tapioca on my dipstick
02-01-08, 09:53 PM
#1
butter makes it better
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tapioca on my dipstick
found some milky crap at the top of my dipstick. Most piston guys inform me that i have a cracked head....... I then inform them that I don't have a "head". They reply "oh... thats right!"
My mechanic says it's just condensation from the cold and i might want to look at my pcv valve. What do you guys think? Thanks for your time!
My mechanic says it's just condensation from the cold and i might want to look at my pcv valve. What do you guys think? Thanks for your time!
02-01-08, 10:07 PM
#3
FB+FC=F-ME
No rats nest........does that mean nothing at all?
You need a few of the vacum hoses to keep the crankcase ventilation system working.The fuel tank vapor recovery system(charcoal canister) also plumbs through the crankcase.You need to keep the vapor system,crankcase outlet tube,crankcase ventilation valve and 2 hoses from that valve to the intake manifold.One for a vacuum signal to activate the valve(purge the crankcase) and another to actually route the vapors into the intake stream.
If you dont keep this system working,then you get what we call "lung butter".
You need a few of the vacum hoses to keep the crankcase ventilation system working.The fuel tank vapor recovery system(charcoal canister) also plumbs through the crankcase.You need to keep the vapor system,crankcase outlet tube,crankcase ventilation valve and 2 hoses from that valve to the intake manifold.One for a vacuum signal to activate the valve(purge the crankcase) and another to actually route the vapors into the intake stream.
If you dont keep this system working,then you get what we call "lung butter".
02-01-08, 10:31 PM
#5
Steve... when I picked up that motor from you, what you mentioned above was hooked up but I somehow (I don't remember why for the life of me) I removed it... Maybe when I was re-doing my engine bay...?? Anyways, I now have the lung-butter. So I'm guessing when I hooked it back up I re-did it wrong.
I'm trying to picture the routing of what you are explaining but I'm not fully familar with the terms. I'm going to snap pics tommorow.
I'm trying to picture the routing of what you are explaining but I'm not fully familar with the terms. I'm going to snap pics tommorow.
02-02-08, 09:40 AM
#7
Yes it's his old 13B 4port w/the YAW. Manifold is a 12A with an adapter plate. As for what year the manifold is, I haven't a clue or how I would go about figuring that out.
I have it routed where the center iron and the nipple off of the oil filler tube are routed into one line using a "T" nipple and then to the larger line on the charcoal canister.
The orginal mushroom looking thing, which I'm guessing is the crankcase ventilation valve is completly MIA.
I had a friend who *supposedly* knows his stuff hooked it back up this way when he helped me drop the motor.
I have it routed where the center iron and the nipple off of the oil filler tube are routed into one line using a "T" nipple and then to the larger line on the charcoal canister.
The orginal mushroom looking thing, which I'm guessing is the crankcase ventilation valve is completly MIA.
I had a friend who *supposedly* knows his stuff hooked it back up this way when he helped me drop the motor.
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02-02-08, 09:59 AM
#8
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that stuff is normal.Alot of guys have been Venting the Cap itself,and running a splash can.If you can drill the cap and get a Hose onto it,then run to a Spill container then your "tapioca" should Dissipate..after all it's only Condensation that cannot Escape.The engine heats up and down.The "crankcase" depends on the oil to Cool it.Some of the heat of the Engine creates Moisture,so to speak...so I wouldn't worry,Unless you have like a "pound of butter"!
02-02-08, 10:17 AM
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Awesome, answered a question that I didn't even have to ask. Time to go drill a hole in the filler neck. Don't worry, will pull t out so metal shavings don't get in my oil.
02-02-08, 10:48 AM
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while were on the topic, for a pcv valve to be added to our motors, the check valve(pcv valve) should be preventing flow back to the oil pan correct?, and allowing a continous flow to the lower intake? would this not create a vacvcume leak? what am i missing
02-02-08, 12:44 PM
#15
85TIIDEVIL and Steve, I can tell from the picture that your 4 port 13B is indeed a nitrided R5, as I suspected all along. 
Maybe Steve will know what type of 12A manifold you have, and whether a PCV valve would be easy or difficult to adapt to it.
The '79-'80 manifolds had a PCV valve, as did all earlier manifolds. The '81-'85 did not. They relied on a series of small vacuum lines and a purge valve. The stock rats nest in your 1st gen, if it's an '85, will have the purge valve. There is a way to hook it up so it will act like a PCV valve and suck up all the moisture causing your capuccino (that's my word for it because when you remove the oil filler cap lid...).
Also your engine will lack the oil pressure sender 'mushroom' on the rear plate under the oil filter pedestal and right next to the water temp sender. It is a blank casting there on nitrided R5 rear plates. It is for oil pressure, not venting. You don't need to worry about it because it requires an engine tear down to drill and tap a hole for a pressure sender.
On your intermediate (middle) plate, those two nipples should not be Teed together. The one on the oil filler tube is vented to the PCV valve because it is higher and steam tends to rise. Plus the oil filler tube is thin sheet metal and condenses more easily than the iron around the other nipple. The other nipple takes air into it, such as from a charcoal canister, gas tank breather, or just an air filter. It flows into the nipple on the intermediate plate, circulates down and up to the oil filler tube. Then the air goes into the PCV valve which leads into the intake manifold where vacuum sucks it into the ports for combustion. The amount of vaccum is small so it won't effect idle quality or whatever, but it is enough flow to prevent condensation.
Maybe Steve will know what type of 12A manifold you have, and whether a PCV valve would be easy or difficult to adapt to it.
The '79-'80 manifolds had a PCV valve, as did all earlier manifolds. The '81-'85 did not. They relied on a series of small vacuum lines and a purge valve. The stock rats nest in your 1st gen, if it's an '85, will have the purge valve. There is a way to hook it up so it will act like a PCV valve and suck up all the moisture causing your capuccino (that's my word for it because when you remove the oil filler cap lid...).
Also your engine will lack the oil pressure sender 'mushroom' on the rear plate under the oil filter pedestal and right next to the water temp sender. It is a blank casting there on nitrided R5 rear plates. It is for oil pressure, not venting. You don't need to worry about it because it requires an engine tear down to drill and tap a hole for a pressure sender.
On your intermediate (middle) plate, those two nipples should not be Teed together. The one on the oil filler tube is vented to the PCV valve because it is higher and steam tends to rise. Plus the oil filler tube is thin sheet metal and condenses more easily than the iron around the other nipple. The other nipple takes air into it, such as from a charcoal canister, gas tank breather, or just an air filter. It flows into the nipple on the intermediate plate, circulates down and up to the oil filler tube. Then the air goes into the PCV valve which leads into the intake manifold where vacuum sucks it into the ports for combustion. The amount of vaccum is small so it won't effect idle quality or whatever, but it is enough flow to prevent condensation.
02-02-08, 04:46 PM
#16
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02-02-08, 10:46 PM
#18
FB+FC=F-ME
Alrighty,its been a long time since I had a carbed engine setup with a smog-less vacuum nest..... so Ill have to take my best shot.I did run the bare minimum for many years and I NEVER got any goop in my filler neck.
You need the black valve to regulate the flow out of the crankcase and you need an intake vacuum source to create suction.Simply venting to the outside air wont work because the crankcase pressure is constantly fluctuating as the engine runs......sometimes its less than atmospheric, and sometimes its more than atmospheric.......think of breathing in and out of a paper bag.You need POSITIVE ventilation,which means a flow of air IN from one nipple and a flow of air OUT from another. Old V-8's do it with their opposite valve covers.....a breather going in on one side and a PCV valve going out on the other side.Our engines are similar.
The nipple down on the center iron is the inlet.The outlet of the charcoal vapor canister goes there.This is because the RX-7 has the two systems tied together,so the gas tank vapors and the crankcase vapors feed into the same valve.If you dont have a fuel tank vapor system,you should......but if not,you can fit a small breather filter to that lower nipple also.
The nipple higher up on the oil filler neck is the outlet for the crankcase vapors.Its higher up because the water vapor and other warm stuff rises to the top of the engine and forms the sludge you see under the oilcap.The outlet nipple leads to the crankcase ventilation valve.(the black plastic thing)
The valve has 3 ports....one is a big port that is the inlet from the oil filler tube.....the 2nd is the outlet for the vapors to travel into the intake manifold,directly under the carb.....and the 3rd is a smaller vacuum signal port that tells the valve when to open.You cant just hook the oil filler neck directly to the intake manifold vacuum,because you would have a large vacuum leak,especially at idle.Youd have a hell of a lot of crankcase ventilation going on though,probably too much.The ventilation valve only kicks open when there is enough manifold vacuum for the engine to run well while this "controlled vacuum leak" is present. The vacuum signal to the valve might also be a ported signal,Im not 100% sure.A ported signal is one that only applies vacuum to an item when the engine is above a certain RPM/vacuum level.This is to prevent excess vacuum leakage from affecting idle quality,when little airflow is present in the intake system.Jeff nailed it down in his post,I just didnt see it..... and for some reason I felt like typing tonite!!
BTW,my Yaw modded intake manifold is the original 84 off my GS.I couldnt find an SA intake for Paul to smooth out,so he said to just send my 84 unit.He said that when hes done with them,they are just a hair better flowing than the stock SA units, that dont have the shutter.
You need the black valve to regulate the flow out of the crankcase and you need an intake vacuum source to create suction.Simply venting to the outside air wont work because the crankcase pressure is constantly fluctuating as the engine runs......sometimes its less than atmospheric, and sometimes its more than atmospheric.......think of breathing in and out of a paper bag.You need POSITIVE ventilation,which means a flow of air IN from one nipple and a flow of air OUT from another. Old V-8's do it with their opposite valve covers.....a breather going in on one side and a PCV valve going out on the other side.Our engines are similar.
The nipple down on the center iron is the inlet.The outlet of the charcoal vapor canister goes there.This is because the RX-7 has the two systems tied together,so the gas tank vapors and the crankcase vapors feed into the same valve.If you dont have a fuel tank vapor system,you should......but if not,you can fit a small breather filter to that lower nipple also.
The nipple higher up on the oil filler neck is the outlet for the crankcase vapors.Its higher up because the water vapor and other warm stuff rises to the top of the engine and forms the sludge you see under the oilcap.The outlet nipple leads to the crankcase ventilation valve.(the black plastic thing)
The valve has 3 ports....one is a big port that is the inlet from the oil filler tube.....the 2nd is the outlet for the vapors to travel into the intake manifold,directly under the carb.....and the 3rd is a smaller vacuum signal port that tells the valve when to open.You cant just hook the oil filler neck directly to the intake manifold vacuum,because you would have a large vacuum leak,especially at idle.Youd have a hell of a lot of crankcase ventilation going on though,probably too much.The ventilation valve only kicks open when there is enough manifold vacuum for the engine to run well while this "controlled vacuum leak" is present. The vacuum signal to the valve might also be a ported signal,Im not 100% sure.A ported signal is one that only applies vacuum to an item when the engine is above a certain RPM/vacuum level.This is to prevent excess vacuum leakage from affecting idle quality,when little airflow is present in the intake system.Jeff nailed it down in his post,I just didnt see it..... and for some reason I felt like typing tonite!!
BTW,my Yaw modded intake manifold is the original 84 off my GS.I couldnt find an SA intake for Paul to smooth out,so he said to just send my 84 unit.He said that when hes done with them,they are just a hair better flowing than the stock SA units, that dont have the shutter.
02-03-08, 01:00 PM
#20
So I looked at my orginal 12A, which is still completly stock and intact as a reference, and the upper nipple, the one on the oil filler tube is routed to a "T" which splits to the crankcase vent solenoid / 1st pic, and then to the fuel bowl vent solenoid outlet / 2nd pic. Should I do the same...???
I'm putting pics to make it super clear what I'm talking about.
I'm putting pics to make it super clear what I'm talking about.
02-03-08, 01:49 PM
#21
According to my unmolested 12A, coming off of the crankcase vent solenoid, the top nipple goes to the nipple on the left and down of the mixture screw...
and the smaller bottom nipple on the crancase vent solenoid goes to the nipple right of the mixture screw.
*I circled them which is kinda hard to see but they are there.
and the smaller bottom nipple on the crancase vent solenoid goes to the nipple right of the mixture screw.
*I circled them which is kinda hard to see but they are there.
02-03-08, 02:42 PM
#22
FB+FC=F-ME
That should work fine.
Tee'ing in the carb vent bowl just adds another vapor recovery system to the works.That is,the valve is now drawing in waste vapor from the gas tank,crankcase and float bowl of the carb.
Your setup looks good,now just drive it a bunch and keep an eye out for more snot.
Tee'ing in the carb vent bowl just adds another vapor recovery system to the works.That is,the valve is now drawing in waste vapor from the gas tank,crankcase and float bowl of the carb.
Your setup looks good,now just drive it a bunch and keep an eye out for more snot.
02-03-08, 04:37 PM
#25
So what is nessacary to make it vent correctly again? I have this lung butter too and I recently had a engine swap with no rats nest, no charcoal canister. The only vaccum source is the vacuum advance and the brake booster hose. I have a GSL-SE 13b with a sidedraft mikuni with gslse lower intake. What would I need to do to make it vent correctly??