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spruce_ridge_beagler

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"I have an older merc. SN. 301

"I have an older merc. SN. 3017667,It has THUNDERBOLT IGNITION & KIEKHAEFER on the front cover, can anyone tell me the year.It was given to me by a relative after not being used for 5 or more years. Much to my amazement it started on the first pull ! After about a minute or so, no cooling water ? Where does the water exit & how deep should the shaft be in the water. Is it difficult to change the pump ?
Also I noticed a little fuel leaking from the lines before and after what I assume is the fuel pump but only when I initially primed it.My question is can I use regular hose,fittings & clamps or do I need crimped hoses like the factory ones ?
Thanks in advance, Dave"
 
"You have a 1971 model. After

"You have a 1971 model. After sitting for 5 years there will be a number of things that should be looked after. The impeller is most likely dry rotted by now and you should not try to run the motor again until it has been replaced.

If you plan on using this motor you really should get at least a tune up manual and follow the recommendations.

Check the compression, check the spark and install new plugs. Check all wires, lines, hoses etc. And yes, the fuel lines may have deteriorated and should be replaced, especially if leaking.

This motor has the Merc Thunderbolt II ignition - so it will still have a set of points and a condenser under the flywheel - the points should at least be cleaned and set (changed if necessary).

Like I stated above, a manual is the best route - there are numerous items that need to be taken care of and that would be the easiest way to answer most of your questions..."
 
"I replaced the impeller and n

"I replaced the impeller and now have water but at low rpms I only get steam and just a few drops, is this normal ? I noticed the shaft ,where it enters the pump housing is pitted . Could that be part of my problem ? Is there a good way to fill the pitted areas short of brazing or welding & turning back down ?
Also where is a good place to find used parts for an older motor ? I am missing some springs and a linkage rod for the reverse lock & the tilt seems to stay locked in forward gear, not good for the shallow fishing water.
Thanks in advance, I really do appreciate this forum !! Dave"
 
"No, that's not normal. Y

"No, that's not normal. You should have a good stream regardless of rpm. Are you saying that it is good at higher rpm's???

It sounds like you have an issue with a seal somewhere. Either at the waterpump end, or water-tube. There is also the possiblity that the water tube is the problem or there could be a blockage.

The easiest way to test is, remove the lower unit again, and run water directly into the the water tube. You can do this with a garden hose, restricted enough at the end that it forces most of it's water into the water-tube. If water comes out as a good stream, it's probably a seal in the water pump...

As for parts, start with this site - click on the parts section and have a look.."
 
"If your water tube and above

"If your water tube and above is good, yes, probably time for waterpump kit.

The impeller kinda works in two ways - at low rpm's it "displaces" water up the tube.

At higher rpm's it a "centrifugal" type pump. You may be "bleeding" out with the lower pressure and once "cranked up" are managing to get enough pressure to make it to the powerhead, however, I would suspect at a somewhat reduced rate from what it "could" be.

So yes, try a waterpump seal kit - usually has a gasket, plate, top end seals. Also may want to grab an o-ring (the one that goes on the drive shaft for where it fits into the pump cover - this could be a source of your "bleeding")..."
 
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