Smoking Engine - Valves?

[Nick_]

My Jeep sat untouched for over a decade. The M151 engine is smoking a decent amount. Upon startup there is a blue-tinted smoke, and it smells pretty awful. When the Jeep is outdoors it's noticeable, and inside a garage it'll smoke you out within a minute.

I understand there are a few causes of smoke. I did a compression check and found 125 lbs. across all cylinders, cold engine with no oil tricks. This leads me to believe the piston rings should be good. Therefore I'm guessing a valve job is in order? I found this kit from Army Jeep Parts: https://www.armyjeepparts.com/p-3225-m1 ... -3190.aspx that covers just about everything.

I'm not looking to fully rebuild the engine and go crazy, just a little trail rig. Normally the smoke wouldn't bother me but I think the smell would prevent others from following. On a side note, my engine seems to be sucking down the gas? I replaced the fuel pump and it no longer drains in the crankcase, but it'll empty 1/2 gallon in a couple minutes.

Video 1 outdoors: https://www.youtube.com/watch?v=EzvfpPw25BM
Video 2 indoors: https://www.youtube.com/watch?v=NJuKw9elJ3o
Video 3, outdoors first 40 seconds: https://www.youtube.com/watch?v=bcV1FYWfCfs

[svramselaar]

hi

it sounds it runs on 3 cylinders
check if you have sparks on all spark plugs
do you use fresh petrol or old
is the choke valve open


george

[muttguru]

I agree with George. It sounds like the choke is closed. That would cause high fuel consumption.
And if the fuel leaked into the sump from the fuel pump....did you cange the oil and filter? Are you certain the replacement fuel pump is in good condition? These old diaphragms don't last forever

ken

[rickf]

I also have to agree, it sounds like exceptionally rich and missing on at least one cylinder. Bad valve seals will cause blue smoke so that is probably where the smoke is coming from but the missing is certainly not helping. I would say all you really need are the valve seals and a valve cover gasket but the rest of the stuff in that kit is good to have on hand just in case you find you have an intake leak. You might also want to rebuild the carb.
I had to laugh at the string throttle. I ran the last 75 miles off an off road race in a buggy and still finished third doing just that, with the broken throttle cable over my left shoulder.

By the way, that is a very interesting vehicle. Looks like you are headed for a nice job on the floor. I like how you mention that you will finish it when you take the body off the frame. If only we could do that with the real 151's!

[Nick_]

Wait, you mean I don't have a racing cam?

The spark plugs were pretty dirty. I'll bet that's my issue on a missing cylinder. While I have the head off the engine, it only makes sense to seat the valves and replace all the rubber seals.
My choke wasn't pulled. It has a brand new Airtex fuel pump. Yes I changed the oil after the last ordeal. I'll change the oil and filter before it goes back in the Jeep, now knowing gas isn't draining into the crankcase anymore.
Is there a recommended rebuilder of these carbs and generators? I'd like to get them both checked out.

The floor is pretty neat. I'm trying to incorporate M151 parts on the build, but making them look "stock" to the vehicle. My water fording plate is going to look great on the dash.

[Hambone]

Definitely not running on all 4 and I noticed your choke was open, I would pull all 4 plug wires at the plugs and just let them lay in the plug, get a set of insulated pliers and pull one out at a time, you will find out which one is missing. What kind of pressure do you have on that new fuel pump?, too much pressure will overload the carb causing flooding, might rig up a way to gravity feed a little fuel to it. Remove a quart of oil and replace it with a quart of Marvel Mystery Oil.

[rickf]

It is entirely possible that the carb float is set way to high and that could be why it is flooding. If you have the head off already then yes, you could get the valves done but with the compression you mentioned it might be a waste of money.

[rickf]

Definitely not running on all 4 and I noticed your choke was open, I would pull all 4 plug wires at the plugs and just let them lay in the plug, get a set of insulated pliers and pull one out at a time, you will find out which one is missing. What kind of pressure do you have on that new fuel pump?, too much pressure will overload the carb causing flooding, might rig up a way to gravity feed a little fuel to it. Remove a quart of oil and replace it with a quart of Marvel Mystery Oil.

Getting the generator rebuilt is going to be very expensive if you need to send it anywhere due to the weight. If the bearings are good and make noo noise then it is probably good since they are grossly over built. The brushes are the only other thing that can go bad and you could replace them yourself. If you really want a shop to do it look locally for a rebuilder.

[Nick_]

Definitely not running on all 4 and I noticed your choke was open, I would pull all 4 plug wires at the plugs and just let them lay in the plug, get a set of insulated pliers and pull one out at a time, you will find out which one is missing. What kind of pressure do you have on that new fuel pump?, too much pressure will overload the carb causing flooding, might rig up a way to gravity feed a little fuel to it.

The new fuel pump is an Airtex 60577. I'd try out your suggestions but the engine is out of the vehicle now, but will do so once I get things assembled here in the summer.

Getting the generator rebuilt is going to be very expensive if you need to send it anywhere due to the weight. If the bearings are good and make no noise then it is probably good since they are grossly over built. The brushes are the only other thing that can go bad and you could replace them yourself. If you really want a shop to do it look locally for a rebuilder.

I'm fortunate to live in Amish country where there's tons of little rebuild shops on every road. I have a guy who rebuilds starters/generators for me, but wasn't sure if this unit required anything special. I'll have him at least check it out and the internal regulator.

It is entirely possible that the carb float is set way to high and that could be why it is flooding. If you have the head off already then yes, you could get the valves done but with the compression you mentioned it might be a waste of money.

Knowing my luck I'll build the whole Jeep and need to tear into the valves once I run it. For $35 and a Saturday, I'll go for it. Sent a PM about the carb.

[rickf]

Parts are available for those generators, it has been discussed on here before. I don't remember the name of the company that sell the parts but they are the ones that manufacture the generators.