Seafomed and now its worse.......
08-25-2009, 09:15 PM
#41
Melting Slicks
A mechanic, using a TECH2 can look at the long term and short term fuel trim values...At idle, they should be between -8 & +8. If they are greater than -8 & +8, then bring the engine up to between 2500-3000 RPM's...If the fuel trims come back to the -8 & +8 range, there is a vacuum leak...
08-25-2009, 11:20 PM
#42
Racer
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bring ur car by and ill hook the hptuners up and see what ur fuel trims are at. Finding a vac leak is not hard.... we can inspect all ur connections and see if its leaking.. if not i got some carb cleaner we can spray to look for bubbling/ suction.
Anyways, bring ur car over and we can do plugs and ill use my long screwdriver to listen where the ticking is coming from (the real mechanics stethoscope)
Also wanna hear that xpipe that i sold ya.
Anyways, bring ur car over and we can do plugs and ill use my long screwdriver to listen where the ticking is coming from (the real mechanics stethoscope)
Also wanna hear that xpipe that i sold ya.
Last edited by froman; 08-25-2009 at 11:23 PM.
08-26-2009, 08:26 AM
#43
Drifting
Ok, assume that you have a certain airflow through the vacuum leak (these #'s are just for example and not representative of actual airflows), lets say 10 CFM...The car idles with 50 cfm through the TB...That means that 20% of the intake air is unmetered, which will result in a lean condition, which the STFT & LTFT tries to compensate for. You then raise the RPM to 3000. The vacuum leak goes up a bit, to 20cfm, and the TB sees 300cfm...Now, the vacuum leak represents only 7% unmetered air. The vehicle will now run less lean, requiring less LTFT & STFT correction...
08-26-2009, 09:22 AM
#44
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bring ur car by and ill hook the hptuners up and see what ur fuel trims are at. Finding a vac leak is not hard.... we can inspect all ur connections and see if its leaking.. if not i got some carb cleaner we can spray to look for bubbling/ suction.
Anyways, bring ur car over and we can do plugs and ill use my long screwdriver to listen where the ticking is coming from (the real mechanics stethoscope)
Also wanna hear that xpipe that i sold ya.
Anyways, bring ur car over and we can do plugs and ill use my long screwdriver to listen where the ticking is coming from (the real mechanics stethoscope)
Also wanna hear that xpipe that i sold ya.
The x-pipe sounds good...considering everything else is stock.
08-26-2009, 06:08 PM
#45
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You must be older than dirt. Back when airliners had multiple level reciprocating engines of up to about 30 cylinders, they also had water injection for take off position on the throttles. Little boost of power and a lot of cleaning in that high temperature atmoshpere. Have not had anyone mention that for a long time. Turbine guys think you are nuts. Old guys rule.
08-26-2009, 06:23 PM
#46
Tech Contributor
You must be older than dirt. Back when airliners had multiple level reciprocating engines of up to about 30 cylinders, they also had water injection for take off position on the throttles. Little boost of power and a lot of cleaning in that high temperature atmoshpere. Have not had anyone mention that for a long time. Turbine guys think you are nuts. Old guys rule.
08-26-2009, 09:26 PM
#48
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On the old recips, it kept cylinder head temps down as well as clean the combustion chamber.. Didn't remember the early turbines keeping that option. thanks. never know who you meet or what you can learn on this forum.
08-26-2009, 09:35 PM
#49
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08-27-2009, 12:04 PM
#50
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Froman had something come up with work yesterday and I wasn't able to make it to his place to do some investigating...but I have noticed that the ticking has almost completely went away once the car has warmed up and been driven. I have an 8 mile trip from work to the house, when I got home yesterday I popped the hood to see how bad the ticking was and it was virtually gone...any thoughts? When I start it in the morning it still ticks though.
08-27-2009, 12:41 PM
#51
Safety Car
Froman had something come up with work yesterday and I wasn't able to make it to his place to do some investigating...but I have noticed that the ticking has almost completely went away once the car has warmed up and been driven. I have an 8 mile trip from work to the house, when I got home yesterday I popped the hood to see how bad the ticking was and it was virtually gone...any thoughts? When I start it in the morning it still ticks though.
Ed
Last edited by C5XTASY; 08-27-2009 at 01:45 PM.
08-27-2009, 12:46 PM
#52
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08-27-2009, 01:35 PM
#53
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St. Jude Donor '09-'10-'11
You must be older than dirt. Back when airliners had multiple level reciprocating engines of up to about 30 cylinders, they also had water injection for take off position on the throttles. Little boost of power and a lot of cleaning in that high temperature atmoshpere. Have not had anyone mention that for a long time. Turbine guys think you are nuts. Old guys rule.
I think I have you and Lucky beat on this one! I have worked on many of the old radial big guys. The biggest being the Pratt & Whitney R-4360 Wasp. This engine has 4 rows with 7 cylinders in each row for a total of 28 cylinders. The Douglass DC-6 which I have a number of hours on had the Pratt & Whitney R2800. This engine had to have water injections (part Alcohol/water) to achieve maximum take off power. This engine is supercharged and would push 62 inches of mercury boost. In psi I believe this works out to about 30 psi. Without water injections the boost was limited to 52” or about 25 psi.Man! Us old guys can’t help talking sometimes about the old days!!
08-27-2009, 02:19 PM
#54
I tried using that port and hardly got any vacum out of it? I used a hose and syringe and squirted the seaform through that port and didn't get any smoke or engine stumble. The liquid went it, so I don't think it is clogged, anyone else have a similar experience?
08-28-2009, 07:44 AM
#55
Burning Brakes
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The C5 firing order was changed and it will have a little rough idle due to the firing order change. That is normal for the C5 to have a little bump in the idle, I'm looking for the firing order in my C5 book showing what it was before and what order it is now. Good luck.
08-28-2009, 08:00 AM
#56
Tech Contributor
The C5 firing order was changed and it will have a little rough idle due to the firing order change. That is normal for the C5 to have a little bump in the idle, I'm looking for the firing order in my C5 book showing what it was before and what order it is now. Good luck.
08-28-2009, 11:15 AM
#57
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The C5 firing order was changed and it will have a little rough idle due to the firing order change. That is normal for the C5 to have a little bump in the idle, I'm looking for the firing order in my C5 book showing what it was before and what order it is now. Good luck.
