12 volt condensor

[Little Jo]

Hi Guys

I have been experiencing some power problems when driving my 1942 MB Willys Jeep. It appears when I accelerate and the jeep is put under pressure she loses power, but as soon as I shift down and increase the revs she drives OK again until the next hill. I have checked everything from Carbie to coil, plugs and points. I then had a thought, when I changed from the 6 volt to a 12 volt system I changed everthing to 12 volts except the condensor in the distributor and I was wondering if I should have put in a 12 volt condensor. Could that be causing my problem. Has anyone out there had a similar problem when converting to 12 volts.

Cheers

Tony

[Frank v R]

have you done a compression test and what type of fuel are you running down there do you still have leaded fuel? sounds like your engine is going away, if you are running unleaded fuel have you been using lead additive? if it is your engine and it comes out make sure you have hardened exhaust valve seats installed ,first thing try adjusting your valves and see what happens, also do you have ethanol in your fuel down there , this stuff is a even bigger problem for the old engines and fuel systems, hope this helps,
regards Frank

[motto]

Condensers are not specified in Volts, they are specified in Micro-Farads which is a measure of storage capacity.

The easy check for condenser compatibility is to observe what sort of a spark the ignition system is putting out. This can be done statically by removing the distributor cap and flicking the points open with a finger nail whilst holding the end of the king lead from the coil that normally plugs into the centre of the cap close to any metallic part of the engine. You should have a fat blue spark that will jump at least 3/8 of an inch. Watch out for Shocko if you have a weak heart.

The spark can also be checked with the engine running by removing one plug lead, starting the engine and once again holding the end near a metallic part of the engine. Depending on what sort of end is on the lead you may have to insert a bolt as an electrode.

The problem you are having may in fact be your plug leads if they are of the silicon type. They are good when they are new but can break down internally and give lots of trouble.

David

[Little Jo]

Hi Frank and David

Thanks guys for coming back to me. You have both given me some things to check out. It sure is a pain as when the Jeep is standing still I can rev her up and down with no change, very responsive, but under load when driving is causing the loss of power and causing the spluttering.

FRANK. The fuel we are sold down here is all unleaded, there is some cheaper unleaded which has Ethonal in it, but I don't use that not even in my normal everyday Jeep. You mentioned a lead additive, I will follow up on that. An old guy told to me to throw a cup full of diesel fuel in the tank and mix it with the other fuel, he claims this will bring the Octane Level down.

DAVID. I will check the spark output as you suggested, If I get a boot who knows I may end up with curly hair. I had already replaced it with new Spark Plugs, High Tension Leads, Coil and Points, however I did not replace the condensor and god knows how old that is.

Cheers

Tony

[Richard Coutts-Smith]

Hi Tony,
The only time we had a Jeep with similar problems it was a lack of fuel to the carby under load. Maybe worth checking filter and lines etc.
Some of the guys here use a bit of diesal in the fuel as they believe it helps prevent valve wear. Certainly never seen it cause any problems.
Personally I use a Moreys product in my toys, and whenever (finacially) possible I use the mid range octane fuel, and have no intention of going down the ethanol path. (Although I did use it for years on my EL Ford).
Have fun.......
Rich.

[Little Jo]

Originally Posted by Richard Coutts-Smith

Hi Tony,
The only time we had a Jeep with similar problems it was a lack of fuel to the carby under load. Maybe worth checking filter and lines etc.
Some of the guys here use a bit of diesal in the fuel as they believe it helps prevent valve wear. Certainly never seen it cause any problems.
Personally I use a Moreys product in my toys, and whenever (finacially) possible I use the mid range octane fuel, and have no intention of going down the ethanol path. (Although I did use it for years on my EL Ford).
Have fun.......
Rich.

Hi Richard

Good to hear from you again. I am always pleased with the advice you guys give me. This morning I started checking eberything again from the start and I followed some of the tips from Frank and David. Took the Carbie off again and gave it a good cleanout and used the compressor to blow out all the little holes and put it back on the motor. Checked the spark as suggested and all the cables, redone the gaps in the spark plugs and points in the distributer. I then replaced the condensor with a new one and took the Jeep for a drive. I was very pleased with myself as the problem is now gone, the only problem is I don't know what I did to fix it, but I suspect it was a faulty condensor. I think I will put some diesel in the tank when I fill up, as you said it can't do any harm. So once again my fellow MLU'r have come to my aid. Thanks guys.

Cheers

Tony

[hrpearce]

Tony I use flashlube adative in the blitz it comes in a measure bottle and is easier than guesing on a quantity of diesel that is safe.

[Little Jo]

Originally Posted by hrpearce

Tony I use flashlube adative in the blitz it comes in a measure bottle and is easier than guesing on a quantity of diesel that is safe.

Hi Robert

Thanks mate, I will get some, sound an easier way to go.

Cheers

Tony

[TCLARK]

Acondenser that is not working will make the points get so hot that they can actually melt. I know this from experiance

[Bob Moseley (RIP)]

Hi Tony - I told you to stay 6v, as it wasn't broke, why try to fix it. Anyway you know how pedantic I am with restorations. And echoing Robert's words, and I think I mentioned it to you, Flashlube is the way to go.

Bob

[Blackpowder44 (RIP)]

I have owned my jeep since 1980 and when unleaded fuel came in I smiled when everyone panicked and wanted hardened valve inserts.The jeep engine was developed well before lead was added to petron universally. You may harden the valve seats but that does nothing regards upper cylinder lubrication or valve stem lubrication, I suspect that you may have a timing issue as the dissy.needs to be altered to time it up for unleaded fuel. On the subject of adding diesel, last year I went around garages that had sifoned petrol that people had put itno their diesel cars, I ran my jeep all season on this and my theory is this, some diesel reached the valve stems as well as the upper cylinder bores, also some sat on top of the pistons and formed a better compression. The only thing to watch is that some may find its way into the sump and dilute your oil, I havnt put this very well but it all worked for me, yours, John.

[Little Jo]

Originally Posted by Blackpowder44

I have owned my jeep since 1980 and when unleaded fuel came in I smiled when everyone panicked and wanted hardened valve inserts.The jeep engine was developed well before lead was added to petron universally. You may harden the valve seats but that does nothing regards upper cylinder lubrication or valve stem lubrication, I suspect that you may have a timing issue as the dissy.needs to be altered to time it up for unleaded fuel. On the subject of adding diesel, last year I went around garages that had sifoned petrol that people had put itno their diesel cars, I ran my jeep all season on this and my theory is this, some diesel reached the valve stems as well as the upper cylinder bores, also some sat on top of the pistons and formed a better compression. The only thing to watch is that some may find its way into the sump and dilute your oil, I havnt put this very well but it all worked for me, yours, John.

Hi John

What I like about our forum is the various options that can be applied and what works for some and that others had not heard of or done. This brings me to another sublect I have been wondering about. When I restored my Jeep I was told not to use the modern Anti Freeze Green Coolant in my old Jeep motor. I have been using rain water in my radiator. However I have been following a lot of different MLU forums and I have seen some photographs showing that the modern Green Anti Freeze Coolant is used in old engines by some MLU members. The question is do I stick with rain water or can I use the Green stuff that is used in modern engines.

Cheers

Tony

[Blackpowder44 (RIP)]

Originally Posted by Little Jo

Hi John

What I like about our forum is the various options that can be applied and what works for some and that others had not heard of or done. This brings me to another sublect I have been wondering about. When I restored my Jeep I was told not to use the modern Anti Freeze Green Coolant in my old Jeep motor. I have been using rain water in my radiator. However I have been following a lot of different MLU forums and I have seen some photographs showing that the modern Green Anti Freeze Coolant is used in old engines by some MLU members. The question is do I stick with rain water or can I use the Green stuff that is used in modern engines.

Cheers

Tony

NO. use only the old blue anti freeze, there is a whole page of info somewhere on the internet,Have just googled anti freeze in old engines and found all the info that you will need to make up your mind, John.

[Dave Page]

Hi Guys,
I have no idea how many times I have heard the -must harden your valve seat talk - because there isn't any lead in the fuel. For engines of WW2 vintage this is not true for several reasons. First, engines of our period were developed to run without lead, Tetraethyl lead was added during the war to -boost- the octane level (more on that later) this was done to reduce engine knock/pre-ignition.
Secondly, the engines are of low compression and therefore do not generate the heat that one finds in modern (post-50's) engines, which could damage valves or seats.
Thirdly, the lead salt deposits actually damage the valve stems and can foul spark plugs; decoking was common practice in part because of this.

Now, back to the octane boosting, when the octane level is increased the burn rate of the fuel is actually slowed down. Think of it like this, a low octane fuel will burn -very- quickly, the resulting explosion will drive the piston down quickly as if struck down by a large hammer. Whereas a high octane fuel will burn slower and the resulting explosion will push the piston down as the fuel is still burning. This means less pressure and stress on your old toy.
By-all-means add an octane booster to your fuel, one with a top-end lubricant is also cheap insurance for flathead (valves in block) types. I have an Indian 741 and it runs so much better with a drop of Blendzall gold. My Daimler also runs better with a mix of the above product, though it is OHV so the top-end lube is probably overkill but she runs fine. If you feel you must add lead then go ahead but just be aware of what is going on.
Cheers,
Dave

[Blackpowder44 (RIP)]

Originally Posted by Dave Page

Hi Guys,
I have no idea how many times I have heard the -must harden your valve seat talk - because there isn't any lead in the fuel. For engines of WW2 vintage this is not true for several reasons. First, engines of our period were developed to run without lead, Tetraethyl lead was added during the war to -boost- the octane level (more on that later) this was done to reduce engine knock/pre-ignition.
Secondly, the engines are of low compression and therefore do not generate the heat that one finds in modern (post-50's) engines, which could damage valves or seats.
Thirdly, the lead salt deposits actually damage the valve stems and can foul spark plugs; decoking was common practice in part because of this.

Now, back to the octane boosting, when the octane level is increased the burn rate of the fuel is actually slowed down. Think of it like this, a low octane fuel will burn -very- quickly, the resulting explosion will drive the piston down quickly as if struck down by a large hammer. Whereas a high octane fuel will burn slower and the resulting explosion will push the piston down as the fuel is still burning. This means less pressure and stress on your old toy.
By-all-means add an octane booster to your fuel, one with a top-end lubricant is also cheap insurance for flathead (valves in block) types. I have an Indian 741 and it runs so much better with a drop of Blendzall gold. My Daimler also runs better with a mix of the above product, though it is OHV so the top-end lube is probably overkill but she runs fine. If you feel you must add lead then go ahead but just be aware of what is going on.
Cheers,
Dave

Thank Christ there is at least one of us on here that understands our old engines and leaded or unleaded petrol. John.

[Richard Farrant]

Originally Posted by Dave Page

I have no idea how many times I have heard the -must harden your valve seat talk - because there isn't any lead in the fuel. For engines of WW2 vintage this is not true for several reasons. First, engines of our period were developed to run without lead, Tetraethyl lead was added during the war to -boost- the octane level (more on that later) this was done to reduce engine knock/pre-ignition.

Dave,
You may not be aware, but quite number of military vehicles built during WW2 were fitted from new with hardened valve seats, to give a few examples, Dodge WC models, Austin K5 and K6, Morris Commercial four cyl engines, etc. so nothing wrong in fitting them now. If a valve seat is recut too many times it pockets, then the exhaust valve suffers burning as the hot gasses cannot freely escape. By fitting hardened seat on overhaul, it is a fit and forget operation as with the low use most of these vehicles have it will reduce the times a head is lifted to attend to burnt seats.

[Dave Page]

Hi Richard,
at risk of hijacking this thread - I was not aware of the specific use of hardened seats, and was talking in general. I should also have added that if you drive your old machine at period speeds for short runs then there should not be a problem.
Cheers,
Dave

[Lynn Eades]

Back to the condensor.
Tony Generally speaking the condensor is matched to the coil. If the condenser is over capacity or under capacity it results in arcing at the points (contact set) and a transfer of material (platinum) to one or the other side, resulting in a short life to points. (btw, vented points are a better option if available)
If the condensor is u/s.(i.e. completely stuffed) it will often leave the points burned black.If it still goes, it won't for long. They should be a clean grey. (the only other possibility here is oil getting into the points)
You will probably notice that 6 volt condensors are bigger than 12 volt condensors. (this might be an age/ construction thing, all the same, its a good guide)
Sometimes you can buy one with the microfarad value stamped into the body, and in some cases they were available in different values for the same application.
Having converted to 12 volt you should change the condensor for one made for a 12 volt application. Any one you can get in the hole, and hook the wire up will do. All you need is the thing clamped or screwed to the distributor body, and the wire hooked up to the feed to the points. You will notice that the early jappers had them on the outside of the dizzy. Keep an eye on the points, and try a different condensor if they are tranfering metal faster than they should. The local auto electrician might be able to help regarding capacity up or down. If your coil came from a certain type of vehicle, a condensor of the same capacity, as that vehicles condensor, will do the trick.
I vaguely recall seeing in a wartime training pamphlet, teaching the drivers to make a tempory condensor using a bean can and paper. Maybe someone can recall.
Anyhoo you have it sorted. My guess, from your description, fuel.
Hopefully this has filled a few knowledge gaps, for some of the would be mecanical lurkers out there.

[motto]

To change tack a little bit Tony there is 'Another Way' and that is to install electronic ignition which I would thoroughly recommend to anybody. I've installed it on my '43 Dodge 6x6 1-1/2 ton and am very happy with it. No more condenser or points problems forever. Set and forget.

David

[Little Jo]

Originally Posted by Lynn Eades

Back to the condensor.
Tony Generally speaking the condensor is matched to the coil. If the condenser is over capacity or under capacity it results in arcing at the points (contact set) and a transfer of material (platinum) to one or the other side, resulting in a short life to points. (btw, vented points are a better option if available)
If the condensor is u/s.(i.e. completely stuffed) it will often leave the points burned black.If it still goes, it won't for long. They should be a clean grey. (the only other possibility here is oil getting into the points)
You will probably notice that 6 volt condensors are bigger than 12 volt condensors. (this might be an age/ construction thing, all the same, its a good guide)
Sometimes you can buy one with the microfarad value stamped into the body, and in some cases they were available in different values for the same application.
Having converted to 12 volt you should change the condensor for one made for a 12 volt application. Any one you can get in the hole, and hook the wire up will do. All you need is the thing clamped or screwed to the distributor body, and the wire hooked up to the feed to the points. You will notice that the early jappers had them on the outside of the dizzy. Keep an eye on the points, and try a different condensor if they are tranfering metal faster than they should. The local auto electrician might be able to help regarding capacity up or down. If your coil came from a certain type of vehicle, a condensor of the same capacity, as that vehicles condensor, will do the trick.
I vaguely recall seeing in a wartime training pamphlet, teaching the drivers to make a tempory condensor using a bean can and paper. Maybe someone can recall.
Anyhoo you have it sorted. My guess, from your description, fuel.
Hopefully this has filled a few knowledge gaps, for some of the would be mecanical lurkers out there.

Hi Lynn

The condensor I replaced was about the same diameter as the old one I removed and accoding to the guy at the auto shop would match the new 12 Volt Bosch Coil I installed. Having rechecked everything again all I can say the problem is gone and my Jeep now has plenty of grunt. Tomorrow I am taking her out on a long club run so fingers crossed this will be a good test run.

Thanks to all you MLU guys for the very interesting advice and suggestions. It is fantastic for a novice like me to have so much information to learn and remember. I really do appreciate it. You guys in MLU are so supportive and have always been there to assist and help me and I guess this is why I enjoy my new found, and very addictive hobby.

1st Photo is the old Condensor
2nd Photo is the new installed Condensor.

Cheers

Tony

[Little Jo]

Originally Posted by motto

To change tack a little bit Tony there is 'Another Way' and that is to install electronic ignition which I would thoroughly recommend to anybody. I've installed it on my '43 Dodge 6x6 1-1/2 ton and am very happy with it. No more condenser or points problems forever. Set and forget.

David

Hi David

My younger brother suggested that to me as well. I think that is something to think about. I Know there are a lot of restorers who would not agree as they would like to see everything original, but technology has marched on and I guess we have to move with the times when all else fails.

Cheers

Tony

[Mike Kelly]

Tony

For most automotive applications , you want a value of around .25 uf for the ignition capacitor .

1 uf = 10 to the power of negative 6 ... which is one millionth of a farad

Michael Faraday had something to do with it I think

[Bob Estabrooks]

This thread went into several dierctions. After 15 plus letters I had a problem determining whats the prob .

Consider this. 6 V starter , 12 battery. Crank like hell and start engine. Idles.
Under load misses. I would suggest the battery is not supplying sufficent power to energise the Ing. system under load. Check the charging system. Bob

[Little Jo]

Originally Posted by Bob Estabrooks

This thread went into several dierctions. After 15 plus letters I had a problem determining whats the prob .

Consider this. 6 V starter , 12 battery. Crank like hell and start engine. Idles.
Under load misses. I would suggest the battery is not supplying sufficent power to energise the Ing. system under load. Check the charging system. Bob

Hi Bob

After all was checked, the culprit turned out to be the Condenser, problem solved and I am a happy chappie.

Cheers

Tony