Water Pump?

[atkinson40]

My 620 started overheating on the way home.   I limped it home and found water hissing from the hole in the bottom of the water pump.  Is this a water pump failure or can something else cause water to come out this hole?

 

Also, I changed out the 1600 to an 1800 some time ago.   Is the pump the same for both?

 

Thanks Kevin

[MikeRL411]

You have lost the shaft seal! Buy a new pump.

[datzenmike]

Yes that is the 'weep hole'. The intent is that owners will see this and replace rather than the water stay in and ruin the bearing and it seize up. Just get a new one.

 

It's very important that you never over heat an aluminum head. This can warp it and blow the head gasket. Worse case is the valve seats will drop out.

[MikeRL411]

1 minute ago, MikeRL411 said:

You have lost the shaft seal! Buy a new pump.

 

Nissan used to sell replacement water pump shaft seals. Made good sense from the vehicle owner view.  Too cheap! Probably have to buy a complete [hopefully not cheaply remanufactured] pump. more profit for Nissan/Renault.

[Stoffregen Motorsports]

Yes, fix it soon or you'll roast that motor.

[atkinson40]

I only drive this truck to pick up materials from HD once a month or so.  I've changed the seats to buckets, but its still an uncomfortable ride for my 6 ft, 67 year old body.

 

Every once in a while I think of getting a new pickup, but the amount of pick use I get doesn't justify it.

 

Inconsistency, over the last couple of years, it would start to get hot and I would find it was low on coolant.

 

This was not a consistent phenomenon.  Maybe only once every 6 months.  I thought maybe the radiator cap was opening and it was letting water out through the overflow.

 

Could this water pump issue be the culprit?

 

I pulled the pump, and found one in San Diego.  I'm surprised the gasket is sold separately.

 

I broke one of the bolts that holds in the radiator so will need to find a way to drill it out or make another hole for a new bolt.

 

 

 

 

[datzenmike]

Later engines used a coolant recovery system. All you need is the special rad cap, some hose and a container. After shut off on hot days the engine heat soaks and can briefly boil and over pressurize the coolant system's 13 PSI radiator cap. On yours the radiator burps out a small amount of coolant and it just empties out the overflow hose to the ground. This adds up. The recovery system allows this but catches and saves it. When the engine cools down the recovered coolant siphons back into the top of the radiator. I was topping up every couple of weeks in the summer and by winter the anti freeze was watered down. Since installing this system I top up about once a year.

[banzai510(hainz)]

Z CarDepot seels the Japan Asin(Atsugi Japan made pumps for 57$

I used to see them on Ebay and Amazon  partnumber WPN 032 I believe it is so the fan fits. But its hit miss on avail.

anything uder 30$ new is most likely chinese

 

https://zcardepot.com/collections/cooling-heating/products/water-pump-l16-l18-l20b-510?variant=31351265755249

 

ebay seems to have alot now.  I know these fit the 521 and 510 L15 fan assembles.   I know the listed list alot of later car but Im not so sure as they list even Later L series and Z series

Edited February 28, 2023 by banzai510(hainz)

[atkinson40]

On 2/27/2023 at 6:50 AM, datzenmike said:

Later engines used a coolant recovery system. All you need is the special rad cap, some hose and a container. After shut off on hot days the engine heat soaks and can briefly boil and over pressurize the coolant system's 13 PSI radiator cap. On yours the radiator burps out a small amount of coolant and it just empties out the overflow hose to the ground. This adds up. The recovery system allows this but catches and saves it. When the engine cools down the recovered coolant siphons back into the top of the radiator. I was topping up every couple of weeks in the summer and by winter the anti freeze was watered down. Since installing this system I top up about once a year.

I can find a container at the junk yard.  What is the "special cap"?

[datzenmike]

The radiator cap. It has two rubber seals. It's rather ingenious hoe it works. If overheated coolant is expelled normally and held in a container. When rad cools the air shrinks causing a vacuum that sucks the coolant back in. Naturally the recovery hose must be long enough to reach the bottom of the recovery bottle and always covered by coolant.