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Cool upper rad hose?


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Hey guys, this is kind of a spin-off from my last no-start thread regarding my fuel pumps. But I had totally forgotten about another issue I had while flushing the cooling system. I had my truck idling for about 20 minutes before it shutdown, and the entire time, the all the hoses got very hot except the upper radiator hose, and coolant was not cycling through everywhere while I had the cap off, just kind of started to sizzle. So I put the cap on, and pressure still did not build and the upper hose remained cool. Is this probably a waterpump? If so, I would like to replace it while I'm doing my pumps. However a scarier issue I read, was possibly the front of the crank being broken? To make it worse, I noticed the night before the truck shutoff that the damper was a little wobbly, therefore, I bought a Fluidampr with my pumps. Should I pull the valve cover and rotate the motor with a wrench and watch for all the valves to move? You guys helped me out a lot so far, being new to my diesel, so hopefully I can get some good news on that at least. Thanks

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If you noticed this only immediately after changing the coolant, there is a specific process of replacing the engine coolant whereby you have to completely fill (or mostly fill) the coolant system "before" running the truck otherwise you can build an air gap. If you read the service manual, it refers to something called a "jiggle pin" which is the reason for this process. Asking what the jiggle pin was, I could get no one who knew but some thought it was the two small pins on the side of the OEM thermostat.

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If you noticed this only immediately after changing the coolant, there is a specific process of replacing the engine coolant whereby you have to completely fill (or mostly fill) the coolant system "before" running the truck otherwise you can build an air gap. If you read the service manual, it refers to something called a "jiggle pin" which is the reason for this process. Asking what the jiggle pin was, I could get no one who knew but some thought it was the two small pins on the side of the OEM thermostat.

Here's what I did: -drained -flushed/backflushed heater core -replaced t-stat with NAPA one -flushed block with garden hose til it flowed clear out of heater core line from back of block -flushed radiator with water -added two bottles of Prestone super rad flush, topped off rad with water (however it didnt take NEARLY as much fluid as what drained out out of it) -left cap off and started it, so it would bleed and I could top off as needed Obviously it never bled, so I couldn't top it off, closed the cap hoping to build pressure, motor shut off shortly after. Never heard of the jiggle pin lol. But is there any way to test the waterpump while the engine can't run? If it needs replacing, this is my time to do it.
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Sounds like an air lock. You might want to just drain everything out, refill with a a few gallons of fluid and remove the thermostat. Run it to make sure you get full circulation and then put the thermostat back and top it off. You may loose a little fluid putting the thermostat back but at least you'll know its working.

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When I finish draining and flushing my cooling system, I refill through the thermostat opening 'only' with premix 'slowly' until totally filled. I know al air is out. Then install the thermostat and housing and cap off the radiator. Never have an issue of an air lock since it's only takes a quart or less to cap off radiator and upper hose. And to play it safe, I always change out the thermostat each coolant change. I feel my engine cost to much to to replace by saving the extra couple of bucks by reusing the stat.

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^^^^ This is what I do too. I pull the heater hose off and when coolant gets to the top of the copper bung I put the t-stat and housing back on and then fill from the radiator. When you idled your truck for 20 minutes did you ever check the temp? When I flushed mine, I did like you and ran garden hose till it was clear and then added the flush but then took it for a 30 minute drive and got the temp to 190. If you dont have any coolant in it yet just go get you a new water pump, I just got another new one and it was $49 from napa. The bosch I got from pepboys had a ring welded to the impeller and did cool like it should have but the one from napa looks like the oem unit. Napa's True Flow part #43526

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When I finish draining and flushing my cooling system, I refill through the thermostat opening 'only' with premix 'slowly' until totally filled. I know al air is out. Then install the thermostat and housing and cap off the radiator. Never have an issue of an air lock since it's only takes a quart or less to cap off radiator and upper hose. And to play it safe, I always change out the thermostat each coolant change. I feel my engine cost to much to to replace by saving the extra couple of bucks by reusing the stat.

I do almost the exact thing... I pull a heater hose and fill tilll the heater hose trickles a bit of coolant then hook up the hose and fill the rest of the way.
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Yes, see this is what I SHOULD have done first, but then the truck shut down and I'm in the middle of my current LP and VP predicament in my very first thread a couple days ago. But now, the block is full to the top of the copper heater hose, and I even added some to the upper rad hose before tightening it back down. However, now the truck isn't starting so I can't test it. And I will DEFINITELY buy a new waterpump at NAPA if it's only $50. Wow, I was expecting to see a 150+ price tag for it. I'll pick up the pump tomorrow, but only time will tell when I get my new parts and install them next week. I'll keep you guys updated on how it's going and thanks a lot for the help so far.

BTW, since no one mentioned anything, I'm assuming it doesn't really sound like I damaged the crank? I mean, the truck has 200k, and is pretty stock as far as I can see, so I would be very disappointed and suprised to see such a great motor die at such a young age... I know the previous owner towed a camper, but that's all I know.

--- Update to the previous post...

Oh yeah and yes I did watch the temps, it VERY slowly crawled halfway between 140 and 190 in the 25-30 minutes before it died.

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You got plenty of fuel in it?

Yep. That was the first thing I checked. I was thinking maybe the fuel gauge was off. It was showing 1/4 tank, and about 115 miles to empty on the overhead. So I went to the Hess down the road, got 5 more gallons, filled it up and no change. Also, the gauge went up to about just under 3/8 tank, so I guess that means my gauge is correct?
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