Pre Alpha Water Pump

[3victors]

Hi there, this my first time posting although I have found this forum extremely helpful in restoring my 68 Glastron 177 with Mercruiser 120hp. A few weeks ago I got the boat out and noticed I was over heating, being new to boats I disassembled the entire cooling system and cleaned out all the rust before reassembling. I then removed the lower unit and checked on the water pump which seemed to be in good shape so I put it back together and tried agin only to over heat again. I have since ordered a new water pump but I'm afraid i do not have the right part. I have attached a link to the part I have, will it work, is there anything else that could be causing over heating?

Sierra International 18-3320 Water Pump Kit https://www.amazon.com/dp/B00144D09O/ref=cm_sw_r_cp_api_t8hWxb8HTDQSQ

 

[Bondo]

Ayuh,..... Welcome Aboard,...... That kit is for a newer drive,....

You need either 18-3321, if the flush screw is on yer drive,...
Or,... 18-3317, if yer drive don't have the flush port,....

I'm guessin' yer's Does,....

 

[wahlejim]

Need to know the outdrive, pre alpha is not a model. Look through the sitckies at the top of the forum on how to id your drive. A serial number will help

 

[ThomW]

Bondo is right. The "pre-Alpha" drives will have a water pump housing base that have either a small hole in it to flush, or what looks like a small hole that is actually not a hole. I believe it will also depend on if your drive has a pre-loaded pin or not to ensure you get the right kit.

 

[3victors]

The serial number on the out drive is 2266760 I believe it to be model 120. the old pump has the flush plug but the old one does not. I am sure at this point this is not the exact kit needed, however I am wondering if it will work anyway as the parts seem to fit in place. Also having searched by the part number on the upper pump housing 46-37433 I have not been able to find a complete kit. Any idea where I could find one?

 

[ThomW]

I'm confused. You say "the old pump has the flush plug but the old one does not"? What do you mean? The base for the kit you have will not work.

Bondo, the kit you mentioned, the Sierra 18-3321 states that it is only for #1 Units with flush S/N 2495186 - 2763441. Not sure how that will effect his motor, given his serial number is 226670?

 

[3victors]

Thanks all, I have ordered the correct parts. Is there anything else I should check on while I have the lower unit off?

 

[KJM]

if the old impeller looked ok then you could also replace the thermostat in case it is stuck closed or boil it in a pot of water to see if it opens. have you had the boat running before when it didn't overheat or was that the first time you had it going? i'd also check for obvious things like clogged inlet vents on the lower drive, key in the impeller, water in the oil and is warm water exiting the prop area when on the hose.

 

[3victors]

It started over heating upon first start. I have cleaned all the rust/debris from the whole system and replaced the thermostat. There was water in the oil, but I'm unsure if it was there prior to my dumb friend flooded the engine with a garden hose in the exhaust while trying to flush the water ports on the manifold.