There is a small crack in the pump housing and it has created a pinhole size leak. Is there a way to fix this, or do I need to replace the housing?

front seal, leaking oil means there is less oil in engine. continue and you will a new engine, have it repaired quickly.

If you are talking about the evaporator for the ac, the component would need to be replaced.

see this causes and fix it. God bless you
Water pump -- A bad shaft seal will allow coolant to dribble out of the vent hole just under the water pump pulley shaft. If the water pump is a two-piece unit with a backing plate, the gasket between the housing and back cover may be leaking. The gasket or o-ring that seals the pump to the engine front cover on cover-mounted water pumps can also leak coolant. Look for stains, discoloration or liquid coolant on the outside of the water pump or engine.
Radiator -- Radiators can develop leaks around upper or loser hose connections as a result of vibration. The seams where the core is mated to the end tanks is another place where leaks frequently develop, especially on aluminum radiators with plastic end tanks. On copper/brass radiators, leaks typically occur where the cooling tubes in the core are connected or soldered to the core headers. The core itself is also vulnerable to stone damage. Internal corrosion caused by old coolant that has never been changed can also eat through the metal in the radiator, causing it to leak.
Most cooling systems today are designed to operate at 8 to 14 psi. If the radiator can't hold pressure, your engine will overheat and lose coolant.
Hoses -- Cracks, pinholes or splits in a radiator hose or heater hose will leak coolant. A hose leak will usually send a stream of hot coolant spraying out of the hose. A corroded hose connection or a loose or damaged hose clamp may also allow coolant to leak from the end of a hose. Sometimes the leak may only occur once the hose gets hot and the pinhole or crack opens up.

PUMP HOUSING LEAKS.. 3 THINGS COME TO MIND.# 1 IS THE SHAFT SEAL #2 IS THE TANK GASKET IS BAD, OR THE DREADED TANK BODY IS CRACKED. NOT UNCOMMON FOR THESE PUMPS. TAKE PUMP APART (MOTOR OFF) LET SIT AND DRY A LITTLE AND YOU WILL NEED TO LOOK CLOSE AND THE CRACKS STICK OUT BETTER WHEN SLIGHTLY DRY. IF IT IS CRACKED, THERE IS NO FIXING IT WITH GLUE. IT MUST BE REPLACED. IF IT COMES TO THAT POINT , I WOULD RECOMMEND A STA RITE DURA GLASS . 1 HP. THE SUPER PUMP YOU HAVE IS NOT THAT EFFICIENT. THEREFORE I RECOMMEND THE SR 1 HP. IT WILL SAVE YOU ON POWER ALSO , HEY YOU .. REMEMBER TO PRIME THE PUMP AFTER ANY PUMP REPAIR !!!... JAY FLORIDA

check the radiator hose going to thermostat housing.it could be leaking.if hose okay.thermostat seal more likely leaking, meaning you have to replace the thermostat with seal.if thermostat with new seal still leaking.thermostat housing has a small crack in it.need replacing.

One or more of a couple issues is at play here. First would be the seal replacement. Even if you used the correct seal if you touched the surfaces or failed to install it properly it can and will leak. Second, inspect the housing around the seal fit and the stem of the impeller for cracks. A hairline crack is enough when placed under pump operating pressure to allow a leak. Somewhere in there is your solution.

John

CHECK FOR LEAKING WATER PUMP WEEP HOLE OR GASKET.ALSO CHECK WATER PUMP HOSE FOR LEAKS.IF ALL LOOKS GOOD.YOU COULD HAVE PINHOLE LEAKS IN RADIATOR CORE LEAKING ON FRONT OF ENGINE OR INTAKE MANIFOLD GASKET LEAKING COOLANT.

My roof is the same way ... only leaks when it is raining. Can't fix it in the rain and can't find it in the sun.

For best results, replace the pump. You may find the parts from the manufacturer. As you replace the part, you will discover there is stuff inside that will not only revolt you, it will make replacing the cracked casting more difficult.

If it is a small crack, you might be able to patch it with a procuct called MarineTex available at Ace Hardware, or other fine store in your area. If you live in an area where boating is a big past time, look at the Marina for this product.

Oh, BTW, I might have called it the wrong name, it is a two part exply boat repair kit product. Expect to pay $20.00 for a small supply.

Thanks for your interest in FixYa.com

I had the same problem and could not exactly pin point the leak until I took a real close look at the pump when everything was dry. I could see that the small weep hole was leaking which meant that the pump had to be replaced.
ruling out that there is a crack in the pump itself, it is more than likely to be a hose or its connection to the pump, the pump seal to the engine block or the weep hole on the bottom of the pump housing.

If you are to change out the pump yourself, you need remove several parts off the front of the engine so if you are not too confident, I would suggest paying someone to do the job.

Hope this helps