I just got my 351w done. New rings, rod Main and cam bearings, Cam, lifters, and Intake. Everything looks good so far.

The problem is that the Distributor wont go in. Seems like it is not fitting the Cam gear properly. What could be the problem? This is with two separate 351w distributors.

Thanks for any help.

 

Get a priming tool, and spin the oil pump driveshaft several times, and try again. You may need several attempts, but it will eventually seat itself on the driveshaft. You can also spin the engine, but that makes setting your timing much more difficult. TK

 

Thanks TorqueKing. One question though. How would spinning the engine over work? I could be wrong but, if the distributor isn't going all the way down then isnt there a chance of tearing teeth on one of the gears if not both? Just wanted to check before trying anything.

Basically you can feel the bottom of the teeth on the distributor start to slide in, then it locks up tight. Will not go any further.

I will try a priming tool. As far as timing the thing, I can get that if I can just get the distibutor in.

Thanks again.

 

because if you turn the engine, the cam drive teeth will move as well, and allow the gears to mesh in a different position. I don't recommend that though, because the oil pump driveshaft is so easy to move.

 

Ok, sorry about that. I wasn't thinking about the cam gear. But, yeah your right. I will give this a try in the morning. Thanks again.

 

The distributor is a pain to install due to the hex design of the oil pump drive. So the headache you are experienceing is common, it is usually recommended you prime the oil pump until you see oil start flowing from the heads, good luck.

What kinda setup you have?

 

It may seem hard to believe but distributors for the 351W have two different shaft lengths. Carbed engines use a distibutor with a shaft that is a lot shorter than EFI engines. The EFI distributors have the same length shaft as a Mustang 5.0 distributor, but are built to fit the larger diameter oil pump drive in the 351.

If you use a 351W distributor with a longer shaft the bottom of the shaft can bottom out on the oil pump driveshaft retainer ring, or the non-hex portion of a hardened oil pump drive shaft. This will prevent the distributor from seating correctly on the block at the top. In this case, the solution is to grind about 1/4" off the end of the distributor shaft. I know it sounds crazy, but I had this exact problem and after the grinding the shaft down it seated fine and has been running fine, even with over 6000 RPM on the drag strip.

How do you know which distributor you have? The short shaft version has a shaft length of about 3.5" measured from the bottom of the distributor housing to the end of the shaft. The longer shaft version measures about 4 1/8" using the same reference.

Another possible issue, and one that is apparantly pretty common with 351W setups is that there could be a clearance problem between the bottom of the distributor gear and the block. You need to check this clearance with a feeler gauge with the front cover off. When the engine is running, the cam will tend to pull the distributor gear downward and reduce the clearance if there is any end play in the distributor shaft. When this happens, you will typically break the roll pin holding the distributor gear on the shaft. In some cases this problem could also prevent the distributor from seating correctly.

I hope this helps you out.

-Matthew

 

Thank you all for the replies. I will check the length of the shaft on the distributor. The old distributor I tried first came out of a 74 model 351w with a carb of coarse. It is going into a 71 model carbed 351.

I'm not sure what you mean exactly about what my setup is. So here is what I did to the engine. I pulled it out and tore it completely down. Honed the piston walls, checked the piston good and they were in excellant shape (flat top pistons), put new rings on them, New cam and rod and main bearings, Edelbrock Performer Intake and Cam.

I didn't prime the pump until oil was coming out of the heads. Will do that though, Makes sense. 5/16 nut driver works great for this.

When I pull the front cover off I will check the clearance between the gear and the block also.

 

tracman
thats what I wanted to know. When you get it running let us know how the performer cam does. I did a little looking and the pump drive in question for the 351's are all the same only the 302's vary in length. What your experiencing is probably normal given the distributor is okay, I have always had a little trouble installing the ford distributors, just turn the pump drive a little at a time until the distributor drops. Good luck let us know how it goes, later

 

The oil pump drive shaft length doesn't vary on 351W's, but as I said earlier, the length of the distributor shaft does. An EFI truck distributor like the E4TE-12131-CA has a longer shaft than a carb truck distributor like the D0AF-12131-A. What's more, the stock 5/16" hex driveshaft for the oil pump is a hex shaft throughout its entire length, but if you use a hardened replacement like the M-6605-A341 from Ford Racing, only the ends of the shaft are hex, while the rest is a round shaft. This prevents the longer distributor from dropping down all the way.

I personally experienced this problem with a 351W conversion in a Mustang that I did. Using an EFI truck distributor with the longer shaft, the distributor would not seat, and instead sat about 1/8" up off the block surface at the top. I went and pulled distributors from various wrecks to compare them, and verified the problem, plus I also found a number of other people who ran into the same problem with their 351W swaps in Mustangs, a job that typically involves a hardened oil pump drive shaft.

I'm not saying that this is for sure tracman's problem, but it's a real problem and one that you would not normally consider.

Just as an aside, when you are spinning the oil pump drive with your 5/16" nut driver on a reversible drill, do yourself a favor and tape the whole thing together with electrical tape so that you don't accidentally drop the socket into the oil pan. I know that some people suggest doing this with the valve covers off to verify oil at the heads, but it's probably ok to just watch for oil pressure and then give it 20 seconds of pumping after you see oil pressure. This method is certainly cleaner, and allows you to go straight to startup after priming with the least amount of delay.

-Matthew

 

Gotchya I was thinking oil pump drive shaft and you where saying oil pump shaft. We are on the same page I was just thinking something other than what I was reading. I didn't even consider that as he seemed to be leaning toward the fact he was reinstalling pieces that were originally in the motor (why I asked what has been replaced). Good point, later

 

Well the only thing that was replaced that would actually make a difference on that part is the Cam. Thats what is throwing me off. The block Oil pump shaft, etc are all the same. The two distributors matched up the same. The old one wouldn't go in, so I decided to use it for the core charge on a new one.

I'm not sure if it is bottoming out or not, but will check into that. Will be Monday before I get the chance to tear it all apart. Its at my Uncles house which is a bit to far to drive for a couple hours work...

Anyways, I will definately let you all know what I find. (I'm tempted to just put my Old Cam back in it, I know it was a good one.)

 

Not to keep saying this but I returned two distributors thinking something was wrong when it was just a pain to line up the cam and oil pump drive with the distributor, good luck hope it works out

 

I’m curious what ended up being the problem? I am having same issues with my Windsor build.

Anthony

 

Usually it's because oil pump drive shaft won't line up with the hole in the distributor shaft as its gear is meshing with the cam gear. I usually use a socket on a long extension to turn the oil pump shaft a little and try installing again.