B&M Converter is bad

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I had the same issue once years ago on a chevy pick up. bought the truck from a family member that needed an engine. I built an engine for it and installed it. ran awesome...didnt miss a beat but as soon as you dropped it in gear it coughed right out. I fiddled with it a bunch and finally just gave the truck back to my family member because I didnt want to deal with the headache.

they ended up buying a new TQ for it and putting it in and problem solved.

not saying that is your issue....could very well be ignition related. Hard saying without being hands on with it.

a couple things I would be curious about though that dont cost money to check is....is the trans any good? (was it drivable at some point when you had it or is this all new issues since installing the new parts?) you could pull the trans pan and see if you see any particles laying in the bottom of the pan.

also I have seen guys install the TQ's wrong and force the shafts into the trans and cause damage....so you may want to keep that in mind also.

I would also try jacking the car up and get the rear wheels off the ground and then try starting it and putting in gear again and see if the issues are the same now that it is not under as much of a load and is free spinning....you can also rev it up a bit and see how things act and get it to shift gears and what not (of course make sure you have it securely on jack stands).

other than that....all the other things everyone else mentioned are good places to look. but lots of things that can be checked that wont cost you anything other than a little bit of time. good luck!
 
No fuel should be dripping in the carb at idle. Look down the throats, you see any, that needs to be resolved. Too much fuel pressure, high float level, etc.
 
Ok, so this is what I found out.

-I have no vacuum leaks
-I have no extra fuel dripping into the carb at idle
-I changed my idle to 800
-Initial timing is 13* vacuum is 1in HG @ idle

With vacuum advanced unhooked and running engine up to 3K the timing increases to 38* with it starting to advance almost immediately with the touch of the pedal.

So this is where I assume my mechanical is 25*??

I did try putting it into gear and the idle would drop to about 300 and chug.
 
I'm assuming you have a vacuum gauge because you have a reading. Bump up the initial, readjust your idle. Set your air/fuel mixture on the carb using that vacuum gauge, turn the screws out and watch the gauge, you want the highest reading you can get, and then turn them back in slightly.

Always remember timing first carb second. You are plugging the vacuum line at the carb when you unhook it, correct?

I don't recall what cam you are using but I would think you could find more than 1" of vacuum.
 
Bad Sport said:
I'm assuming you have a vacuum gauge because you have a reading. Bump up the initial, readjust your idle. Set your air/fuel mixture on the carb using that vacuum gauge, turn the screws out and watch the gauge, you want the highest reading you can get, and then turn them back in slightly.

Always remember timing first carb second. You are plugging the vacuum line at the carb when you unhook it, correct?

I don't recall what cam you are using but I would think you could find more than 1" of vacuum.
Click to expand...


When I bump up the initial my mechanical goes above the desired 38* I had the initial set to 18-20 with idle at 800 at one point and I had almost 50* with the mechanical @ 3K.

The only way I could get the 38* is to have my initial turned way down.

Yes I had the vacuum gauge plugged into the same port as the vacuum advanced. As you are looking at the Carb from the front it was on the left side.

Of course the damn timing tape flew off and crumpled up so I have to wait until I get more now. But I had it set back where I started, thank gosh.
 
Well, my teen is a stock short block with a he268h Comp cam. I run right around 18* initial. What you need to understand is you have to physically limit the mechanical in the distributor by brazing the slots or using the FBO kit, to keep your total down where you want it.

I know timing is confusing as all hell when trying to learn it, I have had to read and read some more to even begin to understand it. It took me a while, and I think that I was trying to over complicate it in my head.

You can't get the desired results until your initial is where the engine likes it AND your mechanical is limited to to keep your total where you want it. The two cannot be brought together simply by turning the distributor. Then you want to get the distributor set to allow it to come in faster. ie: lighter spring.
 
as said several time..the mechanical advance in the distributor has to be limited......so you can dial in the initial advance...

the link crackedback posted to mopar magazine articles shows how to do a stock mopar distributor...
 
70aarcuda said:
as said several time..the mechanical advance in the distributor has to be limited......so you can dial in the initial advance...

the link crackedback posted to mopar magazine articles shows how to do a stock mopar distributor...
Click to expand...


Ok, I have the distributor disassembled. I have the exact same number on the advance plate as the one in the article that Crackedback posted. I will be welding those slots as described.

Now as for the spring kit I just happened to have one of them. It says that if I use both of the springs in the kit full advance will be at 1200rpm.

Do I want to use 1 or both springs? How should I set that up?
 
The vacuum gauge needs to be hooked to manifold vacuum, not ported. It should be pulling close to 13" at idle when correct, not 1".

F the timing tape. Roll the timing mark to 10 btdc on your timing cover, make a mark at 5 ATDC, roll that new mark to 10 BTDC and make a mark at 5 atdc. run a scribe over each mark. You should now have a balancer marked so you can time the car anywhere to 40 BTDC. Marks will be 0, 15 and 30 BTDC.

It will look like this.
HillbillyTimingtape002.jpg


If you are looking over the drivers fender the new marks should be below your TDC mark on balancer.
 
crackedback said:
The vacuum gauge needs to be hooked to manifold vacuum, not ported. It should be pulling close to 13" at idle when correct, not 1".

F the timing tape. Roll the timing mark to 10 btdc on your timing cover, make a mark at 5 ATDC, roll that new mark to 10 BTDC and make a mark at 5 atdc. run a scribe over each mark. You should now have a balancer marked so you can time the car anywhere to 40 BTDC. Marks will be 0, 15 and 30 BTDC.

It will look like this.
HillbillyTimingtape002.jpg


If you are looking over the drivers fender the new marks should be below your TDC mark on balancer.
Click to expand...

I thought that the vacuum might have to be hooked up to manifold... The advance still gets hooked to ported correct?

Thanks for the idea to scribe the lines! Makes it much more simple and easier to read Im sure.

Just to be sure Im using a 318 timing cover with the timing marks cast into the cover and it reads. 10*BTDC, 0, 10*ATDC. With the before being towards the top of the engine or just under the water pump. That cover will still work correct?
 
when I check my timing I pull the vac advance hose that goes to the dizzy off the carb port. I cap the port on the carb and stick a screw driver in the line going to the dizzy. then set the timing base.

you want to make sure that when you hook your advance hose to the carb that you hook it to the timed vac port (only pulls vac above certain rpm) ....not the manifold vac port (pulls vac immediately at idle even which can cause the dizzy to advance at idle and advance to quickly/to much to soon when giving it gas).
 
xMOPARx said:
when I check my timing I pull the vac advance hose that goes to the dizzy off the carb port. I cap the port on the carb and stick a screw driver in the line going to the dizzy. then set the timing base.

you want to make sure that when you hook your advance hose to the carb that you hook it to the timed vac port (only pulls vac above certain rpm) ....not the manifold vac port (pulls vac immediately at idle even which can cause the dizzy to advance at idle and advance to quickly/to much to soon when giving it gas).
Click to expand...


Thanks, at least I had that hooked up correctly!
 
Ok, Distributor will welded up tomorrow and probably be ready to put back in tomorrow night. Im assuming I dont want to weld those holes shut anymore than what was in that article??

I also want to make sure that of what springs to install. If I install both of the light springs, full advance will be at 1200rpm. If I install one spring and keep the medium spring full advance will be at 2400rpm. Where do I want it at?
 
straightlinespeed said:
I thought that the vacuum might have to be hooked up to manifold... The advance still gets hooked to ported correct?

Thanks for the idea to scribe the lines! Makes it much more simple and easier to read Im sure.

Just to be sure Im using a 318 timing cover with the timing marks cast into the cover and it reads. 10*BTDC, 0, 10*ATDC. With the before being towards the top of the engine or just under the water pump. That cover will still work correct?
Click to expand...

The famed "Redneck Timing Tape"?
 
straightlinespeed said:
Ok, Distributor will welded up tomorrow and probably be ready to put back in tomorrow night. Im assuming I dont want to weld those holes shut anymore than what was in that article??

I also want to make sure that of what springs to install. If I install both of the light springs, full advance will be at 1200rpm. If I install one spring and keep the medium spring full advance will be at 2400rpm. Where do I want it at?
Click to expand...

Use one light spring and one original spring. Some distributors had a spring in them that was loose until the advance weights moved so far. Don't use that one, use the other spring that's snug at idle.
 
My car is timed at 10 With Vac disconnected at 800 rpm and then hook up vacuum advance which puts it up near 20 and turn rpm back down to 800. Is 38 at 2700 rpm. Anything other than this it is not happy. Will have to start from scratch once the SN93 gets installed
 
fishy68 said:
The article says they welded up the slots to .480" long and that gave them 20 degrees of advance. That would be real close to right for you too. .470" would probably perfect so somewhere in that range will work good for you.
Click to expand...

I don't know what article you read but that is NOT what I read. The 480 they mentioned was the BEFORE and as it happens the mechanism was stamped 15* distributor (30 at the crank)

http://www.moparmusclemagazine.com/...opar_electronic_ignition_system/photo_13.html

A chart a few of us have found floating around: It is important to understand that this is DISTRBUTOR degrees which is 1/2 what you see at the CRANK

Modifying advance slots
degrees / slot size
6.............. .340
7................355
8................375
9................390
10...............405
11.5 ...........420
12...............435
13...............445
14...............460
15...............475
16...............490
17...............505
18...............520
 

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67Dart273 said:
I don't know what article you read but that is NOT what I read. The 480 they mentioned was the BEFORE and as it happens the mechanism was stamped 15* distributor (30 at the crank)

http://www.moparmusclemagazine.com/...opar_electronic_ignition_system/photo_13.html

A chart a few of us have found floating around: It is important to understand that this is DISTRBUTOR degrees which is 1/2 what you see at the CRANK

Modifying advance slots
degrees / slot size
6.............. .340
7................355
8................375
9................390
10...............405
11.5 ...........420
12...............435
13...............445
14...............460
15...............475
16...............490
17...............505
18...............520
Click to expand...

I read the same article but my eyesight wasn't doing good last night (diabetes acting up) and I got in a hurry reading it so I mis-read it. They said it measured .480 before modifying it

We wanted to run about 15 degrees of initial advance (at idle), and have the
engine timed for 35 degrees total (at full mechanical advance). That means the
distributor needs to provide 20 degrees of mechanical advance instead of the 30
in the factory plate. To shorten the mechanical advance, the slots need to be
shortened. The slots in our plate measured .480 inch long. We zapped the ends of
the slots with a MIG welder to get some of the advance out of our plate
Click to expand...

Read more: http://www.moparmusclemagazine.com/...ic_ignition_system/viewall.html#ixzz2bo3Z3Wwh

My apologies to the OP for my mistake.

BTW: I realize the stamped # on the mechanism means degrees at the distributor but didn't think it was important to get so technical so I didn't mention it. After all the outcome is the same as long as you make the slots the right length, is it not?
 
OK slot is all set and distributor back into the car. I started at 8* btdc. Set idle to 800, and adjusted the carb. I was originally pulling around 10 on the vacuum at 1.5 turns out. Started unscrewing the screws equally out and got up to 13-14. Readjusted the idle and then reved it up to about 3k. I was only at about 30*.

I retimed to about 13* ran thru all those steps and was closer to 38*. Hooked advance up, Got in the car and put it into gear and it dropped about 300rpm. Shut car off and it chugged and backfired thru the carb. So I re did everything at 10* initial. Reset everything and was about 34* total. But now I'm dropping about 4-500 rpm in gear and its not liking it.

Couple questions. I'm not totally sure my idle screws are working properly. I have the left screw out 3.5 turns and the right 3.25 turns. Only able to pull 13-14 vac. Is it normal to have them turned out that far? If I'm backfiring thru the carb do I want to advance it or retard it? If I retard it I'm getting further away from the 34-38* range? Is that Ok, is there a point that is to low?
 
That's a lot of turns in my opinion, even with a Eddy/Carter style carb. I think you seem to be getting a handle on the timing, so i have to wonder how lean that carb is, for whatever reason. Let's see what some others think?
 
OldmanRick said:
That's a lot of turns in my opinion, even with a Eddy/Carter style carb. I think you seem to be getting a handle on the timing, so i have to wonder how lean that carb is, for whatever reason. Let's see what some others think?
Click to expand...

Totally agree with you Rick. I've had a lot of carters and Eddy's and usually never have to turn the idle mixture screws out more than 2-1/4~2-1/2 turns.

Straightlinespeed reset the timing to 13 degrees initial and verify it's 38 total. Then try re-adjusting the carb and see what happens. I assume when you adjusted it earlier you had the engine warmed up good? I always adjust the carb in gear as that seems to produce the smoothest idle, but in your case if it won't run in gear that may not be easy.

Have you tried pulling off each plug wire at a time to make sure all 8 are firing? Maybe something else to verify. A misfiring plug or wire could be the reason it's backfiring. The timing you have it set at now should never make an engine backfire. You have to be pretty far off to get them to backfire.
 
Make sure the engine is FULLY warm / up to temp when you adjust idle

You MAY have a vacuum leak causing a lean condition. I agree--- sounds way lean.

Do NOT retard timing to "fix" chugging--the opposite. Set timing, adjust idle screws best you can for highest vacuum/ best idle, then diddle idle speed and adjust timing for now I'd LEAVE it at the 13/ 38 unless the engine seems to like more at idle. More idle speed/ more vacuum is an indicator. Keep backing the idle speed down as you improve idle.

Try pulling the idle screws clear out when running and stick your finger over the hole. This tends to pull out any dirt. If no effect, get some aerosol carb cleaner with a snorkel and blow some cleaner through the idle screw holes. Watch your eyes, it should come up out of the air bleeds int the throats.

The question is "have you improved it?"
 
I'll throw out one crazy notion before I hit the sack...........Are you hooked up to a power brake booster?
 
You mean B&M makes good converters?
 
RustyRatRod said:
You mean B&M makes good converters?
Click to expand...

Not in my opinion Rob. Hit and miss at best.....mostly miss. :D

The one's I messed with were inefficient and didn't do as advertised. With that said, I never had one that kept the car from halfway running. But there's always a first time...lol.
 
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