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Late last year I purchased a 1930 club sedan and had it shipped back here to Australia, the car arrived here in Australia in January but I have not had time to tinker with it until the last few weeks, Today I took it on it’s first test run and after driving for around 15 minutes water starts to come out of the radiator cap it mainly seems to be doing it when backing off, Just wondering if anyone else has encountered this problem with their Pierce? and if so what the cause may be. I noticed the water coming out was very foamy and is green in colour so has obviously had coolant added to the system. any thoughts appreciated
Thanks Jason
I had the same problem with my ’31 phaeton, driving along was fine, when you backed off gas water would overflow.
I took a metal freeze plug the same diameter as the inside diameter of the top radiator hose, drilled a 5/8 inch hole in it, and installed in the upper hose right at the inlet to top radiator tank. This slows down the water flow to top tank, eliminates the run over, and doesn’t hamper cooling.
If your radiator water is foaming, the cause is usually air being pulled through the seal at water pump. Make sure the packing is sufficient and packing nut drawn down correctly, and check your water pump grease (as it helps seal the shaft also). Make sure to use actual water pump grease, as it won’t be “washed away”” like regular grease.”
Excessive vane clearance from either the pump body or end plate can cause cavitation resulting in foaming and runover. I chased this problem with our 1247 for a couple of years until Scott Statsny diagnosed and corrected both clearances…with no more foaming since.
Dave
Thanks all I will check pump and if that does not fix it will put in a restrictor in the top hose
Thanks Jason
I agree with the other answers provided so far but here are a few less-invasive, and less expensive, suggestions:
1. The bottom radiator hose leading to the inlet side of the water pump originally had a pipe (tube) in the center with approx. 4-inch hoses on either end. Sometimes owners replace this with a single long straight piece of hose, which can collapse at speed under the powerful suction of the pump. A single piece of hose, if used, should have a coil spring inside to prevent such collapse. Stainless exhaust tubing is my choice for replacement.
2. If the water pump packing is deteriorated, the pump can suck ambient air which will lead to foaming.
3. Modern ethylene glycol green anti-freeze (the only anti-freeze one should use in any pre-1970 car, IMHO) will foam in an UNpressurized cooling system such as found in all Pierce-Arrows. The foam displaces water, and the hot water entering the top tank of the radiator has to escape via the overflow tube. At highway speeds it’s even worse, and a siphon effect can result to further reduce your coolant level. When I first acquired my 1934, with 50/50 anti-freeze, every 150 miles on a highway trip to the 2006 meet I had to add 3-4 quarts of water. I don’t need anti-freeze in my San Francisco area climate, so I run distilled (NOT de-ionized) water PLUS Penncool 3000 additive for anti-corrosion, water pump lube, and anti-cavitation purposes. I doubt that I add a quart of coolant in 1,000 miles now. Greg Long of Michigan puts in anti-freeze only for the winter, and flushes and uses water + additive for the touring season. Use the minimum amount of anti-freeze to prevent freezing in your climate in conjunction with a full dose of other additive(s) for anti-corrosion and lube purposes.
Notwithstanding the above, my 8s will burp when shut down. A one-minute idle cool-down after a fast run will minimize this.
If possible, top off coolant only when the engine is hot and the coolant
has expanded. Fill to about two inches below the neck, except for 1934-38 cars in which one cannot see the level until it is overfull. Hot top-off is even more important on those later cars.
Good luck and please keep us posted on what you find….
Had a little time to work on the Pierce over the las couple of afternoons so far I have drained all of the coolant out
and flushed the system and filled with water.
The bottom radiator hose still has the tube in the centre
I then took it for a test run it took a lot longer for water to come out of the cap and was not foaming or coming out as much but obviously there is still a problem.
I will check water pump packing and grease next and if needed disassemble pump and check clearances etc
I was also thinking ti would be worth while to check the flow of the water in the radiator just in case it is blocked or partially blocked.
while the engine did not overheat today it was a very mild day and I only end for around a 20mile drive and to my way of thinking the engine is defiantly running hotter than it should.
I appreciate everyone’s comments
Jason
Jason,
Do you have a laser thermometer that you can use to check for hot spots on the radiator?
If you find any, that may tell you where you have restricted flow.
You can get one for under $50.00.
Peter
Hi Jason, when new, the water pump was able to pump quite a bit more water than the brand new, clean radiator core could flow. The result is a negative pressure or vacuum on the bottom of the radiator all the way to the shaft of the water pump.
I learned that the lower pipe and hoses can leak air, when they don’t leak water. There is only about 1psi of water pressure from gravity if the radiator is full. But the water pump can pull several psi of negative pressure at normal running rpm.
I found that a ‘snug’ hose clamp on the lower pipe would let in air, but a tight one would not.. so check that the lower hose clamps are tight.
Next, use some very thick water pump grease to fill the grease cup on the water pump. The thick grease will fill up some wear-clearances. Next snug the water pump packing nut while the engine is running, not tight, just snug. If it is bottoming out, then more graphite-rope packing needs to be put in, under the dished washer..
Then, I’d go with David Coco’s suggestion: measure the OD of the upper radiator water inlet neck, Get a ‘core-plug’ or ‘freeze-plug’ from your auto parts store, drill at least a 5/8″ hole in the plug. With a good clean radiator, a 5/8″ hole might work well, but if you have a partially clogged radiator, it might cause the engine to run hot. and a larger hole needed for a bit more flow.
Then drive it a lot, watch your temp gauge.. and, if you haven’t yet, check the gauge against a good thermometer. The ‘no-touch’ ‘laser’ thermometers are available from Harbor Freight for uner $30 most of the time. [available online, but I don’t know what shipping would be to ‘down under’ ]
Or put a good cooking thermometer in the upper radiator tank and compare the reading to the car’s gauge.
If the car does have a restricted radiator, there is a way to use the engine, it’s water pump, and the heat it generates to reverse-flush the radiator, I can post that setup if needed.
Let us know what results you have.
Greg Long
I picked up this non-contact thermometer from Amazon for $19.
The unit seems to be very accurate and has a laser pointer so you can see exactly where you are getting a temperature reading.
http://www.amazon.com/gp/product/B00837ZGRY/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1
A minor nitpick: When using the infrared non-contact thermometer on the radiator, COOLER spots indicate clogs.
Also, check the temps of the outside of the water jacket plate from front to rear. If that plate has not been off in years, the cooling system would greatly benefit from cleaning out the rust, crud and corruption you’ll probably find between the cylinders, especially toward the rear. The diverter on the inside of the plate, which serves to give equal coolant to the rear cylinders, should also be cleaned or replaced.
Removing the water jacket to clean out the water circulation areas in the engine is a good idea. Be sure to install a filter in the upper radiator hose so that any material that isn’t removed during the cleaning will not clog the radiator.
“Gano”” brand filters work very well and allow visibility of contamination.”