Radiator/water pump Q for the best and brightest

300rag

It's Not Going to Shift Itself
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While inspecting our cars this week, critter and I noticed that there was a difference in the above noted items in our cars. I was taking the number from his lower rad hose so I could reference it at the parts store, and when we got to my place and looked at mine, the lower hose didn't exist in that location. Both cars are 318, non A/C, with a 19" rad. The 69 Monaco has the inlet on the driver's side, as well as the outlet. The 70 Fury has the inlet on the driver's side, and outlet on the passenger side. The upper hose is the same on both, and the lowers are different, of course. Seems odd that there would have been two different water pumps for the same spec. Anybody have a plausible reason for this discrepancy?
 
Does the Monaco have factory trailer tow? Just spitballing...
No trailer tow package. I would think with either the tow package or A/C, it would be at least a 22" rad as well. Only difference is 727 in the Monaco, and 904 in the Fury.
 
How about because Chrysler changed the design of the timing cover and water pump for 1970
That would do it. The other difference in the two engines is the PCV and the oil breather are on opposite sides. PCV on passenger side on 69, and on the driver's side on the 70.
 
So the question then becomes, is there a benefit to the new design or was it done just for the sake of change?
It is hard to tell sometimes... There have been many things I would swear were the result of an engineering group trying to justify their existence in between actual needed projects.

How about because Chrysler changed the design of the timing cover and water pump for 1970
Thanks... close enough to what I came up with cruising the parts books... but nothing else to say why. It is pretty amazing to me that so much was changed between options and years... I had always thought of Mopar's as being a bit more forgiving with parts interchange.
 
It has to be close to 40 years since I did a Tune up on a 1969 or older small block. I do believe the change was done to make it easier to set the ignition timing.
As for parts interchanging, just like you can change a new magnum block to the older 1970's LA style cover, you can change the 1969 and older covers to the newer styles or vice versa.
 
It has to be close to 40 years since I did a Tune up on a 1969 or older small block. I do believe the change was done to make it easier to set the ignition timing.
As for parts interchanging, just like you can change a new magnum block to the older 1970's LA style cover, you can change the 1969 and older covers to the newer styles or vice versa.

I am going to make a correction to my earlier statement on this, 1970 was a very pivotal year of change for Chrysler. Another reason for the change in the front cover and water pump was the fact that they also changed the A/C cars with a small block to the Dual belt design like on the big block cars.
 
Found this thread, quite helpful. I may have to redo the radiator (the water pump was rusted, and I suspect the same will be true of the radiator inside). Like the OP, I have the small block 318 V-8 and no AC or trailer package, so my Polara 'vert has the smallest radiator -- 19".

On the one hand, my restorer asked if I wanted to upsize the radiator, because he thinks mine's quite small. I've read elsewhere on this board that Mopar radiators at the time had no margin, so upsizing might be a good idea.

On the other hand, I'd like to keep things original and the outside looks good, plus the previous owner confirmed last night that he never had any overheating (or any other) issue with the car. So, I would prefer to (i) recore the original or (ii) find an OEM replacement or NOS.

Before I go for recoring, any suggestion for a NOS or OEM-like rad? I've looked up Murray Park and several other places, but the 19" does not seem to be a popular choice.

PS: I found a NOS unit on eBay, but it's for 1969 -- based on the above, that's no good for my '70.
 
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If I remember right the 19" radiator had a spacer on the one side and used the 22" core support. Measure the opening in your core support and it should be around 22". Then order the correct one. If you can get one with a fan shroud better still. Since you do not have A/C you do not need the 26" one.
 
If I remember right the 19" radiator had a spacer on the one side and used the 22" core support...

Correct...

20170512_132531.jpg
 
Thank you all. Going for a recore of my original 19" unit. If anyone finds a NOS 22", please let me know -- am still interested.
 
If anyone is interested, I found a NOS 19" for the no-AC 318 Monaco for sale on eBay. Still listed as of 9PM this evening, they are asking $339 + S&H.
 
OK, updating this thread with my experience and some more questions.

As I have mentioned here and elsewhere, Poppy (aka my '70 Polara 'vert) still has its original non-A/C 318 and 19" radiator (Part number P/N 2998951). The car had 31,208 miles when I purchased it in late March 2018. Right after I bought it, I had (i) the water pump replaced, as the original was beyond hope and (ii) the original rad recored. I started driving the car at the end of the following month, in April 2018. Now, almost 15 months later, Poppy has been to two Carlisle shows and is just shy of 33,000 miles.

Here is my assessment of the cooling performance in those 1,750 miles:

1. Once it's hot outside (80+) and we're in town, the engine quickly starts to run hot. The temperature creeps up fairly fast: after a few minutes of driving in stop-and-go traffic, the temp meter needle reaches the high end of the "normal range bar", and after less than 5' it exceeds it (while staying in the range of non-lethal temps). Not great, as I have to try and avoid such situations -- and thus I have to overthink outings and routes.

2. As for the open road:

a. Last year, I did not have any issue with temps while driving on either small roads or highways (even when keeping up with the fast traffic on the outside lane). Temps outside did not matter: the needle was between the E and the M, just where I (and @71Polara383, who test-drove it with me while at Carlisle) like it.

b. This year, I had zero issue until this weekend -- but yesterday, Poppy overheated on the way back from Carlisle. This came after less than 75' of continuous driving time: 15' in Carlisle (got hot as per usual, but no overheating), 30' on small hilly roads at 40-60 mph (the temp quickly dropped but remained a bit higher than I usually see it, about 60% of the way right in the normal temp range vs. 40% usually), followed by about 30' on Route 15 (where I spent half of the time on the passing lane, driving with the fast traffic). Right around Emittsburg, just when I was thinking that life was really great, I smelled a burning smell: I looked at the temp gauge, and boy was it hot! I pulled over, saw steam coming out from the radiator top nipple (the steam pressure had blown away the overflow hose -- see pic below). I waited 20', then added a half gallon of distilled water. Afterwards, I had to stop every 15' to let the car cool down a bit, as temps kept creeping up after 5-10' of normal driving and reached the high end of my preferred range after about 15'.

Now for my questions: why?

--> Leaks? Don't think so. I had checked coolant level before heading out to Carlisle, and only needed to add a very tiny bit at that time to cover the gills inside. Every time I stopped on the way back from PA, I checked for leaks -- I saw none. Zero, zip. No marks in my garage either, ever. At first pass, it seems that leaks are out.

--> Hose spring? Don't think so. First, if there were a spring issue, I think that I should have had problems earlier. Second, my recollection is that, when Poppy was brought back in shape last April, my restorer and I did discuss putting an anti-collapse spring in the lower radiator hose -- otherwise, collapse and starvation would have been my first suspect. Still, I'll double-check with him tomorrow.

--> The thermostat is next in the suspect line-up. The original was replaced last year, but I just looked up the invoice and I was billed $14.75 for the one installed so I have no idea which brand the new one is (I made the same mistake as with the water pump, I did not discuss choices with my mechanic and did not keep brand records for parts in the early stages of the restoration). I am thinking that perhaps the new thermostat has already gone bad and in particular, as @Big_John might say, has started "to stick or open later" -- which would explain the seemingly inconsistent temp behavior (goes a bit up, then goes a bit down) that I observed in my last 20-30 miles of driving before parking the car yesterday. Regardless, as @mr. fix it stated, replacing the thermostat should not solve the "hot in stop-and-go traffic" issue.

--> Of course, there could be an issue with the recored radiator itself. I don't think the initial re-coring was the issue (otherwise, why did the car work perfectly once underway last year?). Maybe now there is a clog of some sort, but I doubt it. Yes, there is some oiliness in the coolant (see the second photo), though, so I'll have the system flushed anyways.

--> Next, I have to worry about the water pump flow?
(i) As mentioned above, I don't know the brand of the pump that was put in. Perhaps the thermostat / pump combo is not the ideal one?
(ii) more broadly, after reading this post from @Davea Lux about the importance of keeping the "pump mated to the clutch fan and the pulley size", I am wondering whether maybe I have mis-matched components? I doubt it in my case, as my restorer is a '60s-'70's Mopar specialist, but that is always possible. A question I will specifically ask him is whether the water pump housing is still the original one, or a replacement part (thanks to @CBODY67 for making me think of this possibility, and to @Rapidtrans777 for also suggesting to check the housing).

--> Finally, the radiator I have still has the original four-blade fan, but no fan shroud. I have not been able to find any factory shroud listed for my engine, but @1970FuryConv did manage to find a shroud and spacer. I've asked him for more details about it, and will post here when he responds -- and of course I am open to suggestions (pluses/minuses).

Look forward to hearing the best and brightest's collective opinions! If anyone disagrees with part or all of what I just wrote, or if I am missing an obvious item, please let me know where I am erring.

IMG_3686 copy.jpg


IMG_3688 copy.jpg
 
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OK, updating this thread with my experience and some more questions.

As I have mentioned here and elsewhere, Poppy (aka my '70 Polara 'vert) still has its original non-A/C 318 and 19" radiator (Part number P/N 2998951). The car had 31,208 miles when I purchased it. Right after I bought it in late March 2018, I had (i) the water pump replaced, as the original was beyond hope and (ii) the original rad recored. I started driving the car that the following month, in April 2018. Now, almost 15 months later, Poppy has been to two Carlisle shows and is just shy of 33,000 miles.

Here is my assessment of the cooling performance in those 1,750 miles:

1. Once it's hot outside (80+) and we're in town, the engine quickly starts to run hot. The temperature creeps up fairly fast: after a few minutes of driving in stop-and-go traffic, the temp meter needle reaches the high end of the "normal range bar", and after less than 5' it exceeds it (while staying in the range of non-lethal temps). Not great, as I have to try and avoid such situations -- and thus I have to overthink outings and routes.

2. As for the open road:

a. Last year, I did not have any issue with temps while driving on either small roads or highways (even when keeping up with the fast traffic on the outside lane). Temps outside did not matter: the needle was between the E and the M, just where I like it.

b. This year, I had zero issue until this weekend -- but yesterday, Poppy overheated on the way back from Carlisle. This came after less than 75' of continuous driving time: 15' in Carlisle (got hot as per usual, but no overheating), 30' on small hilly roads at 40-60 mph (the temp quickly dropped but remained a bit higher than I usually see it, about 60% of the way right in the normal temp range vs. 40% usually), followed by about 30' on the highway (where I spent all the time on the passing lane, driving with the fast traffic). Right around Emittsburg, just when I was thinking that life was really great, I smelled a burning smell: I looked at the temp gauge, and boy was it hot! I pulled over, saw steam coming out from the radiator top nipple (the steam pressure had blown away the overflow hose -- see pic below). I waited 20', then added a half gallon of distilled water. Afterwards, I had to stop every 15' to let the car cool down a bit, as temps kept creeping up after 5-10' of normal driving and reached the high end of my preferred range after about 15'.

Now for my questions: why?

--> Leaks? Don't think so. I had checked coolant level before heading out to Carlisle, and only needed to add a very tiny bit at that time to cover the gills inside. Every time I stopped on the way back from PA, I checked for leaks -- I saw none. Zero, zip. No marks in my garage either, ever. At first pass, it seems that leaks are out.

--> Hose spring? My recollection is that, when Poppy was brought back in shape last April, my restorer put in an anti-collapse spring in the lower radiator hose -- otherwise, collapse and starvation would have been my first suspect. I'll double-check with him tomorrow.

--> The thermostat is next in the suspect line-up. The original was replaced last year, but I just looked up the invoice and I was billed $14.75 for the one installed so I have no idea which brand the new one is (I made the same mistake as with the water pump, I did not discuss choices with my mechanic and did not keep brand records for parts in the early stages of the restoration). I am thinking that perhaps the new thermostat has already gone bad and in particular, as @Big_John might say, has started "to stick or open later" -- which would explain the seemingly inconsistent temp behavior (goes a bit up, then goes a bit down) that I observed in my last 20-30 miles of driving before parking the car yesterday. Regardless, as @mr. fix it stated, replacing the thermostat should not solve the "hot in stop-and-go traffic" issue.

--> Of course, there could be an issue with the recored radiator itself. I don't think the initial re-coring was the issue (otherwise, why did the car work perfectly once underway last year?). Maybe now there is a clog of some sort, but I doubt it. Yes, there is some oiliness in the coolant (see the second photo), though, so I'll have the system flushed anyways.

--> Next, I have to worry about the water pump flow?
(i) As mentioned above, I don't know the brand of the pump that was put in. Perhaps the thermostat / pump combo is not the ideal one?
(ii) more broadly, after reading this post from @Davea Lux about the importance of keeping the "pump mated to the clutch fan and the pulley size", I am wondering whether maybe I have mis-matched components? I doubt it in my case, as my restorer is a '60s-'70's Mopar specialist, but that is always possible. A question I will specifically ask him is whether the water pump housing is still the original one, or a replacement part (thanks to @CBODY67 for making me think of this possibility, and to @Rapidtrans777 for also suggesting to check the housing).

--> Finally, the radiator I have still has the original four-blade fan, but no fan shroud. I have not been able to find any factory shroud listed for my engine, but @1970FuryConv did manage to find a shroud and spacer. I've asked him about it, will post here when he responds -- and of course I am open to suggestions (pluses/minuses).

Look forward to hearing the best and brightest's collective opinions! If anyone disagrees with part or all of what I just wrote, or if I am missing an obvious item, please let me know where I am erring.

I suspect from what you describe it could one of several things. Have you checked the radiator fins on the core be grass seed or other debris that prevent proper air air flow. I think that a thermostat is the most likely, many of the ones sold these days at Auto Bone and Car Crap are made in China and are very poor quality. Go on line and buy yourself a Robert Shaw heavy duty t-stat. These are made here and are the best stock type t-stat on the market. If you car had a 4 blade fan from the factory it likely did not have a clutch fan or a shroud, most of those were found on 26" radiators. Mismatched components are not likely on a 318 non A/C car. I would suggest changing the T-stat first and see if that fixes your problem. Check the water pump for excessive bearing play. Grab the fan and try to move the unit back and forth, if you observe or feel movement of the water pump shaft, the unit is failing. The other thing you might want to check is for the presence of hydrocarbons in the coolant. Most auto parts stores have a tester for this purpose. Hydrocarbons in the coolant are an indication of a cracked head or bad head gasket. If combustion gasses are being vented into the cooling system this results in aeration of the coolant (gas bubbles)
which reduce coolant density and cause heating. www.flowkoolerwaterpumps.com has the t-stats

Dave
 
As a follow up, check your lower radiator hose clamps to be sure that they are tight, aeration can also happen if air gets sucked in around a loose clamp. You might want to find out if the shop installed a new or a rebuilt water pump. Most of the rebuilt pumps these days are done overseas and the quality of many of them is also crap. I buy only new pumps at this point that are made in the US because I am old and lazy and hate doing a job twice.

Dave
 
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