Info needed: 1967 M38A1 Lubrication?

[maple_leaf_eh]

Originally Posted by Les Kovacs

...

Wow...thanks for the word of caution.....can you walk through the changing of any gauge (eg-temp) starting at taking off the panel and grounding....not sure when to ground....the actual changing of the gauge and sending unit sounds and look easy.

....

The M-series was designed to be fixed by mortals. If the gauge unbolts and the connection unplugs, that is literally as much work as is required.

BTW, this conversation between you and Rob is worth a Sticky for troubleshooting.

[rob love]

You can change the gauge as Terry describes, but before you turn on the ignition switch, you either have to run a ground to the panel, or else re-install the panel back in place. The best solution is to make up a short wire permanently installed form the dash to the panel.

When installing the gauge, the spide harness (power) goes to the non-ribbed connector of the gauge. The sending unit wire will be ribbed, and goes to the ribbed connector of the gauge. Make sure the retaining bracket is solidly onto the gauge as that is where the gauge gets it's ground.

That little allen key on the back of the alternator is where you can adjust a tiny potentiometer to adjust the alternator's output voltage, should it be too high or low. Some of the alternators (the prestolite AU20003 model if memory serves) also have a terminal inside where you can change the output from 60 amps to 30 amps if you are in hot climates.

[Les Kovacs]

Hi Rob & Terry....thanks for both reply's....I agree with Terry....I am sure that all the questions & responses in this post have been done before.....but probably not all in one place/post....case in point...I have saved all the questions & responses from Rob and et Al in a word document.....when it comes time to actually work on the jeep when parts start arriving....I have the info-details from people that have actually been there as well as following the 3 manuals I bought from Brian Asbury.

OK Rob....another question regarding the shorting of the panel just to confirm...as per you email...."you either have to run a ground to the panel, or else re-install the panel back in place. The best solution is to make up a short wire permanently installed form the dash to the panel."

So, Question....if the panel is off...and you have completed the replacement of the EG: temp gauge & sender you can replace the panel to the dash before you turn the ignition on and you should be golden....correct? It sounds like the bottom line is that you cannot turn on the ignition before you put the panel back on the dash to ground the panel...correct?

les

[hrpearce]

Originally Posted by Les Kovacs

It sounds like the bottom line is that you cannot turn on the ignition before you put the panel back on the dash to ground the panel...correct?

les

That is correct, saves any chance of failure. I would leave the keys on the bench till the work was complete.

[rob love]

Originally Posted by hrpearce

That is correct, saves any chance of failure. I would leave the keys on the bench till the work was complete.

Problem with that is that there are no keys (unless the jeep is modified to have one). Instead there is a lever type switch just itching to accidentally get knocked on during the installation.

[Les Kovacs]

Thanks for both responses....so I will leave ignition off until after replacing panel back onto dash.

PS....I do not have ignition keys.....I do have the dash on/off lever but I also have a green plastic lever in the engine bay next to the starter that all the heavy duty wires go into....its a main power shut off to all electrical in the engine bay...I turn this off along with the dash ignition when not using the jeep.

Regards,

les

[Les Kovacs]

Hi Rob,

I have more questions if you have the time....

I will be adjusting the carb mixture come Sunday....I know that I cannot turn in the screw hard....but, can you please tell me which way is rich & which way is lean....left turn or right turn....I would just like to know what I am doing when turning the mixture adjustment screw.

Secondly, it appears that I have a 67' CDN2 that has had a few updated modifications by DOD aside from turn signals & seat belts....I apparently have the air filter out of a M151 Mutt. If your familiar with them, what is the plastic spaghetti like material in the top of the filter housing and where can I get it new?....its now a little brittle and I am afraid that pieces will break off and get into the carb.

Regards,

les

[rob love]

The screw is right hand thread and when screwed all the way in stops the flow of fuel. So, looking at it from the side of the Jeep, with the engine at operating temperature, you screw it clockwise (inward) until the Jeep starts to stumble, then start backing out very slowly until you reach the highest RPM. Once you start making it too rich, the RPMs will actually drop slightly.

Ideally, you would have a tachometer hooked up, but with the waterproof ignition that gets a little complicated. There are also timing lights with digital RPM gauges on them, but it is actually getting harder to buy a timing light these days.

It was not a modification to have the M151 type aircleaner...that was standard on the CDN2 and CDN3 Jeeps. I have never heard of the plastic "horsehair" coming apart....leave it alone and you will be fine.

[Les Kovacs]

Wow...quick reply...thanks for the more detailed info as per carb adjustment.

Never heard of plastic "horse hair" filtration media...but, if it does not become too brittle and fall apart....I am not worried. I have however poured kerosene into the top half/cover with the "horsehair" in it...swished the kerosene around for 3-5 min then poured out the mean looking goo....did this twice until what came out was somewhat clean....also cleaned the SOS pad like media in the lower half as well as replace the oil at the bottom and cleaned out the whole housing. Hopefully, kerosene was the proper cleaning fluid to use.

Thanks again,

les

[Les Kovacs]

Hi Rob....it has come to my attention that I had an important question to ask as per safety but totally forgot over the last two weeks....it is regarding the front original OE hubs. While at a military vehicle show...while I was away from the jeep my wife was talking to an MV collector (he was showing off a British Scorpion of the early 80's and a 40's Willy's jeep)....he mentioned to my wife that I had better replace my front hubs with a Warn or other selectable hub as the OE hub was known to crack and grenade the front axle (happened to him). He was pretty insistent explaining this to my wife at the time. She has since brought it to my attention again and being that safety is paramount with me I though I would ask you for your opinion. Is this a none issue?... or have there in fact been problems?....or this is a problem but most likely due to lack of proper maintenance?

PS...out of the hundreds of pics of jeeps of all ages I have seen on google & other websites I have never seen one with aftermarket selectable hubs....just all OE hubs.

les

[maple_leaf_eh]

I'm not Rob, but I'll jump in.

Yes and no. Locking front hubs were all the thing in the past for civilian pattern CJs. The hubs serve a purpose, but HMV owners typically do not modify service pattern vehicles to suit civilian quirks. We'll put a roll bar on for safety, but not jack up the suspension for clearance. That said, I don't remember the last time I saw even a CJ with locking hubs, so either tastes have changed or technology has gotten better.

[rob love]

Les:

He is likely talking about the axle knuckles grenading, which was applicable to the older knuckles with 4 large ball bearings acting as the U-joint. With a bit of wear, and a full turn, a ball could pop out, and the force of the jeep was now pushing against a locked up knuckle. It usually happens at slower speeds since any full turn over about 18 miles an hour results in a Jeep rolling over.

Good news is that there is a 99% chance your Jeep has the more simple standard Cardan type U-joint. That is to say that, inside that knuckle is a normal universal joint much like your drive shaft. It does not have seals on it like a drive shaft U-joint. Instead the knuckle is packed in grease. In all these years, I have never had to replace a U joint on a CDN2 or CDN3 front axle shaft.

So don't bother with the locking hubs. That said, I did see some of the earlier knuckles find their way onto the Cdn2s. That is where the 1% comes in. There was an overlap for several years between the 52 and 53 Jeeps and the CDN2 and CDN3, so if there would be a problem in the front end, the whole axle or axle shaft could get changed with an earlier assembly or component.

On the earlier Jeeps with the early knuckles, the axles can be changed up to the more modern type, but usually guys do not do that until they have experienced the failure.

[Les Kovacs]

Thanks Rob & Terry for your input on my last "hub" question.

Rob......update on the rad/coolant/temp issue.....so, before work on the cooling system (old coolant, old leaking water pump, puking rad coolant after shutdown, temp gauge always fogging up and no thermostat whatsoever, the temp gauge never read over 140 F.)
Now, after professionally flushing the rad, adding in a 160 F thermostat and a new 3 pulley water pump and adding new coolant at about 60/40 coolant to water ratio regardless how the jeep is driven, the temp gauge rarely fogs up, the rad never pukes coolant anymore, however, the temp gauge now always just gets a hair past 180 F (never any higher)...why? and what may be the issue?....bad thermostat?.....bad temp gauge? or bad sender?....just after shutdown the rad coolant temp at the rad cap always reads about 155-160 F.
Is the thermostat not opening?

Thanks,

les

[rob love]

If the temp is truly 185*°, that is not a problem, the cooling system is fine at that temp. Did you try a mechanical gauge to confirm that temp though?

I had our ceremonial M38A1cdn3 out for a run the other day and it too runs at 185*°. I can't say what mine runs at....unless it crosses the 200 mark I don't consider it a problem. The real problems start at around 230 to 240, when the coolant will start to boil.

[Les Kovacs]

Hi Rob....no, I have not tried a mechanical gauge as I do not know how and I have never seen a mechanical gauge that replaces a proper sending unit.

As previously mentioned, several times right after shut off I cracked the rad cap and quickly put in a temp gauge meant for fluid immersion and the temp is always at 155-160F.

Where can I get a mechanical gauge and where does it plug in?

Also, why would the average coolant temp rise from 130-140 F to 180-185 F after having the rad flushed, a thermostat installed and a new water pump?

les

[rob love]

http://www.ebay.com/itm/NEW-SuperPro...UAAOSwZQRYbUaW

Temp went up because you installed a thermostat. What we need to do now is determine if you have the same readout between your thermometer and your gauge. Then again, one has to ask why? You are not having any problems now...perhaps quit chasing the red herring and enjoy the Jeep.

[Les Kovacs]

Hi Rob....thanks for the quick response...your right.....I should be enjoying the jeep which I am....almost every warm/dry day my wife and I go out for a 10-20 km drive....the jeeps driveability is a little better after I adjusted the carb mixture-smoother after 1/8 turn counter-clockwise (leaner) as you had explained.
However, as I want this jeep to live a long life with the engine it has I need to know the true engine temp (if the gauge/sending unit is bad it could be reading temps past 200 F and I will never know) as well as the true oil pressure (pressure gauge now reads 50 psi after start and after about 10 min of driving but then after a few more min reads 20-30 psi when driving)....so I am somewhat anal when it comes to true engine operating parameters.

Another question...I shift by sound and jeep vibration....I usually shift to 3rd at around 25 MPH (if gauge is somewhat accurate) but get a mild shudder until about 35 MPH....is shifting to 3rd at 25 MPH lugging the engine?....when are your shifts?

Many thanks,

les

[Les Kovacs]

Hi Rob....as per one of your earlier posts/reply's to my questions you had mentioned that a 13/16 deep socket was required to un-screw the spark plugs...I purchased a 13/16 deep socket at Princess Auto....the socket was the deepest at 3.0 inches overall length....it does not fit....it appears that a socket to fit the depth of the plugs would required an additional 1/4 inches of length. Any idea where to buy a longer(3.25 inch long) 13/16 deep socket?.....I really do not want to spend $40.00/US to order a special plug socket wrench if I do not have to.

Thanks for all the other great ideas and tips.

les

[rob love]

Both proto and gray brand 1/2" drive deep length sockets will do the trick. There will no doubt be others. Forget about spark plug sockets, they are too short internally.

I just went to the tool box to try some others out, and my 1/2 dr princess auto socket only barely makes it onto the hex, so I won't reccoment that socket. However I tried a westward 3/8 drive 13/16 socket and it fit well. Part number is DS386K.

Best bet is to take a spark plug to the tool store with you and try some out. Plugs are not in that tight, so you don't need top quality.

[Les Kovacs]

Thanks for your response....I will try NAPA and if all else fails I will scour Barrie's auto shops for a longer 13/16 socket....many thanks!

PS...Jeeps goes into shop tomorrow for rear pinion seal and add a leaf to the driver side rear spring pack....which leads me to my next question....even without the add leaf to the passenger side (carried 200 lbs of radios) the angle of the "U" joint and shaft coming out of the transfer case seems somewhat drastic....how much angularity can the joint handle?...(jeep already comes with standard 12 leaves per rear pack).

Also, I ran across a few posts of some people drilling a 1/8 inch hole in the skirt of their thermostat....why?

Regards,

les

[rob love]

Originally Posted by Les Kovacs

Thanks for your response....I will try NAPA and if all else fails I will scour Barrie's auto shops for a longer 13/16 socket....many thanks!

PS...Jeeps goes into shop tomorrow for rear pinion seal and add a leaf to the driver side rear spring pack....which leads me to my next question....even without the add leaf to the passenger side (carried 200 lbs of radios) the angle of the "U" joint and shaft coming out of the transfer case seems somewhat drastic....how much angularity can the joint handle?...(jeep already comes with standard 12 leaves per rear pack).

Also, I ran across a few posts of some people drilling a 1/8 inch hole in the skirt of their thermostat....why?
Regards,

les

The angle of the drivetrain is just fine. I have never dealt with any significant damage to U joints or rear driveshafts on the M38A1s.

The hole is likely peoples attempt to make a bypass so there is flow, preventing hotspots within the engine. Really not neccessary, since all the military Jeeps have the bypass hose running from the head to the water pump. We didn't do that in the military....really no reason for it.

[Les Kovacs]

Rob....thanks for clarification.

The jeep got a new pinion seal this AM....took only 30 min....I let the mechanic know where to apply the RTV as per your earlier suggestion....drove home and so far no leak/weep....the old seal did not have any rubber seal left at all. Old one used to leak standing still overnight....gave me a chance to change diff oil again as the first change (two weeks ago) oil came out like malted milk.

With new add a leaf on the driver side both sides now measure 37 inches to top of rear fender well. Mechanic did say that now with 13 leaves there is no issue with U joint-over-angularity at diff or coming out of the transfer case.

PS.....with all this priceless knowledge about M38A1's, I assume you had something to do with the vehicle maintenance in the military....if so, thanks for your service!

Regards,

les

[maple_leaf_eh]

Originally Posted by Les Kovacs

....

PS.....with all this priceless knowledge about M38A1's, I assume you had something to do with the vehicle maintenance in the military....if so, thanks for your service!

Regards,

les

My service was to drive around in these vehicles as a teenager and into my early 20s, learning about soldiering. Since then I've owned a few M38A1s, one of which Rob surveyed for its faults. My current money-pit is a 1974 Pattern M151A2.

[Les Kovacs]

Interesting....I would not mind owning a M151....however, they never come up here in Ontario....keep looking at kijiji & other sites but no luck....M38A1's and older MB's come up every once in a while but never M151's.

les

[maple_leaf_eh]

Originally Posted by Les Kovacs

Interesting....I would not mind owning a M151....however, they never come up here in Ontario....keep looking at kijiji & other sites but no luck....M38A1's and older MB's come up every once in a while but never M151's.

les

Mine turned up on Kijiji in Edmonton, and was publicized here on CGN.

[Les Kovacs]

I am now confused about which spark plugs to use....I finally pulled the plugs from my M38A1-CDN2...the first plug closest to the rad was an Autolite 2245...the rest of them were Autolite 2243.....all 4 came out well and all 4 had a light tan colored resistor/ceramic (is this good?).

OK...so which spark plug (Autolite 2243 or 2245)is correct for this application (F head) as I am confused. An on line jeep store sent me Autolite 2243's a month ago before I realized that there may be other more appropriate applications.

Thanks for your response.

les

[rob love]

2243 is the equivalent of the old Auto-lite AR5s, which is the cold plug. If you have an oil control problem, or the plugs foul up, then 2245 (AR7s) is the plug to use.

There are also the Champion XMJ14 and XMJ17 which are interchangeable. The Champions now use a new number which I don't know off the top of my head but is easy enough to find.

My information is that Autolite is no longer making the 2245, and may have also dropped the 2243, so it is going to get a little harder (and expensive) to get plugs in the future. I can still get 2243 plugs at under $13 a plug. The Champions are up around $28 a plug with a trade price of arouns $18.

[Les Kovacs]

Thanks Rob....I guess I will be buying more 2243's....the plugs were not fouled (all three 2243 & the single 2245 I took out) in fact they were all nice light tan on the insulator suggesting a clean burn....which leads me to my next question....then where is my oil going?.....I am loosing about 1/2 a quart of 15W40 in approx. 200-300kms. There is no visible oil in the coolant (which has remained new looking and bright green), the exhaust does not blow blue smoke on start-up (valve seals) nor smokes on the drive....I leak 1-2 drops per day from the area around the rear main seal and that's it. Where is the oil going?

Regards,

les

[rob love]

1/2 a quart in that time/mileage period is quite bad. You have covered the only 3 places it could go. Leakage standing still is not relevant, especially one to two drops per day.

Take a measuring cup and fill it with a half liter of water. Pour that on the ground and you'll see just how big a puddle you are talking about. Huge.

So either you are burning it, or leaking it. I would suggest leaking. Run the front wheels up on a pair of those little metal Cdn tire ramps like you might use for an oil change, and leave the vehicle running. Now you will see what the true oil leakage will be if it is from the rear main.

If it is not leaking then it is burning it. You have no idea how old those plugs are......they could have been changed a week before you bought the Jeep. Try a compression check. Cylinders should be at 120-125 each with the engine warm. Anything lower will indicate worn rings. What I normally found was that the cylinders would deeply score. These old engines have a very long stroke, and the scoring would go all the way from the top to the bottom, and deep.

In my experience, once compression was below 115, you were in trouble. At 110 consumption would get very high, and at 90 you will have trouble just to get the Jeep to start on a cold day.

Perhaps that is why you had a 2245 plug in the one cylinder?

[Les Kovacs]

Thanks for your patience....I am under the jeep several hours a day and I can tell you there is no engine oil leak anywhere (I have cardboard under the jeep 24/7) with the exception of 1-3 drops from the rear main seal.

Only the first plug was a 2245...the remainder were 2243's...and all had the same light colored tan insulator and electrode suggesting even burn/ignition in all cylinders.....your opinion?

Also, no visible blue smoke on start or while driving.

What about a blocked PCV valve?

Last question....brake fluid.....where to add and what type...dot 3?

Regards,

les