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I recently joined the PAS and to my surprise and the luck of timing, found and purchased a restored 1929 roadster. I am a novice to pre-war classic cars and I am having some teething pains with this car but so far most issues are being resolved with basic tune-up types of repairs.
I was told by Ed Minnie when I first got the car to check the oil and water after each hour of driving. I have noticed that there appears to be a significant (to me) amount of coolant consumption. I filled the radiator to within 3-4 inches of the top so the fins are completely covered, but at least 3 inches below what looks like a drain tube in the radiator neck. Looking under the car there are no puddles or fluids dripping that I have noticed. After each drive of an hour or less, the coolant level is below the metal fins and I need to add 1-2 gallons of distilled water to get it back up to the level it was before the drive. I recently checked and regapped all the spark plugs and they looked dry and had a brownish color at the tips although one was a little darker than the others but not extremely different and definitely not wet or sooty. I have also noticed what I think is a lot of condensation/water behind the car on the floor of the garage after starting it (probably no more that an ounce but enough to make a small puddle), but no white smoke behind the car while driving.
So, is this normal coolant consumption or could I have an internal leak (blown head gasket) or other problem?
Robert
A compression /Leak Down Test is where I would start to prove/disprove the internal issue.
What color, if any is the exhaust smoke? White could indicate coolant burning(steam).
I have a link to a chart for analysis of exhaust smoke.
Good luck
Thanks for the quick replies.
Roger – The compression/leak down was next on my list.
William – I have not gotten out of the car to carefully examine the exhaust (I have been focused on driving and working out some engine running issues. At the moment all I can say is that I did not notice any obvious white smoke in the rear view mirror as I drove the car. I will now specifically look at the exhaust to check this.
What is considered “normal’ coolant consumption?”
Since it is a closed system (with the cap on), I would think evaporation and leaks are the only factors that would generate coolant loss and evaporation would be minimal. I have never seen a value for “Normal”” coolant loss.
Is there any water in the oil or does the level rise when you check the dipstick?”
William – I have not notice any obvious water in the oil, but I have not driven it much while I have been sorting things out. Now that I am more focused on this issue, I will check again tonight looking specifically for water in the oil.
Robert give me a call tonight on my cell…..Ed
Hello Robert, I’m happy to hear that you purchased that nice ’29 Roadster.
The first thing I would do is to re-torque the cylinder head. These flathead engines with a wide head, a thick ‘copper sandwich’ gasket need to be re-torqued at least 3-4 times before the head gasket has stopped ‘relaxing’ or compressing. If the head is not torqued tight enough, some coolant can be drawn in and burnt, or some compression gasses can be pushed past the head gasket into the coolant and cause excess coolant to be pushed out the overflow.
If you are running pure water in your car that is a step in the right direction, but If you are using distilled water, I’d add an anti-corrosive agent like PennCool 3000, or similar for an unpressurized cooling system. Distilled water is more ‘active’ in corroding the parts of the cooling system, some form of anti-corrosive should be added.
If you are running antifreeze, it tends to foam when run in an unpressurized system. My cars will hardly use any coolant all summer long on water. But in the fall when I switch over to antifreeze, if I take a car for a drive, I almost always get foaming and loss of antifreeze/coolant.
Some of our cooling systems take a bit of TLC to get sorted out. Typically, a Pierce water pump has more flow capacity than the radiator, even when the radiator is new. What happens then, is the water pump pulls a negative pressure on the bottom of the radiator, so much that in the cars with a long rubber hose from the bottom of the radiator to the water pump inlet, this hose MUST have a coil spring inside the hose to keep it from being sucked flat. Your ’29 should have two short hoses and a pipe in the middle between the radiator and the water pump.
Once the radiator has some use, it tends to collect rust flakes, water pump grease that gets past the pump’s bushings, and hard water deposits with some well water. These tend to clog up or at least restrict the water flow through the radiator, The pump’s abilities don’t change, so it pulls even more of a negative pressure on the radiator.
The shaft of the water pump, the hoses and hose clamps can let air be sucked into the cooling system yet NOT leak water out when sitting and not running.
I’ve personally experienced this, on a tour in my first Pierce, it was using a lot of water, and people behind me told me they could see it discharging out the overflow under the car. I talked with a knowledgable guy with my same model Pierce, and he asked if my lower hose clamps were tight. I thought he was nuts.. But two of the 4 hose clamps took about 1/4 to 1/2 a turn to get really snug, and the car stopped pushing water and foam out the overflow. A worn pump shaft or poor/old packing can also allow air to be drawn in past the packing.
What I think happens is that the air is pulled into the cooling system, it is mixed with the water by the water pump then the air/water mix or foam is pumped through the engine, where it is heated enough that some of the air bubbles become steam. This mix takes up a lot more volume than pure water, so the system is too full, and the excess goes out the overflow tube.
Some people have discovered that the engine has created a lot of rust flakes, even if it is a fresh overhaul, there will usually still be some pieces in the engine.. These tend to be deposited in the top radiator tank, and block some of the radiator tubes. You can ‘sweep’ the top tank with a magnet on a flexible wand, and see if you pick up any pieces.
There are two ‘favorite’ methods of catching rust pieces in out old cars: one is a filter called the ‘Gano-Filter’ it is a plastic tube with a cone shaped screen or filter that is put in the inlet to the radiator at the top hose connection.
Or, use the ‘footy’ hose ‘socks’ or the foot end of a panty hose, poke most of the foot into the inlet pipe on the upper tank of the radiator, but keep an inch or so outside the tube, Roll it over the outside of the inlet tube, then push the rubber radiator hose over it to hold it in place, Clamp the hose as is normally done. This footy from a ladies’ hose works very well, and often can be seen through the radiator cap/neck. If visible, the sock can be inspected to see if it has caught a lot of rust flakes, and needs to be replaced or cleaned.
If your radiator has a lot of rust flakes already, a reverse-flushing will blow most of them out the inlet or neck of the top tank.
I hope the above information helps you sort out the coolant loss you are experiencing.
Greg Long
Greg,
Thank you for all the excellent suggestions. To my knowledge, it was initially a mixture of coolant and water. I have been adding distilled water to replace the loss. Once the issue is corrected, I will consider the options you mentioned.
By the way, what are the torque spec’s and order pattern for torquing the head bolts?
Robert
Robert,
The PenCool 3000 additive for distilled water which Greg has mentioned above can be purchased at any Kenworth / Peterbilt (or the equivalent) heavy truck dealer parts counter. One small bottle treats 4 gallons of water.
Good luck,
Stu Blair
http://penray.com/products/pencool-3000-with-stabil-aid-cooling-system-treatment/
As a side note, Robert had contacted me a little while ago, on the coolant loss…my advice was to get the correct grease in the water pump, and add a flow restrictor in the top hose. I know this is subject for debate, but I had a lot of liquid overflow my ’31 radiator when I let off the gas at speed. I took a freeze plug the same OD as the ID of the top radiator hose, drilled a 5/8 inch hole in it, and installed it right against the top radiator neck inside the hose. These two things eliminated all “coolant usage”” and the car runs well within temperature limits in all degrees of weather. Just my two cents…”
Hi Robert, I would use 50-55 ftlbs. You can post that question on this thread and see what other’s say.
Pierce did not publish torque specs, nor did many if any other car manufacturers prior to I think the late ’30’s.
The pattern is from the center out, I use the torque wrench to break loose each bolt, just enough to free it from being stuck, usually about 1/8 turn, no more than 1/4 turn, then reverse and tighten to 50#. do the three down the middle, actually it’s 4, since there are bolts on each side of the distributor. Then go to the next row of 3, either left or right of center, repeat the break loose and re-tighten on each, then go to the row on the opposite side of center. This left-right pattern is not exactly what is published in the Motor’s manuals in the mid and late 30’s, the published pattern has a left-right criss-cross pattern working from the center out.
It’s hard to explain, but since this is a re-torque, the criss-cross pattern is not critical. It is important on a new installation of a new gasket.
IF you find the bolts break loose at say 40# you can bring them back to 45#, then once the whole head’s pattern is done, go back and do them again at 50 or 55 ftlbs. The main idea is to bring the holding pressure on the head gasket up gently in steps, getting all the bolts to work in unison.
My ’25 S80 touring car had had the head gasket replaced in ’98, by the previous owner, I bought the car in june of 2014, and toured with it at the ’14 national meet in Warwick RI. On the third day, I noticed that I had started to get water out the overflow on long slow hills. I found the head nuts at 25-35#, and on those engines I use 45-50# torque. Torquing the head stopped the water loss out the overflow.
The reason distilled water is bad, is that when distilled, all the impurities on the water molecules are eliminated, this leaves the Oxygen molecule able to react with metals, and creates accelerated corrosion. I use just regular drinking water sold in gallons, or if at home my own well water, which is pretty good water. If you do use distilled, add some anti corrosive additive just to be sure you are not creating additional corrosion in the system..
Greg
Has anyone used Water Wetter? I use it in post WW II cars (sorry for discussing these cars, Ed!) on break in, and it drops the coolant temperature up to 25 degrees. Many folks don’t realize that anti-freeze actually reduces the temperature transfer properties of the coolant system, as does a water pump that works too efficiently or quickly, as was already discussed in this thread. To add to David’s comment earlier, Robert is also working to adjust the timing, and borrowed the hand crank from my ’29 to better set the timing on his engine. Clearly, misadjusted timing can also affect the engine temperature and performance,as well as the engine temperature. It is likely, however, that the head gasket, constricted radiator, or some other issue is affecting the coolant issue more than the timing.
Iam surprised that a water pump that causes cavitating doesn’t get a mention here >>>>>GEOFF MARTIN
Cavitation in centrifugal water pumps is a whole scientific study. Just Google it to get some idea of the problem. Commercial pump manufacturers have tables with their recommendations for flows etc.to eliminate cavitation. If bad enough it “eats” away at the pump impellor, shaft, & pump body. There has been a number of threads on the Message Board & in the PASBs over the years. But basically it boils down to introducing some sort of restrictor on the output side of the pump.
1929 Pierce water pumps at 40 odd gallons per minute (They were proud of the fact!!)are prime candidates for cavitation. Have fun
My Series 33 experience coincides with the comments by Dave, Geoff, and Jak. Correct water pump grease solved the cavitation issue and flow restriction kept the flow at a pace so it’s not getting backed up and thrown out the overflow. A third complicating issue was a bad point which threw the timing off creating heating issues under load. New points and reset timing fixed that. Now it runs right in the middle of the motormeter where it should. Turned out to be one of those somewhat vexing multi-issue deals.
Thanks to all of you for the excellent ideas and suggestions. I am having a great time working on my car and I know with patience and perseverance, I will get this car sorted and tuned in.
I now have several very good suggestions to approach the coolant loss issue and I will test each one at a time. I know I will eventually figure it out and learn a lot along the way.
I feel like I am ~80% there with regards to how the car runs after adjusting the timing. While the car is running significantly better, I am now having some intermittent back firing issues which seem to occur during deceleration but again I will work through these to get to a 95%+ smooth running and reliable car and have fun on the way.
This is a great group and I appreciate all your help and suggestions. I look forward to meeting many of you in Buffalo this summer.
Robert
Robert…….remember……drive it like you stole it!
Ed, I completely agree! I am a firm believer in “They were meant to be driven”” and driving a classic car is a whole new experience for me and an absolute hoot! I can’t get enough of it 
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