March 30, 2009

3.30.09 mystery solved

Well…..Jim was right….all that stuff in the heat-exchanger ..was old impellers.  Today he took the raw water pump apart and the impeller was still in 007

In his right hand is a piece of the trash he took out….and in his left is the impeller. He replaced it with a new one.  Here is a close-up of the reason 004 c

It is already showing signs of cracking. So……..if you’ve checked your impeller…. and pieces are missing….take the inlet side of the heat-exchanger off…..that’s where they are. We cant tell if these are what’s left of one impeller or the remnants of many impeller changes over the years. With the way it is designed, Jim feels at least half of the water-flow was restricted. 

From Jim’s days of racing, engine building and truck-driving…he has learned to check his gauges regularly….. He never say any signs of over-heating …but it may have in the past, when the last impeller failed.

Here’s another look at the end of the heat exchanger and all the stuff he got out of that top third..evidently that is where the greatest flow is.heat exchanger    stuff 001 Jim checked the thermostat by putting it in a pan of water with a thermometer …heated it up …and made sure it opened at the correct temperature….it did.

Since there hadn’t been an over-heating problem…Jim almost didn’t take this apart…he just likes to see how things are made and work….sure glad he did.  I wonder how many old impeller parts it would take to shut the water flow down completely. Engine running hot…and you cant figure out why?…..might want to check here.

This might all be old news to most of you Nissan LD28 owners….but this is our first and we were quite surprised. Jim says he is learning a lot more than he really wanted to.

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