Atomic 4 Water Pump and Thermostat

[ail-say oat-bay]

Any experience out there on the best place to obtain Water Pump and Thermostat for Atomic 4 original raw water cooling, and how to insure get the right ones?
Replace impeller this week and discovered Water Pump main body seals leaking and thermostat gunked-up. cleaned thermostat and working ok for now but opening late.
Thanks,
tom

 

[tenders]

Get thyself to moyermarine.com, and you'll find the finest support for your engine that exists perhaps for any old engine in the world.

Register for their forums to look around at the EXTENSIVE maintenance and operation advice and Q&A that has built up over the years.

 

[Rob Salinas]

Moyer Marine

+1 on that. Also the Moyer Marine Service Manual, or "A-4 bible" IMHO is a must have
Cheers,
Rob

 

[adam]

Ebay is another good place to look. I picked up a great condition water pump for a very good price last year.

 

[ail-say oat-bay]

Thanks

Thanks Folks,
Yes, Moyer was the first place I went, but the prices seemed high.

Also I was somewhat confused by all the choices i.e. old style, new style, 160degree, 140degree, flange style pedestal style, oberdorfer, etc.
Mine is 1977 Raw Water cooled only an has not been upgraded that I know of so im guessing the old style oberdorfer which in the picture has a grease cup like mine, but I hate to guess for this much money. On the E27 the Water Pump is very hard to reach, and even harder to see, so have to kind of work by feel, backwards. My Thermostat on the other hand is easy to reach. I believe my thermostat is 140degree, but even there they list a early model and a late model. I wonder what they consider "early" and "late".

Now that i have thought more about it I am more concerned with getting the right model than i am the price anymore. I would gladly pay the price if I could be confident I was ordering the correct match.
tom

 

[paul culver]

Can't remember if I read it here or another site but apparently soaking a sticky or stuck thermostat in vinegar can sometimes restore functionality.

Paul
E29 "Bear"

 

[Walter Pearson]

That lower bolt for the water pump is usually the one hardest to reach. You can replace it with a longer bolt whose thread length is a little more than the total length of the old one. With a nut jammed at the start of the threads, it makes a fastener with its hex head sticking out beyond the pump and is easier to manipulate. I think you can buy one of these, but it's not hard to fashion it.

 

[tenders]

You can horse around trying to codge together all kinds of A4-compatible parts if you want, or you can just go to Moyer and get the perfect part the first time. And the advice you need to make it work. And probably a hundred posts from other people talking about how they did it on their specific boats.

I buy spark plugs locally, but everything else I get from Moyer. Maybe this costs me $25 a year that I could possibly save if I spent a lot of time looking around, but it isn't worth the risk of getting the wrong part and my time is worth a lot more than $25 (to me, at least). I'll buy cheap tools for projects I think I'll do only once, and I'll buy cheap ice, but trying to minimize engine part costs is a waste of time and peace of mind. His specialized water pump is the best there is for the A4, ESPECIALLY if yours is hard to access. Also, his "Extendo" bolt for the water pump. And the carb intake thumbscrew, the carb mix thumbscrew, the electronic ignition, the CORRECT coil...the only enhancement of his I haven't put onto my engine is the antifreeze cooling, and fortunately I haven't needed many rebuild parts.

All those terms you mentioned that sound confusing are not really complicated but are meticulously documented on his website. And if you don't understand what they mean, rest assured the person you're buying from will either need to know or will not know, and you are going to end up with the wrong part. Half-a$$ed parts like bad head gaskets and water pump seals translate into screwed-up engine, and were the reason A4s developed a bad reputation after Universal stopped making them - well, that reason has gone away entirely due to Don Moyer's efforts.

Old style - older engine shape with a distinctive "tombstone" cover; a small number of parts fit the old but not the new and vice versa (I believe all consumable parts like pumps and gaskets fit both old and new)
160 degree - temp you can run at with antifreeze cooling (this determines which thermostat you use)
140 degree - temp you can run at with raw water cooling
Oberdorfer - type of raw water pump, says OBERDORFER on the impeller cover, I believe this term exists to distinguish the stock A4 pump from the Moyer version, which has sealed bearings and thumbscrews on the impeller cover - it is a significant improvement over stock. I've rebuilt the Oberdorfer pumps several times and never ended up with a great outcome. The Moyer pump will probably never have to be rebuilt.

By the way, I don't run my raw-water-cooled engine with a thermostat, and haven't done so for 21 years. I've blocked off the bypass at the tee coming out of the side of the head, forcing all the water from the pump through the head for maximum cooling effect. Yes, the engine runs cold, and I head off sticking valve potential by adding a few ounces of Marvel Mystery Oil to the fuel, but the engine will not overheat...and overheating is death to these engines.