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- #21
Great, do I just add it and how much do I add
Gross Polluter help
- Thread starter Terry Lindsey
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"Good in life", meaning little children breathing dangerous amounts of pollutants from your tail pipe?
Marvels comes in 16 oz bottles (and larger). That's all you need. Add and run for 500-1000 miles, then change your oil.. Keep an eye on the oil, it is taking in all the pollutants that are coming off the valves and such, so you don't want to run "dirty" oil too long.
To check for sticky valves, put a piece of paper up against the tail pipe while running, if it pops or seems to get sucked back into the pipe, then you do have a sticky valve. (Exhaust valve that does not close completely will then run suction at the tail). This is a common problem with older engines and can make your HC values skyrocket.
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A does not equal B.
If your tailpipe is clean, it shouldn't matter what's under the hood. That's @SW20 point, and I concur.
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- #25
Latest update, valves were too tight so I readjusted to specs. I lowered idle to specs with slight advance to timing. No vacuum leaks or sticking valves. No hesitation good throttle response. Dang it flunked Smog again with too high HC at idle. In fact the O2 was a bit lower but HC creeped up a bit. Tech suggested re jetting to smaller size. Soooo, I pulled both primary and secondary jets. Primary was stamped 124 secondary stamped 38. Any ideas on what those numbers mean and recommendations for different sizes. As a footnote me truck is a 76 but the carb came from a 78.
spotcruiser
Geezer
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- #27
Thanks, I called SOR and they are out of stock. He couldn’t be specific but did recommend going to a smaller size primary jet. Now I need to figure out what that size should be and where to get one
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- #29
The idle circuit is functioning properly. After reviewing numerous prior threads on the issue, apparently leaning the idle mixture too much actually has the opposite effect and raises HC cuz the fuel is too lean to burn. So, I’ve enriched the fuel mixture and raised the idle to 800 and will try it again. I did a vacuum test and I’m at a steady 15 at 3,000 ft
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- #31
Kind of a story...when I leaned out the mixture it actually raised the HC a bit... not good. So, I’ve now raised the mixture and then discovered that is cap was missing from the intake manifold vacuum port. I capped that and now I’m reading a steady 15 on vacuum. Hopefully that’s okay because I’m at 3000’. Just to be even more cautious, I’m installing a new PCV valve tomorrow. I think I’ll run it for a few days and then take it back in for another attempt. Obviously, if you have any other suggestions I’m more than grateful for the input.
High HCs can be lowered by a fresh oil change (like the day you're getting it tested). New spark plugs wouldn't hurt. Drive it hard on the highway right before the emission test, so that it's very hot (or full operating temperature).
I would also put a few gallons of E85 in the tank along with 5-10 gallons of regular fuel. This adds oxygen and acts like an AIR pump on steroids. This thread shows how E-85 worked with no AIR pump at all: Using E85 to pass emissions - Rising Sun Member Forums. You can also add 'Heet' (if sold in California) a cheap source of alcohol for your fuel. After the e-test, burn up this crappy gasahol junk as fast as you can, and switch back to regular gasoline.
Still, your HCs are very high at idle, which worries me. I think you still have fuel issues or vacuum leaks. You should have a steady idle at 650-750, and low HCs. Is your AIR pump (not sure if you have one) putting out substantial amounts of air?
I would also put a few gallons of E85 in the tank along with 5-10 gallons of regular fuel. This adds oxygen and acts like an AIR pump on steroids. This thread shows how E-85 worked with no AIR pump at all: Using E85 to pass emissions - Rising Sun Member Forums. You can also add 'Heet' (if sold in California) a cheap source of alcohol for your fuel. After the e-test, burn up this crappy gasahol junk as fast as you can, and switch back to regular gasoline.
Still, your HCs are very high at idle, which worries me. I think you still have fuel issues or vacuum leaks. You should have a steady idle at 650-750, and low HCs. Is your AIR pump (not sure if you have one) putting out substantial amounts of air?
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- #34
I’ll take your advice. Yes the air pump works great. Thanks
Hey, one more thing. I see high HCs when the engine is not burning the fuel completely. This can be caused by a too low of a temperature in the engine while running. Check the coolant temperature sensor (if you have fuel injection) and the thermostat.
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- #36
Temp is correct as I use a number gauge and double checked with a laser temp gun. Carb not FI
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- #38
It’s crappy... the other day it was 16 at 3000’. Then I had started thinking that my valve adjustment was too loose. So, I readjusted the valves and now I’m at 12. It idles now at 650rpm, but I have noticed a drop in power going up hill plus it smells rich. I’m perplexed to say the least. I would be happy to get the vacuum back to 15 or 16. I can detect no vacuum leaks.!!! Plus I’m still confused about wether the air cleaner is supposed to be installed when doing carb adjustments.
I am in Arizona at 2100' . I never smell rich at all. If the valves are ok, carb basic adjust ok, then I would look for the vacuum leak. A drop in power is a big clue on a vacuum leak.
Are you sure there is no leak as my 1969 F engine reads 18-19 and has no power problem ?
Are you sure there is no leak as my 1969 F engine reads 18-19 and has no power problem ?
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- #40
Thanks for the video. I will check again but, I have no misfire, hesitation, stalling, or bad idle. My timing is set at the BB. I will hook up the tester today and see if advancing the timing does anything with the vacuum. I did not
