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I've been home the past two days with a sinus infection. It's pouring rain, a good thing, so no driving today either way. However, I made no plans to drive last Saturday as Nancy and I were putting up decorations for the Christmas season. Lo and behold we finished, or at least couldn't go any further without a few things so I took off on a drive. I managed 120 miles and man is that motor something else. Very smooth. I did have an issue with the alternator light. Part way through the drive it was on but it was on very dim. At the end of the run it was a little brighter. I cut off an inch of wire and replaced the female spade connector at the alternator. I made sure to bend a 90 degree angle on the connector to ease any stress on the wire. Used friction tape to cover it all up and reattached it. Light went out and there was 12.8 volts at the battery with the car shut off and 14.2 with the car idling. Perfect.

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The miles are adding up a little at a time. I have been swamped at work and it's been either cold or wet here in the Central Valley. A few more miles (500 total)  and I'll do the first oil change and valve adjustment.

I had a clogged idle jet and we traced the problem to the thin foam filter that was included with the Knecht style air filters. Even with the foam filter properly oiled it had some bits that flaked off and made their way to the idle jet.

(Stock photo with a new filter that hasn't been properly oiled)

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I didn't think to look back to the Vintage Speed website but I discovered that the K&N #3341 filters or EMPI 3 1/2" oval K&N style filters also fit so the cheap foam filter was thrown out. K&N filters were installed after giving them a proper oiling. The filters were definitely harder to reassemble with the K&N installed but worth the fight. I took it for another spin and there seemed to be no difference in the air flow through the filter. It's nice to not have to worry about clogging the idle jets again and potentially having a fire.

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Last edited by Robert M
Bill Prout posted:

Are you using CB "Jet Dr's"?

Yes, but because the foam filter was right next to the tip of the snorkel it managed to still get in. It surprised Pat as much as it did me. The foam bit may have made it in even while I was putting the filter together some space is tight and I may have rubbed the foam across the top of the JD. 

Gordon Nichols posted:

Your K&N elements appear to much more pliable than the old K&N’s I have.  I could never bend one side in as much as that in your photo or if I did it would stay bent!  It would be nice to have a bit more flexibility in mine from time to time when putting them in and getting the cover on AND getting them sealed.

That photo was taken from the Vintage Speed website.  I did not find it to be that pliable either.   However it was not that difficult to put in.

Question: How did you know it was the idle jet? trial and error?

After my drive last weekend, I noticed a decent fuel smell in the garage. After looking everything over, I found my driver side carb gasket (gasket between carb and intake manifold) wet with gas.

I cleaned everything up this morning to find a source and I "think" it is coming from where the the fuel line connects to the carb. There are three bolts in that area... one for the fuel line, ops site side where you could mount the fuel line, and at the bottom (which I think is the carb fuel filter location?). I tighten the hose clamp a tiny bit and the other two (14mm and 19mm bolts)...

I pulled the main jets and they are clean... haven't attempted the idle jets... just curious without having to pull the whole carb out...

Side note: engine ran fine last weekend with no hesitation, no idle issues...

Thanks in advance for the help!!!

@*LongFella

Pat D came over to the house because we needed to swap out the alternator. The brand new alternator had some charging issues. I started the car and Pat said, "You have a clogged idle jet, can't you hear it?". There was a roughness to the idle I had previously attributed to the car being cold and it idled at an rpm level that was lower than normal, which again, I attributed to the engine being cold. Pat explained that with the idle jet clogged the engine would be idling lower than normal and the roughness to the idle was all because of the clogged jet. He felt around on the heads and could tell that one of the cylinders was not warming up due to the lack of fuel, thus no fire, and the cooler temperature. After removing and cleaning the idle jet we did all of them to be sure. There had also been an increase in popping during deceleration I had noticed. The hardest part is because although I had noticed all of this my inexperience wasn't telling me what I needed to know. Once it was all cleaned up the difference was night and day. I feel now that I know what I need to know and will notice if anything happens again.

Cleaning the idle jets is very easy and you should do that before anything else. However, if the gaskets between the carburetor and the manifold is wet you'll need to find the reason. It sounds like you have identified a possible source. Fuel leaking from there shouldn't have anything to do with the jets it should just be the loose fitting of the hose. If an idle jet is clogged it will do as I described earlier. It will cause your motor to idle rough and you will have an increase in popping on deceleration and you may experience backfiring. As I learned last year backfiring is bad. 

Last edited by Robert M
Robert M posted:

@*LongFella

Pat D came over to the house because we needed to swap out the alternator. The brand new alternator had some charging issues. I started the car and Pat said, "You have a clogged idle jet, can't you hear it?". There was a roughness to the idle I had previously attributed to the car being cold and it idled at an rpm level that was lower than normal, which again, I attributed to the engine being cold. Pat explained that with the idle jet clogged the engine would be idling lower than normal and the roughness to the idle was all because of the clogged jet. He felt around on the heads and could tell that one of the cylinders was not warming up due to the lack of fuel, thus no fire, and the cooler temperature. After removing and cleaning the idle jet we did all of them to be sure. There had also been an increase in popping during deceleration I had noticed. The hardest part is because although I had noticed all of this my inexperience wasn't telling me what I needed to know. Once it was all cleaned up the difference was night and day. I feel now that I know what I need to know and will notice if anything happens again.

Cleaning the idle jets is very easy and you should do that before anything else. However, if the gaskets between the carburetor and the manifold is wet you'll need to find the reason. It sounds like you have identified a possible source. Fuel leaking from there shouldn't have anything to do with the jets it should just be the loose fitting of the hose. If an idle jet is clogged it will do as I described earlier. It will cause your motor to idle rough and you will have an increase in popping on deceleration and you may experience backfiring. As I learned last year backfiring is bad. 

Thanks! Wish I had Pat D as my neighbor! I would love to job shadow him building a motor... that would be an awesome learning experience!

We just got back from a nice walk, so back to the garage I go. Will pull the idle jets and give them a good cleaning (since I am in there anyways).

I'll start it up and see if I notice a rough idle. It wasn't there last weekend...

I HATE worm hose clamps and won't use them. They cut the hose when overtightened and loosen from vibration and cause leaks and fires. Throw them in the garbage.

I had them on my old car and developed a leak at Carlisle one year. Quick fix with a screwdriver but why take a chance? The car you save may be your own.

I use spring steel clamps, they give a nice firm constant pressure. I get mine at NAPA, but they also have them in various sizes at Lowe's. It is important to get the "Goldilocks" fit as they come in many small increments.

Last edited by DannyP

 @*LongFella wrote- "... I pulled the main jets and they are clean... haven't attempted the idle jets... just curious without having to pull the whole carb out... "

As Robert said, you'll hear (and feel) the difference when an idle jet is plugged. If the air cleaners fit well and you're careful any time they're taken off and put back on it won't be a regular occurrence, but it does happen occasionally, so get used to doing it.  Do you have either the allen key or hex head type idle jet holders? They make the whole procedure way easier. And Pat D's checking for the cold exhaust tube is a great tip- that way it's not such a trial and error thing.

Btw- main jets almost never plug- they're 2 1/2- 3 times bigger than the idles and it would take a pretty big piece of crap to pull that off. Al

DannyP posted:

I HATE worm hose clamps and won't use them. They cut the hose when overtightened and loosen from vibration and cause leaks and fires. Throw them in the garbage.

I had them on my old car and developed a leak at Carlisle one year. Quick fix with a screwdriver but why take a chance? The car you save may be your own.

I use spring steel clamps, they give a nice firm constant pressure. I get mine at NAPA, but they also have them in various sizes at Lowe's. It is important to get the "Goldilocks" fit as they come in many small increments.

Me too. And I agree-- get the exact fit.

Lane:  they're color coded for different size hoses.  I can't remember the size-per-color, (Hell, I can't remember resistor color codes anymore, either!) but I know I have several different tiny bins in the shop with all of each color for standard sizes like 1/8" - 3/4" hose, usually in 1/8" increments.  Don't know if they came from Harbor Freight or elsewhere like Mechanic's Bliss, but they're out there.

Since the quality standard for pretty much anything coming from China is questionable (for both clamps and hoses), you really have to try the clamp on the hose and see how tight it feels and go from there.  They apply pressure pretty equally, so they don't have to be as tight as a Bull's butt in a cloud of flies.  I have very seldom had one leak, usually because the hose or metal tube was cruddy.

And as Danny said, they don't destroy the hose like the spiral winder clamps do (especially f you're like me and over-tighten the heck out of them in the first place).

I'm not a big fan of spiral wind clamps, either.  Best use I've found for them is to hold my heater ducts together (with no pressure) or as a balancing weight on driveshafts.....    

I only have five of the spiral wind hose clamps. The four that hold the heater duct hoses on the shroud and the heater boxes and the one on the oil breather hose. All of the fuel hoses and oil lines are AN fittings. I suppose I could find some of the spring style to replace the oil breather hose. I doubt they'd make much of a difference on the heater duct hoses since those are all a terrible fit no matter which hose I buying.  Crimping them a bit will happen with either style of hose clamp.

Last edited by Robert M
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