Distributor Stuck - 233CI

Just joined. Working on my brother's 1948 KB5 box truck. Am doing a 6Volt pos ground to 12Volt negative change over, keeping the original looks of everything.

Truck has 42,000 and been sitting. Runs, but needs work to include a tune-up. The distributor has the vacuum advance system which rotates the distributor within the block as opposed to the late and more common distributor which rotates the points plate.

The distributor is stuck, will not budge. I did buy another distributor as a back-up just in case I damage the one I have in trying to get it out. Put Marvel Mystery oil on it at the base several times. Purchased a strap style pipe wrench thinking I could wrap it around the housing and use the leverage of the handle to break it loose. Not a lot of room, so this is not going to well. Next I used my air hammer and a flat round die which is designed for "pounding/shaping" much like a body hammer and tapped around the base of the distributor housing - not enough or so violent as to damage the housing.

Not a lot of room to go in with a torch/heat and apply that to the block - which makes me nervous as I do not want to crack the block from excess heat applied to one place. Thought about gutting the distributor and putting some dry ice down the housing as I have heard this can sometimes contract/draw-up the metal and thus break it loose.

I read that a 50/50 mix of Acetone and ATF is a real good solvent to free up stuck parts - so that will be next. However, looking at it so as not to break anything and to get to the distributor better, I though an option may be to pull the fender for access and then I might be able to strong arm the thing, but that will be a last resort as no doubt that could become a challenge in itself.

Been working on old & new cars for 40 plus years as a hobby and have all the tools and skills to get the job done, just never worked on a vehicle this old or ever had a distributor stuck in the block.

That said......any suggestions that may work that I have not thought of or tried?

curious if you loosened both the hold bolts, there is one that holds a flat plate under distributor down and a pinch bolt that squeezes the distributor shaft,

the squeeze bolt is sometimes hidden behind the distributor covered in goo

pictures help

curious if you loosened both the hold bolts, there is one that holds a flat plate under distributor down and a pinch bolt that squeezes the distributor shaft,

the squeeze bolt is sometimes hidden behind the distributor covered in goo

pictures help

Thanks for the reply. I only removed the "hold bolt". I know exactly what you are talking about as the "pinch bolt." I have not loosened it, but yes, it is on the back side of the distributor and is accessible.

However, looking at my "spare" distributor, the pinch bolt appears to only hold the bracket which clamps around the base of the distributor to which the vacuum advance arm pulls on in order to move the distributor housing (advance/retard) within the block. I did move this bracket on the distributor on my engine thinking it might move the distributor, but it did not move the distributor, it simply rotated on the base.

So it appears the "pinch bolt" is what locks the top plate onto the base of the distributor which in turn rotates the distributor within the block (to adjust engine timing) as it gets pulled by the vacuum canister arm. The hold down bolt passes through an elongated hole in the plate so the distributor can move back and forth. Next is a center plate, the timing indicator or "pointer." It has a single bolt hole and the hold down bolt goes through it. It has no movement and is what holds the distributor to the block. Finally, a third plate on the bottom is the bracket which the vacuum advance canister is bolted to, has an elongated hole like the top plate, and has the hold down bolt go through it. This plate has the Advance/Retard timing graduations stamped on it to which the "pointer" indicates the distributor's timing - advanced or retarded. I assume this is done once the timing mark at the balancer/pulley on the front of the engine has been lined up to indicate No.1 cylinder firing. Instead of having the timing marks on the balancer and timing the engine with a timing light like most cars do, the timing is done at the distributor by turning the distributor which then moves the "pointer" and uses the timing marks found on the bottom plate mounted on the distributor.


All 3 plates form a "sandwich" and it appears that when you tighten the hold down bolt, it will lock down the middle and bottom plates which holds the distributor in the block, but the distributor base is still able to rotate freely within these two bottom plates as they are a slip fit. The top plate with its pinch bolt is clamped to the distributor base and is what rotates the distributor to adjust the engine timing through the pulling action of the vacuum advance can/arm.

That all said, it would appear that the distributor is held down by the "hold down" bolt and the "pinch bolt" holds the top plate used for vacuum advance. BUT, I am no expert on these engines by any means and if you think I should loosen up the "pinch bolt", it is easy enough for me to get at and I can certainly give it a try.

If you need a picture of the spare distributor, I can take a couple pics and post them so you can see the plates found at the base of the housing.

Thanks.

I'm very familiar with these distributors, your lengthy answer is a bit confusing as to whether your distributor is in fact frozen in place or distributor body rotates but won't pull out of the block, if it rotates it will remove,

if it is frozen in place and won't rotate with vacuum advance then you need some penetrating oil or something like you mentioned,

eliminate the easy answers first is my motto,

It's a bit complicated and here is a thread with a many pictures and a lot of back and forth on how it works. I think you are missing the special tapered spring?

http://oldihc.org/phpBB3/viewtopic.php?f=7&t=7167&hilit=distributor

One suggestion as I had to fight with this until I finally gave in is to remove both inner fender wells. The ones with the big louvers in them. Then you can lift the truck and go in thru the drivers side after taking the front wheel off. Just so much better access. Remember that IHC actually built the K/KB trucks so you can easily remove the entire front fenders/grill assembly to work on the motor! Pictures have been posted of this and it's even in the shop manual which by the way I HOPE you have?

Here is how much better access you have to the engine compartment with the inner fender wells removed.



The inner fender wells have a lot of bolts and they will be rusted. I got everything removed but had to use heat on about 1/2 of the bolts and burned some paint on the drivers fender.
My fault and I think if I had been paying attention better a wet rag might have prevented most if not all the damage.


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I'm very familiar with these distributors, your lengthy answer is a bit confusing as to whether your distributor is in fact frozen in place or distributor body rotates but won't pull out of the block, if it rotates it will remove,

if it is frozen in place and won't rotate with vacuum advance then you need some penetrating oil or something like you mentioned,

eliminate the easy answers first is my motto,

Sorry to be confusing, but I wanted to explain what I believed the "pinch bolt" held - which was not the distributor. So the answer in a nutshell is "yes," my distributor is frozen/stuck and will not move - "hold down" bolt is removed..

the hold down bolt holds the advance mechanism to motor, the pinch bolt holds the distributor to the advance mechanism, if yours won't rotate at all, then I'd try a big pipe wrench and penetrating oil,

I wonder if you could use a oil filter wrench after removing the electrical contact post and cap clips thru the side to avoid marring it with pipe wrench?

what you want to do is try to rotate/wiggle it even if just a little bit back and forth while soaking the block where it enters, trying to just pull it straight out will be futile,

back and forth rotation should get you a little more movement as you do it, until it is free enough to try pulling up while twisting,

good luck, we had a rotor shaft frozen into the distributor once, took a lot of penetrating oil and rotation (attemps) until it finally freed up,

It's a bit complicated and here is a thread with a many pictures and a lot of back and forth on how it works. I think you are missing the special tapered spring?

http://oldihc.org/phpBB3/viewtopic.php?f=7&t=7167&hilit=distributor

One suggestion as I had to fight with this until I finally gave in is to remove both inner fender wells. The ones with the big louvers in them. Then you can lift the truck and go in thru the drivers side after taking the front wheel off. Just so much better access. Remember that IHC actually built the K/KB trucks so you can easily remove the entire front fenders/grill assembly to work on the motor! Pictures have been posted of this and it's even in the shop manual which by the way I HOPE you have?

Here is how much better access you have to the engine compartment with the inner fender wells removed.



The inner fender wells have a lot of bolts and they will be rusted. I got everything removed but had to use heat on about 1/2 of the bolts and burned some paint on the drivers fender.
My fault and I think if I had been paying attention better a wet rag might have prevented most if not all the damage.


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Thanks for the great pics, yep it looks similar to my KB5. I realize there will be much more room to get at and work on the distributor side of the engine. I may have to do this as you did. I did not realize I could leave the fender on and just pull the inner fender. All the bolts are rough looking as you found out, I know I will be using heat to hopefully get some loose and probably wind up torching or using the die grinder to get the stubborn ones off. No problem in doing this, but prefer not to remove the inner fender if I can avoid it. I figured I would have to remove the tire/rim and that's where I may get into trouble as I don't have an air impact wrench or impact sockets to fit the lug nuts. However, I do work in a tractor-trailer shop and can probably borrow the tools if it comes down to it.

Yes, I am indeed missing the "tapered spring." The truck has been played around with and many things were not done or repaired as they should have. Probably someone just trying to keep the truck running over the years, but really not putting a big effort into it to get things right. I will have to come up with the "tapered spring." Almost looks like I might be able to use a tapered spring from a brake parts kit. LOL

I do have the reproduction " "K" and "KB" Service Manual 19401/2-1949." Also have the Zenith carb rebuild/adjustment pamphlet and have already rebuilt the carb.

the hold down bolt holds the advance mechanism to motor, the pinch bolt holds the distributor to the advance mechanism, if yours won't rotate at all, then I'd try a big pipe wrench and penetrating oil,

I wonder if you could use a oil filter wrench after removing the electrical contact post and cap clips thru the side to avoid marring it with pipe wrench?

what you want to do is try to rotate/wiggle it even if just a little bit back and forth while soaking the block where it enters, trying to just pull it straight out will be futile,

back and forth rotation should get you a little more movement as you do it, until it is free enough to try pulling up while twisting,

good luck, we had a rotor shaft frozen into the distributor once, took a lot of penetrating oil and rotation (attemps) until it finally freed up,

Yep, I have a strap style pipe wrench that is much like an oil filter wrench, but bigger. The arm is too long and strikes the inner fender well so I can't really get the good leverage out of it I would like. If I take off the inner fender well, then I would have no problem in strong arming the wrench. My guess is that I will have to bite the bullet and take that inner fender well off which probably would not be a bad idea as I have all the tools, could replace the old bolts with new, which would make this much easier should my brother or his mechanic up in Rhode Island need to pull the inner fender well for whatever reason.

I could transplant a V8 and automatic into the truck and my brother has inquired about me doing this, but I feel that the truck is in too good a shape and original that he let me see what I can do to keep it original. I have no problem "hot rodding" an older vehicle IF it is in poor shape and the drive train is bad or missing and your purpose is to save the car/truck from the scrap heap. This truck is too nice and original and I told him we need to try and keep it this way - he listens to me. LOL

the inner fenders sometimes come right off, other times not so much,

good news is the "nuts" are welded to the fender so you don't have to have one hand inside engine bay the other under wheel well,

bad news is the "nuts" are welded to the fender so if one breaks free of the weld it is a round nut with a flat spot and they spin so you have to have one hand in the engine compartment and the other under the wheel well,