M37 Points & Condenser Question??

[UZIS9MM]

Alright, instead of highjacking another thread I figured that starting a new one was easier and would probably get more response.

Here it goes. All the debate on the other thread about the pro's & con's of stock points & condenser vs. the solid state replacement got me a little worried about my M37.

I've had my truck for thirteen years now with the same condenser and points and have put about a 1000 miles a year on it during that time and it has always run like a nut. I have periodically checked the points and cleaned them but I have never had to adjust them as they have always checked out at .019 - .020 with a feeler gage (the .019 goes in freely and the .020 goes in with very slight resistance). Is getting this kind of life out of the points normal or am I just extremely lucky that I haven't had any problems to date??

By what I was reading in the other thread it seems that the points on these old trucks need almost constant attention in order for the engine to run correctly, is this true or am I just misinterpreting what I'm reading?

Points have been my maintenance weak spot with this truck as I know how to adjust and maintain them but I'm not getting a lot of practice because everytime I crack open the distributer everything is fine. From what I'm reading it shouldn't be that way and I should be adjusting something everytime I open the distributer.

Please advise.

Kevin

[Nickathome]

I installed new points condensor and coil when I first bought my truck, and have never checked them since. They have worked fine for me. No need to upgrade IMO.

[UZIS9MM]

I'm not planning on upgrading. The old "don't fix it if it ain't broken" proverb applies when it comes to these things.

The question should have been if the system is properly maintained how often do you really need to check/adjust the points?

I've gone 13,000 miles without a hiccup from the distributer and I'm just wondering if it's common for the points to go that long without needing adjustment.

Kevin

[MSeriesRebuild]

How long it will go before an issue develops would be different in every truck for any number of reasons. If I were you, I would go ahead and change them out at first opportunity, it is a real possibility that after that long you may be pressing your luck. Sometimes you will get a warning from erratic performance, sometimes it is without warning and you are stranded.

Pertaining to your adjustment question, if you're checking the gap and it is a snug .020", adjustment is not needed. If the contacts are dirty and require cleaning, then readjustment will be necessary after the cleaning. Lots of factors affect corrosion details, checking periodically is the only way to know for sure. A good preventive maintenance effort here is a necessity, kept up properly will greatly lessen the chances of problems in the area. If you are lax on doing this periodically for whatever reason, you are indeed better off going solid-state.

[cuz]

1000 miles was never a milestone for changing points and shouldn't be used for one now. Calendar Age will impact from a corrosion standpoint but mileage should go to at least 4,000 miles or better without any requirement for adjustment. Should get at least 12,000 miles before wear necessitates replacement. All of these figures are based on real world experience with contact point ignition and the use of quality points and condensers.

[Lifer]

Agreed! I put over 40,000 miles on a '66 Chevy Caprice with a 283/powerglide combo in it after my father-in-law gave it to me. I don't know when (or if) he changed the points, plugs, and condenser, but I know he was not really concientious about maintenance on anything. The points that were in it when I got it were still in it when I sent it to the junk yard after my son wrecked it. At the time, it was still running strong and smooth as silk. While I had it, I adjusted the points every 5,000 miles and polished 'em up a little bit with the emery cloth while I was in there, but I haver had to file them or replace them. Incidentally, they were Blue Streak points if that makes any difference (which it doesn't, in my book).

What Cuz and I are sayin' here is that points work just fine for a long time if properly cared for. It's the "if properly cared for" part that's important!

[Sal]

I'm thinking off the top of my head here but would the 24 volts have anything to do with premature wear on the points?

[cuz]

No. They do not see 24 volts in use. Premature wear is caused by the not so smart things we do to them. Simple things like getting our finger skin oil on them during an install. Filing them with silica based materials. Leaving the ignition switch on. Failure to lube rubbing blocks. Man is his worse enemy here too.

[Josh]

I think the pivotal point (no pun intented) being overlooked here is the type of engine they are going on. As specific power per unit of displacement of engines is driven up, ignition systems need to evolve as well. There is a reason that modern naturally asiprated engines can belt out over 100 HP/L on a regular basis. On the stock 230, the compression ratio is only 6.5:1. At 6.5:1, your cylinder pressures are somewhere around 95-100 PSI. The flathead combustion chamber also promotes ignition with its characteristic hot spots due to the long shape. As a result, it only takes around 12kV to light a plug in the 230. 12kV on a breakered type ignition is very forgiving. In my twincharged monster, I eventually plan on getting to 25-30 PSI of pressure with an 8.5:1 CR. My cylinder pressures will be around 255 PSI, and will require at least 21kV to fire the plug (assuming a .030" gap)... 21kV will be much less forgiving of points that are not maintained in top condition.

When you get to modern ignition systems, like my coil per cylinder GM LS1 packs, 40K+ volts are not uncommon, and would be hell on a points type system due to the increased oxidization rates on the points from teh high voltage. The other issue would be maintaing the spark through the points.. at the high a voltage, humidity would pose an issue with arcing to ground and other phenomenon.

So, bottom line: low CR with low voltage ignition: no problem.

Try firing 45kV through points: Problem.

[cuz]

I am sure no one here ever intended this discussion to include man made fire breathing dragons!

It's about 230 cu in 6.5 CR engines with a few parallels to same historical period small V8s.

[gwalker]

The brand of points does make a difference, as it happens nowdays the
StandardBrand Blue Streak points are the very best Al4556XP(Standard also has a cheap line that come in a red box), most other brands now sell the same low quality chinese made ones. Points, once the standard were a thing of the past by the late 70's, and today most of the knowledge for selecting, installing and maintaning them is lost as well. Points wear 2 ways mechanically by loss of the rubbing block material, and electrically by loss or transfer of the metal at the contact area. The wear of the rubbing block causes the gap to change, electrical wear can be different an tells of the condition of other parts in the circuit, typically if you look very close the metal will wear off one side and build up in a uneven manner on the other side, this can also result in a improper gap and requires filing to make it smooth agian. For the detailed oriented they used to ck the tension of the points and the exact alignment of them when closed, as well these could cause problems. Test machines used to be made that allowed a dist to be installed and operated right in front of you allowing all these adj. and further tests to be more easily made. Back to the Blue Streak points they are the last good quitlty ones left on the market, not that the others dont work they just dont last so long, the difference is they have an oiling wick which keeps the dist shaft lubed resulting in slower rubbing block wear and they are vented. Vented points have a hole in the fixed side contact which keep the contacts cooler during operation resulting in slower wear here. Of course in the old days it wasnt as big a deal, points cost at most a couple dollars a set and any parts store had them, today however they are at least several dollars and are increasingly hard to find in stock at a parts store. (I have to find the Blue Streak ones online as the local store wont get them for me) The last consideration is that when points are off so is timing an to a lesser extent fuel mileage, Now that you know more than you care to about points I personally opt for electronic ign. its always right on, so you not always ck'ing and adj'ing points which in the 37 arent real easy to get to anyway. I have used the brand of electronic ign. kits mentioned on this site since early 90's and they have been exceedingly reliable for me.

[MSeriesRebuild]

The brand of points does make a difference, as it happens nowdays the
StandardBrand Blue Streak points are the very best Al4556XP(Standard also has a cheap line that come in a red box), most other brands now sell the same low quality chinese made ones. Points, once the standard were a thing of the past by the late 70's, and today most of the knowledge for selecting, installing and maintaning them is lost as well. Points wear 2 ways mechanically by loss of the rubbing block material, and electrically by loss or transfer of the metal at the contact area. The wear of the rubbing block causes the gap to change, electrical wear can be different an tells of the condition of other parts in the circuit, typically if you look very close the metal will wear off one side and build up in a uneven manner on the other side, this can also result in a improper gap and requires filing to make it smooth agian. For the detailed oriented they used to ck the tension of the points and the exact alignment of them when closed, as well these could cause problems. Test machines used to be made that allowed a dist to be installed and operated right in front of you allowing all these adj. and further tests to be more easily made. Back to the Blue Streak points they are the last good quitlty ones left on the market, not that the others dont work they just dont last so long, the difference is they have an oiling wick which keeps the dist shaft lubed resulting in slower rubbing block wear and they are vented. Vented points have a hole in the fixed side contact which keep the contacts cooler during operation resulting in slower wear here. Of course in the old days it wasnt as big a deal, points cost at most a couple dollars a set and any parts store had them, today however they are at least several dollars and are increasingly hard to find in stock at a parts store. (I have to find the Blue Streak ones online as the local store wont get them for me) The last consideration is that when points are off so is timing an to a lesser extent fuel mileage, Now that you know more than you care to about points I personally opt for electronic ign. its always right on, so you not always ck'ing and adj'ing points which in the 37 arent real easy to get to anyway. I have used the brand of electronic ign. kits mentioned on this site since early 90's and they have been exceedingly reliable for me.

The points gwalker has brought out in his post are spot on. This is virtually the same things I was thinking in my reponses to some previous post that turned into pros/cons of pointless ignition. I just haven't had the time lately with the work load, (both on and off the job) to sit down and really say all that came to mind concerning this, plus when you have someone with time on their hands who is dead bent on posting a contradiction to everything you say, well after while I just say the heck with it, no longer worth my time, as this leads to other issues that help nobody who has a serious question about the subject. I just don't care to take it into that realm. I have learned a few lessons along those lines.

Anyway, the bottom line to the subject that is front and center here is this. Anytime that a reliable update product exist that substitutes mechanical moving parts, in 99% of cases it will be a PLUS. Mechanical parts have wear issues, corrosion issues, and in this case spring pressure issues that promotes other wear issues and so on. These issues cause a consistant need for routine inspection, cleaning, adjustment, etc, etc. Having performed this routine maintenance on customers trucks for many years, I can surely attest to the fact that the introduction of a product that largely eliminates the need for at least some of the routine stuff is always a welcome product in the marketplace. The pointless ignition modules were almost a God send to fire service trucks. They need to be unquestionably ready to roll when the need is there, electronic ignition modules played a huge roll in the reliability of these trucks. Fire service vehicles are maintained on strict scheduled maintenance programs. I've known corrosion on point contacts to be the issue in failures more than once. Contacts will get corroded especially in high humidity areas, even when points are replaced frequently as a preventive maintenance measure. This is a point that any reasonably intelligent person can relate too on the subject of a points/condensor type system being just as reliable. Common sense tells me that just is not true.

So thanks gwalker for opening a new door in this thread that for various reasons I didn't take the time to do.

I'll point out 1 more issue that falls in this category also. Nobody has mentioned about the utmost importance of keeping the top shaft bushing oil wick soaked with oil constantly. The top bushing gets no oiling from the engine like the bottom bushing does. Always remember to go about removing the elbow plug and filling it with oil as the consequences of not doing it will bring problems rather quickly. We build a lot of distributors here for customers. I'd say in probably 95% of the ones we build, no attention has been paid to the top bushing lack of oil issue. This one factor accounts for THE source of specific problems people tell us they are experiencing in more cases than any other factors. Lack of lubrication in the top bushing causes bushing/shaft wear, as this wear grows worse and the shaft starts to bounce around and no longer runs true in its bore, maintaining points adjustment is impossible. This will be especially noticable at higher RPM's as the points gap is literally all over the place. The cam oil wick that is under the rotor is also another lubrication factor that was not mentioned. The cam that opens the points as the shaft rotates must move freely on the shaft in order to properly advance the timing as centrifugal force moves the weights. I've seen many a cam and shaft that were either seized or worn out as a result of no lubrication. This certainly brings performance issues to light. Most folks I mention this to are not even aware these lube points exist, much less the proper maintenance and importance of keeping the wicks oiled. Proper lubrication of these areas is absolutely VITAL to a dependable well functioning distributor. Very seldom do they even get mentioned when distributor discussions come up. Since these are 2 KEY issues necessary to keeping the distributor top notch, I wonder why they are so often overlooked?

[cuz]

I wish to thank the moderator who was thoughtful enough to point out to the previous poster how wrong his original post above was. Saves me the trouble of an additional long winded off topic disortation here in the middle of Kevin's ignition points specific thread.

Sorry Kevin. I just do not understand why folks have to be so uncuth and hi-jack someone else's thread.

[UZIS9MM]

Cuz, no problems here. I enjoy a little debate sometimes, it keeps things interesting.

Charles, thanks for addressing the lubrication points in/on the distributer, especially that top shaft bushing. You are VERY correct about those being to often ignored (I'm guilty as well). Thankfully someone modified my distributer a long time ago with an elbow and filled it with a thick oil/grease type mixture. I scooped out some of the mixture and put some 30 weight motor oil in the elbow just in case the stuff that's in there isn't getting to where it needs to go. After opening the distributer again last night I was able to check the runout on the distributer cam shaft and everything checked out so I don't think there is any damage or noticable wear to the top bushing.

Again I don't have any plans on changing my current distributer system out for something more modern. I enjoy the challenge of keeping the old girl on the road in her stock condition. I understand that the pointless system requires little to no maintenance but it's the maintenance that keeps things interesting and keeps me coming back for more. Call me a glutton for punishment but I enjoy the almost constant tinkering, adjusting, and lubricating of various components to keep my truck purring like a kitten.

Thanks for all the replies so far, I look forward to more so keep'em coming.

Kevin