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Posted By: Dave39MD 1931 Shakedown, coolant foaming - 06/19/22 10:17 PM
Like Jerry and his 29 I am also trying to work out the bugs on my 31 since it is back on the road. I did a search and it was fun reading the old reply's from Chipper, Gene, Mr.Mack, JYD , and others. After all that I should not have questions but I am slow.

So I believe air is coming past my water pump shaft causing it to foam when the engine is slowed down. I have some water pump grease and coolant coming out of the pump that is visible on the shaft . I did tighten the packing nut with only slight help. I added a ring of packing and it is still foaming when the engine slows coming to a stop.

The engine is not over heating and runs well.

Question # 1 is how tight should I go on the packing nut or where do you stop before you cause problems with the shaft over heating?

Question 2# I noticed a small hole in the radiator inlet pipe, inside the radiator just under the cap. The hole points up towards the cap. Watching it run at idle does not look like it would be a problem. Looks like a rust hole. Could this be causing my problems?

Thanks

Dave
Posted By: Harrys31coach Re: 1931 Shakedown, coolant foaming - 06/19/22 11:06 PM
Hello Dave39MD,
When you say coolant and pump grease is appearing on the shaft ahead of the water pump housing, is that the foaming that you are seeing at that location or somewhere else? Try removing the fan belt and wobble the fan/water pump shaft to check for loose play between shaft and bushing. Too much play will continue to work the packing seal and internal coolant will work past and leak. I'd say that you can tighten the packing until you feel resistance in shaft rotation just beginning. Then reinstall fan belt and tension to just snug, not loose-not tight and see how that works. No clue as to the hole under the radiator cap that you see. Is it above coolant level? I would not think that there is air in system, unless low on coolant. edit. Maybe air and coolant are swapping places like Chipper suggests.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/20/22 12:24 AM
Harry, Thanks for the reply. The foaming comes out and around the rad cap. The water pump grease and a slight amount of coolant is coming out from the pump to the shaft and the area below the shaft on the pump.

Dave
Posted By: Chipper Re: 1931 Shakedown, coolant foaming - 06/20/22 02:36 AM
If the water pump shaft is galled or too worn new or tight packing may not be enough.
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 06/20/22 03:14 AM
Originally Posted by Dave39MD
Question # 1 is how tight should I go on the packing nut or where do you stop before you cause problems with the shaft over heating?

It should leak, just not much. The water is the lubricant. It would be nice if the leak was extremely slow. A drop every 15 minutes or so might be really nice. Sneak up on it. keep making it leak a little less. On my packing nut water pump I can reach under there and it is always damp, but I never see any water on the ground. If the nut is extremely tight and still leaking noticeably the nut is probably bottomed out and it needs more packing. If more packing won't do it, The pump probably needs an overhaul.

Originally Posted by Dave39MD
Question 2# I noticed a small hole in the radiator inlet pipe, inside the radiator just under the cap. The hole points up towards the cap. Watching it run at idle does not look like it would be a problem. Looks like a rust hole. Could this be causing my problems?

I really doubt it could be a problem. If your water pump leaks excessively that is almost certainly the cause. If the water pump isn't leaking excessively, and you are using ethylene glycol coolant, you might need some coolant that foams less (Valvoline/Zerex G-05 is a good choice). It wont compensate for an water pump that leaks air though.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/20/22 10:25 AM
Thanks Chipper and Bloo!

I am not 100% but I think I put a new pump on it when I started this adventure 10 years ago. I do have pumps and shafts here if that turns out to be the problem. What is visible of the shaft does look new.

I put one ring of new packing in and it is tighten up a little past snug. I can't see water leaking but the depressed area under the shaft is wet when I get back from a run, grease coming out of the packing nut on to the shaft. I will run it again this morning and see what happens. I'll find some Zerex G-05 and give that a try as well.

Dave
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/20/22 07:25 PM
Ran it mid morning and there was no surge of foam at the usual spots in my test run. When I got back to the shop inside the cap was foamy as was the over flow tube discharge. Water and grease still getting by the packing so I am taking this as a sign to tighten up a little more.

Found the G-05 at NAPA.

Dave
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/21/22 09:40 PM
No change today. I did have my laser temp gauge and as soon as I got back I hit the packing nut and it was 142 F same as the stat housing and rad inlet. Do you think this may be reasonable? My thinking is if I have it too tight it would be getting hot so I may have a ways to go in tightening it. A slight amount of grease still easing out at the packing nut and shaft but very little water at this point.

I must not have done anything with this pump because I believe I could get another ring of packing into it.

thanks

Dave

ps This is a fun car to drive, I knew it would be so it kept me going.
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 06/22/22 10:28 AM
Just slow down the leak as much as you possibly can, but don't quite stop it. When you stop it the packing and shaft will burn up fairy quickly. It really is that simple. In the future if it starts leaking more, tighten it more. Great news to hear that it is on the road!
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/22/22 11:55 AM
Thanks Bloo
Posted By: BearsFan315 Re: 1931 Shakedown, coolant foaming - 06/22/22 12:44 PM
we call it a controlled leak wink use packing in a lot of industrial pumps in various applications. depending on the application how many drips per second/ minute you need. basically serves as the LUBE for hte packing and shaft. too loose and you loose your fluid, too tight and you burn up shaft/packing. depending on what you are pumping which cost you more wink
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/22/22 02:39 PM
Thanks Jerry.

I guess I am looking for that point where air is not getting past the packing but the shaft stays cool with a slight controlled leak. I still have some foaming. I put better bolts in the repo hose clamps on the bottom hose yesterday just in case it was not tight enough even though I did use a little sealer on the connections.

Trying to do one thing at a time so I know what caused the foaming.

I think my plan is one more test run then a new water pump, then the new antifreeze.

I hope your 29 is progressing

Dave
Posted By: Harrys31coach Re: 1931 Shakedown, coolant foaming - 06/23/22 11:27 AM
Hello Dave39MD,
Looking at 'The Filling Station' online catalog with regards to water pump parts for 1931 Chevy:
RW-145 water pump rebuild kit: $169.50
VT-27 water pump grease: $ 17.50
RW-220T water pump packing: $ 3.95
WP-836259 water pump: $ 195.00
To me everything seems pricey so before throwing out or rebuilding your current water pump, maybe you can do some testing with your pump using; Aqua Shield Grease. Look it up and read the description. It does say to use gloves as it clings to most anything.
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 06/23/22 12:28 PM
Just in case you haven't seen this:

https://forums.aaca.org/topic/375509-bloos-not-quite-scientific-antifreeze-foaming-test/
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/23/22 02:17 PM
Thanks Harry, I agree on making sure before I change any parts.

Bloo, I re read your AACA test. I do remember reading it but since I never had a foaming issue it did not stick.

It is odd that after I ran the Evapo rust treatment I refilled with anti freeze and I bet it was the same O Reilly's you had a problem with. The first time in 50 or so years of having a foaming problem. I will confirm when back to the shop.

I think I may just try the g 05 and see what that does. Maybe loosen up the packing nut a 1/4 turn to get it a little wet.

Thanks for the time and sharing of the test!

Dave
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 06/24/22 01:55 PM
Thanks Bloo!

I put the Zerex 05 in and ran it hard to my usual turn around spot and ran it hard back. Not even a hint of foam .I did loosened the packing nut a flat and have a hint of water coming out.

Looks like all I need to do is find a top and upholstery shop.

Thanks for everyone's suggestions.

Dave
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/15/22 03:35 PM
Well the foam came back but very light. I removed the water pump to check the shaft and put a rebuilt pump back on. The anti freeze is making a real mess on the new paint so I went with water. I am not sure if water even foams but there wasn't any after a long hard drive. I will also attach picture of the shaft to see what you think, it does not look real bad but I am not sure. Found what I think is a crack in my two blade fan so I replaced it with a four blade. Any ideas if the four blade is more or less a period replacement (picture attached)? I know there was a post or G&D article on fans but can't find it.

Thanks

Dave

Attached picture 31 fan impeller.jpg
Attached picture 31 fan.jpg
Posted By: TiredOil Re: 1931 Shakedown, coolant foaming - 07/16/22 04:39 AM
Here is a link to ID the fan blade:
https://1931chevrolet.com/specs9.htm
Mihaly
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 07/16/22 05:55 AM
That shaft looks like it would probably work to me, but it's hard to tell from afar. Maybe try some more packing? It must be sucking air somewhere, and the pump is usually a good guess. Water doesn't foam normally. The G-05 completely solved the foaming problem in my 36 Pontiac. Are your bushings loose? Is this pump greased? Lack of grease could have an effect if so. If it's an oiled pump, I don't know.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/16/22 09:58 AM
Thanks Mihaly, I use Bill's site a lot and that was it! The 90 degree is the replacement.

Bloo, the old pump was tight and greased. I put a new reman on it this last go around. I will have to try it with G05 again to confirm anything.

Thanks for the help.

Dave
Posted By: Chipper Re: 1931 Shakedown, coolant foaming - 07/16/22 12:48 PM
Pure water does not foam as any bubbles will quickly burst. Materials that alter the surface tension of water will stabilize bubbles resulting in foam. Soap is one that is very common. Ethylene glycol is another. Adding an anti-foam agent like silicone oil will reduce the stability of bubbles and therefore reduce foaming.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/16/22 05:21 PM
Thanks Chipper. Will soluble oil reduce the stability of bubbles?

Thanks
Posted By: Chipper Re: 1931 Shakedown, coolant foaming - 07/16/22 07:21 PM
It depends some on the formula for the soluble oil but, generally the stability of bubbles (foam) is slightly greater than pure water and much less than most glycol based coolants. However, soluble oils produce a film on hot surfaces that inhibit the transfer of heat. It takes measuring the actual metal temperatures in the engine to determine the significance of the loss (results in hotter metal). In some cases the temperature of the coolant is lower causing people to think it is cooling better which is exactly the opposite. THE CRITICAL TEMPERATURE IS THE COMBUSTION CHAMBER METAL NOT THE TEMPERATURE OF THE COOLANT. Coolant temperature is only a rough indicator of the heat removed from the engine.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/16/22 10:51 PM
Thanks Chipper. It is cooling really well and seems even cooler with the four blade fan. The four blade seems a littler noisier but not bad.

I will check the temp near the plugs before and after adding the soluble oil to see what happens.

Dave
Posted By: Harrys31coach Re: 1931 Shakedown, coolant foaming - 07/17/22 12:08 PM
Hello Dave39MD,
There is a lot of discussion about foam in engine coolant, so I did a Google search asking: 'silicone oil for reducing bubbles in engine coolant'. A response by- www.dow.com 'troubleshoot coolant foaming in six simple steps'. It might be of help to your issues.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/17/22 01:16 PM
Interesting article, thanks Harry
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/25/22 04:05 PM
I put a gallon of Anti Freeze, G05 in with the distilled water and it was still foaming. There was water /steam starting to come out of the exhaust pipe. I re torqued the head again hoping that was the problem. It stopped the steam and water but no luck on the foaming. I pulled the plugs and did a compression test. Looks like I have something going on with 4 and 5. There is also a slight rust color on those plugs. Does this point to a gasket vs a cracked head or is it too little info.

I have trouble moving these heads around when they are easy to get to. Any suggestions on how to make removal and replacement easier than it looks?

Thanks

Attached picture 31 comp test plugs.jpg
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/26/22 09:41 PM
It looks like the gasket failed but that may be wishful thinking. The head is at the machine shop so I should know in a few weeks.

Dave

Attached picture 31 head repair 2.jpg
Attached picture 31 head repair block.jpg
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 07/26/22 10:03 PM
Yes, that's definitely bad, and it must have been blown into the water jacket as well to give you all the bubbles. I am a bit surprised your 'blue liquid' didn't find CO2 in the radiator, though I have seen that a time or two before where it failed to catch a combustion leak into the coolant. It usually doesn't miss, and if it turns yellow there's no doubt.

I'm glad you have finally found it I would take a straightedge and feeler gauges and check that area for warp, both on the block and head. Keep us posted!

P.S. Whats this little yellow line? Is it just an illusion or is it a trail of some kind?

[Linked Image from i.imgur.com]
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/27/22 01:15 AM
Thanks Bloo you helped me get my steps in today walking back to the shop, that sure looked like a crack but it must have been some gasket trace.

Here is an updated photo of the spot.

Thanks

Dave

Looks like a wire in the coolant jacket, is that common?

Attached picture 31 head repair 3.jpg
Posted By: bloo Re: 1931 Shakedown, coolant foaming - 07/27/22 01:39 AM
Left over from sand casting the block I'll bet.
Posted By: Harrys31coach Re: 1931 Shakedown, coolant foaming - 07/27/22 01:28 PM
Hello Dave39MD,
"I have trouble moving these heads around when they are easy to get to. Any suggestions on how to make removal and replacement easier than it looks?" I would say that it is not as easy as it looks getting the head off and back on with the engine in the car. It gets crowded with helping hands while trying to muscle the head around at arms length. You might think about an engine hoist to lift and guide the head or if you can gain access to fork lift or tractor with forks. Remove one fork, chain up head to remaining fork, then lift and guide head onto position. I know it sounds like a pain, but it may be the help you need to keep you out of pain.
Posted By: Chipper Re: 1931 Shakedown, coolant foaming - 07/27/22 02:46 PM
Take an old broken off shovel handle, drill a couple of holes for the rocker shaft studs, put on a couple of nuts and washers and lift it out. Have done that several times. Makes the job easier both removing and replacing.
Posted By: Rusty 37 Master Re: 1931 Shakedown, coolant foaming - 07/27/22 03:12 PM
Dave,

Thanks for the update. While I know it is not what you had hoped I am glad that you found a possible reason for the problem.

I agree that using an engine hoist to remove a head is the way to go. Just make sure all the bolts are removed before you start lifting!

I like to use guide pins when I assemble parts like the head. You know the gasket stays in place. If I have extra head bolts I cut the head off and put a slot in the end so I can remove it with a screwdriver. An alternative is to cut about 1/2” of thread length on the end of a rod cut to length. If I can get it easily I use an aluminum rod. It’s easy to cut and thread..
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/27/22 04:32 PM
Lot's of good advice. I did not have any help so I did go out and buy an engine hoist. My third and last(I hope). The hoist did work well and I was able to go slow and easy. The head is at a good shop but the wait is several weeks.

Rusty the guide pins are a good idea and I have some left from a prior adventure.

Dave
Posted By: BearsFan315 Re: 1931 Shakedown, coolant foaming - 07/27/22 06:12 PM
guide pins are great :) have them for several components on the 1929
engine hoist is safest and easiest if alone. it truly is a 2 person job to get it set :) sure some can do it alone, been there done that

Attached picture 20210718_185434.jpg
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/30/22 11:59 AM
Getting things ready for the head to come back.

1. I measured all head bolts and they are all bout 4 3/16, maybe a hair less. I also went through a box of 20 or so head bolts I had been saving and all but one was the same. One was 4 1/4 and had an hour glass shape to it so it was obviously stretched. I don't see a problem reusing these but I may be missing something. Thoughts?

2. I am planning or retorquing in steps like 45, 55, and 65 in the proper order. Does that sound like a reasonable plan?

3. The head gasket has a smooth side and the side with folds around the openings. The one on the car was smooth side to the block but I was thinking smooth side to the head. Is there a proven way to put these on? Best Gasket says to use the copper coat but does not mention gasket orientation.

Thanks

Dave
Posted By: 1931Harlet Re: 1931 Shakedown, coolant foaming - 07/30/22 01:44 PM
Dave,
I would not use the bolt that is longer and has the hour glass shape. I believe the material has reached its yield strength and it no longer has its original strength. It may not be capable of being torqued down and will continue to elongate until it fails.
Posted By: Rustoholic Re: 1931 Shakedown, coolant foaming - 07/30/22 05:18 PM
John Thorpe (VCCA member), who is a Certified Caterpillar Mechanic, told me that when rebuilding a motor, Caterpillar REQUIRES all bolts that can be stretched to be replaced with new ones. Sounds like a good idea to me.

In another vein, George Childs (another VCCA guy) found LOTS of wires in the water jacket of his 1933 engine when it was rebuilt. He also speculated that these wires were left over from the original casting process.

Cheers, Dean
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/30/22 08:16 PM
Good points. I have been measuring and checking for stretching and found one in the engine and about a third in my stash that were questionable. I used my calipers around the threads long wise and holding up to a light which catches many that are starting to stretch.

Thanks

Dave
Posted By: cabboy Re: 1931 Shakedown, coolant foaming - 07/30/22 10:58 PM
If you hold another good bolt against it thread to thread any stretch will show up quickly. I went though 40-50 bolts to get a full set of good ones for my car.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/31/22 10:38 AM
Good idea Robin, thanks
Posted By: Chistech Re: 1931 Shakedown, coolant foaming - 07/31/22 11:28 AM
There was a guy who made a bunch of high head head bolts years ago from VT, I believe. He now owns a performance bicycle shop. You can. Find him by google. He sometimes has an add on eBay selling head bolts. Myself and my buddy Joe Pirronne were able to get complete new sets for our 32 Olds flatheads from him. He did have 1/2x12 which I believe the chevy uses.
Posted By: Chipper Re: 1931 Shakedown, coolant foaming - 07/31/22 11:32 AM
I have used the thread to thread comparison for many, many years. Far quicker and at least as accurate as using a die. Bad to bad, bad to good or good to good doesn't matter. If the threads from both of then don't nest together at least one of them is bad. Even stretched bolts will have a section of good threads generally where they go into the block. It is the section that goes through the head that stretches. Almost always the worst section is just above where they thread into the block.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/31/22 04:47 PM
Yes, thread to thread was the way to go. Much quicker but my big box of head bolts is now a baggie of good ones.

Any ideas on the head gasket orientation?

Dave
Posted By: Stovblt Re: 1931 Shakedown, coolant foaming - 07/31/22 05:08 PM
Gaskets I've installed in the past which had their orientation marked on them put the rolled edges toward the head, and the plain side toward the block.
So I've always done it that way.

Also, over time the rolled edge of the fire ring will sometimes leave an imprint on the surface it contacts.
I've always thought it is much better for that imprint to be on the head than on the block.
It's easier to deal with imperfections on the head.

I could of course be wrong. :-)
If I am, someone please correct me.
Posted By: Dave39MD Re: 1931 Shakedown, coolant foaming - 07/31/22 09:00 PM
Thanks Stoveblt that make sense.

Dave
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