© 2016 Canada's Capital A's.

TECH TIPS

COMMON CAUSES OF OVERHEATING

 

  • No water in the radiator.

  • Improper timing.

  • Low speed driving.

  • Low on oil.

  • Spark too retarded.

  • Clogged muffler.

  • Too much carbon on the cylinders.

  • Weak exhaust valves (springs).

  • Poor carburetor adjustment.

  • Leaking radiator.

  • Too loose or too tight a fan belt.

  • Round tube radiator.

  • Packing not too tight on water pump.

  • Packing nut too loose and leaking.

  • Air seeping in around manifold.

  • Clogged block and head.

ENGINE OIL SEAL

 

In the last issue of the RADSHELL I spoke about replacement solid steel pulleys. A natural item to compliment that pulley is the one-piece 360deg front seal. It is a direct fit ie no specialty machine work required. It is a major improvement and easy to remember when you say "Mope to Rope". It is a steel body encased in neoprene with the modern type sealing lip and inner retension spring. It was brought to market by a West Coast hobbyist by the name of Terry Burtz. He undertook the project and, we believe, had the manufacturing done be a major seal supplier originally (hint, hint) or maybe still from Chicago. They are available from most major suppliers ie Snyders, Brattons or Mac's, some smaller distributors or from Terry directly in lots of twenty five. This writer has a few left on hand if anyone is interested.

FAN PROBLEMS

 

There are several good articles about problems with the fan but here are some observations. The original 2-blade fan was electric welded sheet steel and sometimes the stress near the hub causes small cracks to form. It is a good idea to inspect the fan blade about two or three times during the driving season to ensure that it is good condition.

 

Cast aluminum fans are now being supplied. These are good but still need to be inspected after assembly to ensure they are tight on the shaft or do not have cracks in the casting. One of these was recently installed and it broke in two when tightened, some fracture marks were seen in the break. This is generally rare. On tour, one driver had a loose fan experience during the Golden Lake trip. It is suspected that the tapers of the fan and the shaft may have been slightly different, so it is important to check the nut tightness of newly installed fans after they have been used for a while.

 

We have seen a problem with broken after market flat bladed fan, after the cast white-metal after market hub became lose and destroyed the key groove. Another case was experienced when a white-metal fan hub broke due to the thin casting. So, regardless of the type of fan you have, check it periodically.

DISTRIBUTOR PROBLEMS

 

Tony's car was showing signs of the recent club malady called Distributor Syndrome or Dave's Blues. After fiddling with the wires in the distributor and changing the condenser, the engine started, so the exact cause was unknown. After some investigation it was observed that the lower plate wire was very long and had signs of being pinched by the lower spring. The wire (A12148W) should be just long enough to clear the pressure spring when the plate is in the full retard (counter-clockwise) position Also the centre electrode of the condenser was turning while trying to remove the screw. This could cause separation of the inner foil from the electrode and result in intermittent operation and should be replaced with A12300SP. The distributor shaft also had some side play, which means the bushings (A12132) should be replaced. This condition will cause the timing and point gap to be erratic. Rotating play in the distributor shaft usually means that the slot at the bottom of the shaft is worn or has become wider. This can be corrected by filing the inner faces of the shaft slot so they are parallel and then carefully squeeze the sides to close the gap slightly.

 

A thin thrust washer (A12188) is required between the shaft ring (the part the cam rests on) and the distributor body to prevent the casting from wearing.

REPAIRING CRACKS IN CAST IRON

 

Stitching a crack in cast iron parts such as the Model A cylinder head, engine block or timing gear cover can be done using the following method. This method has been used for many years.

 

  • Use some 1/8" solid brass rod (as from a hobby store, welding rod has a coating the has to be removed), a 6-32 tap, a 6-32 die and a #36 drill (also from a hobby shop or Legere).

 

  • Centre punch, drill and tap a starting hole at one end of the crack. Cut a thread about 3/8" long on the brass rod and screw the rod end into the threaded hole, seating it hard against the end of the thread. Cut off the rod flush with the surface.

 

  • Centre punch and drill a second hole, using the joint line between the edge of the first plug and the cast iron as the centre punch point. The new hole will cut into the brass and cast iron resulting in the desired overlap. Thread the hole and rod as above and screw in the rod tight. Continue the process until the entire crack is filled with brass. File or grind the brass inserts to match the contour of the rest of the surface.

Rad and Engine Flush

The pictures are worth a 1000 words ! Imagine flushing your rad and engine at 60 gallons a minute with a 1/3 hp sump pump. The rust particles fall to the bottom of the tub and the pump picks up clean water from the top area. This tip was provided with permission from Tom Wesenberg.