37 Flathead Distributor bolt pattern
 

Have to excuse my ignorance as this is all new to me. Bought a 1935 pickup, has a 1937 Flathead in it. Noticed some oil towards the front of the engine compartment, cleaned it up and noticed it look as though it was coming from the distributor flange/housing. I checked the bolts and they all needed tightening.There were only 3 bolts but the distributor housing as a hole for a 4th bolt, lower drivers side. Tried to insert a small rod to see if there was a tap for a bolt and I don't believe there is. So my question is are there 3 bolt and 4 bolt distributors? If so will 3 bolts hold this distributor as designed? Thanks for the help.

Re: 37 Flathead Distributor bolt pattern
 

Re: 37 Flathead Distributor bolt pattern
 

Your distributor only has three bolts. If you still have a leak, you may want to put a new gasket on. Yes, those three bolts will hold it. They’ve been doing it on early diver bell style distributors since the change went to that style after early ‘32.

Re: 37 Flathead Distributor bolt pattern
 

ALSO be advised that IF you go to install a new gasket OR find yours was missing....NOTE.....on the engine/camshaft side of your distributor that there is a key way that fits into the slot on the end of the cam shaft.....NOTE....it is "OFFSET" of the center of the camshaft and can ONLY fit ONE WAY. SO when you go to re-install your distributor, make sure you line that key way up correctly OR it will snap of the distributor side key way. I made some smooth aligning pins (pictured) for this operation BUT IF you have a couple of longer 5/16 bolts ITS a heck of a lot easier to install two longer bolts into the opposing bolt holes and use them to slide your distributor back up to the motor. I use my two thumb in and on the rotor of the distributor to turn the shaft as I gently put pressure against the cam face until I feel and sometimes here the key way line up and drop into place. THEN you can install the third bolt to hold the distributor in place THEN replace each of the longer alignment bolts one at a time with the proper mounting bolts.
Also, when you re-install the distributor caps, NOTE those have square notches in the caps that fit into the corresponding opening on the distributor SO sort of give them a gentle twist back and forth to make sure those seat properly into place. IF you have your distributor off it helps to clean the distributor cap openings with some fine scotch-brite pads or some fine sandpaper as sometimes they get a little dirty and tight. make sure you cover the inside with a shop rag to keep the points and all clean and blow it out with air as well before you re-install it!!!!

Re: 37 Flathead Distributor bolt pattern
 

Thanks for help. I can see how the aligning pins will be a great help.

Re: 37 Flathead Distributor bolt pattern
 

Re: 37 Flathead Distributor bolt pattern
 

AB1935, also note that the 4th hole in your '37 distributors cast flange on the housing, was provided by FOMOCO when that same distributor is used in another application that does not apply to your 85 hp engine.

Re: 37 Flathead Distributor bolt pattern
 

John, a sign of getting old... I've been waiting for someone to name that application because that detail has slipped my mind!