| Slant Six Forum https://slantsix.org/forum/ |
|
| 225 tuning issues... https://slantsix.org/forum/viewtopic.php?t=19101 |
Page 1 of 2 |
| Author: | 64A100 [ Wed Aug 09, 2006 12:13 pm ] |
| Post subject: | 225 tuning issues... |
Alright everybody, I'm having some trouble getting the 225 in my A100 to run like it should. Basically, the running issues I have are, at cold start; slightly rough idle, black smoke in exhaust. It takes a while to warm up, but once it's warm, the choke opens all the way, the black smoke is gone, but there's a general loss of power throughout the rpm range, and just doesn't feel like the motor's running as well or as smooth as it should. Having trouble dialing this one in. This is what I've done: First, the compression tests great on this motor. Total rebuilt distributor, points set to spec. (.020) New plug wires. Plugs gapped to spec. Checked jet size, is at spec. (53) New fuel filter. Checked and set the float height setting to spec. (27/32") Can't seem to find a spot in the mixture adj. where this motor will idle smooth and run like it should at speed. I have a '64 A100, Auto trans., 225 slant6, Holley fact. rebuilt #1920 carb. Timing is set to 3 deg. BTDC. (A little adv. for modern gas). Total advance at around 3000 rpm. is 30 deg. (as per spec.) I'm fairly new to these motors, so any help or suggestions, would be great. The only thing I can think is carburetor. Maybe spark plug type? Let me know what you guys think. Thanks |
|
| Author: | SlantSixDan [ Wed Aug 09, 2006 1:37 pm ] |
| Post subject: | Re: 225 tuning issues... |
Quote: fact. rebuilt #1920 carb.
Probably causing most or all of your problem. "Remanufactured" ("factory rebuilt") carburetors are junk.
|
|
| Author: | Eric W [ Thu Aug 10, 2006 12:15 am ] |
| Post subject: | |
Dan is correct on the "remanufactured" carburetors. You usually have to rebuild them yourself to get them right. First, sounds like you need to get your choke adjusted properly. Have a manual to help with this? Second, get rid of the #53 jet. Try to go two or three steps richer, up to a 56 or so and see if that helps your lose of power. In other words, your to lean. Bump your timing up some to. Slants like that. 
|
|
| Author: | Todd360 [ Thu Aug 10, 2006 3:45 am ] |
| Post subject: | |
Did you adjust the valves with the motor up to temperature and running? I had similar problems such as you described with my 66 Dart. After adjusting the valves to factory specs (.010 intake and .020 exhaust-I think- someone please correct me if I'm wrong) my engine smoothed out and ran 100 percent better. Good Luck Todd |
|
| Author: | DusterIdiot [ Thu Aug 10, 2006 7:26 am ] |
| Post subject: | Yep...and... |
If you haven't checked your timing chain in a while, pull the cap off the distributor...roll the crank back and forth and watch the rotor if you can move the crank forward then back and the rotor takes a while to follow suit...then your timing chain needs replacing...this can cause all sorts of fun running problems, and stall outs. I concur with the carb...minimum #56...#58 would be better for the jetting...hopefully all the other circuits work OK.... -D.Idiot |
|
| Author: | Doctor Dodge [ Thu Aug 10, 2006 10:19 pm ] |
| Post subject: | |
Vote #2 for a valve adjustment, my bet is that there are some tight exhaust valves. DD |
|
| Author: | VDART [ Fri Aug 11, 2006 5:56 am ] |
| Post subject: | |
vote #3 adjust valves 1st before other sleuthing is done |
|
| Author: | 64A100 [ Fri Aug 11, 2006 11:58 am ] |
| Post subject: | valve adj. |
Thanks for the replies, I did adjust the valves to fact. spec. with the motor hot, right before digging into the tuning problems. Just out of curiosity, what are the best spark plugs to run in a stock 225 slant? |
|
| Author: | emsvitil [ Fri Aug 11, 2006 12:51 pm ] |
| Post subject: | |
With the spark plug tubes, you want extended tip spark plugs. Autolite 985 is an example, and are cheap. There are NGK's which I don't remember the number of, but bet that Dan has memorized.....  (and probably a few others too)
|
|
| Author: | SlantSixDan [ Fri Aug 11, 2006 12:56 pm ] |
| Post subject: | Re: valve adj. |
Quote: Just out of curiosity, what are the best spark plugs to run in a stock 225 slant?
For the spark plug tube type heads, use NGK type ZFR5N, which is an excellent and inexpensive spark plug used on many late-model Mopars (ask for plugs for a 2000 Jeep Cherokee with 4.0 six-cylinder engine if your NGK parts source won't take your order by part number.) These plugs will take a smaller spark plug socket wrench than you're used to using (5/8" rather than 13/16").Remember, if your head is a '63-'74, you need to remove the metal ring gaskets from the plugs before installing them. |
|
| Author: | 64A100 [ Fri Aug 11, 2006 3:26 pm ] |
| Post subject: | Not there yet... |
Just soldered and drilled out the jet to a #56, Noticed while I was at it, that the bowl vent opening looked big, checked that and set it to spec. (1/16"). Once back on the car, I reset idle to 550 rpm, and readjusted the mixture. What happened was the best cold start and curb idle I've had so far, but on acceleration, it's bogging down and backfiring through the carb. Any ideas? |
|
| Author: | SlantSixDan [ Fri Aug 11, 2006 4:18 pm ] |
| Post subject: | |
See my first response, up above. I think you are beating a dead pony (carburetor). 550 is spec but too slow, BTW. Try 650. |
|
| Author: | Charrlie_S [ Fri Aug 11, 2006 6:48 pm ] |
| Post subject: | |
Are you still running points? If the dwell is not correct, that can cause a backfire, similar to a poor accelerator pump shot. Also check for a worn out distributer shaft upper bushing. That can cause the dwell to be inconsistant between cylinders, and can only be detected with a scope or distributer machine. |
|
| Author: | Eric W [ Sat Aug 12, 2006 12:19 am ] |
| Post subject: | |
Agree with Charlie, sounds like you also have some timing issues. In addition to checking dwell, check for clean points contatacts. Might be a good time to convert to a Pertronix electronic ignition. I use the NGK plugs in my engine and they run cleaner than the Autolite 56's previously used. Another cause for your backfiring could be the carb is still a little to lean. Try a #58 and see what happens after looking at your distributer. |
|
| Author: | Sam Powell [ Sat Aug 12, 2006 6:04 am ] |
| Post subject: | |
This is the first time I have heard of removing the gasket ring from the plugs. Could you please elaborate on this a little. How did I miss this all these years? Sam |
|
| Page 1 of 2 | All times are UTC-08:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|