My First Tune up

[dcarlg]

I'm ready to tune-up my stock Tricarb after researching this forum and reading the article by Norman Nock, Dudley Haines and Reid Trummel in Tech Talk.
Although I have owned the car for 4 decades, this task was previously outsourced.

Some quick questions:
1. Does the light bulb trick for static timing work on Pertronix ignition?
2. Should I remove the balance tube between the carbs and plug the ports before adjustments?
3. Using the Colortune, what is my target color?

The SU carb tool kit should arrive tomorrow. I'll start with the valves today.

Thanks.
Douglas

[Healey Nut]

As the saying goes .....If it aint broke dont fix it !!!!!!!!!

[steveg]

I'm ready to tune-up my stock Tricarb after researching this forum and reading the article by Norman Nock, Dudley Haines and Reid Trummel in Tech Talk.
Although I have owned the car for 4 decades, this task was previously outsourced.

Some quick questions:
1. Does the light bulb trick for static timing work on Pertronix ignition?
2. Should I remove the balance tube between the carbs and plug the ports before adjustments?
3. Using the Colortune, what is my target color?

The SU carb tool kit should arrive tomorrow. I'll start with the valves today.

Thanks.
Douglas

1. Call Pertronix in San Dimas or LaVerne CA and ask - I doubt it.
2. No
3. Bunsen blue toward yellowish

[dcarlg]

As the saying goes .....If it aint broke dont fix it !!!!!!!!!

I also like the old saying "If you want to keep it, maintain it."
Deciding which philosophy to apply is a constant challenge.

[Drone Dog]

Douglas
i too have a tri-carb and just put my engine together. First is your car running rough now?

1) if your car is running i don't see a need to static time it. Go to HF or some other place and buy a timing gun if you don't have one. they are not that expensive and you can set the advance on the gun (15*BTDC). i only used static timing to get mine started that first time. and for that i used points and condenser. then switched back to pertronix.

2) i left my balance tube in place while making my adjustments. are you thinking this for adjustments to the fuel mixture and carb balance? i set all my jets the same depth below the bridge (2 turns and then usd a depth gauge to make sure they were all the same), i just tried using a colortune plug for the first time. not real sure it was a big help. just more of a confirmation. But when i adjusted the front carb, each adjustment i made i made to all carbs at the same time because of the balance tube. then i rebalanced the carbs and checked the mixtures again. but i left the balance tube in place the whole time.

3) on the colortune plug, i took it to all blue but then made the mixture a little richer until i was getting flashes of yellow. i think maybe some of the flashes were because of the way the plug wire sits on the plug. not a great connection. i would get a couple of flashes of yellow and then blue. so i got to a point of some yellow and blue and went with that. i never did see the orange as in the videos.

after driving the car i felt it was running hotter (my engine has just been rebuilt with less than 500 miles) so i lowered my jets one more flat. tonight i took it out again, it is running a little cooler. Although it is tougher to start when cold than before the colortune setting. after i try this setting for a while i may try one more flat lower if the cold start does not improve.

if your engine runs cooler, you may be able to go leaner right from the start. if you have your breathers off you can also do the lift test. And... also do some hot runs, then read your plugs.

having said all this i will tell you the one thing i have read on more than one forum with different cars. "the biggest problem people have with SU carbs is they don't leave them alone". once i get mine set where i feel comfortable i hope not to mess with them again.

in other words if your car runs fine after the valve adjustment and timing being set, i would leave the carbs alone.

if you are having issues past that, i would check the floats/needle valves, and the float levels before anything else. then balance, and then colortune, in that order. if the car runs fine after either step, i would stop.

there are certainly people here who have more experience than myself and can probably give better advice.

one thing, once you get everything working as you like.... if you ever pull the tops of the carbs off, i would be interested in how deep your jets are below the bridge and all the steps you did for your tune up. please follow up here. i would enjoy the info.

oh one last thing i would check before doing too much to the carbs. i would make sure my linkage is still balanced. and remember to rebalance your linkage after any changes carb balancing. each time you change the idle screw setting you change when the linkage picks up the throttle.

Good luck
TL

[roscoe]

I prefer " If it ain't broken, then break it". My shorthand for commencing a job without the complete knowledge, tooling, or skill to complete said task. On the one hand it takes you longer. On the other hand when you're done you know what you have and what to avoid next time. Hopefully the expensive bits will still be good and you will have zero parts remaining on the bench. You have also prompted me to commence an overdue tune up on my car. That cork valve cover gasket on the shelf is getting dusty and stiff.......thanks loads.

[dcarlg]

Drone Dog, I've been following your posts closely, trying to learn. My car runs pretty well, but is hard to start without ether and warbles a bit when coasting. Also, the co-pilot complains of strong odors. I think the middle carb is running rich, after looking at the spark plugs. Besides, I want to try out my HF timing light and Colortune. Both are unused.
I'll post progress and results.

Jon, I had left-over bits when I reassembled my transmission once. Needed to start over.

[mgtf328]

I've just been thru all this with my BJ8. See "Carb tune" post. Yes, I know, only 2 carbs! I found mine ran better when I increased the plug gap by 5 thou (inches) as recommended by Petronix and it likes to run on the rich side.
Have you checked all the chokes close fully and evenly when you push the choke back in. When I had a starting problem I found that the choke wasn't set properly, the jets didn't go down far enough when I pulled the choke out. I renewed the cables and adjusted them, one cable was longer than the other an it was rather difficult to get the chokes to open equally. When it's correct a small amount of fuel is pumped out of each jet when the jets go down, that didn't happen on mine. When I got it right it started ok.
AJ

[Drone Dog]

well if it is any help, my jets are set .071 below the bridge. that is about 1 flat past two full turns on the mixture nuts for my car. and one flat more than i felt the colortune plug wanted me. my car actually idled best after the colortune plug adjustment and ran really nice. but i would rather be a little rich at this point with my engine temps.

check your float chambers. make sure nothing is sticking there and they are set properly.

Agree also with AJ on plugs and choke setting. i think my plugs are gapped .032 actually. the choke cables on these things are crazy. i am not sure i have my choke set up like it should be. plan to work on that next.

[Jack T]

As the saying goes .....If it aint broke dont fix it !!!!!!!!!

Oh. I thought it went "If it ain't broke, fix it again". Now i know what i've been doing wrong.

[dcarlg]

OK, valves are now adjusted to .012" cold. They were mostly tighter. I used the Rule of 13, then rechecked them.
New spark plugs gapped at .032" and installed. NGK BPR6ES. I found that some suggest .030", some .035" with Pertronix ignition and Flamethrower coil.
Magnecor wires retained. I'll look under the hood for sparking while the engine runs after dark.
Found and fixed a vacuum leak.
The jets had returned to the up position after I pushed the choke back in, as designed.
Onto the carbs tomorrow. The SU Carb Tool Kit has not arrived yet.
Besides, tonight is Pub Night for the SE Michigan AH Club and I'll drive the Tricarb there.
Regards.
Douglas

[Keoke]

OH! An adjustable timing light from Sears should be cheep right now?

[dcarlg]

Updates!
Previously, I fixed the vacuum leak which helped with cold starts and diminished the popping exhaust when coasting.
Today I checked the timing with my HF timing light with adjustable advance. It was set at 18 degrees BTDC. Changed to 15.
Removed dashpots and pistons. Needles were centered and shoulders flush.
The jets were recessed: #1 at .079", #2 at .099", #3 at .098". (Drone Dog requested this data.)
Maybe that's why the co-pilot was complaining about odors! Too rich.
I reset them to .076" and reassembled the carbs.
Then I fiddled with the SU Carb Tool Kit, but the carbs seemed synchronized.
Moving on to the Colortune, I leaned out each carb 4 or 5 flats to achieve mostly blue with a little yellow.
Adjusted the idle to 750 RPM plus or minus.
Will try the lift pin method, then a test drive later.
My Tricarb now starts easier, has reduced popping while coasting and less run-on during shut down. Hope the fumes are diminished too.
I learned to use the timing light gun, SU Carb Tool Kit and the Colortune, set the mixture and the idle.
Thanks for sharing your knowledge and patiently giving me advice.
Happy Father's Day to all!
Regards.
Douglas

[Michael Oritt]

"Also, the co-pilot complains of strong odors. I think the middle carb is running rich"

It is easier and much cheaper to adjust the carb's mixture than to change the co-pilot.
I second your exploring carb adjustment and ignition timing setting, etc.

[Drone Dog]

With the changes, you might want to watch the engine temps and other signs of running too lean.