Engine Problems:PT2-can't set lash-Oil leak.
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Drifting
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Engine Problems:PT2-can't set lash-Oil leak.
Today I droped my oil pan about a 1/2 inch and coated the timing cover and oil pan in HIGH temp RTV sealant just on the front where it was leaking. And then put it all back together with my Fel-Pro 1 peice gasket. Let it settle and dry for an hour and started her back up. It drips about once every 5-6 seconds. Just one little bastard drip! Talk about irritation.
I have my timing set at 12deg@1,100rpm w/out vac.adv. Set the idle/air and the float. The motor still dropped REAL low in gear. I haven't hooked a vac gauge up to it yet. (I'm rebuiling a X-fire for a friend at the time too so that took up most my energy)
I went to set the last...But the open headers held me back from setting the lash by making it "tick". So, I'll have to figure out a way to get some kind of muffling going on.
It's still an irritation. Can't seem to get stuff right. Something has always got to be just a "tad" off from what it needs to be. :cuss
I have my timing set at 12deg@1,100rpm w/out vac.adv. Set the idle/air and the float. The motor still dropped REAL low in gear. I haven't hooked a vac gauge up to it yet. (I'm rebuiling a X-fire for a friend at the time too so that took up most my energy)
I went to set the last...But the open headers held me back from setting the lash by making it "tick". So, I'll have to figure out a way to get some kind of muffling going on.
It's still an irritation. Can't seem to get stuff right. Something has always got to be just a "tad" off from what it needs to be. :cuss
Drifting
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From: Honolulu Hawaii
Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
Aaron
I was wondering what happened over the weekend? Thanks for the follow-up post.
Try cranking the timing up higher than 12 deg (like 16) and THEN back the idle rpm down to 800 rpm. The timing should also drop as the idle rpm drops. Then set for 12 deg at the lower idle.
Hook up the vacuum gauge and look at the needle, if steady, your valve adjustment should be ok.
I was wondering what happened over the weekend? Thanks for the follow-up post.
Try cranking the timing up higher than 12 deg (like 16) and THEN back the idle rpm down to 800 rpm. The timing should also drop as the idle rpm drops. Then set for 12 deg at the lower idle.
Hook up the vacuum gauge and look at the needle, if steady, your valve adjustment should be ok.
Safety Car
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From: Fountain Hills AZ
Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
RTV doesn't always work so well if the surfaces aren't completely oil free. Also, until it sets up enough, warm engine oil can disolve it. Ideally, let it set up overnight before running the engine. I agree with Nunus on the timing. At 1100 rpm you may be already getting some centrifugal advance and you may not be reading the actual initial advance. I prefer to set timing to total first and then adjust the curve to get the initial where I want it.
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Drifting
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Re: Engine Problems:PT2-can't set lash-Oil leak. (nunus79)
I set it at 12@1100 and then backed the idle down...
So now I should set it at 16-18@1100 and then back it the idle down to 800 and it should be near 12deg?
I'll throw a gauge on there tomorrow after work and see what it's looking like. Do I need a reading from "D" or parked??
If the vacuum is low, what does that point to? a leak?
So now I should set it at 16-18@1100 and then back it the idle down to 800 and it should be near 12deg?
I'll throw a gauge on there tomorrow after work and see what it's looking like. Do I need a reading from "D" or parked??
If the vacuum is low, what does that point to? a leak?
Thread Starter
Drifting
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Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
I'm going to have to set my lash again on some of them. I noticed a little ticking after I tried to do it and had alread put the cover back on. So, I'll set the last back tomorrow.
If I set it to 16 deg at a higher RPM, drop the idle down and then set it back to 12deg at 800...wouldn't it be easier to just set the timing at 800 instead of jacking it up to set it back down? Or am I missing a point here?
I have no idea how to set my advance curve. I was told to get some lighter springs, go to the track and change one spring to lighter and lighter until my 60FT time stops improving. And then change the other spring to lighter and lighters until my 1/4 stops improving...
Sound messsed up????? Or is that the best way to do it?
[Modified by Aaron-74, 8:47 PM 7/29/2002]
If I set it to 16 deg at a higher RPM, drop the idle down and then set it back to 12deg at 800...wouldn't it be easier to just set the timing at 800 instead of jacking it up to set it back down? Or am I missing a point here?
I have no idea how to set my advance curve. I was told to get some lighter springs, go to the track and change one spring to lighter and lighter until my 60FT time stops improving. And then change the other spring to lighter and lighters until my 1/4 stops improving...
Sound messsed up????? Or is that the best way to do it?
[Modified by Aaron-74, 8:47 PM 7/29/2002]
Drifting
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From: Honolulu Hawaii
Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
If I set it to 16 deg at a higher RPM, drop the idle down and then set it back to 12deg at 800...wouldn't it be easier to just set the timing at 800 instead of jacking it up to set it back down? Or am I missing a point here?
After you got the initial advance squared away, you got to find a way to limit your total advance (mechanical+initial) to 36 deg. Then after you do that, then play with different springs to adjust how fast that mechanical advance comes in. Too quick a curve and you'll ping. Too slow a curve and your engine will feel like a dog. Just right a curve and you'll be smoking Rustangs!! :D
Drifting
Joined: Nov 2001
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From: 68 427 4.11s Roadster
Re: Engine Problems:PT2-can't set lash-Oil leak. (nunus79)
Look on the tube/can of high temp RTV for it specificaly stating its oil proof. There is high temp and oil proof. The high temp is only 100* higher 650*?
If it doesn't say its oil proof its going to physicly change and be worse later.
You won't need to do any future oil changes since you'll be doing them every month.
If it doesn't say its oil proof its going to physicly change and be worse later.
You won't need to do any future oil changes since you'll be doing them every month.
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Drifting
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Re: Engine Problems:PT2-can't set lash-Oil leak. (nunus79)
I can idle at 500 in park if I need to. My cam is not that big at all. It's probably one of the smallest CompCams. .484/.501 262/270 110LCA. I just read in a manual of mine that I should set it at 12-15deg@1,100 rpm.
How do I find my mechanical advance?? If 12 is my initial, how do I find out I've got 24 def mechanical adv?
How do I find my mechanical advance?? If 12 is my initial, how do I find out I've got 24 def mechanical adv?
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Drifting
Joined: Jan 2002
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From: Schaumburg IL
Re: Engine Problems:PT2-can't set lash-Oil leak. (nunus79)
Hi Aaron74
There are a couple of things that you need to check.
1. What is the manifold vacuum at idle in park?
2. Squeeze off each vacuum line from the carb and see if the vacuum changes. Specifically the line for the lights, and the connection to the trans vacuum modulator.
3. Take a reading of the vacuum in DRIVE. If it is lower than the cut-in point of the PV in the carb, guess what? You start dumping fuel and idle will go to hell.
4. Pull up Lars paper on setting timing in the FAQ area. You want about 34-36 degrees all in by 3000-3500 with the initial to mechanical being a smooth transisition.
Good luck.
There are a couple of things that you need to check.
1. What is the manifold vacuum at idle in park?
2. Squeeze off each vacuum line from the carb and see if the vacuum changes. Specifically the line for the lights, and the connection to the trans vacuum modulator.
3. Take a reading of the vacuum in DRIVE. If it is lower than the cut-in point of the PV in the carb, guess what? You start dumping fuel and idle will go to hell.
4. Pull up Lars paper on setting timing in the FAQ area. You want about 34-36 degrees all in by 3000-3500 with the initial to mechanical being a smooth transisition.
Good luck.
Drifting
Joined: Nov 2000
Posts: 1,361
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From: Honolulu Hawaii
Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
How do I find my mechanical advance?? If 12 is my initial, how do I find out I've got 24 def mechanical adv?
Hook-up timing light & verify your initial advance at idle.
Rev the engine and watch the timing mark climb.
The point at which the timing mark stops climbing is your total advance.
Subtract the initial advance from the total advance.
The difference is your mechanical advance.
Drifting
Joined: Jan 2002
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From: Schaumburg IL
Re: Engine Problems:PT2-can't set lash-Oil leak. (Aaron-74)
If your carb is a stock Holley (no one has massaged it) they put a 6.5" PV in. If you are pulling less than 6.5" in drive at idle the PV is starting to put gas into the mains. Anther way if you don't know is to pull the primary float bowl and look at it.
Jim
Jim
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From: Fountain Hills AZ
Re: Engine Problems:PT2-can't set lash-Oil leak. (nunus79)
If I set it to 16 deg at a higher RPM, drop the idle down and then set it back to 12deg at 800...wouldn't it be easier to just set the timing at 800 instead of jacking it up to set it back down? Or am I missing a point here?
I assumed that 1100 was the lowest that you could idle at because of your cam. Advancing to 16 would have allowed you to drop the idle lower to 800 and keep your idle quality. If you can idle at 800 in "park" then just set the timing to 12 degs at 800 rpm. Cammed engines like/need a little bit more initial advance than stock engines. 12 deg @ 800 is just a starting point. You will probably find that your engine runs/responds better at even higher inital advance. Of course the trade off to watch out for is pinging with the higher advance.
After you got the initial advance squared away, you got to find a way to limit your total advance (mechanical+initial) to 36 deg. Then after you do that, then play with different springs to adjust how fast that mechanical advance comes in. Too quick a curve and you'll ping. Too slow a curve and your engine will feel like a dog. Just right a curve and you'll be smoking Rustangs!! :D
I assumed that 1100 was the lowest that you could idle at because of your cam. Advancing to 16 would have allowed you to drop the idle lower to 800 and keep your idle quality. If you can idle at 800 in "park" then just set the timing to 12 degs at 800 rpm. Cammed engines like/need a little bit more initial advance than stock engines. 12 deg @ 800 is just a starting point. You will probably find that your engine runs/responds better at even higher inital advance. Of course the trade off to watch out for is pinging with the higher advance.
After you got the initial advance squared away, you got to find a way to limit your total advance (mechanical+initial) to 36 deg. Then after you do that, then play with different springs to adjust how fast that mechanical advance comes in. Too quick a curve and you'll ping. Too slow a curve and your engine will feel like a dog. Just right a curve and you'll be smoking Rustangs!! :D
