head gasket

[mallard]

hi, I'm new to this site but have found lots of helpfull things on here and over on the old 503, I got my mutt back it 2007 and it has been fairly problem free since then. I recently pulled my 151 out and the batteries were dead, i pull started it and as soon as it cranked it started billowing white smoke out of the exaust. i let it run for 2-3 min to see if it would clear out but it wouldn't. it had been sitting for about 6 months. it looks like there is an new leak and oil is coming out the back of the engine where the head is now. for a while i have had oil seaping out of the passenger side at the base of the head between the 2 and 3 cylinder. I assume my head gasket is gone so what i need help with is verifing this is the problem and then i will need help with the repair. FYI i have never torn apart a motor before but i am fairly good with tools and at least want to see what is involved with fixing this and see if i want to attempt to repair it.

also i believe mine is a '64 A1 (its not here, its at my parents shop about an hour away). I mainly use this for hunting season and riding around on the county roads. my ultimate goal (2-3 years) is to strip it down remove the roll bar, repaint, then change all bushings and seals, u-joints and put it back together after i build my shop at home this winter. I just finished rebuilding the winch and just finshed rewelding some of the bad welds the p/o had on the bumper. here are a few pictures of the jeep and the oil leak. sorry for the long post just trying to give all of the details. Thanks and have a good evening.





















and here is after the rebuild of the winch i will put back on it.

[rickf]

Not a bad looking vehicle. I have an 8274 winch, used it hard for 35 years before the motor finally died. Have to get a new one. The bad news for you is that winch will tear the front right off of the 151! It is only unibody sheet metal up there. No frame. They never had winches on them. As far as the head gasket goes it is hard to tell from the pictures, they just look like a valve cover leak but your description of the smoke is definitely a head gasket. It is not a hard job at all and is a common failure on these. When you are ready to do it let us know and we can walk you through it. Start to finish even never having done it is a one day job and that includes the clean up and beer afterwards. There will be a couple of things you will need to get ahead of time.

Rick

[Hambone]

Welcome to the G, Mallard, we are neighbors, I'm in El Dorado. Hambone

[Horst]

As Rick says, pretty simple and straightforward. Make sure you have the technical manual. Will tell you how to remove the head, which is only disconnecting exhaust, removing carb and ignitor, a few lines and then loosening the head bolts. More important gives you correct torque values for re-assembly. Only thing you need is a new head gasket, adhesive copper spray and a torque wrench.
I would not touch the exhaust manifold if it is still without leaks as the mounting bosses tend to crack on the earlier heads. Bolts can also be a nightmare and will snap right off when touched.

Before you start putting a wrench on it however, give it a good clean with degreaser and a pressure washer.

Only thing I disagree with Rick is that I don't believe it is a day job. He says including beer but that would include a lot of drinking to make is last so long. If you don't snap a bolt in the process...

[rickf]

I am curious how you are running the winch on the 24 volt system? If you are using just one battery then you will cook the other battery by overcharging it due to the imbalance between the batteries.

[mallard]

Thanks for the help so far. Rick I saw the thin mounting spot it is hooked to and I believe you are correct it would rip off if I tried pulling a full load. 95% of the time when I use the winch it is to stand a deer stand up, drag a tree out of the road etc. I try to not get this stuck. probably never using more than 2-3k pounds pulling. I do have it hooked up to just one battery but in the last 7 years I have had no problems and my batteries are now 6 years old but i believe are on the way out the door. also I use a duel bank battery charger on them most of the time it sits. but I bet the winch doesn't get used more than 5-10 times a year.

as for your 8274 they do last a long time and sorry to hear about your motor, here are a few PN that could help you. the 4.5 hp motor now is a pn 7536 or you can put a larger 6.0 hp motor pn 68608 on it. if yours is 35 years old the motor shaft is probably keyed and would need the updated splined pinion pn 15879 as all of the new motors are splined now.

Hambone, I've spent a lot of time down in the El Dorado area, My Wife is from Old Union and her family still lives down there.

I will download the TM from the WIKI and probably print it out and put it in a big binder, can any of you remember the est. torque, i don't have a mid range torque wrench, i only have in/lb and 25-250 lbs, just wondering if its time to get a 3/8 torque wrench.

I am going to bring it to my house in the next few weeks and will start cleaning it up. It sounds like this can be done with out pulling the motor out? Thanks again!

[rickf]

The torque wrench you have is fine and thanks for the part numbers. I think I have one of the first with the splined shaft. I have the first version with the automatic brake without the cables. Those brake pucks and the bushing to work it all can be a pain. I am just now putting my CJ-7 back on the road and that is what the winch is on. By the way, ALWAYS pull straight ahead and you will have better luck in not bending the front end of the 151. As they get rusty inside those rails, and they do, it will take a lot less than 2000 lbs. on a little bit of an angle to bend it badly.

[mallard]

Well i brought my mutt home this weekend and spent 2 hours presure washing the outside, inside, motor and even underneath and got all the 50 years worth of greese and mud out from under there. Then i cranked it up and it had white smoke pretty good for about 10 min, then it started to clear up and after about another 10 min was completely gone!!! What would have caused that?

I did find a couple leaks though after i washed the moter and ran it.

1st is the rear most on the exaust manifold (i could see smoke coming out when first cranked up) but from reading this is a crap shoot to change? is this right?

2nd on driver side of the motor i could see tiny bubbles coming out at the red arrow



3rd is underneath the distributor at the red arrow



can you help with what gasket i would need for this?

also here are a few pictures of it all cleaned up!

[Horst]

You will need a new head gasket. For the oil leak on the right side under the distributor, I believe there is an O-ring, but check the -34P manual to be sure. Mark the position of the ignitor, remove that single bolt at the bottom of it, remove ignitor and then you can easily access the adapter holding it. That itself is secured with two bolts which are now accessible. Replace O-ring and re-install adapter. Leave ignitor off as you want that out of the way when removing the head. Re-install later at same position, run engine and check timing with a timing light. To do so, remove #1 shielded ignition wire and replace with a piece of ignition wire and just stick it into ignitor and spark plug. This way your pick-up of the timing light will work fine. No need to create any adapter or so.

Everything so far can be done with the engine installed but I would still consider pulling the powerpack . You have some transmission leaks too. Most of them can be fixed with the tranny in the truck but with the powerpack out, it is so much easier and quicker. Pulling it the first time, it will probably take you 4 hours or so. With some practice, powerpack is out within an hour or less. The nice thing about a 151 is that you pull engine with all accessories (radiator, carb, generator, starter) and transmission as a unit. Only time consuming is disconnecting the various hoses, exhaust and drive shafts and then remove brush guard. Can be done in a one man operation.

Looks like in the long run some welding is required. Seems like it was cut. Rear fender tops do their job but aren't nice. Good thing that these are now available from a member of this site (Guy).

[rickf]

Not bad looking. The leaks are easy enough to fix. Are you planning on restoring it to original or running what you got? There has been a lot of body modification so if you go the restoration route you have your work cut out for you. You also have a lot of electrical work from the looks of it. The white smoke was most likely oil and antifreeze that had accumulated in the cylinders and exhaust over the time it sat. I am guessing the cylinder with the leak must have had the piston up or otherwise you would have had a hydrolock situation where the cylinder was full of water and it would not turn over.

[mallard]

Thanks for the help, I will still go ahead and change the head gasket and also the o-ring. also I have several more leaks I would like to get fixed before winter. I know the rear main seal is leaking, the transmission but not sure where, i'll need to clean it up better so I can tell. also both diffs leak but again need to clean it up better to see which seals leak.

as far as the restoration goes I don't have the skill set or the patience to do some the same top level work I've seen some here do. my goal for this is to have it where it runs great and everything works and bring as many components back to original as possible. I will probally leave the incorrect body panels for now. the wiring is going to be a bear as the P/O mixed and matched 12v and 24v components. what I can tell so far is the external fuel pump, ignition, head lights, starter and gauges are 24v and it has a different brand 24v alternator. the front blinkers, rear tail lights are 12v. I started last night removing some of the 12v wires that are not in use to help clear up some space and confusion.

it has also been painted many different colors over its life, starting by OD green, then blue, then hunter green and now flat green. after the mechanical side is fixed I would like to blast the body, re-weld as needed, then new bushings, shocks springs and paint. but I am planning on doing this in stages over then next couple years.

I would also like to re wire and go to the correct lights and switches all around but that will depend on being able to find a good A1 front harness. Thanks again for the help and I'm going to go ahead and get the head gasket, o-ring, and rear main for now.

[mallard]

double post

[mallard]

well good news and bad news. I tightened the bolts below the distributor and it quit leaking. also i don't believe i had a rear main leak to begin with. I believe i was seeing the distributor o-ring leak as it dripped all the way to the back bottom of the oil pan and thinking it was the rear main. so at this point no more having to pull the motor.

i decied it would be a good idea to change all my fluids, i drained and filled the diffs, and trans and then tried to get the drain plug out of the motor, it was real tight and when i was pulling on the ratchet i noticed i cracked the oil pan just about the threads and oil started to leak. so now i'm back having to pull the motor.

i started taking everything loose tonight but i've run into a snag. I went to disconnect the front motor mounts but i cannot find a nut to grab onto? is there a trick to this? the bolt comes in from the top, through metal, then the rubber, then metal and then it doesn't come out the bottom rubber? any thoughts, thanks.

[rickf]

The nut is part of the lower mount, same with the transmission mounts. I have had some really tight oil drain plugs and I have put some serious torque on them and never cracked a pan with the exception of one that had water in it and had rusted on the inside. You might just want to get yourself a complete engine gasket kit and do that once you have it out. I haven't seen them advertised for quite some time but I am sure there are still NOS oil pans out there. On your engine pull do not forget the speedo cable and ground strap.

[Rainman]

Hey Mallard, here's a video on pulling the power pack in 8 minutes, though your time and results may vary. I have a spare oil pan here in Ohio but it only fits an M151. Don't recall who it was that hammered out the dent in their oil pan the last time, but that dent is there for a reason
https://www.youtube.com/watch?v=XIJ_QCuhwGc
Rainman