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Stumped - Low power

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Andy45cal View Drop Down
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    Posted: 15 May 2019 at 7:29pm
Just got my CJ2A back from getting the engine rebuilt. Sluggish on the 15 mile trip home - top speed around 40. Went to come up my hill and I ended up in first going about 8 mph! Seems a little cold blooded to start out. The plug on the floor board where the gas pedal rod goes thru is gone, the foot feed wants to cant to the right, does not have the power it should! It also has been at the mechanic's shop for 14 months, could the gas be bad? Condenser? Fuel pump? Have stuck a lot of time and cash into her and I'm getting frustrated!! Ideas?
Thanks ahead of time!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote berettajeep Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 7:38pm
My first thought is to take it back if it is not right after being rebuilt.
I'm not sure what you mean by plug on the floor.
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Mark W. View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Mark W. Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 7:45pm
Make sure the carb is opening all the way and that the throttle linkage is free and operating properly. And if your gas has been in the tank for 14 months its crap. if you can get to and open the drain I would drain the tank and refill.
Chug A Lug
1948 2A Body Customized
1949 3A W/S
1957 CJ5 Frame Modified
Late 50's 134L 9.25"clutch T90A D18 (1.25") D44/30 flanged E-Locker D25 5.38 Since 1962
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Andy45cal View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Andy45cal Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 7:49pm
The "plug" I'm sure is an improper term. When your right foot pushes on the gas there is a rod that goes thru the floorboard - where it goes thru is a hole maybe 1" or so in dia. That is where I need a "plug" grommet or something. At present there is just the hole there.
Thanks again!
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Andy45cal View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Andy45cal Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 7:50pm
Will do! Thanks! Drain the tank and check the linkage!Smile
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Post Options Post Options   Thanks (1) Thanks(1)   Quote russnj Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 8:08pm
What Mark said! Thumbs Up

43 MB, 48 CJ2A, 50 CJ3A, 56 CJ5, 79 M151A2, M100 ,65 M416
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Post Options Post Options   Thanks (0) Thanks(0)   Quote athawk11 Quote  Post ReplyReply Direct Link To This Post Posted: 15 May 2019 at 11:19pm
The boot down below the pedal was originally made of leather.  Later they were rubber.  Most of the time, this boot is long gone.  It will have little to no effect on The stability of the linkage.  Based on the design of this portion of the linkage, it will generally have some lateral movement.
1- 1946 CJ2A   
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Post Options Post Options   Thanks (1) Thanks(1)   Quote 1947-cj2a Quote  Post ReplyReply Direct Link To This Post Posted: 16 May 2019 at 9:21am
Sounds like mine when I flipped two of the spark plug wires. It started, it ran, but when I pressed on the
gas it didn't have any power. Because it ran correct before I replace my plugs, I Started checking there
and found my wires flipped.
RICH

1947 cj2a (Toy From Hell)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nobodyjeff5888 Quote  Post ReplyReply Direct Link To This Post Posted: 13 June 2019 at 2:06am
the throttle linkage on the back of the motor has a small cotter pin that hold it in place. Mine rotted off and caused extra slop in the linkage. Hard to ge to but might be your problem
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Joe DeYoung Quote  Post ReplyReply Direct Link To This Post Posted: 13 June 2019 at 8:27am
Andy, any progress on a solution for low power? If not, I would check valve stem to tappet clearance. 
Joe DeYoung
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Rus Curtis Quote  Post ReplyReply Direct Link To This Post Posted: 13 June 2019 at 9:44am
Back in the late '70's I had this issue when picking up from a shop shortly after purchase.  Could not top 35-40 mph.  Another much smarter mechanic identified the problem as worn bearings in the distributor - affecting the points.
 
What he showed me was the slop in the shaft wiggling back and forth.  In addition to everything else being offered, you could eliminate this as a potential problem.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote drm101 Quote  Post ReplyReply Direct Link To This Post Posted: 13 June 2019 at 10:05am
Check that when you put your foot to the floor, that the throttle is all the way open. 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Greaser007 Quote  Post ReplyReply Direct Link To This Post Posted: 16 June 2019 at 11:21am
Andy,
   Don't take that 45 cal to the engine quite yet !   hahaha

I was snooping around this morning and happened to read this. My First thought was that your Ignition-Timing is Retarded too far.
    Now, this may have been a planned ploy by your engine builder to keep you from Hot-Rodding that engine right out of the Chute !

    Make a mark on Dist base and block to preserve where your starting point is, and then advance the Distributor by about 1/8-inch and take it for a run !
    I was taught decades ago to keep advancing the timing until the engine Pings under heavy acceleration. Then back off (retard) the timing until No-Ping.

    I always have to chuckle when tight engine tolerances are adhered to, because if running an engine hard, the result is heat generated, very similar to a lean air-fuel ratio.   Lean mix = Heat generated. Lean mix means go faster for race day, and if pushing to the limit, if too lean, you will burn a hole right through the top of the piston.   (who got your pink-slip) ?

An example: Forged pistons vs cast pistons. Forged pistons expand much more than a cast piston. therefore - if the forged piston expands .003 from cold to running temps, and the preferred operating clearances are .002 piston to cylinder wall, that means you must have a cold clearance of .005 !
OMG, the Factory Service manual says clearance to be .002 cold, but if we just added forged pistons to the engine build, then .002 won't work very well. Hmm.
These little flat-head engines don't really wind tight enough to warrant Forged pistons. We tend to forget that marine engines in an inboard jet boat typically are run at 4,500 rpms up on Plane, and may be run at this rpm or higher for a sustained 12-miles across the lake. Versus the little Willys lugging along the trail at 600 rpms and it seems to me that this is barely enough rpms to make the pistons "squirter" hole to function properly or should the engine be running at 1200 rpms for the "squirters" and oil "splash" to properly lubricate the engine internals. Just thoughts _ _ _ :)
Heaven Forbid if a rebuilt engine should have .005 piston to wall clearance, because the "Book" says clearance to be .002 or maybe less.
So, then, let's say your engine builder set up your piston to wall @ .002, and for whatever your pistons are, they expand .002, then your engine will not be running Free, and may be very sluggish, and may even Score a piston or pistons.
   Most folks take an engine to a rebuilder, and don't discuss the fine points of what they want for clearances, and leave them up to the builder. Hmm !
   Then you pick up your engine, and what do you have ? - the builder's choice.    Go to a shop that builds race engines like marine engines that are run at high rpms, and discuss options.
    I am just rambling.

    As mentioned above, check your throttle linkage to make sure your carb throttle plates are opening fully with gas-pedal pushed to the floor.

Here is an example: my brother-in-law took his L134 to an engine builder and paid $2,600 smackers for a "rebuilt" engine. After my BIL installed the engine, I asked him what did the builder do to your engine ?   His response was "I don't know."   Did they re-use the old pistons, and bearings and just do a valve seat grinding and a cylinder de-glazing ? Who knows, _ _ he didn't.
But he shelled out $2600. (I sent him to this 'builder' because they specialize in race engines and are a very reputable shop). I trust them.

    We don't know what the engine builder did with your carburetor if anything.

    One thing is for-sure !   it is nice to know you have a rebuilt engine.
    
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