56 Merc 312 Distributor

56 Mercer

56 Mercer

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I am attempting to bring an old family 56 Mercury Montclair back to life after a long time of sitting in the back of a shop. I have a good blue spark at the plugs, after gapping the points and replacing the ignition system except for the resistor. I prime the carb, and turn it over to get lot of popping and backfire. I assume that I need to time it now, but the issue is I can’t move the distributor. I have found that the retaining clip and bolt are both missing, I know that I need to replace them but shouldn’t the distributor advance and retard anyway?

Any advice would really be appreciated; I don’t have a lot of experience and am trying to learn as I go.
 
As I understand you, there is no distributor hold down and bolt? Is that correct?
If begin to search for those replacements. Shouldn't be that tough to dig up. ebay, salvage yards and forums like this.

Sounds like the distributor is frozen in the block, which does sometimes happen.
Use penetrating oils, mild heat and tapping with something like a soft wood block and a hammer. I heard of some guys using a large pipe wrench in extremes. WARNING! You can break it if you aren't careful! Go careful trying to rotate back and forth little bits at a time. All this before trying to remove it. When it is removed use some 3m cloth or lite sandpaper on the aluminum housing. Your lucky, at least in in pretty close time now!. Mark it on the housing and block before your start trying to move it. Let us know how it goes. Keep them YBlocks Running!

BTW, It doesn't sound like you need to remove it, just get it smoothed up to rotate easier. Kroil, Brake fluid and Acetone mix 50/50, wd-40 stuff like that.

Let us know how it goes?
 
Not to be the harbringer of bad news... but you may have to use a little heat as well. I have seen those distributors locked up solid for years and heat was the only thing that brought them out.

The redeeming factor is that you can get another distributor if you happen to break it. The last one I purchased at autozone was $34.95 after the discount.
 
yes, Y'sGuy that is correct. The bolt hole is there, but no hold down or bolt to hold it. I assume that before me someone else had a problem timing it and removed it.
 
Thanks for the replies and advice. I will start with some penetrating oil this evening. I assume that I should probable remove the piece that the vacuum lines are connected to before tapping on it or heating it.

If it comes down to heating it up it will probable be an over the weekend deal. I did see that on the O'reilly web site there is a remanufactured distributor available. So I guess if it gets too bad, as Hot Rod Reverend noted there is a backup plan
 
just a little info as to why the distributor wont move, there is a rubber O ring on the shaft near the top, over the years it becomes vulcanized to the dist and manifold,, as was stated use a good penetrating oil on the shaft and let set for a few days, keeping the shaft wet, I have used a rubber hammer to tap on the vacuum advance back and forth, and have also use the pipe wrench to turn dist, be patience and go slow, heat may help by melting the rubber O ring, put a crow bar or long pipe under dist to pry up on as you turn the dist
 
Thank you ford3, I am going to start soaking it and hopefully by the weekend it or I will have a different attitude.
 
The replacement distributor may not be the same as the one in your Merc.

In 56 Ford used a vacuum only distributor and has to be pared with the carb. The YBlock replacement distributors I have seen were the 57 mechanical and vacuum type which would not be compatible with the 56 carb. The replacement distributors are getting hard to find because of the lack of rebuildable cores.

You have a Carter carb? As far as I know, the 56 Merc's came with a Carter, not a Holley.

Make sure the wires are in the correct firing order
 
I hate to say it but all the popping and backfiring tends to suggest that you probably have a couple of stuck valves. Take the rocker covers off and check they are all opening and closing. If that is not the problem then it may well be the timing has slipped.
If the engine hasn't run for a long time, the valves do tend to seize.
 
I agree with rick I doubt the dist,has moved in years. someone tried in the past and gave up.look farther.
 
Someone in the past has tried to rotate or remove the distributor for some reason. This may indicate that the distributor has been turned to a point and then the mech just gave up and that the problem is just out of ignition timing. However, if when you check for a stuck valve as rick55 suggested there is not one, and when you get it in time and it still runs bad, you might check to be sure that the timing chain has not jumped timing due to a worn chain or sprockets. This will manifest itself in poping back through the carburetor under acceleration.

The safest thing to do is to remove the intake manifold and soak that distributor with some PB Blaster for several days. Then try to turn the distributor with a pipe wrench; use some heat if you can safely do so. This process may take several days. Keep in mind that the housing is aluminum. As y'sguy said, be careful. Breaking the housing in and of itself is not catasrophic, but then the broken off part is still in the block and you will have to remove the oil pump to drive it out.
 
Wow, a lot of good information came in since I last checked this thread. Both the stuck valve and the timing chain and sprocket do make a lot of sense. Replacing valve cover gaskets is on the to-do list so this might be a good time to knock that out and give the rockers a look. As rick55 did point out this old girl has set for a lot of years. As for the timing chain or sprockets, I am hoping this is not an issue but of course there is no guarantee. I have verified the car has just over 62,000 actual miles on it, I am thinking that the timing chain should go to close to 100,000 in a perfect world. But until I get it up and running, I have no clue as to what it will do under acceleration. Right now a little heat coming from the tail pipe would be great.

The distributor replacement has me a little concerned though. I did understand Hot Rod Reverend got one for $34.95 that was about half the price of one I found online. As paul2748 brought up I do have the Carter carb. So if I do end up needing a replacement what do I need to look for to make sure that I get the vacuum only distributor? Will it show the order of the wires on a new distributor?
 
hang on a sec. on the dist. IMO, I would first do the easy stuff. Check f, from the manual, and RECHECK the spark plug wiring from the dist to plugs. Easy to get it wrong. firing order, etc. No. 1 is on the front pass side. Also check the Dist cap to make sure it is not cracked. Rotor/firing order is COUNTERCLOCKWISE. And the proper pts. gap. If all goes well you don't need a dist. That is depending on what you want to do next - hotrod or stock? Just get it running.
Like has been said about valves. With the valve covers off you can make a quick check to see if the pushrods have jumped off the rockers anywhere. they may be down inside the valley or bent. Not to worry yet. This is from valves being set to loose or stuck.
Keep checking as you go. It can be sorted out.
As far as the timing gear set goes, it is probably worn. And or the Balancer has slipped. Again it can all be sorted out, before you go buying a distributor, just yet.
 
I would still attempt to get the distributor lose so you can set your timing. Use 50/50 acetone/ATF mixture for penetrant. Way better than PB Blaster or any of the other commercial penetrating oils.

Be patient, it will come loose.
 
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ditto form Y-blockhead. If you are going to do anything to this engine to get into running shape you WILL NEED TO HAVE THAT DISTRIBUTOR ROTATE in its bore, I don't care what anyone says. Fact is, the rotation of that distributor is your main timing feature... you need to get that loose first.

Once you do, bring #1 cylinder up to TDC and then make sure your rotor is pointing to #1 on the cap (most caps will have #1 identified). Then secure your distributor to the block with the bolt and hold-down.

The distributors that have vacuum and mechanical advance can be run with an old carb if you plug the carb's vacuum signal port and only run mechanical advance, or if you run manifold advance to your distributor. Also, you can modify the carb itself (there are helpful articles on the internet from engine builder Ted Eaton) to read the proper signal for your distributor.

Whatever you do, never run an old distributor (pre-57) with a 57 or later carburetor.
 
I believe I am with you y’sguy, Y-Blockhead, and Hot Rod Reverend I not running out to buy a distributor. Shoot at this point I don’t even have a hole to stick it in. I am going to keep it soaked in oil and tap tap tapping until I get some movement.

I am going to remove the cap, wires, vacuum lines and housing and resistor to get better access this evening. I will probably pull the valve covers as well.

As far as the wire placement on the cap, point gap the simple stuff that I get excited and overlook, yes they were checked multiple times. They were also reworked a couple times from me getting them wrong, but I feel like I got a great education from it. As especially the part about the plug wire holders bolted to the back side of the block. I know I still have skin from my knuckles hanging back there.
 
I am curious to know if the Y-Block cam gear is nylon coated in original timing sets. I have seen a lot of those go south around the 60-70,000 mile range. Also, even though the distributor is in oil, would the dissimilar metals corrode and become stuck because of that? Would some ant-seize on re-installation be a good idea? I have seen threads recommending heat followed by candle wax as a penetrant as a way of removing stuck distributors, but wonder if that would seal off the distributor if it didn't work, and block other penetrants from making their way past. Good luck on your project.
 
to check to see if the timing chain has stretched, get engine at tdc, put a chalk mark on the crank pulley, turn engine over by hand, watch to see how far crank moves before the distributor rotor moves, put another chalk mark , then by using the timing marks on the crank pulley you can measure the distance between marks to see how far out the timing is because of a stretched timing chain
 
s55mercury66 said:
I am curious to know if the Y-Block cam gear is nylon coated in original timing sets. I have seen a lot of those go south around the 60-70,000 mile range. Also, even though the distributor is in oil, would the dissimilar metals corrode and become stuck because of that? Would some ant-seize on re-installation be a good idea? I have seen threads recommending heat followed by candle wax as a penetrant as a way of removing stuck distributors, but wonder if that would seal off the distributor if it didn't work, and block other penetrants from making their way past. Good luck on your project.
Click to expand...

Questions in order...
Timing gear nylon? No

Dissimilar metals corrode? Yes. FYI, not all Y-Block distributors had a "O" ring as previously stated allowing water to seep in.

Some ant-seize on re-installation be a good idea? Always. Use Anti-sieze or Dielectric grease.

Heat followed by candle wax? I wouldn't :eek:

I had the same problem on my '81 F250. 50/50 acetone/ATF mix, light tapping, patience. It will come lose.
 
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