Speed Seal Installation

[Mike Vaccaro]

We recently installed a speed seal kit on our raw water pump (Oberdorfer).  The pump cavitated during shakedown and lost it's prime, resulting in an overheat.  We didn't have any problems with stock cover/gasket combination.  This mod was performed at the same time that we did heat exchanger maintenance (boil out) and replaced all of the coolant lines, including the raw water lines.  Thus the likelyhood of obstruction is low.  I suspect that it may be face of the pump housing is less than fair and there may be issues with the seal.  If so, the proper technique would be to refinish the face to ensure that the surface is flat.  There is discussion in the archives regarding system troubleshooting and priming, and I have reviewed this.

Just curious if anyone else has had a similar problem when installing this kit.

Cheers,

Mike

[Stu Jackson]

Mike

Interesting observation.  I was under the impression, perhaps mistakenly, that folks used the SpeedSeal with only the Sherwood pumps because the Sherwoods have that annoying screw-in-the-back assembly, where the Oberdorfers have the easily accessible screws in the front.  I also thought the SpeedSeals have an O-ring to replace the paper gasket.  Only thing I can think of is that the O-ring is a bit too thick, and if you can get one of the same size with a smaller diameter thickness then the face of the seal might work.  It sounds like the face is too far away from the forward side of the impeller.  With the built in O-ring in the new SpeedSeal face, I don't think refinishing the face would help you, since the face is new.  The suggestion to refinish the face was for the OEM Oberdorfer cover with the old paper gasket.  Only other thing is if still returnable, is to go back to the OEM faceplate.  I've never had trouble getting mine off with the four screws, access is great.  I thought about the SpeedSeal, but didn't go for it basically because of the second sentence above.  Good luck.  Hope others can help more.

[Tom Soko]

Mike,
If you installed the speed seal at the same time you flushed the cooling system, I would venture a guess that the pump is working perfectly, but you have an air lock somewhere in the cooling system.  This would easily cause overheating.  Have you tried isolating the pump (take off the outlet hose and put it in a bucket for a few seconds?) to see if it really is the culprit?  Most likely spot for the air lock is the hoses to/from the water heater.  Lots of posts on clearing an air lock.

[Ron Hill]

Mike : Think that you changed too many different items at the same time. 
I've always advised people to do one thing at a time, and run the engine in between each.  Then you know if you did it correctly. 
Now you're going to have to redo each one until you isolate the problem.   

[Mike Vaccaro]

Gents,

Thanks for the replies. 

If anyone installs a speedseal on an Oberdorfer in the future:

1.  The seal at the pump face can be the culprit if your raw water pump cavitates (the engine cooling system was properly primed).  Pump cavitation may be detected by high coolant temp, lack of water in the exhaust and a dry pump when you remove the face the raw water pump vs. a simple over-temp--as would be the case if there was an air lock in the engine coolant circuit.
2.  If there is any question about the condition of the face of the pump, it should be properly machined to provide a level mounting surface.  The first options to remove the pump and burnish the surface with a flywheel.  The second option is to refinish the face of the pump in place.  Remove the impeller and burnished the pump face with 220 grit (or finer) sandpaper.  This technique would require a perfectly flat sanding block and a thourough cleaning of the pump after refinishing.
3.  Access to the standard Oberdorfer face plate is quite simple.  The advantage of a speed seal installation is that a) the paper gasket is replaced by a rubber O-ring; and b) it's possible to change an impeller in under two minutes.  Since we've invested so much in the boat, our basic philosophy is to improve as much as we can whenever we do maintenance, with an eye to making future maintenance easier.
4.  Culprit in our case was the face of the pump housing and a worn cam.  We chose to burnished with 220 grit and then followed up by polishing with 600 grit.  It was necessary to re-touch the cam after it was installed to ensure a proper mounting surface.  Then installed the speed seal plate in accordance with the supplied instructions.  After priming (using Ron Hills two person technique), everthing worked normally.  The quality of the speedseal kit and the product support during this process was outstanding.  Anyone faced with a worn pump face plate should consider replacing the stock plate with a Speedseal.

Cheers,

Mike