Water Pump Housing Spewing Oil Outside

[rbruce63]

My Chrysler 20 HP model 2003 circa 1969 water pump housing spews dark oil on the outside. This is definitively oil from the combusion process as it comes from way above the upper vent screw of the lower unit oil. Could changing the driveshaft o-ring resolve this problem?<br /><br />I speculate that the worst case scenario is that the lower main seal of the crankcase is the culprit. Please advise on the gravity of the problem and if it could be ignored.<br /><br />Otherwise, this seemingly old motor has 50 hours on it and I would hate to damage it.

 

[eurolarva]

Re: Water Pump Housing Spewing Oil Outside

Are you talking about the two small holes on the starboard side on the lower unit? This is the exhaust port for your motor. You are going to see some discharge from gas and oil there. I am curious to see some responses on how to minimize this. I am seeing it as well with my 67 chrysler 45Hp.

 

[scotiany]

Re: Water Pump Housing Spewing Oil Outside

Other than spewing oil , how does it run? Does it stop spewing at planing speeds. Do you have a thermostat installed? If not, you could have incomplete combustion.

 

[Drowned Rat]

Re: Water Pump Housing Spewing Oil Outside

Hi, rbruce63. Are you getting water in your lower unit? If the oil you are seeing is coming from the L/U, the only way it can get there is around the drive shaft seal or the shift linkage seal. It could also be what scotiany suggested. If you don't have water in your L/U, he's probably right. Does the oil come out the below water exhaust too?

This is definitively oil from the combusion process as it comes from way above the upper vent screw of the lower unit oil

It could still be L/U oil. If your drive shaft seal is bad, you will be pumping L/U oil through the engine and out the exhaust. Try pulling the L/U and take a look. It should be apparent if that is the problem.<br /><br /> Good luck, let us know when you figure it out.

 

[eurolarva]

Re: Water Pump Housing Spewing Oil Outside

An easier way to find out if your lower unit is leaking is pull the drain plug and see what color oil is coming out. If water or milky white oil comes out it is a leak in your lower unit. However what you are describing is exhaust gases and oils. You are probably buring too rich. The manual gives a procedure to adjust idle mixture screw. It is better to burn slightly richer then too lean.

 

[rbruce63]

Re: Water Pump Housing Spewing Oil Outside

Eurolarva, Scotiani and DrownedRat: <br /><br />Yes, it is also spewing oil from the two drainage holes on the lower leg portion. I will check the lower unit oil condition also. <br /><br />This oil spewing occured after my "mechanic" tore down the lower unit to replace the 10 blade impeller as one of the blades almost came appart. I feel he was not as careful as I was before, but the motor had overheated on the last leg of a 200 mile rally and I was very upset and have had the motor's head resurfaced. I even speculated that this "mechanic" forgot to put the driveshaft seal and that this was the culprit.<br /><br />But I think the blame is on running the motor on "earmuffs" instead than warming up in a lake. As the it only runs for 5 mintues and only at high idle, the oil ratio is probably on the excessive side of 50:1. I will also check the condition of No. 2 Spark Plug to check for lean running condition in case I have to replace the lower main seal.<br /><br />I will do all the check ups that you recommend this weekend!

 

[eurolarva]

Re: Water Pump Housing Spewing Oil Outside

No need to remove lower unit. If water is coming out the telltale with muffs on your impeller is working. Just remove the drain plug and let a few drops of lower unit oil come out. If there is no drive shaft seal or a leak at the drive shaft the oil will be white and or water will come out fast. <br /><br />You might want to order a thermostat and a gasket to verify you have a thermostat in your motor. When you take the housing off you will ruin the gasket

 

[rbruce63]

Re: Water Pump Housing Spewing Oil Outside

Scotiany:<br /><br />There were no thermostats in Model 2003 Chrysler 20's. And the funny thing is that when you start the motor in a tank at the first start it throws quite a bit of water from the idle relief port after a while my baby boy spews more water than this motor's pee hole!<br /><br />I imagine that the flow of water is not regulated except for the rpms of the shaft that controls the impeller, but there was no thermostat to keep the temperature in check.<br /><br />In later models for instance 1981 the last year for the 20HP they came with a thermostat in the head.

 

[scotiany]

Re: Water Pump Housing Spewing Oil Outside

rbruce63, noted , interesting that it doesn't have a thermostat.

 

[rbruce63]

Re: Water Pump Housing Spewing Oil Outside

Scotiany, <br /><br />I would rather say about the lacking thermostat: odd. The higher HP motors of the same vintage had a thermosat, even those designed by West Bend. Perhaps it was oriented as a motor not to be used strenously. But this is only speculation. There is probably no one that designed these motors around.<br /><br />I took the spark plugs off today and did not notice much difference. The top plug was a bit more oily than the bottom one, but I would not know if the bottom one was drier due to the lower crankshaft seal leaking oil.<br /><br />Is there a way to check if the lower crankshaft seal is leaking other than removing the short block?

 

[scotiany]

Re: Water Pump Housing Spewing Oil Outside

Just a shot in the dark. Have you rebuilt the fuel system? Could the innards of the carb be clogged? Have you ever replaced the fuel pump diaphragm? Another thing , I had trouble with my lower plug always fouling and unburnt oil spewing out. It turned out to be a clogged "puddle valve" . It's basically like a PCV valve on a car. I can't tell you where it is on your engine or even if you have one but, I suspect that you do. Not too hard to remove and clean. BTW Chryslers of that era could have the fuel components cleaned with gas according to their manual.

 

[rbruce63]

Re: Water Pump Housing Spewing Oil Outside

Scotiany;<br /><br />This puddle plug is what Chrysler called in his brochures the oil recirculation valve. This came as a response in 1978 to environmental concerns and probably good industrial practices at Chrysler Marine. It is common in higher horsepower motors. You can read about this at www.hurrikain.com/thechryslercrew/78-ob.htm<br /><br />I rebuilt the fuel system and the carburettor was cleaned but not rebuilt in September last year. Anyway I do not have the savvy to repair carburettors myself and had this comissioned to a salted mechanic. I hope he did this well but I believe my Chrysler motor is the last of a breed.<br /><br />Thanks for all the input.

 

[rbruce63]

Re: Water Pump Housing Spewing Oil Outside

Scotiany:<br /><br />The correct link in Hurrikain's web site that has a picture of the oil recirculatin system is the following: http://www.geocities.com/thechryslercrew/ <br /><br />However, the purpose of the oil recirculating system is to provide for a way of getting rid of puddled oil in the crankcase. This occurs when trolling.<br /><br />I will try to get to the water this Sunday and hope that the motor, carburetor and all the other systems are fine.<br /><br />Wish me luck!