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jg61hawk
06-21-2016, 06:45 PM
Driving on Sunday to RI for the meet and just so happens yesterday an old guy gives me an old (But new in the box) dwell / RPM meter. I read the instructions and check my V-8 Hawk which is running great and find the dwell is 22 and the book says like 27-32. Should I attempt to fix that which is not broke? I don't know what dwell is but I know it has to do with the point gap so I can play with that. The trip is 225 miles each way. I suspect I have to open the points...just a guess but they must have worn? The car is running very well. Thanks. Jim

DEEPNHOCK
06-21-2016, 07:00 PM
Does your dwell meter have a 6cyl and 8 cyl setting?

As gap increases, dwell decreases, so your point gap would need to be closed up to increase your dwell.

If your engine is running great, I would suggest checking it in three weeks.

BobPalma
06-21-2016, 07:01 PM
:) That is too little dwell, Jim, and it should be adjusted to spec before you leave. However, make sure you have the meter scale set to 8 cylinders and not 6 (or something else) before making the adjustment.

Simply stated, Dwell is the number of degrees the distributor shaft rotates (out of a 360-degree circle) while the points are closed. As soon as the distributor cam comes around and opens the points, breaking the circuit, the dwell can be determined. Of course, all this happens rapidly while the engine is running.

Reset your points carefully with a feeler gauge. Then check the dwell and it should be within spec. :cool: BP

karterfred88
06-21-2016, 07:08 PM
Me, I'd reset the points, or install a new set and set to the highest recommended dwell to account for wear in of the point block. If the rub block wears some more, it won't be "running very well", and might catch up with you just when you don't want it to. Hold on to that old dwell tach they are getting harder to find and are indispensable setting point type distributors and setting timing without trying to see the car's tach-if you have one.

DEEPNHOCK
06-21-2016, 07:13 PM
If he changes the dwell, Jim will need to re-set the timing.
This is a decision point on all Stude's on all road trips.
Of course it should be tuned to the peak of efficiency before leaving.
Is Jim in a position to do a thorough tune up?
Having just been handed the most basic of tune up tools, I would not suggest learning tune-up 101 with a road trip facing you.
IMOHO, if the point surface looks good, and the engine is running great, I'd leave it alone until after the meet.
Either all in or all out.
Get someone to help with the tune up, or wait until you get home.
Just an opinion... I am making an assumption about Jim's tune up ability.
So if I am out of line...slap me down,

jg61hawk
06-21-2016, 07:26 PM
Thanks for the suggestions. To hear from Bob Palma is an honor! DeepnHOCK you did not nearly insult me. I'm pretty good with this old gal and have always just set the points and did the tune up, for over forty years. Never had a dwell meter. Now I'm dwelling on this (pun). I'll take the advice and play with the points. The following (blue) was taken from some internet site, so Ill error on the side of too little, meaning I'll look at the Shop Manual and aim for the smaller number, which I believe was 27. Either way I'll be in RI. Me and this old Hawk go way back, I'll kick it down the road or we'll fight along 95 in CT. Thanks again! Too little dwell and the coil will be undercharged resulting in a weaker spark. Too much dwell and the coil will overheat. An overheating coil will breakdown easier, won’t store as much energy and will result in a weaker spark

karterfred88
06-21-2016, 07:44 PM
Well you know it's true if it's on the internet! :rolleyes:

thunderations
06-21-2016, 08:10 PM
If timing was set with the dwell correct, re-setting the dwell back to correct will bring the timing back to correct also.

Dan Timberlake
06-21-2016, 08:14 PM
Aren't R-1s supposed to have dual point distributors?

Chipmaker
06-21-2016, 08:35 PM
I would check the meter against a known good one befor useing it.I have seen some go bad(read incorrect)over time.

doofus
06-21-2016, 08:35 PM
I think you are mistaking R.I. for R1 , state vs engine. as Abe Lincoln once said " you can't believe everything you read on the internet". Doofus

jclary
06-21-2016, 08:57 PM
Thanks for the suggestions. To hear from Bob Palma is an honor! DeepnHOCK you did not nearly insult me. I'm pretty good with this old gal and have always just set the points and did the tune up, for over forty years. Never had a dwell meter. Now I'm dwelling on this (pun). I'll take the advice and play with the points. The following (blue) was taken from some internet site, so Ill error on the side of too little, meaning I'll look at the Shop Manual and aim for the smaller number, which I believe was 27. Either way I'll be in RI. Me and this old Hawk go way back, I'll kick it down the road or we'll fight along 95 in CT. Thanks again! Too little dwell and the coil will be undercharged resulting in a weaker spark. Too much dwell and the coil will overheat. An overheating coil will breakdown easier, won’t store as much energy and will result in a weaker spark

A few weeks ago, I created a perfect example of the problem you describe in the above quote. On one of my six cylinder Studebakers, I installed a new set of points without truly "setting" the gap.:oops: What I did, was pop them in, and left the eccentric adjustment screw untouched, and merely "eyeballed" the point gap, and called it "OK.":yeahright: Not that I can't set the points, but, this time, I was impatient, and in a hurry to move on to other things. I simply popped the new points in place, slapped the distributor cap back on, and was impressed when the engine fired right up.:p:)

The slower than usual cranking over of the engine should have been a clue. But, I didn't pay enough attention.:o I backed the car out of the barn, and parked it in the yard, to hose the spring pollen off. I left the car setting in the yard while I took care of other chores. Later in the day, I noticed thunderheads coming over the mountains. So, I scrambled to fire up the car and get it back under shelter. However, not only did the engine drag and turn over slowly, it dragged the battery down to the point that I had to grab my wheeled heavy duty battery charger.:QQ: Using the "boost" starter, the engine fired up and I was able to get it in the dry before the rain started.:)

Realizing, that I had used an "eyeball" set on those points, the next day, I took my trusty feeler gauge set, and checked my "eyeball" accuracy. The manual calls for .020 for this six cylinder. My "eyeball" set was over .040!:oops: Which proves that these engines are more forgiving than you would think. But, at the same time, the settings are there for a reason, and, although the engines might run with the settings off...they run much better with the settings "CORRECT!":!: With the points set correctly, they are not opening too soon, trying to fire the piston on the upstroke. That was the reason for the slow reluctant cranking speed. With correct points gap, the engine cranking speed is quick and crisp, with the engine firing up almost instantly.:)

jg61hawk
06-21-2016, 10:02 PM
Getting older then when I bought the car 40 years ago, but not too lazy to work at night. Dwell is now 29. Checked with the old one the guy gave me, and me being a little nuts, I bought one at Auto Zone (who thought they would have one)>both 29 and no real variation when gas is moved so I think that shows the distributor bearings are OK.

HAVING SAID THAT, I'LL RISK HERESY HERE. Maybe that Ford 289 with the distributor in the front ain't so bad after all! I forgot how much fun crawling into the back of the motor was, especially hoping my ass don't hit the prop rod and close the hood on me.

See you in RI. (God willing)!

BILT4ME
06-22-2016, 08:02 AM
Dwell is actually more important than the point gap itself. The gap is a "suggestion" to get it close for the dwell. The ideal location is the center of the range. Studebaker gives a very wide range in the book compared to some other makes.

I have mine set at 29 as well and it starts on the first turn every time. It has excellent power, and runs smooth. Yes, it's a pain to adjust it multiple times to change the dwell by 1 degree.

Gotta get your idle set correctly first though. I have a really hard time with my car idling at 500 RPM in D. Just feels like it's going to die. It feels happier idling at 800.

JWL4541
06-22-2016, 09:49 AM
Good advice from the above posts. In addition, some dwell meters also have a scale for checking the condition of the points. Basically it is a measurement of the current across the points. Too much current and the points have too high a resistance and need replacing. A quick way to determine condition. This feature, if available, should be covered in the meter's instruction manual. Thanks.

(o{}o)

IMJ
06-22-2016, 12:10 PM
I’m a little bit confused, ok a little bit more than normal. If dwell decreases as gap increases, shouldn't the point gap be set at the high end of the range to compensate for a little wear on the point block of a new set? Doesn’t the point gap decrease as the block wears on a new set? Shouldn’t the dwell be at the lower end of the range on a fresh set of points?

regards,
Jay

jclary
06-22-2016, 01:04 PM
I’m a little bit confused, ok a little bit more than normal. If dwell decreases as gap increases, shouldn't the point gap be set at the high end of the range to compensate for a little wear on the point block of a new set? Doesn’t the point gap decrease as the block wears on a new set? Shouldn’t the dwell be at the lower end of the range on a fresh set of points?

regards,
Jay

My humble attempt to describe/explain "dwell"...think of bucket (coil) and a garden hose (your 6 or twelve volt power supply). You are needing to dump a large volume of water (electrical current) quickly. To accomplish this, you take your garden hose (compare that to the electrical current... the primary electrical circuit flowing through your points) and fill the bucket. The time it takes to fill that bucket, is your "dwell" time. Once you have the required water in the bucket (your coil)...you put down the garden hose (open the points), grab the bucket, and quickly dump the entire volume of its contents!(that fires your spark plug!) If you don't fill the bucket (your coil), the content is less, and probably dumped too soon.

I like to think of the process of setting the point gap, as a "gross" ballpark setting. Precise setting is possible with a feeler gauge, but a dwell meter is the best way I know of "confirming" the setting. You can't really measure it as "time," but in terms of angle. Since the true time varies with RPM...mechanical angle stays the same, regardless of speed. Thus...DWELL ANGLE.

"Time," is compensated by (I think) the relationship of a coordinated combination of vacuum advance, centrifugal weights, and carburetor accelerator pump, to adjust in anticipation of demand variations.

All of the above, may not be completely accurate. Feel free to correct, expand, and expound at will.;)

DEEPNHOCK
06-22-2016, 03:03 PM
This has been discussed numerous times on the forum over the years.
You are correct. The things that 'wear' are (a) the rubbing block, and (b) the point surface itself.
The point wear will increase the gap (but it is never an 'even' wear).
The rubbing block wear will decrease the gap (thus increasing the dwell)
My experience has been that the rubbing block will wear faster than the points will erode.
So, I always set my dwell on the low range of the suggested dwell range.
That way the dwell will work it's way up through the suggested range and the tune up will last longer.



I’m a little bit confused, ok a little bit more than normal. If dwell decreases as gap increases, shouldn't the point gap be set at the high end of the range to compensate for a little wear on the point block of a new set? Doesn’t the point gap decrease as the block wears on a new set? Shouldn’t the dwell be at the lower end of the range on a fresh set of points?

regards,
Jay

altair
06-22-2016, 08:21 PM
I am a true back yard mechanic. A previous vehicle I once owned, a 6 cylinder had an assigned point gap of .018 -.020. I would always set the gap to .020 first then set the timing with a light bulb (static) turn the fan until the light comes on and check the timing mark. I would repeat the process until the timing mark and the light were in line. When the timing was locked up it never had to be touched again. The telltale that the points (dwell) was out of wack would be incipient slight pinging. I would either reset the points back to .020 or replace them. It was usually easier to pull the distributor when replacing the points for this work and therefore the timing would require to be reset. If just resetting the points, the timing did not have to be touched.

DEEPNHOCK
06-23-2016, 05:33 AM
That's how they (used to) set the timing on all the top fuel dragsters and funny cars (even though they had magneto's).
Very sound method.


I am a true back yard mechanic. A previous vehicle I once owned, a 6 cylinder had an assigned point gap of .018 -.020. I would always set the gap to .020 first then set the timing with a light bulb (static) turn the fan until the light comes on and check the timing mark. I would repeat the process until the timing mark and the light were in line. When the timing was locked up it never had to be touched again. The telltale that the points (dwell) was out of wack would be incipient slight pinging. I would either reset the points back to .020 or replace them. It was usually easier to pull the distributor when replacing the points for this work and therefore the timing would require to be reset. If just resetting the points, the timing did not have to be touched.

TWChamp
06-23-2016, 06:03 AM
I haven't seen any mention of distributor cam lubrication. Be sure to lube the rubbing block to prevent wear, or at least slow it down as much as possible. I like to give the cam a light coating so it doesn't rust from condensation. Also make sure the grease or oil cup is filled with lubrication every so often.

While on a day tour one guy's distributor seized and broke the tang of the shaft because he wasn't aware of the oil cup on the distributor. Three of use stayed behind to get him back on the road, but it was too late for the tour, so we just drove home.

IMJ
06-23-2016, 07:23 AM
[QUOTE]install a new set and set to the highest recommended dwell to account for wear in of the point block./QUOTE] ???

[QUOTE][/I’m a little bit confused, ok a little bit more than normal. If dwell decreases as gap increases, shouldn't the point gap be set at the high end of the range to compensate for a little wear on the point block of a new set?]

[QUOTE]So, I always set my dwell on the low range of the suggested dwell range.
That way the dwell will work it's way up through the suggested range and the tune up will last longer.
/QUOTE]

DEEPNHOCK
06-23-2016, 07:37 AM
Yes, you should use a small amount of cam lube to slow the rubbing block wear.
If your block wears (faster then the points themselves) then the gap will be decreasing as the block wears.
If the gap is decreasing, then the dwell will be increasing.
So... If you set the dwell the the low range number, and the dwell will be increasing due to the gap decreasing then your tune up should last longer.



[QUOTE]install a new set and set to the highest recommended dwell to account for wear in of the point block./QUOTE]

[QUOTE][/I’m a little bit confused, ok a little bit more than normal. If dwell decreases as gap increases, shouldn't the point gap be set at the high end of the range to compensate for a little wear on the point block of a new set?]

[QUOTE]So, I always set my dwell on the low range of the suggested dwell range.
That way the dwell will work it's way up through the suggested range and the tune up will last longer.
/QUOTE]

JoeHall
06-24-2016, 09:57 AM
Just install Pertronix, and forget all the hassle of points. You will still need to put a few drops of oil on the felt beneath the rotor button, and in the outside oiler though, now & then.

6hk71400
06-25-2016, 01:43 PM
Correct me if I am wrong, but I always thought that timing effects dwell, but dwell does not affect timing. After reading this tread, I don't think that has been clearly stated. I always set the timing first, then set the dwell, but after a couple of strokes and a seizure, I may be wrong in my memory. The medications I take and rehab has brought me back to 90 percent but sometimes I don't trust my memory.

Bob Miles
Tucson AZ

jclary
06-25-2016, 04:42 PM
Just install Pertronix, and forget all the hassle of points. You will still need to put a few drops of oil on the felt beneath the rotor button, and in the outside oiler though, now & then.

Well...that depends...on the Pertronix working correctly, installed correctly, and the owner understanding it.:) We've seen several threads of problematic component failure and conversions here.:( Personally, I have zero experience with a vintage distributor converted to electronic. The SDC member, who comes to my mind, as the "go-to guru" for electronic distributor conversion, is Dave Thibeault. Not only does he modify, service, and sell them, but a "true believer," in his product.:!: So much so, that while talking personally with him at the South Bend Swap meet, he explained the way they operate in clear, understandable terms.:yeahright: In fact, it made so much sense, I was ready to convert all my Studebakers, my 8N Tractor, and a couple of lawn mowers!:D:cheers: It was when he gave me a price:ohmy:...that this ol' hillbilly's wide eyed excitement immediately, returned to my natural "cheapo" reality.:rolleyes: I decided even the ECM controlled ignition system in my Dodge Ram...all those great features of an electronic system...still couldn't get me the more than six hundred miles home, without enough gas money.:QQ::lol:


Correct me if I am wrong, but I always thought that timing effects dwell, but dwell does not affect timing. After reading this tread, I don't think that has been clearly stated. I always set the timing first, then set the dwell, but after a couple of strokes and a seizure, I may be wrong in my memory. The medications I take and rehab has brought me back to 90 percent but sometimes I don't trust my memory.


Bob Miles
Tucson AZ

Bob, sorry about the health issues. We never know when the next physical "ambush" will happen, but a risk we all face. Regarding timing...I think it is a subject we often conflate.(So,please, don't take this as a put-down condescending post. I'm as guilty, as anyone, of losing focus, and confusing the two)

In our engines, there are two cams involved in timing. While both are related, and one affects the other, there's "Valve" timing, and "ignition" timing. First, the valve timing, a purely mechanical function, has to be performed. Once the main engine cam by way of proper cam gear/crank gear, is properly set in place, it is further adjusted by "valve" adjustment, and those related components.

Once the "mechanical" components are set...comes "ignition timing." Here, we encounter the second cam, the distributor cam. As I posted earlier, this is where electrical meets mechanical. So, "Mechanical timing" & "Ignition timing." The distributor (ignition) cam, something that is usually so reliable, that it can lead to all sorts of trouble and confusion if ignored.:(

A good example, is my 1951 Land Cruiser. I acquired it in 1988. It had sat for years. In 1971, the car had less than 51,000 miles. In 1988, 56,000 miles. When I got it, there was a skip in the engine. New ignition points, rotor, condenser, spark plugs, distributor cap, and plug wires, and it still had the skip. Finally, off with the valve covers, and a mechanical valve adjustment.:p...and the skip remained.:QQ:



Like the previous owners, I parked the car, moved on to other things, and would occasionally, fire up the car, take a short drive, but totally disgusted with the mysterious skip. Then one day, while pilfering through a "bulk buy" I had made on a stash of Studebaker parts, I discovered a NOS distributor.:!: Almost as an afterthought, I installed it in my Land Cruiser. To my surprise, it solved the skip.:cheers: Apparently, the original distributor had a bad distributor cam lobe.:ohmy: I've often wondered, if that one overlooked problem, was what saved this car from being used up, worn out, and discarded.:confused: I suppose we'll never know.

6hk71400
06-25-2016, 10:32 PM
Thanks John. I am doing great really and not worried about what the next ambush may bring or if even I have another one. After surviving nightly mortar attacks plus the constant small arms fire when I was out of the base area while I was TDY in Saigon in 1973, I always try to take everything in stride.

Thanks for the refresher on timing. Having either a Studebaker six or eight in tune is a joy to hear and drive.

Bob Miles
Tucson AZ

jclary
06-25-2016, 11:07 PM
Thanks John. I am doing great really and not worried about what the next ambush may bring or if even I have another one. After surviving nightly mortar attacks plus the constant small arms fire when I was out of the base area while I was TDY in Saigon in 1973...
Bob Miles
Tucson AZ

Understand that Bob...I was there for the little dust-up known as "The Tet Offensive".:ohmy: We got it while "in base" area...the "mortars" lobbed at us, were actually 122mm rockets. A few weeks before I finished my tour...I was ordered to fill in the elaborate "fox hole" I had dug next to my barracks. I got so fed up with all the choking dust (and subsequent sore throat) stirred up when we had to scramble to our bunkers, that I spent several days, digging my personal hole in the ground. I scrounged up an old chair to sit in, and I even stored some spare C-ration kits, so I could have a snack while waiting for the "all-clear" signal. A few weeks before my time to leave, we had some of those monsoon gully washer rains that flooded my sanctuary.
I think they were afraid someone would inadvertently stumble in and drown.:oops: Filling that hole back in, while enduring the tropical heat, was much easier that digging it. Knowing that, by then, I was a "short timer" helped as well.:)

Dan Timberlake
06-26-2016, 08:36 AM
Correct me if I am wrong, but I always thought that timing effects dwell, but dwell does not affect timing. After reading this tread, I don't think that has been clearly stated. I always set the timing first, then set the dwell, but after a couple of strokes and a seizure, I may be wrong in my memory. The medications I take and rehab has brought me back to 90 percent but sometimes I don't trust my memory.

Bob Miles
Tucson AZ

=============

Hi Bob,

If I change the dwell very much with the distributor installed in the engine, the ignition timing will change too.
I think it's about 1 for 1, since the dwell angle is the total "time" the points are closed, so an extra degree of dwell adds 1/2 degree to each end of the points closed period.
BUT the spark happens on the end when the points open so is only affected by the 1/2 degree added there.
HOWEVER since the distributor turns at 1/2 engine rpm, 1 distributor degree = 2 crankshaft degrees, which is how ignition timing is referenced.

So, set the point gap, check the dwell, then finally check the ignition timing.

Oh, and then with the vac advance plugged on the carb,I rev the engine up looking for a smooth ignition timing increase/decrease as rpms change to be sure the centrifugal advance is actually working.
If it ain't, then I'm going to have to go back into the distributor to fix and clean, so the points dwell will have to be checked again.