pwd
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Is it possible to pressurize the crankcase through the cylinder, I know that I have one cylinder that is down on compression, could this be a possible cause?
Homemade Catch Can
- Thread starter Lextreme II
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The 1UZFE EGR Delete Kit is available for sale here.
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Sure, that's what blowby is, if it's the rings that are causing your low compression.
When I'm running a leakdown test, if I have a cylinder that shows too much leakdown on the gauges, I try to find where the air is going:
1) I listen in the intake manifold to see if the air is coming out an intake valve.
2) Ditto in the exhaust pipe to see if an exhaust valve is passing.
3) I take the oil cap off and listen in the valve cover to see if it's coming from the crankcase, which would mean rings.
The leakdown test is really a great way not only to find out if the motor isn't healthy, but to isolate the problem. Leaky valves are usually a lot cheaper and easier to fix than a new shortblock, but then, with the cost of these motors, it's hardly worthwhile going into one, when a replacement motor costs less.
When I'm running a leakdown test, if I have a cylinder that shows too much leakdown on the gauges, I try to find where the air is going:
1) I listen in the intake manifold to see if the air is coming out an intake valve.
2) Ditto in the exhaust pipe to see if an exhaust valve is passing.
3) I take the oil cap off and listen in the valve cover to see if it's coming from the crankcase, which would mean rings.
The leakdown test is really a great way not only to find out if the motor isn't healthy, but to isolate the problem. Leaky valves are usually a lot cheaper and easier to fix than a new shortblock, but then, with the cost of these motors, it's hardly worthwhile going into one, when a replacement motor costs less.
pwd
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Thanks John, just makes my buying another motor OK.
At least I will have a spare motor to do something with one day.
At least I will have a spare motor to do something with one day.
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Some guys who were blowing seals from excessive blowby have not only vented both cam covers, but have vented their dipstick tubes too!
pwd
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Dumb question, but how do you go about venting the dipstick tube.
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IIRC, one guy with a Supra just pulled his dipstick out and slipped a hose over the tube, and ran the hose where it wouldn't get oil mist all over the engine bay.
I've personally seen boosted industrial engines that had so much blowby, they were blowing the dipsticks out of the tubes
I've personally seen boosted industrial engines that had so much blowby, they were blowing the dipsticks out of the tubes
had a 4age like that once, made an awfull mess of an otherwise shiny enginebay,
I have never vented the dipstick guide,
I do my catch cans with a return line towards the sump (above the normal oil level, that line also takes care of vacuming out the cranckcase from below, + the normal cover line on top, and a vacuum line towards the manifold, never let me down.
ps reading this discussion again, reminds me of having to drink large amounts of Heineken Pacco bottles, to secure enough volume to make a catch can for the 1uz! :alcoholic:
Grtz Thomas
I have never vented the dipstick guide,
I do my catch cans with a return line towards the sump (above the normal oil level, that line also takes care of vacuming out the cranckcase from below, + the normal cover line on top, and a vacuum line towards the manifold, never let me down.
ps reading this discussion again, reminds me of having to drink large amounts of Heineken Pacco bottles, to secure enough volume to make a catch can for the 1uz! :alcoholic:
Grtz Thomas
XR8tt
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I have on one engine run oil drain back from catch can to dipstick outer tube.
It solved two problems..
Bigger engines when boosted often require better crankcase ventilation ..
I find doubling from manufacturer's breathing helps.. Esp when on boost the PCV is closed, leaving in most cases one small vent ..
Strange as it may seem blow by can be due to second ring gap being too tight.. Combustion builds up between the two rings and forces both compression rings into ringlands, which also cause ring flutter at high rpm at low load.. An issue the G.M Gen lll had..
It solved two problems..
Bigger engines when boosted often require better crankcase ventilation ..
I find doubling from manufacturer's breathing helps.. Esp when on boost the PCV is closed, leaving in most cases one small vent ..
Strange as it may seem blow by can be due to second ring gap being too tight.. Combustion builds up between the two rings and forces both compression rings into ringlands, which also cause ring flutter at high rpm at low load.. An issue the G.M Gen lll had..
Is there any reason why you can't run 2 pcv's in one line?
I'm going to set up my pcv system properly after neglectling it and blowing both rear and front mains. Though I am using the factory pcv system on the left side of the engine with a new pcv it's obviously not sealing.
As opposed to making something to fix a hose to, is there any reason why I can't run a hose from the stock pcv in the valve cover, to a catch can, into a TT Supra pcv then back into manifold?
Also, got quoted $25 for a TT pcv, where do you buy simple ball and spring one way valves? Are they cheaper?
And for the record, Chris (who answers their emails) at Penrith Toyota Parts is tops. He replies quickly with PDF quotes and charges less than List price, has the customer as Soarer Club yet I've never said where I'm from.
I'm going to set up my pcv system properly after neglectling it and blowing both rear and front mains. Though I am using the factory pcv system on the left side of the engine with a new pcv it's obviously not sealing.
As opposed to making something to fix a hose to, is there any reason why I can't run a hose from the stock pcv in the valve cover, to a catch can, into a TT Supra pcv then back into manifold?
Also, got quoted $25 for a TT pcv, where do you buy simple ball and spring one way valves? Are they cheaper?
And for the record, Chris (who answers their emails) at Penrith Toyota Parts is tops. He replies quickly with PDF quotes and charges less than List price, has the customer as Soarer Club yet I've never said where I'm from.
E
ed_ma61
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you can use a std check valve from the brake booster line from any toyota at the wreckers. crappers from the 80's have metal units if thats a bonus
XR8tt
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Yep the V.L and Nissan's have them too..
Be aware running two PCV's that they "close" on boost. Or supposed too !!.. Must have another good vent to let crankcase breath..On boosted engines the std breather just keeps up. Depending on condition of engine!!
I like to have PCV to draw vacuum to rid crankcase of condensation etc.. Especially this time of the year.. One pcv and two breather's would be my choice..One from each cam cover..
The one way valves can be alittle small! Why I like to have two vents...
Be aware running two PCV's that they "close" on boost. Or supposed too !!.. Must have another good vent to let crankcase breath..On boosted engines the std breather just keeps up. Depending on condition of engine!!
I like to have PCV to draw vacuum to rid crankcase of condensation etc.. Especially this time of the year.. One pcv and two breather's would be my choice..One from each cam cover..
The one way valves can be alittle small! Why I like to have two vents...
Yeah I was planning, for now, on running one valved back to the intake manifold. And the other plumbed pre supercharger on the intake.
Is there one side that will benefit more from a catch can? Bit low on funds atm and was only going to buy one oil/air seperator etc
Is there one side that will benefit more from a catch can? Bit low on funds atm and was only going to buy one oil/air seperator etc
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I don't run any valves and haven't had any problem (boosting to 22.5psi) with blow by or blowing seals.
I do run the lines to a catch can that (one day), will be fed back to the intake.
I do run the lines to a catch can that (one day), will be fed back to the intake.
r34driftin
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What you guys are referring as a vacuum source should go directly after the air filter on the same pipe. thats if you dont just exit the pipe out under the car..
XR8tt
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I like to have at least ONE vacuum as it keeps condensation etc out of oil, helps seals also..
But MAKE sure the PCV works !! If not as said fit a one way in line valve so boost doesn't build up in crankcase..
Don't like venting atmo !! It doesn't help the polar bears..
It's not hard to run a crankcase vent to air cleaner box or pipe between filter and turbo.. Same with charcoal canister..
Keep in mind there are two vents one PCV and the other in std form rocker cover to induction / throttle body area.. It's the vac hose from rocker cover that needs to be changed or you will "boost" crankcase..
Simply remove from induction side, connect to air cleaner side where there no chance of boost.. Then block up where this hose went on induction side...
Kiora
Welcome to forums..
But MAKE sure the PCV works !! If not as said fit a one way in line valve so boost doesn't build up in crankcase..
Don't like venting atmo !! It doesn't help the polar bears..
It's not hard to run a crankcase vent to air cleaner box or pipe between filter and turbo.. Same with charcoal canister..
Keep in mind there are two vents one PCV and the other in std form rocker cover to induction / throttle body area.. It's the vac hose from rocker cover that needs to be changed or you will "boost" crankcase..
Simply remove from induction side, connect to air cleaner side where there no chance of boost.. Then block up where this hose went on induction side...
Kiora
Welcome to forums..
XR8tt
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Yep that's the way.. A 1 way valve between inlet and catch can be added ...
If there is a cover over air cleaner ?? Then the other side could go there also. It adds a barrier / shield ...
Depending on height ?? The way it's routed to assist oil drain back into engine...
I fitted a 70mm [3"] alloy tube up out of cam cover is enough to stop any oil blowing through...
If there is a cover over air cleaner ?? Then the other side could go there also. It adds a barrier / shield ...
Depending on height ?? The way it's routed to assist oil drain back into engine...
I fitted a 70mm [3"] alloy tube up out of cam cover is enough to stop any oil blowing through...
