water pump performance?

[aboyandhisdog]

Can a water pump be going bad even if it isn't leaking?  I run hotter than I'd like - especially in the summer heat.  Have R&R'd the thermostat with a 160, flushed the system several times, had the radiator gone through a few years ago, and have a good fan shroud and good radiator fins (not all bent up).  The only thing I haven't cracked open yet is the water pump.  I don't know how old it is - maybe pretty old.  Just wondering if it can be delivering poor performance even though it isn't leaking.  Thanks.

[1955CJ-5]

I would not think that the impeller would wear. If the shaft is starting to tighten up the fan/pump may not be turning quite as fast as it should, but I'd think the fan belt would start complaining or would wear quickly.

Are you running 50/50 water/antifreeze, or just water?

Plain water is supposed to be more efficient, but you also need the corrosion/freeze/boil-over protection that anti-freeze or other additives provide. So there is a compromise.

Red Line "Water Wetter" is an additive that can help cooling efficiency.

If the timing is retarded then the engine can run a little hotter.

Are you using the dash gauge or checking it some other way?

[RICKG]

Hi-Ya Tom, I know your jeep and I see how you maintain it, I gotta believe all systems are in working order. I'm with Randy on this one,  make sure your timing is correct and start checking temps with an alternate gage or infrared.. Muley

[aboyandhisdog]

I do run 50/50 with a wetter - I think maybe HyperLube, and I do believe the timing is right on for my altitude and I even advance it a bit when at the FCT.  Jeep runs great!  I have an infrared temp gun and am wondering where, exactly, would you point this to get the most accurate reading of the water temp?  Right next to where the gauge goes into the block???

I too don't see how the impeller could wear and would be interested to hear from anybody who has ever seen wear. 

Randy, I actually have been hearing a slight fan belt squeak lately and thought maybe this could be related.  The belt is new as is the alternator and belt is adjusted, so maybe the pump bearings are starting to seize slightly???  Thing is, seems to have been running hot for a long time - long before the squeak.  Maybe I will just swap out the pump and see what happens.

[athawk11]

I agree with Randy.� I don't think the impeller would make contact with the pump housing, and get shredded, unless the bearing was shot.� If the bearing fails, then the seal has probably failed and is letting water into the bearing. If the seal fails, it would normally leak out the weep hole.� I would add...I had a water pump fail.� I did not notice any change in how hot the engine ran.� It just leaked.

I would suggest a timing issue too, but I think I remember you're running about 9� advanced.� Maybe too advanced?� Although, I am probably advanced about 7� and don't have heat issue.

Excuse me for rambling on.� I'm sort of thinking out loud.

Could be your temp gauge.� Point the temp gun at the head in a number of locations then calculate the average.� You will find that the engine is warmer toward the firewall.

[RICKG]

And Yep the temps are hottest between 2-3 cyl, thus the placement of the sender..

[athawk11]

How about the radiator shroud and shroud seals? 

[1955CJ-5]

I do run 50/50 with a wetter - I think maybe HyperLube, and I do believe the timing is right on for my altitude and I even advance it a bit when at the FCT.� Jeep runs great!� I have an infrared temp gun and am wondering where, exactly, would you point this to get the most accurate reading of the water temp?� Right next to where the gauge goes into the block???

I too don't see how the impeller could wear and would be interested to hear from anybody who has ever seen wear.�

Randy, I actually have been hearing a slight fan belt squeak lately and thought maybe this could be related.� The belt is new as is the alternator and belt is adjusted, so maybe the pump bearings are starting to seize slightly???� Thing is, seems to have been running hot for a long time - long before the squeak.� Maybe I will just swap out the pump and see what happens.

Might just be best to get a new pump as you mentioned.

While the radiator is out you can back-flush it, or use something like Evapo-Rust if it seems necessary.

 https://www.summitracing.com/parts/sum-tc001?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-summit-racing&gclid=EAIaIQobChMIz53Zy-Di1wIVAWx-Ch2oaw6SEAQYASABEgJOLPD_BwE

You may also be able to see into the block and check for rust buildup....an old speedometer cable on a drill can be pushed into the block to loosen rust deposits.

I've seen pictures of water pumps with an impeller blade partially broken off......you never know..

Randy

[PercyUK]

Hi, just a thought but if you have not already done it I would also check that the thermostat is actually opening fully. I would remove it and see if the problem disappears.

[aboyandhisdog]

Thanks guys -  I'm getting some good input here. 

Percy, I did heat both my new and old tstat on the stove before install and they both worked exactly the same.  I was somewhat surprised though by how small the opening is even though I'm sure they are opening fully.  And yes, I did drill the hole(s) which let the air pass through. 

Randy, I do think I'll try the Thermocure that you suggest.  I've been using a flush like Peak or Prestone in the past, but now think maybe they don't have the power to really do the job.  Eight years ago I bought this engine from KW when they were selling a boatload of engines that a guy brought in from overseas.  There is a rebuild data plate on it that references that it was rebuilt at some point in "Ankara".  I can only guess that it ran a compressor or generator or something in Turkey.  Also guessing that maybe they didn't use antifreeze and that it may have had just plain water in it for most of its life.  It may be more corroded than I think and just not transferring heat well anymore.  I won't be able to get to this until after the first of the year, but if I have any success or other findings to share I will do so.

Thanks everybody for your ideas!

[Lee]

Tom, I went through like issues with Dads Jeep years back, and much agree with the opinion of the others. I have found that a Go- Devil with an overbore of .040 and bigger is more sensitive to heating like your expieriencing depending on the thickness of the cylinder wall casting, some are very thin, some not and I believe the casting were not consistent, but that you cannot change short of boring & sleeving. The other Key issue in this is the timing, again, in my situation I discovered the advance weights/springs were excessively worn and with my timing set at 5 deg. At full rpm I was actually well north of full advance. After tightening these worn parts and having the timing set correctly I rarely run over 190 deg unless pushing it hard. Seems these engines were rebuilt in many cases several times over the years and nothing was ever done in the distributor. My new engine was sleeved back to std bore and I seldome go north of 190.

Lee

[aboyandhisdog]

Interesting, Lee.  I'm pretty sure that this engine is .060 over so maybe that has something to do with it.  I have the electronic distributor and have been really happy with it, but don't know if it would advance more than a points distributor or not.  The jeep runs great and I have no reason to believe my timing is off (no ping, good power).

Honestly, this may be a non-issue and an issue that a lot of jeeps have.  I find that typically under a slight load ( like a long pull up a gradual slope), I will run a temp of whatever the ambient temp. is outside plus 110 degrees.  So, if it is 70 out I run about 180.  But if it is 90 out I will run about 200.  But if I'm heading up a steep grade for a period of time, I may even hit 210.  Not often, but it happens.

Last summer Lew, and Terry and several other folks headed up Gold Hill west of Boulder for the day.  After a long pull we all stopped for a while.  I looked at every temp gauge and they were all pegged at 210 or even higher.  Except for Terry and he was only at about 190.  I know he has the 160 T-stat like mine, but nothing else exceptional that would keep him so much cooler.  Would love to get there, but now I'm thinking maybe it's not possible! :-/

How cold are you there?  Any snow on the ground?  Don't put that nice truck through the ice!

[Tumbleweed]

Hey Tom,

I am also at .060" on my engine and 160 degree thermostat. Mine does not get to 200 even in the summer in Texas.

I guess if you had a spare water pump it would be easy enough to change the old one out and do a good flush with the new pump. I'm not being much help but wish you luck in finding the solution.

[aboyandhisdog]

Now THAT'S interesting!  I think I would run over 200 a lot of the time in Texas.  I bought a quart of that Thermacure and a new Airtex pump and the plan will be to flush it and change the pump within a month or two.  If I can get a handle on this it might help a lot of the guys who are running hot.  Really interested to have a look at this pump when I get it out.  Thanks for the input, George!  Have a great winter.

[Tumbleweed]

Thanks Tom and I look forward to seeing you in 2018 for sure!

Merry Christmas