on the front side between the discharge ports pointing the holes at ~5/16ths from the front edge. I chamfer both sides just a bit.
Don't forget to remove the Tee.



There are other methods;
1) If you have a 4-corner idle system you can crack the secondaries. But if your cam is too small, this may just make it worse.
2) If your carb has replaceable air bleeds, you can accomplish the same thing with those.
 
AJ/FormS said:
That burn-your-eyes-out exhaust, is the sign that your engine wants some Idle-Bypass Air, or has in intake leak sucking oil.
On a street car, with a cam of less than 292/292/108advertised, (the biggest I have tuned); and with a standard 2-corner idle system
1) Reset your Transfer Slot exposure to a little taller than wide,
2) reset you mixture screws in the middle of their operating range,
3) after this do not touch the speed screw.
4) Using Ignition timing, Idle your engine down to around 700>800,
5) introduce some Bypass air into the PCV system. a little atta time, until your timing is down to ~14 degrees with a consistent happy idle.
I do this by Tee'ing into the PCV system with a plastic pipe capped on the end. Then I drill two holes into the pipe, starting at 1/16 inch each. Do not exceed 3/32 unless you are very sure you need that much. Then drive it around for a couple of hours.
Then re-access the results. If you drill too-big holes,(1/8th would be too big for sure) the Idle-rpm will go too high, and to get it back down, you will have to take timing out. So it's better to be a hair too small with a slightly higher idle.
6) after you get rid of the stink; you can reset your mixture screws.
6a) if you find that the engine idles best with the mixture screws set lean, then the low-speed circuit is already too rich, so CLOSE the speed screw a tad, which will close the transfer. maybe in the range of 1/4 to 3/8 turn. Then richen the mixture screws back towards the middle.
6b) If it idles best with the mixture screws rich, then go the other way.
6c) when that has been set, revisit your idle speed. If too slow, add a bit of timing. If too fast subtract some timing.
7) what is too fast/ too slow?
7a) If too fast, it will bang into gear and/or lurch the car. This happens because the engine is idling at too high a power setting, most likely because it has too much timing. Do not upset the transfer slot synchronization by adjusting the speed screw; leave it alone. The right thing to do is to retard the idle timing. If it gets to be below 12* most likely your bypass holes are too big.
7b) If too slow, either the timing is too retarded, or the engine wants MORE bypass air; give it a touch more bypass, and start over.
8) once you get the size of the bypass holes figured out, you can prove the measurements and transfer the holes to the Primary throttle blades; ONE HOLE in each, and I drill them on the front side between the discharge ports pointing the holes at ~5/16ths from the front edge. I chamfer both sides just a bit.
Don't forget to remove the Tee.



There are other methods;
1) If you have a 4-corner idle system you can crack the secondaries. But if your cam is too small, this may just make it worse.
2) If your carb has replaceable air bleeds, you can accomplish the same thing with
Click to expand...
Wow, thank for writing that up.. that's a good list for me to run though. Gonna be a couple of weeks til i get to it
 
As to the ticking lifters, don't forget that there are other common sources of ticking .... such as
1) rockers hitting the retainers,
2) pushrods hitting the pushrod tubes
3) pushrod ends not matching the sockets
4) rocker to rocker slap
5) exhaust header leaking
6) not lashing correctly.
7) a rocker arm hitting the oil-Baffle in the VC under the PCV or oil-filler cap.
8) crank hitting the dipstick, or the tray.
9) if using the factory dogbones, is it possible for those to be noisy? IDK.
10) I suppose I should add insufficient piston to valve or piston to head clearances, lol
 
AJ/FormS said:
As to the ticking lifters, don't forget that there are other common sources of ticking .... such as
1) rockers hitting the retainers,
2) pushrods hitting the pushrod tubes
3) pushrod ends not matching the sockets
4) rocker to rocker slap
5) exhaust header leaking
6) not lashing correctly.
7) a rocker arm hitting the oil-Baffle in the VC under the PCV or oil-filler cap.

10) I suppose I should add insufficient piston to valve or piston to head clearances
Click to expand...
hmm.. i checked rockers to retainers, and checked pushrod clearance when i put it together, i will double check it though.
 
Also, to add to the carb “t” slot info.
You changed this engine drastically from stock. Don’t expect it to run or idle like stock 100%. Many times after a cam swap people want this engines to act like stock. Low vacuum from a lopy cam will mess with your idle and the transfer slots will not cover the needs. At that point a happy medium is needed. Less eye burning and better idle is the best you get.
 
Syleng1 said:
Also, to add to the carb “t” slot info.
You changed this engine drastically from stock. Don’t expect it to run or idle like stock 100%. Many times after a cam swap people want this engines to act like stock. Low vacuum from a lopy cam will mess with your idle and the transfer slots will not cover the needs. At that point a happy medium is needed. Less eye burning and better idle is the best you get.
Click to expand...
Yeah, i'm not expecting a great idle and all that.. but would like to not have black sooty plugs from 5 mins of idling :)
 
So is this a Magnum? At any rate, hydraulic rollers generally need a bit more preload than flat tappets. So it's not surprising to see you going with more preload. Also, there's a right way and a wrong way to install factory style hydraulic roller lifters, although you didn't specify, I'll assume that's what you're using. The oil holes in the lifter bodies should all face the center of the engine. If they face the outside, they can bleed off some of the oil that needs to be retained, since that side is facing downhill. People argue over it, but I've witnessed it. It happens, stupid as it sounds.
 
RustyRatRod said:
So is this a Magnum? At any rate, hydraulic rollers generally need a bit more preload than flat tappets. So it's not surprising to see you going with more preload. Also, there's a right way and a wrong way to install factory style hydraulic roller lifters, although you didn't specify, I'll assume that's what you're using. The oil holes in the lifter bodies should all face the center of the engine. If they face the outside, they can bleed off some of the oil that needs to be retained, since that side is facing downhill. People argue over it, but I've witnessed it. It happens, stupid as it sounds.
Click to expand...
LA roller with oem lifters.. and i had not read that thing about the oil hole facing center but it makes perfect sense... things i wish i had known a year ago :)
 
Icetech said:
mine at .020 sounds like a slant 6 that was never taken care of
Click to expand...
Exactly the same here but with flat tappets at 3/4 turn preload.
Icetech said:
some of the lifters don't seem to bleed down
Click to expand...
I had the opposite problem, my lifters would bleed off completely in a matter of minutes. I ended up backing the rockers completely off, pulling the distributor so I could run the priming rod until the lifters being adjusted were rock solid, then adjusting the preload starting from the point where I can feel the pushrod getting tight. Before this I was trying to judge when all up/down motion was out and calling that zero preload but that was wrong wrong wrong apparently. When I was finished none of the pushrods would spin when I had the lifters pumped up. 90% of my valve noise is now gone.

The lifters still bleed down but they pump up with just a little extra noise at startup so I will just have to live with that.

I've still got a little bit of tapping but am unsure if that's caused by a few pushrods that are marginally long enough so I've got a set ordered that is 1 turn longer that should take of that concern so if it's still noise after that it'll be an exhaust leak.

Of course it seems like everything I've done to this car has been at least 3x as difficult as it should have been.
 
Icetech said:
K.. so i tend to overthink and make myself nuts.. my 318 has a roller cam with oem lifters, trick flows and mancini 1.5 aluminum rockers. I have had valve noise that i have been chasing i have lashed the valves 3-4 times now 1/2 turn 1 and now 1 1/2 turn a full turn should be .040 so right now i should be at .060 preload.. doing searches i see guys saying .020 is plenty, mine at .020 sounds like a slant 6 that was never taken care of.. And i see posts saying .080-.090.. i don't want to go that tight really..

So at .060 the noise is there but it's pretty quiet, the sound is uniform and not like 1-2 lifters clattering so it's probably fine. One thing annoying me though was when lashing some of the lifters don't seem to bleed down, like 1/2 turn and i hit resistance and had to put some decent pressure to get the 1.5 turn in.. My main question is will they basically self adjust the oil in the lifter on startup even if they sat for 2 months and some didn't bleed down? I have no popping in the exhaust or intake so no valves being held open at all. I just want to verify.. and next time i am 100% going solid, no guessing and preload **** :)

Only other issue now is my carb is still crazy rich at idle, like melt my eyes out rich. Gonna take it apart to check float levels at a later date, and get a pressure gauge to check pressure, have read that the street demon doesn't like a lot of pressure.
Click to expand...
Burning your eyes? What's your fuel pressure? and what kind of a carb? Also, what brand and heat range of plugs.
 
Uncle Bob said:
Of course it seems like everything I've done to this car has been at least 3x as difficult as it should have been.
Click to expand...
yeah, i have never had any problems like i'm having with this one... I don't think i have gotten 100x stupider in the last 20 years but it seems like it.. only difference is i have never run a small block before.. right now i have valve noise, a wobbling distributor and a carb to straighten out.. just **** to fix.. the dist bugs me most of all.. second one i have put in that wobbles.. first one had .015 runout in the shaft. Gonna check this one when i get home. Praying it's not the dist drive as that ****** wasn't cheap
 
toolmanmike said:
Burning your eyes? What's your fuel pressure? and what kind of a carb? Also, what brand and heat range of plugs.
Click to expand...
No pressure gauge yet, Street demon which are very pressure sensitive.. And autolite 2964s. I will work out the carb thing. just gotta get to it. Gonna work on some **** when i get home tonight.
 
Icetech said:
No pressure gauge yet, Street demon which are very pressure sensitive.. And autolite 2964s. I will work out the carb thing. just gotta get to it. Gonna work on some **** when i get home tonight.
Click to expand...
Mine runs about 5-6 PSI and so far so good. In fact, I need to go down 1 metering size to fatten it up a tad.
 
Icetech said:
No pressure gauge yet, Street demon which are very pressure sensitive.. And autolite 2964s. I will work out the carb thing. just gotta get to it. Gonna work on some **** when i get home tonight.
Click to expand...
Autolite 2964? I think that's a Chevy plug. Something Trick Flow recommended? I was running Autolites in my 273 and they were way too cold. Idled like crap with unburned fuel. On a different note, a friend's Super Bee was running rich. The stock fuel pump was putting out around 8# He tried a couple different carbs and a ton of tuning before he checked the pressure. A regulator set to 5# fixed that issue.
 
Yeah.. this pic is just from idling... and a few revs (less than a hour in total time on them), it even flooded a bit just from me spinning it to do lash last night. I figure the cheap pump is probably doing 8-9psi. I am gonna order a gauge. I really didn't want to run a regulator as i like the stock line routing and don't think i can just put a regulator up on the intake. also these demon carbs are known to have bad float settings out of the box and ****. It's on the list.. might pull it apart to check it all out tomorrow.

P.S. before someone says it.. there is no oil smoke from this car at all.. those are just fuel wet

2024-08-01 17.43.43.jpg
 
Icetech said:
Yeah.. this pic is just from idling... and a few revs (less than a hour in total time on them), it even flooded a bit just from me spinning it to do lash last night. I figure the cheap pump is probably doing 8-9psi. I am gonna order a gauge. I really didn't want to run a regulator as i like the stock line routing and don't think i can just put a regulator up on the intake. also these demon carbs are known to have bad float settings out of the box and ****. It's on the list.. might pull it apart to check it all out tomorrow.

P.S. before someone says it.. there is no oil smoke from this car at all.. those are just fuel wet

View attachment 1716300154
Click to expand...
You cannot read plugs at idle. They always read fat then.
 
Icetech said:
Yeah.. this pic is just from idling... and a few revs (less than a hour in total time on them), it even flooded a bit just from me spinning it to do lash last night. I figure the cheap pump is probably doing 8-9psi. I am gonna order a gauge. I really didn't want to run a regulator as i like the stock line routing and don't think i can just put a regulator up on the intake. also these demon carbs are known to have bad float settings out of the box and ****. It's on the list.. might pull it apart to check it all out tomorrow.

P.S. before someone says it.. there is no oil smoke from this car at all.. those are just fuel wet

View attachment 1716300154
Click to expand...
8-9 Yep. Anything over 5 will get you in trouble.
 
RustyRatRod said:
The correct way to read is go for a full throttle blast, come off the gas and kill the ignition. Stop and read them then.
Click to expand...
yeah, knew that.. i just had pulled those when doing some other **** and was surprised how black they are.. i'll iron it all out.. just bored at work with all this **** in my head, today is a day i wish i was home tearing into it :) instead of sitting here doing nothing
 
Icetech said:
yeah, knew that.. i just had pulled those when doing some other **** and was surprised how black they are.. i'll iron it all out.. just bored at work with all this **** in my head, today is a day i wish i was home tearing into it :) instead of sitting here doing nothing
Click to expand...
Getting paid to play on FABO? I wish! :poke: :rofl:
 
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